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Single-Site Corticosteroid Injection Is as Effective as Multisite Corticosteroid Injection in the Nonsurgical Treatment of Frozen Shoulder: A Systematic Review With Meta-Analysis of Randomized Controlled Trials

  • DingYuan Fan
    Affiliations
    Department of Joint Surgery and Sports Medicine, Beijing, China

    Wang Jing Hospital, China Academy of Chinese Medical Sciences Beijing, China

    Beijing University of Chinese Medicine, Beijing, China
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  • Jia Ma
    Affiliations
    Department of Joint Surgery and Sports Medicine, Beijing, China

    Wang Jing Hospital, China Academy of Chinese Medical Sciences Beijing, China
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  • Lei Zhang
    Correspondence
    Address correspondence to Dr. Lei Zhang, M.D., Ph.D., Department of Joint Surgery and Sports Medicine, Wang Jing Hospital, China Academy of Chinese Medical Sciences, Beijing, China.
    Affiliations
    Department of Joint Surgery and Sports Medicine, Beijing, China

    Wang Jing Hospital, China Academy of Chinese Medical Sciences Beijing, China
    Search for articles by this author
Open AccessPublished:September 08, 2022DOI:https://doi.org/10.1016/j.asmr.2022.07.013

      Purpose

      To determine whether multisite corticosteroid injection is more effective than a single injection in the nonsurgical treatment of frozen shoulder (FS) via a meta-analysis of randomized controlled trials

      Methods

      We identified studies that evaluated the efficacy of multisite corticosteroid injections compared with single-site injection for FS. The Embase, PubMed, and Cochrane Library databases were systematically searched from inception to June 5, 2022. Methodologic quality and risk of bias were assessed using the Modified Coleman Methodology Score and the Cochrane Collaboration risk of bias tool, respectively. Visual analog scale scores, abduction, flexion, internal rotation, external rotation, American Shoulder and Elbow Surgeons Assessment Form scores, Constant–Murley Shoulder scores, and complications were extracted. The meta-analysis was conducted with random effects, and 4 time intervals were analyzed: 3 to 4 weeks, 6 to 8 weeks, 12 to 16 weeks, and 24 to 26 weeks

      Results

      The initial search identified 260 studies, and 5 randomized controlled trials that met the inclusion criteria were included. There were no significant differences in visual analog scale scores at 3 to 4 weeks, 6 to 8 weeks, 12 to 16 weeks, or 24 to 26 weeks. There were no significant differences in flexion or external rotation at 3 to 4 weeks, 6 to 8 weeks, 12 to 16 weeks, or 24 to 26 weeks. Multisite injection performed better in terms of abduction (mean difference –15.66 [–30.03, –1.28], P = .03) and American Shoulder and Elbow Surgeons Assessment Form score (mean difference –10.13 [–19.54, –0.72] P = .03) than single-site injection at 3 to 4 weeks. There were significant differences in internal rotation in favor of the multisite treatment at 3 to 4 weeks, 6 to 8 weeks, 12 to 16 weeks, and 24 to 26 weeks. In addition, there were no significant differences in complications.

      Conclusions

      Single-site steroid injection is as effective as multisite corticosteroid injection for the nonoperative treatment of FS.

      Level of Evidence

      Level II, meta-analysis of Level I and II studies.
      Frozen shoulder (FS), also known as adhesive capsulitis, is a common, self-limiting shoulder disorder, with an incidence rate of 2% to 5% in the general population.
      • van der Windt D.A.
      • Koes B.W.
      • de Jong B.A.
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      Shoulder disorders in general practice: Incidence, patient characteristics, and management.
      • Chaudhury S.
      • Gwilym S.E.
      • Moser J.
      • Carr A.J.
      Surgical options for patients with shoulder pain.
      • Rangan A.
      • Hanchard N.
      • McDaid C.
      What is the most effective treatment for frozen shoulder?.
      It has been characterized by the insidious onset of pain coupled with substantial restriction of active and passive movement of the glenohumeral joint.
      • Dias R.
      • Cutts S.
      • Massoud S.
      Frozen shoulder.
      ,
      • Walmsley S.
      • Osmotherly P.G.
      • Rivett D.A.
      Movement and pain patterns in early stage primary/idiopathic adhesive capsulitis: A factor analysis.
      As a result, patients often have difficulty performing daily activities and falling asleep at night.
      • Jump C.M.
      • Duke K.
      • Malik R.A.
      • Charalambous C.P.
      Frozen shoulder: A systematic review of cellular, molecular, and metabolic findings.
      ,
      • Jones S.
      • Hanchard N.
      • Hamilton S.
      • Rangan A.
      A qualitative study of patients’ perceptions and priorities when living with primary frozen shoulder.
      The current studies attempt to explain the molecular pathways mechanism of shoulder freezing from the perspective of immunobiology, which is still poorly understood.
      • Akbar M.
      • McLean M.
      • Garcia-Melchor E.
      • et al.
      Fibroblast activation and inflammation in frozen shoulder.
      ,
      • Akbar M.
      • Crowe L.A.N.
      • McLean M.
      • et al.
      Translational targeting of inflammation and fibrosis in frozen shoulder: Molecular dissection of the T cell/IL-17A axis.
      The diagnosis of FS is based on recognizing the characteristic features, and radiographs are only valuable for ruling out other pathologies of the shoulder joint.
      • Robinson C.M.
      • Seah K.T.
      • Chee Y.H.
      • Hindle P.
      • Murray I.R.
      Frozen shoulder.
      ,
      • Ramirez J.
      Adhesive capsulitis: Diagnosis and management.
      FS comprises 3 overlapping clinical stages: an insidious painful freezing phase (duration 10-36 weeks), a shoulder adhesive phase (duration 4-12 months), and a resolution phase (duration 12-42 months). Most patients experience spontaneously resolution in 2 or 3 years; however, the recovery might be beyond the estimated time frame or incomplete.
      • Robinson C.M.
      • Seah K.T.
      • Chee Y.H.
      • Hindle P.
      • Murray I.R.
      Frozen shoulder.
      ,
      • Rangan A.
      • Brealey S.D.
      • Keding A.
      • et al.
      Management of adults with primary frozen shoulder in secondary care (UK FROST): A multicentre, pragmatic, three-arm, superiority randomised clinical trial.
      ,
      • Hand C.
      • Clipsham K.
      • Rees J.L.
      • Carr A.J.
      Long-term outcome of frozen shoulder.
      In addition, simultaneous bilateral involvement occurs in 14% of the patients, and 20% of patients develop similar symptoms in the opposite shoulder.
      • Hand C.
      • Clipsham K.
      • Rees J.L.
      • Carr A.J.
      Long-term outcome of frozen shoulder.
      ,
      • Walker-Bone K.
      • Palmer K.T.
      • Reading I.
      • Coggon D.
      • Cooper C.
      Prevalence and impact of musculoskeletal disorders of the upper limb in the general population.
      Therefore, it is necessary to treat patients with FS to improve their quality of life.
      A myriad of treatment modalities are available for patients with FS, including oral analgesia, steroid injection, physiotherapy, hydrodistension, acupuncture, manipulation under anesthesia, and arthroscopic or open capsular release.
      • Rangan A.
      • Hanchard N.
      • McDaid C.
      What is the most effective treatment for frozen shoulder?.
      However, there is still uncertainty about the optimal option for patients and treating health care professionals.
      • Rangan A.
      • Hanchard N.
      • McDaid C.
      What is the most effective treatment for frozen shoulder?.
      ,
      • Challoumas D.
      • Biddle M.
      • McLean M.
      • Millar N.L.
      Comparison of treatments for frozen shoulder: A systematic review and meta-analysis.
      It is worth noting that corticosteroid injections, especially when coupled with physiotherapy exercise, have a better effect than a single treatment and are highly accepted in clinical practice at present.
      • Rangan A.
      • Brealey S.D.
      • Keding A.
      • et al.
      Management of adults with primary frozen shoulder in secondary care (UK FROST): A multicentre, pragmatic, three-arm, superiority randomised clinical trial.
      ,
      • Hanchard N.C.A.
      • Goodchild L.
      • Brealey S.D.
      • Lamb S.E.
      • Rangan A.
      Physiotherapy for primary frozen shoulder in secondary care: Developing and implementing stand-alone and post operative protocols for UK FROST and inferences for wider practice.
      ,
      • Blanchard V.
      • Barr S.
      • Cerisola F.L.
      The effectiveness of corticosteroid injections compared with physiotherapeutic interventions for adhesive capsulitis: A systematic review.
      Numerous previous studies have analyzed the effectiveness of different single injection sites in the shoulder. The effectiveness of multi-site corticosteroid injections is unknown.
      • Chen R.
      • Jiang C.
      • Huang G.
      Comparison of intra-articular and subacromial corticosteroid injection in frozen shoulder: A meta-analysis of randomized controlled trials.
      ,
      • Shang X.
      • Zhang Z.
      • Pan X.
      • Li J.
      • Li Q.
      Intra-articular versus subacromial corticosteroid injection for the treatment of adhesive capsulitis: A meta-analysis and systematic review.
      The purpose of this study was to determine whether multisite corticosteroid injection is more effective than a single injection in the nonsurgical treatment of FS via a meta-analysis of randomized controlled trials (RCTs). We hypothesized that multisite corticosteroid injection is superior to a single-site injection in pain relief, range of motion (ROM) and function for FS.

      Methods

      This review of literature adheres to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-analysis) statement and checklist.
      • Page M.J.
      • McKenzie J.E.
      • Bossuyt P.M.
      • et al.
      The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.

      Search Strategy

      Two authors independently searched the Embase, PubMed, and Cochrane Library databases from inception to June 5, 2022, and the reference lists of published systematic reviews for relevant studies. The search specifics were as follows: ‘‘(((((Multisite) OR (sites)) OR (dual-target)) OR (two targets)) AND (((((((((corticosteroid) OR (glucocorticoid)) OR (triamcinolone)) OR (methylprednisolone)) OR (hydrocortisone)) OR (prednisolone)) OR (cortisone)) OR (dexamethasone)) OR (betamethasone))) AND ((((((((((((((((((((((((Bursitides) OR (Bursitis)) OR (Periarthritis)) OR (Frozen Shoulder)) OR (Frozen Shoulders)) OR (Shoulder, Frozen)) OR (Adhesive Capsulitis of the Shoulder)) OR (Shoulder Adhesive Capsulitis)) OR (Adhesive Capsulitides, Shoulder)) OR (Adhesive Capsulitis, Shoulder)) OR (Capsulitides, Shoulder Adhesive)) OR (Capsulitis, Shoulder Adhesive)) OR (Shoulder Adhesive Capsulitides)) OR (Capsulitis)) OR (Capsulitides)) OR (Pes Anserine Bursitis)) OR (Bursitides, Pes Anserine)) OR (Bursitis, Pes Anserine)) OR (Pes Anserine Bursitides)) OR (Adhesive Capsulitis)) OR (Adhesive Capsulitides)) OR (Capsulitides, Adhesive)) OR (Capsulitis, Adhesive)) OR (Stiff Shoulder)).’’ No language restrictions or study types were imposed.

      Study Selection Process

      The same 2 authors independently screened all titles and abstracts for relevance and eligibility. After the screening, chance-adjusted agreement was assessed by kappa value (0-0.20, poor agreement; 0.21-0.40, fair agreement; 0.41-0.60, moderate agreement; 0.61-0.80, good agreement; and 0.81-1.00, perfect agreement).
      • McHugh M.L.
      Interrater reliability: The kappa statistic.
      A third author resolved any disagreements. Studies were reviewed if they met the following PICOS (patients, intervention, comparison, outcome, and study type) criteria:
      P: Patients with FS;
      I: Multisite corticosteroid injection;
      C: Single-site corticosteroid injection;
      O: Visual analog scale (VAS) score, ROM, American Shoulder and Elbow Surgeons (ASES) score,
      • Richards R.R.
      • An K.N.
      • LU Bigliani
      • et al.
      A standardized method for the assessment of shoulder function.
      or Constant–Murley score
      • Constant C.R.
      • Murley A.H.
      A clinical method of functional assessment of the shoulder.
      (at least 1 outcome); and
      S: Level I or II study.
      The exclusion criteria were as follows: (1) animal study; (2) cell study; (3) short communication or conference abstracts; and (4) intervention that did not involve steroid injections.

      Assessment of Literature and Methodologic Quality

      The same 2 authors used the Levels of Evidence for Primary Research Question to assess literature quality
      • Marx R.G.
      • Wilson S.M.
      • Swiontkowski M.F.
      Updating the assignment of levels of evidence.
      and the Modified Coleman Methodology Score (MCMS).
      • Coleman B.D.
      • Khan K.M.
      • Maffulli N.
      • Cook J.L.
      • Wark J.D.
      Studies of surgical outcome after patellar tendinopathy: clinical significance of methodological deficiencies and guidelines for future studies. Victorian Institute of Sport Tendon Study Group.
      The MCMS has a scaled potential score ranging from 0 to 100 to evaluate inclusion criteria, sample size calculation, randomization, follow-up, patient analysis, blinding, similarity in treatment, treatment description, group comparability, outcome assessment, description of rehabilitation protocol, clinical effect measurement, and the number of patients treated.
      • Coleman B.D.
      • Khan K.M.
      • Maffulli N.
      • Cook J.L.
      • Wark J.D.
      Studies of surgical outcome after patellar tendinopathy: clinical significance of methodological deficiencies and guidelines for future studies. Victorian Institute of Sport Tendon Study Group.
      A score of 85 to 100 means excellent, 70 to 84 means good, 55 to 69 means fair, and less than 55 means poor.
      • Coleman B.D.
      • Khan K.M.
      • Maffulli N.
      • Cook J.L.
      • Wark J.D.
      Studies of surgical outcome after patellar tendinopathy: clinical significance of methodological deficiencies and guidelines for future studies. Victorian Institute of Sport Tendon Study Group.
      The kappa score, which evaluates the degree of agreement between authors, was calculated.
      • McHugh M.L.
      Interrater reliability: The kappa statistic.

      Assessment of Risk of Bias

      The Cochrane Collaboration risk-of-bias tool was used to evaluate the risk of bias in the included studies; it contains the following domains: bias of random sequence generation (selection bias), bias of allocation concealment (selection bias), bias of blinding participants and personnel (performance bias), bias of blinding outcome assessment (detection bias), bias of missing outcome data (attrition bias), bias of selective reporting (reporting bias), and other bias.
      • Higgins J.P.
      • Altman D.G.
      • Gøtzsche P.C.
      • et al.
      The Cochrane Collaboration’s tool for assessing risk of bias in randomised trials.
      The same 2 authors independently assessed the bias of the included RCTs by scoring them as low, unclear, or high risk. Any discrepancies were resolved by discussion, and the third reviewer made the final decision.

      Data-Extraction Process

      Two same authors independently collected available data from the included studies. The following essential characteristics were collected: author, year, journal, country, male sex, age, duration of symptoms, follow-up, Level of Evidence, inclusion criteria, injection material, injection content, injection site, ultrasonographic guidance, approach, and physiotherapy program. In addition, VAS pain scores, abduction, flexion, internal rotation, external rotation, ASES Assessment Form scores,
      • Richards R.R.
      • An K.N.
      • LU Bigliani
      • et al.
      A standardized method for the assessment of shoulder function.
      Constant–Murley Shoulder scores,
      • Constant C.R.
      • Murley A.H.
      A clinical method of functional assessment of the shoulder.
      and complications were extracted as outcome measurements, and 4 time intervals of these measures were analyzed. We contacted the author to obtain missing data and extracted the mean value using Origin software (Version 2021; OriginLab Corp., Northampton, MA) when data were presented in figures.

      Data Synthesis

      This meta-analysis was performed with Review Manager, version 5.3 (The Cochrane Collaboration,). Statistical heterogeneity was assessed with I2 statistics as follows: 0% < I2 < 25%, unimportant heterogeneity; 25% < I2 < 50%, moderate heterogeneity; and I2 > 50%, important heterogeneity. We used a random-effects model for all comparisons because disease phases increase the risk of heterogeneity. The treatment effects of all continuous were measured by mean differences (MDs) with 95% confidence intervals (95% CIs). Dichotomous were measured by risk ratios and 95% CIs. If the comparisons with more than 1 met eligible intervention groups, the control group was divided into more groups with a smaller sample size that allowed all suitable comparisons to be included.
      • Cumpston M.
      • Li T.
      • Page M.J.
      • et al.
      Updated guidance for trusted systematic reviews: A new edition of the Cochrane Handbook for Systematic Reviews of Interventions.
      If the outcome measures were reported as the mean and 95% CI, standard deviation (SD) values were estimated using “Finding the Standard Deviation using Confidence Intervals” in the Excel version of the RevMan Calculator (Microsoft, Redmond, WA). When the outcome measures were reported in the mean and standard error of the mean, SD values were estimated with the following formula: SD = standard error of the mean × sqrt(n), where sqrt is the square root and n is the number of participants.
      In all analyses, a P value of .05 was considered statistically significant. Data analyses were performed for the following intervals: (1): 3 to 4 weeks; (2): 6 to 8 weeks; (3): 12 to 16 weeks, and (4): 24 to 26 weeks. When the number of included studies was less than 10, publication bias was not considered.
      • Cumpston M.
      • Li T.
      • Page M.J.
      • et al.
      Updated guidance for trusted systematic reviews: A new edition of the Cochrane Handbook for Systematic Reviews of Interventions.
      To assess the robustness of the effect sizes, we performed a sensitivity analysis by extracting all high heterogeneity results that synthesized more than 2 studies during 4 time intervals

      Results

      Identification of Studies

      The results of the initial search yielded 260 studies (PubMed = 21, Embase = 126, Cochrane = 113). After the removal of 27 duplicates, 233 studies remained, and 5 were deemed eligible for further screening. Thus, 5 studies were carefully reviewed.
      • Aslani M.
      • Mirzaee F.
      • Najafi A.
      • et al.
      Intra-articular along with subacromial corticosteroid injection in diabetic patients with adhesive capsulitis.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      However, one study
      • Aslani M.
      • Mirzaee F.
      • Najafi A.
      • et al.
      Intra-articular along with subacromial corticosteroid injection in diabetic patients with adhesive capsulitis.
      was a short communication that did not meet our inclusion criteria, and one additional study
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      was identified from the citation search. Finally, 5 RCTs were included in this review
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      (Fig 1). The kappa score was 0.88, indicating perfect agreement.
      Figure thumbnail gr1
      Fig 12020 PRISMA flow chart. The authors followed the 2020 PRISMA guidelines. (PRISMA, Preferred Reporting Items for Systematic Reviews and Meta-Analyses.)

      Basic Characteristics of Included Studies

      All of the studies were published in different journals. Of the 5 studies, 2 RCTs
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      were from South Korea, and the others were from Norway,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      India,
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      and Turkey.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      The minimum follow-up time was 12 weeks.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      There were three Level I and two Level II studies (Table 1).
      Table 1Characteristics of the Studies Included in this Systematic Review
      StudyYearJournalCountryMaleAgeDuration of symptomsFollow-upLOE
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      2013Journal of Shoulder and Elbow SurgerySouth KoreaIA: 16IA: 55.1 ± 4.6
      Mean ± SD.
      IA: 7.4 ± 3.46
      Mean ± SD.
      mo
      24 wk
      SA: 14SA: 53.9 ± 4.16
      Mean ± SD.
      SA: 7.7 ± 3.36
      Mean ± SD.
      mo
      IA+SA: 14IA+SA: 56.3 ± 5.86
      Mean ± SD.
      IA+SA: 7.0 ± 2.66
      Mean ± SD.
      mo
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      2015PainNorwayIA: 15IA: 53.2 ± 6.96
      Mean ± SD.
      IA: 15.1 ± 4.66
      Mean ± SD.
      wk
      26 wk
      Combined: 15Combined: 55 ± 7.26
      Mean ± SD.
      Combined: 15.0 ± 5.96
      Mean ± SD.
      wk
      Sham: 14Sham: 55.4 ± 7.26
      Mean ± SD.
      Sham: 15.0 ± 5.66
      Mean ± SD.
      wk
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      2016Joint Bone SpineSouth KoreaIA:10IA: 59.1 ± 7.9aIA: 5.3 ± 3.66
      Mean ± SD.
      mo
      12 wk
      SA: 16SA: 56.0 ± 9.46
      Mean ± SD.
      SA: 4.6 ± 3.56
      Mean ± SD.
      mo
      IA+SA: 18IA+SA: 54.8 ± 8.36
      Mean ± SD.
      IA+SA: 5.0 ± 4.56
      Mean ± SD.
      mo
      Pushpasekaran et al.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      2017Journal of Orthopaedic SurgeryIndiaSS: 12SS: 56.4 ± 4.326
      Mean ± SD.
      SS: 15.2 ± 13.746
      Mean ± SD.
      24 wk
      TS: 17TS: 56.24±5.42aTS: 14.82 ± 13.656
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      2021Arthroscopy: The Journal of Arthroscopic and Related SurgeryTurkeySI: 9SI: 54 ± 5.66
      Mean ± SD.
      SI: 2.8 ± 1.56
      Mean ± SD.
      48 wk
      MI: 13MI: 53.7 ± 7.76
      Mean ± SD.
      MI: 2.7 ± 1.76
      Mean ± SD.
      IA, intra-articular; LOE, Level of Evidence; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection; SS, single site; TS, three sites.
      Mean ± SD.
      All studies included patients with shoulder pain and limited motion. Specifically, one study inclusion criteria were pained with limitation of both active and passive shoulder movements in at least 2 directions (forward flexion <120° or 50% restriction of contralateral external rotation and internal rotation).
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      In addition, patients in two studies were assessed for pain and passive restriction of shoulder motion.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      One study
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      did not report the specific restriction, whereas another study
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported that inclusion criteria for patients had lost more than 20% of their shoulder movements in all directions. Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      used 2 different length needles (3 cm and 6 cm) for intra-articular and subacromial injection respectively. One study
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      used a 16-gauge needle, and another study
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      only reported 20-mL needles. Three studies used a 40-mg dose for injection,
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      and a 20-mg dose was used in one study.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      A sham injection was performed in one study.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      In addition, one RCT used a 40-mg dose for single-site injection and 80 mg for multisite injection.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      In this study, injection sites include the glenohumeral joint, posteroinferior capsule, subacromial space, posterosuperior capsule, biceps long head, and area around the coracohumeral ligament. Multisite injection was selected for the glenohumeral joint combined with the subacromial space in 2 studies.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      Three injection sites were selected in one RCT,
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      and 4 sites were selected in one study.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Ultrasound-assisted injection was reported in 4 studies.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      Except for 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      , reporting 2 approaches of multisite injection, all injection approaches were posterior approaches. Three RCTs reported the combination of physical therapy and injections (Table 2).
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Table 2Summary of Injection Administrations
      AuthorInclusion CriteriaInjection MaterialInjection ContentCorticosteroid Injection SiteUS-GuidedApproachPhysiotherapy Program
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      Pain with limitation of both active and passive shoulder movement in at least 2 directions (forward flexion <120° or 50% restriction of contralateral external rotation and internal rotation)NSIA: 40 mg of triamcinolone (1 mL) with 4 mL of 2% lidocaine.IA: glenohumeral jointYesPosteriorYes
      SA: 40 mg of triamcinolone (1 mL) with 4 mL of 2% lidocaine.SA: Subacromial space
      IA+SA: 40 mg of triamcinolone (1 mL) with 4 mL of 2% lidocaine equally divided between the 2 sites.IA+SA: glenohumeral joint combined with subacromial space
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      Pain and stiffness restriction of passive motion 30° in 2 or more planes of movementNSIA: 20 mg of triamcinolone hexacetonide (1 mL) with 2.5 mL lidocaine. 3.5 mL lidocaine10 mg/mL into the rotator interval/anterior capsule.IA: glenohumeral jointYesPosteriorNR
      Combined group: 10 mg of triamcinolone (0.5 mL) + 3 mL lidocaine into the 2 sites.Combined group: glenohumeral joint + along with the long head of the biceps and into the anterior capsule
      Sham group: 3.5 mL lidocaine injected into the 2 sites.Sham group: glenohumeral joint + along with the long head of the biceps and into the anterior capsule
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      Pain with limitation of passive motion of greater than 30 ˚ in two or more planes of movement (stage 2 or 3)IA: a 25-gauge,

      6-cm-long needle
      IA: 40 mg of triamcinolone acetonide and 4 mL of 1% lidocaineIA: glenohumeral jointYesIA: Posterior

      SA: Superior

      IA+SA: Posterior and Superior
      Yes
      SA: a 25-gauge, 3-cm-long needleSA: 40 mg of triamcinolone acetonide and 4 mL of 1% lidocaineSA: subacromial space
      IA+SA: 25-gauge, 3- and 6-cm-long needleIA+SA: 40 mg of triamcinolone acetonide and 4 mL of 1% lidocaine equally divided between the 2 sites.IA+SA: glenohumeral joint combined with subacromial space
      Pushpasekaran et al.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      Pain and restricted movements16-gauge needleSS: 40 mg of methylprednisolone acetate mixed with 2 mL of 2% lignocaineSS: glenohumeral jointNSPosteriorNR
      TS: 40 mg of methylprednisolone acetate mixed with 2 mL of 2% lignocaine and 8 mL of normal saline and instilled at 3 sitesTS: posterior capsule, subacromial and subcoracoid
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Pain and a loss of ROM greater than 20% in all directions (stage 2)20-mL syringesSI: 40 mg of triamcinolone acetonide (1 mL) and 2 mL of bupivacaine (0.5%)SI: glenohumeral jointYesSI: PosteriorYes
      MI
      NOTE: 5 mL into the glenohumeral joint, 5 mL into the posteroinferior capsule, 10 mL into the posterosuperior capsule, and 10 mL into the biceps long head and around the coracohumeral ligament.
      : 80 mg (40 mg/mL) of triamcinolone acetonide (2 mL), 4 mL of bupivacaine (0.5%), and 34 mL of saline solution (total 40 mL).
      MI: Glenohumeral joint and posteroinferior capsule (site 1)

      Subacromial space (site 2)

      Posterosuperior capsule (site 3)

      Biceps long head and area around the coracohumeral ligament (site 4)
      MI: Posterior (sites 1 and 2)

      Superomedial (sites 3 and 4)
      DT, dual-target; IA, intra-articular; LOE, Level of Evidence; MI, multisite injection; NS, not shown; ROM, range of motion; SA, subacromial; SI, single injection; SS, single site; ST, standard target; TS, three sites; US-Guided, ultrasonography-guided.
      NOTE: 5 mL into the glenohumeral joint, 5 mL into the posteroinferior capsule, 10 mL into the posterosuperior capsule, and 10 mL into the biceps long head and around the coracohumeral ligament.

      Assessment of Literature and Methodologic Quality

      According to the MCMS, there were 3 excellent quality studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      and 2 good-quality studies.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      Only one study obtained a score for follow-up, reducing the variability among studies.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Two studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      received fair scores in the description of the surgical procedure, and 2 studies
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      did not receive any points for postoperative rehabilitation that may hinder the clinical interpretation of the results. Only 1 study
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      obtained a perfect score in assessing outcomes that enhanced the efficacy of the clinical results. However, the scores of this study
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      were reduced in the description of the subject selection process due to the long assessment period and the small number of patients lost to follow-up (Table 3). There was a very good agreement between authors according to the kappa score (0.88).
      Table 3Modified Coleman Methodology Score (MCMS)
      AssessmentShin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      Pushpasekaran et al.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Part A1. Study size1010101010
      2. Mean Follow-up00002
      3. Number of different surgical procedures1010101010
      4. Type of study1515151015
      5. Diagnostic certainty55555
      6. Description of the surgical procedure given33555
      7. Description of postoperative rehabilitation10010010
      Part B1. Outcome criteria1010101010
      2. Procedure to assess outcomes81212915
      3. Description of the subject selection process1515151513
      Total score8680927495

      Assessment of Risk of Bias

      All 5 studies had a low risk of bias in random sequence generation and allocation concealment. One study was a single-blind clinical study, which increased the risk of performance bias.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      There was no detailed description of the blinding method used in the process in the 3 studies,
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      and there was an unclear risk of performance bias and detection bias. Pushpasekaran et al.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      only reported Constant-Murley score, and they did not report total structured values, such as SD or standard error and other outcomes. Thus, this study was rated as having a high risk of attrition bias and reporting bias. Finally, 3 studies did not report the experience of the injectors, indicating that they had unclear risks
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      (Fig 2).

      Visual Analog Scale

      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported VAS scores at 3 to 4 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures (Appendix Table 1, available at www.arthroscopyjournal.org). The results revealed that there were no statistically significant differences in VAS scores (MD 1.19 [–0.05 to 2.43], P = .06), and the heterogeneity was high (I2 = 90%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 3).
      Figure thumbnail gr3
      Fig 3Forest plot showing the results of visual analog scale scores. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for VAS scores (MD 0.77 [–0.46 to 2.01], P = .22), and the heterogeneity was 85%. (Appendix Figure 1, available at www.arthroscopyjournal.org)
      Three studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported VAS scores at 6 to 8 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in VAS scores (MD 0.38 [–0.66 to 1.41], P = .48), and the heterogeneity was high (I2 = 77%; P = .01). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported VAS scores at 12 to 16 weeks. The results revealed that there were no statistically significant differences in VAS scores (MD 0.54 [–0.10 to 1.17], P = .10), and the heterogeneity was high (I2 = 83%; P < .0001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data. When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 3 studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for VAS scores (MD 0.20 [–0.08 to 0.48], P = .17), and the heterogeneity was 16%.
      Three studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported VAS scores at 24 to 26 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in VAS scores (MD 0.50 [–1.26 to 2.27], P = .58), and the heterogeneity was high (I2 = 87%; P = .006). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.

      Abduction

      Three studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported abduction at 3 to 4 weeks (Appendix Table 2, available at www.arthroscopyjournal.org). The results revealed that the multisite group had better abduction than the single-site group (MD –15.66 [–30.03 to –1.28], P = .03), and the heterogeneity was high (I2 = 83%; P = .0006). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 4).
      Figure thumbnail gr4
      Fig 4Forest plot showing the results of abduction. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for abduction (MD –11.07 [–26.20 to 4.07], P = .15), and the heterogeneity was 80% (Appendix Figure 2, available at www.arthroscopyjournal.org).
      Two studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported abduction at 6 to 8 weeks. The results revealed that there were no statistically significant differences in abduction (MD –6.65 [–16.38 to 3.07], P = .18), and the heterogeneity was high (I2 = 63%; P = .07). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      Three studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported abduction at 12 to 16 weeks. The results revealed that there were no statistically significant differences in abduction (MD –13.35 [–28.61 to 1.90], P = .09), and the heterogeneity was high (I2 = 85%; P = .0001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data. When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for abduction (MD –5.68 [–12.34 to 0.97], P = .09), and the heterogeneity was 4%.
      Two studies
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported abduction at 24 to 26 weeks. The results revealed that there were no statistically significant differences in abduction (MD –15.11 [–51.44 to 21.23], P = .42), and the heterogeneity was high (I2 = 91%; P = .0007). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.

      Flexion

      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported flexion at 3 to 4 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures (Appendix Table 3, available at www.arthroscopyjournal.org). The results revealed that there were no statistically significant differences in flexion (MD –12.21 [–24.49 to 0.08], P = .05), and the heterogeneity was high (I2 = 85%; P = .0002). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 5).
      Figure thumbnail gr5
      Fig 5Forest plot showing the results of flexion. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for flexion (MD –7.93 [–20.11 to 4.25], P = .20), and the heterogeneity was 79% (Appendix Figure 3, available at www.arthroscopyjournal.org).
      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported flexion at 6 to 8 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in flexion (MD –11.55 [–24.69 to 1.60], P = .09), and the heterogeneity was high (I2 = 88%; P < .0001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for flexion (MD –5.68 [–14.61 to 3.13], P = .20), and the heterogeneity was 63%.
      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported flexion at 12 to 16 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in flexion (MD –8.19 [–21.17 to 4.89], P = .22), and the heterogeneity was high (I2 = 86%; P < .0001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      showed no significant differences between multisite group and single-site group for flexion (MD –2.51 [–12.50 to 7.47], P = .09), and the heterogeneity was 69%. Two studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported flexion at 24 to 26 weeks, and one study
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      presented the results in figures.

      External Rotation

      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported external rotation at 3-4 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures (Appendix Table 4, available at www.arthroscopyjournal.org). The results revealed that there were no statistically significant differences in external rotation (MD –7.85 [–16.87 to 1.17], P = .09), and the heterogeneity was high (I2 = 90%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 6).
      Figure thumbnail gr6
      Fig 6Forest plot showing the results of external rotation. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      favor multisite group for external rotation (MD –11.31 [–18.71 to –3.92], P = .003), and the heterogeneity was 76% (Appendix Figure 4, available at www.arthroscopyjournal.org).
      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported external rotation at 6-8 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in external rotation (MD –7.83 [–18.46 to 2.79], P = .15), and the heterogeneity was high (I2 = 93%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      , the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      favor multisite group for external rotation (MD –11.76 [–20.71 to –2.81], P = .010), and the heterogeneity was 85%.
      Four studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported external rotation at 12 to 16 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures. The results revealed that there were no statistically significant differences in external rotation (MD –6.95 [–18.04 to 4.14], P = .22), and the heterogeneity was high (I2 = 92%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      the pooled analysis of 2 studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      favor multisite group for external rotation (MD –11.19 [–20.30 to –2.08], P = .02), and the heterogeneity was 84%.
      Two studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported external rotation at 24 to 26 weeks, and one study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      presented the results in figures.

      Internal Rotation

      Two studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported internal rotation at 3-4 weeks (Appendix Table 5, available at www.arthroscopyjournal.org). The results revealed that there were significant differences in internal rotation in favor of the multisite treatment (MD –12.80 [–19.26 to –6.34], P = .0001), and the heterogeneity was high (I2 = 63%; P = .07). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 7).
      Figure thumbnail gr7
      Fig 7Forest plot showing the results of internal rotation. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      Two studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported internal rotation at 6 to 8 weeks. The results revealed that there were significant differences in internal rotation in favor of the multisite treatment (MD –12.10 [–19.83 to –4.37], P = .002), and the heterogeneity was high (I2 = 79%; P = .008). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      Two studies
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported internal rotation at 12 to 16 weeks. The results revealed that there were significant differences in internal rotation in favor of the multisite treatment (MD –11.06 [–19.11 to –3.01], P = .007), and the heterogeneity was high (I2 = 78%; P = .010). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.

      ASES Score

      Three studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported ASES scores at 3 to 4 weeks (Appendix Table 6, available at www.arthroscopyjournal.org).). The results revealed that there were significant differences in ASES scores in favor of the multisite treatment (MD –10.13 [–19.54, –0.72], P = .03), and the heterogeneity was high (I2 = 87%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data (Fig 8).
      Figure thumbnail gr8
      Fig 8Forest plot showing the results of American Shoulder and Elbow Surgeons Assessment Form scores. (CI, confidence interval; IV, inverse variance; SD, standard deviation.)
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      showed no significant differences between multisite group and single-site group for ASES scores (MD –6.79 [–15.24 to 1.66], P = .12), and the heterogeneity was 80% (Appendix Figure 5, available at www.arthroscopyjournal.org).
      Three studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported ASES scores at 6 to 8 weeks. The results revealed that there were no statistically significant differences in ASES scores (MD –7.46 [–17.45 to 2.53] P = .14), and the heterogeneity was high (I2 = 88%; P < .00001). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      showed no significant differences between multisite group and single-site group for ASES scores (MD –3.07 [–9.55 to 3.42], P = .35), and the heterogeneity was 64%.
      Three studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      reported ASES scores at 12 to 16 weeks. The results revealed that there were no statistically significant differences in ASES scores (MD –6.36 [–13.00 to 0.28] P = .06), and the heterogeneity was high (I2 = 66%; P = .02). The result suggests that current statistics are underpowered, which makes it hard to draw strong inferences from the available data.
      When we excluded the study that caused the greatest heterogeneity due to bias,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      the pooled analysis of 2 studies
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      showed no significant differences between multisite group and single-site group for ASES scores (MD –3.64 [–9.10 to 1.81], P = .19), and the heterogeneity was 32%. One study
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      reported the ASES scores at 24 to 26 weeks.

      Complications

      Five studies reported complications.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      (Appendix Table 7, available at www.arthroscopyjournal.org) However, 2 studies did not report whether the patients belonged to the multisite injection group or the single site injection group, so the results could not be further analyzed.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      The poor results revealed that there were no statistically significant differences in complication events (risk ratio 0.41 [0.11-1.57]), and the heterogeneity was low (I2 = 8%; P = .19) (Fig 9).
      Figure thumbnail gr9
      Fig 9Forest plot showing the results of complications. (CI, confidence interval; MH, Mantel-Haenszel.)

      Discussion

      Most clinical outcomes assessed in this study (VAS scores, abduction, flexion, external rotation, and ASES scores) showed no significance between multisite group and single-site group with high heterogeneity that make a conclusion from the results unreliable. In most sensitivity analyses, the greatest heterogeneity in Koraman et al.’s study
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      was due to the fact that more than 2 injection sites were used in multisite injection. In addition, the total dose of multipoint injection exceeding the conventional dose also may be the cause of heterogeneity. In the sensitivity analysis of external rotation results, when we excluded Prestgaard et al.’s study
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      which had the greatest heterogeneity, the results tended to be more advantageous for multipoint injection. This may due to the use of lidocaine as a control in the nonsteroid injection area of the joint, which may have somewhat skewed the results. Therefore, it is difficult to draw a clear conclusion. Our hypothesis was not proved according to the results of the current systematic literature and meta-analysis. We only can expect that multisite steroid injection has similarly effective compared with single-site corticosteroid injections for FS.
      Identification of the lesion site is essential for treatment. At first, FS was thought to be a glenohumeral joint disorder or associated with subacromial bursa inflammation and thickening.
      • Jump C.M.
      • Duke K.
      • Malik R.A.
      • Charalambous C.P.
      Frozen shoulder: A systematic review of cellular, molecular, and metabolic findings.
      However, a growing body of research suggests that inflammation with vascularity and thickening of the rotator interval, capsule, and glenohumeral ligaments are pathologically pivotal to the driving process.
      • Akbar M.
      • Crowe L.A.N.
      • McLean M.
      • et al.
      Translational targeting of inflammation and fibrosis in frozen shoulder: Molecular dissection of the T cell/IL-17A axis.
      ,
      • Ryu J.D.
      • Kirpalani P.A.
      • Kim J.M.
      • Nam K.H.
      • Han C.W.
      • Han S.H.
      Expression of vascular endothelial growth factor and angiogenesis in the diabetic frozen shoulder.
      • Hand G.C.
      • Athanasou N.A.
      • Matthews T.
      • Carr A.J.
      The pathology of frozen shoulder.
      • Lho Y.M.
      • Ha E.
      • Cho C.H.
      • et al.
      Inflammatory cytokines are overexpressed in the subacromial bursa of frozen shoulder.
      Therefore, intervention in these structures is vital to alleviate FS.
      There are multiple conventional approaches for shoulder injection (the anterior approach, lateral approach, and posterior approach), and practitioners most commonly use the posterior approach.
      • Tobola A.
      • Cook C.
      • Cassas K.J.
      • et al.
      Accuracy of glenohumeral joint injections: Comparing approach and experience of provider.
      • Daley E.L.
      • Bajaj S.
      • Bisson L.J.
      • Cole B.J.
      Improving injection accuracy of the elbow, knee, and shoulder: Does injection site and imaging make a difference? A systematic review.
      • Tallia A.F.
      • Cardone D.A.
      Diagnostic and therapeutic injection of the shoulder region.
      Most of the studies we included also adopted this approach, which has the advantage that it is easier to palpate bony surface landmarks, especially for patients with obesity or who are muscular. It is also favorable for simultaneous intra-articular injection and subacromial space injection. In addition, the posterior approach is not affected by osteophytes or a hooked acromion compared to the anterior approach. However, for distant lesions, such as anterior glenohumeral joint lesions and biceps tendon lesions, treatment may be less effective. Therefore, an appropriate approach should be selected according to injection site when using multisite injection. In addition, when the multisite injection is performed using a single approach, the needle passes through the patient’s muscle tissue without an anesthetic, which undoubtedly causes fear and pain in the patient and makes the patient’s body tense, which may affect the patient and injection at the next point. Multiple approaches to multipoint injection also increase pain in patients initially.
      In multisite injection, the choices of injection site and number of injections are not uniform. Only 2 of the 5 studies included selected the glenohumeral joint combined with subacromial space for multipoint injection procedures.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      ,
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      reported the use of glenohumeral joint and rotator interval as sites for multisite injection. They concluded that there were no significant differences between the groups. However, the remaining 2 studies selected 3 and 4 sites, and they concluded that the differences were significant.
      • Pushpasekaran N.
      • Kumar N.
      • Chopra R.K.
      • Borah D.
      • Arora S.
      Thawing frozen shoulder by steroid injection.
      ,
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      Therefore, the selection of injection site and number of injections is still worth considering by researchers. If only multiple appropriate sites can be superimposed, ultrasound may be used more frequently to locate these areas accurately.
      Another consideration is the dosage of steroids. Increasing the drug dose may be inevitable for multisite injection as the number of injection sites increases. Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      used 80 mg (40 mg/mL) triamcinolone acetonide for multisite injection. The main side effects of steroids were transient pain, tendon ruptures, local depigmentation of the skin, disturbance of the menstrual pattern, hot flash-like symptoms, hyperglycemia in diabetes mellitus, nerve damage and infection.
      • Gaujoux-Viala C.
      • Dougados M.
      • Gossec L.
      Efficacy and safety of steroid injections for shoulder and elbow tendonitis: A meta-analysis of randomised controlled trials.
      • Nguyen M.L.
      • Jones N.F.
      Rupture of both the abductor pollicis longus and extensor pollicis brevis tendons after steroid injection for de quervain tenosynovitis.
      • Jacobs J.W.
      • Michels-van Amelsfort J.M.
      How to perform local soft-tissue glucocorticoid injections?.
      • Stout A.
      • Friedly J.
      • Standaert C.J.
      Systemic absorption and side effects of locally injected glucocorticoids.
      Therefore, even though the solution is divided into different sites, caution is still needed. However, dividing a drug intended for one injection site equally among multiple injection sites can lead to underdosing and skewing the outcome. The optimal dose is still worth exploring.

      Implications for Research

      We suggest that future trials investigating the effect of multisite steroid injections on FS use the following parameters:
      P: Patients with FS (better to specify the stage of the disease);
      I: Multisite steroid injection (20-40 mg dose may be better for one injection site and it is better to have three or more sites for multiple injection);
      C: Single steroid injection;
      O: VAS, ROM, shoulder function score (such as the ASES score, CMS score, and UCLA score), and adverse events; and
      S: Randomized study or other type clinical trial.
      In addition, we are still curious about whether similar results could be found for rotator cuff injuries, subacromial impingement syndrome, or other shoulder diseases and whether hyaluronic or platelet-rich plasma injections could be similarly helpful. The most appropriate injection site, the number of injection sites, and the drug dosage also need to be further explored.

      Limitations

      The primary limitation of this study is that only 5 studies have been conducted on the relevant topic. Although we included the outcomes of each period in the analysis as much as possible, the conclusions were still unstable due to the insufficient number of included studies, Therefore, we cannot determine the optimal dose and injection site. Second, we included the same outcome at 4 time intervals in the data analysis due to the number of included studies. Third, In the process of extracting data, some studies did not report the mean or SD of clinical outcomes, which also limited the analysis data we included. In addition, some literatures did not report specific grouping of patients with postoperative complications, which may lead to biased results. Nevertheless, the duration of each stage of FS was inconsistent among patients, or the onset of each stage overlapped, which may affect the final accuracy of the results. Finally, although most studies used ultrasound injection, there was no literature to report the accuracy of multipoint injection, so we could not compare the accuracy of single and multipoint injection.

      Conclusions

      Single-site steroid injection is as effective as multisite corticosteroid injection for the nonoperative treatment of FS.

      Appendix

      Appendix Table 1Visual Analog Scale (VAS) Scores, Reported as the Mean Only, Mean With 95% CI, Mean ± SD, or Mean ± SE
      AuthorVAS
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      IA: 6.10909
      Mean only (extracted from graphs).


      SA: 7.03316
      Mean only (extracted from graphs).


      IA+SA: 7.15294
      Mean only (extracted from graphs).
      IA: 1.48021
      Mean only (extracted from graphs).


      SA: 2.53262
      Mean only (extracted from graphs).


      IA+SA: 1.48877
      Mean only (extracted from graphs).
      IA: 1.49733
      Mean only (extracted from graphs).


      SA: 1.68556
      Mean only (extracted from graphs).


      IA+SA: 1.12941
      Mean only (extracted from graphs).
      IA: 1.4 ± 0.4
      Mean ± SD.


      SA: 1.4 ± 0.5
      Mean ± SD.


      IA+SA:1.2 ± 0.8
      Mean ± SD.
      IA: 0.96684
      Mean only (extracted from graphs).


      SA: 1.30909
      Mean only (extracted from graphs).


      IA+SA: 1.42032
      Mean only (extracted from graphs).
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      IA: 6.1 (5.8-6.4)
      Mean with 95% CI.


      Combined group: 6.4 (6.1-6.7)
      Mean with 95% CI.
      IA: 4.3 (3.7-4.9)
      Mean with 95% CI.


      Combined group: 3.7 (3.1-4.3)
      Mean with 95% CI.
      IA: 3.2 (2.5-3.9)
      Mean with 95% CI.


      Combined group: 2.8 (2.0-3.5)
      Mean with 95% CI.
      IA: 2.2 (1.5-2.9)
      Mean with 95% CI.


      Combined group: 2.6 (1.9-3.3)
      Mean with 95% CI.
      IA: 1.8 (1.2-2.5)
      Mean with 95% CI.


      Combined group: 2.2 (1.5-2.8)
      Mean with 95% CI.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 7.9 ± 1.5
      Mean ± SD.


      SA: 7.9 ± 1.1
      Mean ± SD.


      IA+SA: 8.2 ± 1.6
      Mean ± SD.
      IA: 2.5 ± 1.4
      Mean ± SD.


      SA: 4.7 ± 2.3
      Mean ± SD.


      IA+SA: 2.7 ± 1.2
      Mean ± SD.
      IA: 1.8 ± 1.3
      Mean ± SD.


      SA: 3.6 ± 2.1
      Mean ± SD.


      IA+SA: 2.3 ± 1.4
      Mean ± SD.
      IA: 2.2 ± 1.8
      Mean ± SD.


      SA: 3.3 ± 1.9
      Mean ± SD.


      IA+SA: 2.3 ± 1.5
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      SI: 8.4 ± 1.3
      Mean ± SD.


      MI: 8.7 ± 1.1
      Mean ± SD.
      SI: 4.4 ± 1.8
      Mean ± SD.


      MI: 2 ± 1.6
      Mean ± SD.
      SI: 4.1 ± 1.9
      Mean ± SD.


      MI: 1.7 ± 1.8
      Mean ± SD.
      SI: 3.3 ± 1.9
      Mean ± SD.


      MI: 1.9 ± 2.1
      Mean ± SD.
      CI, confidence interval; IA, intra-articular; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection.
      Mean only (extracted from graphs).
      Mean with 95% CI.
      Mean ± SD.
      Appendix Table 2Abduction, Reported as the Mean or Mean With 95% CI, Mean ± SD
      AuthorAbduction
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      IA: 54.5 (46.7-62.3)
      Mean with 95% CI.


      Combined group:61.8 (53.6-69.9)
      Mean with 95% CI.
      IA: 73.0 (64.6-81.3)
      Mean with 95% CI.


      Combined group: 76.3 (67.8-84.8)
      Mean with 95% CI.
      IA: 87.5 (76.4-98.5)
      Mean with 95% CI.


      Combined group: 89.5 (78.3-100.7)
      Mean with 95% CI.
      IA: 99.3 (87.7-111.0)
      Mean with 95% CI.


      Combined group: 105.4 (93.6-117.1)
      Mean with 95% CI.
      IA: 116.7 (103.6-129.8)
      Mean with 95% CI.


      Combined group: 112.6 (99.3-125.8)
      Mean with 95% CI.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 110.0 ± 25.0
      Mean ± SD.


      SA: 109.2 ± 29.5
      Mean ± SD.


      IA+SA: 108.5 ± 24.4
      Mean ± SD.
      IA: 149.4 ± 22.0
      Mean ± SD.


      SA: 124.9 ± 32.4
      Mean ± SD.


      IA+SA: 152.6 ± 16.5
      Mean ± SD.
      IA: 158.6 ± 12.2
      Mean ± SD.


      SA: 144.3 ± 28.9
      Mean ± SD.


      IA+SA: 160.5 ± 11.0
      Mean ± SD.
      IA: 158.1 ± 19.1
      Mean ± SD.


      SA: 147.6 ± 24.1
      Mean ± SD.


      IA+SA: 158.9 ± 15.9
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      SI: 73.7 ± 14.4
      Mean ± SD.


      MI: 73.2 ± 18.6
      Mean ± SD.
      SI: 116.5 ± 29.4
      Mean ± SD.


      MI: 146.1 ± 30.1
      Mean ± SD.
      SI: 121.2 ± 26.7
      Mean ± SD.


      MI: 156.3 ± 25.6
      Mean ± SD.
      SI: 128.6 ± 29.3
      Mean ± SD.


      MI: 161.6 ± 22.7
      Mean ± SD.
      CI, confidence interval; IA, intra-articular; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection.
      Mean with 95% CI.
      Mean ± SD.
      Appendix Table 3Flexion, Reported as the Mean Only, Mean With 95% CI, or Mean ± SD
      AuthorFlexion
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      IA: 108.485
      Mean (extracted from graphs).


      SA: 106.01
      Mean (extracted from graphs).


      IA+SA: 104.154
      Mean (extracted from graphs).
      IA: 130.669
      Mean (extracted from graphs).


      SA: 131.023
      Mean (extracted from graphs).


      IA+SA: 133.586
      Mean (extracted from graphs).
      IA: 147.02
      Mean (extracted from graphs).


      SA: 143.043
      Mean (extracted from graphs).


      IA+SA: 143.838
      Mean (extracted from graphs).
      IA: 151.263
      Mean (extracted from graphs).


      SA: 144.545
      Mean (extracted from graphs).


      IA+SA: 145.96
      Mean (extracted from graphs).
      IA: 160.101
      Mean (extracted from graphs).


      SA: 156.301
      Mean (extracted from graphs).


      IA+SA: 156.212
      Mean (extracted from graphs).
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      IA: 91.0 (81.1-100.8)
      Mean with 95% CI.


      Combined group: 100.6 (92.3-109.0)
      Mean with 95% CI.
      IA: 109.8 (103.3-116.3)
      Mean with 95% CI.


      Combined group: 110.2 (103.6-116.9)
      Mean with 95% CI.
      IA: 120.6 (111.3-129.9)
      Mean with 95% CI.


      Combined group: 123.8 (114.4-133.2)
      Mean with 95% CI.
      IA: 133.1 (123.0-143.3)
      Mean with 95% CI.


      Combined group: 125.8 (115.5-136.1)
      Mean with 95% CI.
      IA: 145.9 (135.7-156.0)
      Mean with 95% CI.


      Combined group: 135.2 (125.0-145.5)
      Mean with 95% CI.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 116.9 ± 21.6
      Mean ± SD.


      SA: 112.2 ± 22.1
      Mean ± SD.


      IA+SA: 115.7 ± 20.1
      Mean ± SD.
      IA: 150.5 ± 19.3
      Mean ± SD.


      SA: 132.2 ± 26.4
      Mean ± SD.


      IA+SA: 153.5 ± 14.4
      Mean ± SD.
      IA: 158.8 ± 13.7
      Mean ± SD.


      SA: 145.4 ± 22.7
      Mean ± SD.


      IA+SA: 159.2 ± 11.6
      Mean ± SD.
      IA: 159.4 ± 16.1
      Mean ± SD.


      SA: 148.1 ± 20.7
      Mean ± SD.


      IA+SA: 159.7 ± 11.6
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      SI: 88.4 ± 11.7
      Mean ± SD.


      MI: 80.4 ± 19.8
      Mean ± SD.
      SI: 129.2 ± 22.2
      Mean ± SD.


      MI: 154.1 ± 21.6
      Mean ± SD.
      SI: 133.3 ± 21.5
      Mean ± SD.


      MI: 161.8 ± 19.2
      Mean ± SD.
      SI: 139.8 ± 29
      Mean ± SD.


      MI: 166.7 ± 15.7
      Mean ± SD.
      CI, confidence interval; IA, intra-articular; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection.
      Mean (extracted from graphs).
      Mean with 95% CI.
      Mean ± SD.
      Appendix Table 4External Rotation, Reported as the Mean Only, Mean With 95% CI, or Mean ± SD
      AuthorExternal rotation
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      IA: 31.0877
      Mean only (extracted from graphs).


      SA: 33.9649
      Mean only (extracted from graphs).


      IA+SA: 29.7544
      Mean only (extracted from graphs).
      IA: 46.0351
      Mean only (extracted from graphs).


      SA: 44.0702
      Mean only (extracted from graphs).


      IA+SA: 48.1404
      Mean only (extracted from graphs).
      IA: 57.8246
      Mean only (extracted from graphs).


      SA: 53.9649
      Mean only (extracted from graphs).


      IA+SA: 60.0702
      Mean only (extracted from graphs).
      IA: 60.2807
      Mean only (extracted from graphs).


      SA: 56.0702
      Mean only (extracted from graphs).


      IA+SA: 62.0351
      Mean only (extracted from graphs).
      IA: 64.1404
      Mean only (extracted from graphs).


      SA: 60.9123
      Mean only (extracted from graphs).


      IA+SA: 67.9298
      Mean only (extracted from graphs).
      Prestgaard et al.
      • Prestgaard T.
      • Wormgoor M.E.A.
      • Haugen S.
      • Harstad H.
      • Mowinckel P.
      • Brox J.I.
      Ultrasound-guided intra-articular and rotator interval corticosteroid injections in adhesive capsulitis of the shoulder: A double-blind, sham-controlled randomized study.
      IA: 15.8 (12.0-19.7)
      Mean with 95% CI.


      Combined group: 21.9 (18.2-25.6)
      Mean with 95% CI.
      IA: 25.3 (22.1-28.5)
      Mean with 95% CI.


      Combined group: 23.6 (20.2-27.0)
      Mean with 95% CI.
      IA: 29.5 (26.2-32.9)
      Mean with 95% CI.


      Combined group: 26.1 (22.7-296)
      Mean with 95% CI.
      IA: 36.4 (32.0-40.8)
      Mean with 95% CI.


      Combined group: 31.1 (26.6-35.6)
      Mean with 95% CI.
      IA: 36.7 (31.5-41.8)
      Mean with 95% CI.


      Combined group: 35.1 (29.8-40.4)
      Mean with 95% CI.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 34.4 ± 15.7
      Mean ± SD.


      SA: 32.6 ± 10.2
      Mean ± SD.


      IA+SA: 34.8 ± 14.1
      Mean ± SD.
      IA: 57.2 ± 13.6
      Mean ± SD.


      SA: 44.6 ± 14.6
      Mean ± SD.


      IA+SA:60.4 ± 11.4
      Mean ± SD.
      IA: 64.6 ± 10.8
      Mean ± SD.


      SA: 53.6 ± 16.6
      Mean ± SD.


      IA+SA: 67.8 ± 11.1
      Mean ± SD.
      IA: 64.4 ± 11.3
      Mean ± SD.


      SA: 54.7 ± 16.9
      Mean ± SD.


      IA+SA: 67.2 ± 12.6
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      SI :9.7 ± 8.3
      Mean ± SD.


      MI: 10.1 ± 9.7
      Mean ± SD.
      SI: 41.6 ± 12.9
      Mean ± SD.


      MI: 56.1 ± 9.4
      Mean ± SD.
      SI: 42.3 ± 13.5
      Mean ± SD.


      MI: 59.9 ± 6
      Mean ± SD.
      SI: 44.5 ± 12.8
      Mean ± SD.


      MI: 62.1 ± 6.5
      Mean ± SD.
      CI, confidence interval; IA, intra-articular; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection.
      Mean only (extracted from graphs).
      Mean with 95% CI.
      Mean ± SD.
      Appendix Table 5Internal Rotation, Reported as the Mean ±SD
      AuthorInternal Rotation
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 30.3 ± 11.3
      Mean ± SD.


      SA: 31.7 ± 12.4
      Mean ± SD.


      IA+SA: 32.4 ± 14.1
      Mean ± SD.
      IA: 53.9 ± 13.9
      Mean ± SD.


      SA: 42.6 ± 13.8
      Mean ± SD.


      IA+SA: 59.2 ± 13.8
      Mean ± SD.
      IA: 61.1 ± 10.3
      Mean ± SD.


      SA: 50.6 ± 15.0
      Mean ± SD.


      IA+SA: 65.4 ± 11.9
      Mean ± SD.
      IA: 61.9 ± 13.9
      Mean ± SD.


      SA: 53.1 ± 15.5
      Mean ± SD.


      IA+SA: 65.1 ± 13.2
      Mean ± SD.
      Koraman et al.
      • Koraman E.
      • Turkmen I.
      • Uygur E.
      • Poyanlı O.
      A multisite injection is more effective than a single glenohumeral injection of corticosteroid in the treatment of primary frozen shoulder: A randomized controlled trial.
      SI: 7.4 ± 7.4
      Mean ± SD.


      MI: 8.4 ± 10.5
      Mean ± SD.
      SI: 40.5 ± 11.2
      Mean ± SD.


      MI: 56 ± 11.4
      Mean ± SD.
      SI: 42.9 ± 11.5
      Mean ± SD.


      MI: 59.7 ± 9.4
      Mean ± SD.
      SI: 45 ± 10.2
      Mean ± SD.


      MI: 61.7 ± 9
      Mean ± SD.
      CI, confidence interval; IA, intra-articular; MI, multisite injection; SA, subacromial; SD, standard deviation; SI, single injection.
      Mean ± SD.
      Appendix Table 6ASES Assessment Form Score, Reported as the Mean ± SE or Mean ± SD
      AuthorASES Assessment Form
      Baseline3-4 wk6-8 wk12-16 wk24-26 wk
      Shin et al.
      • Shin S.J.
      • Lee S.Y.
      Efficacies of corticosteroid injection at different sites of the shoulder for the treatment of adhesive capsulitis.
      IA: 42.6 ± 3.1
      Mean ± SE.


      SA: 38.8 ± 3.6
      Mean ± SE.


      IA+SA: 39.5 ± 2.6
      Mean ± SE.
      IA: 85.1 ± 3.1
      Mean ± SE.


      SA: 76.3 ± 3.4
      Mean ± SE.


      IA+SA: 85.6 ± 1.6
      Mean ± SE.
      IA: 86.4 ± 2.1
      Mean ± SE.


      SA: 81.9 ± 3.7
      Mean ± SE.


      IA+SA: 86.5 ± 1.9
      Mean ± SE.
      IA: 88.4 ± 2.9
      Mean ± SE.


      SA: 87.1 ± 3.2
      Mean ± SE.


      IA+SA: 90.7 ± 2.8
      Mean ± SE.
      IA: 91.1 ± 1.3
      Mean ± SE.


      SA: 89.4 ± 1.9
      Mean ± SE.


      IA+SA: 90.7 ± 1.6
      Mean ± SE.
      Cho et al.
      • Cho C.H.
      • Kim du H.
      • Bae K.C.
      • Lee D.
      • Kim K.
      Proper site of corticosteroid injection for the treatment of idiopathic frozen shoulder: Results from a randomized trial.
      IA: 31.2 ± 14.6
      Mean ± SD.
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