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Open or Arthroscopic Synovectomy Is the Preferred Management Option in Pigmented Villonodular Synovitis of the Hip Joint Without Evidence of Degeneration: A Systematic Review of 20 Studies

Open AccessPublished:August 17, 2022DOI:https://doi.org/10.1016/j.asmr.2022.06.008

      Purpose

      To provide an up-to-date systematic review on the treatment options for pigmented villonodular synovitis (PVNS) of the hip and provide a grade of recommendation using standardized systems.

      Methods

      A systematic search of PubMed, Embase, Web of Science, and The Cochrane Library from the date of inception of each database through December 4, 2021, was performed. Studies that described the outcomes of treatment of hip PVNS were identified. These outcomes were discussed and synthesized by three reviewers, and a grade of recommendation was assigned.

      Results

      Twenty studies were identified. Seven studies described arthroscopic synovectomy, eight studies described open synovectomy, nine studies described arthroplasty, and one study described osmic acid synoviorthesis. Synovectomy, either open or arthroscopic, had similar rates of disease recurrence. Hip arthroplasty had low rates of disease recurrence compared to synovectomy; however, it was associated with significant risk of aseptic loosening in the longer term.

      Conclusion

      Synovectomy, either open or arthroscopic based on surgeon preference, is favored in the treatment of hip PVNS if there is no evidence of joint space narrowing. Arthroplasty should be considered in cases with joint space narrowing or recurrence following joint preservation therapy. There is insufficient evidence to support synoviorthesis either as monotherapy or adjuvant therapy.

      Level of Evidence

      IV, systematic review of Level III and IV studies.

      Introduction

      Pigmented villonodular synovitis (PVNS) is a rare proliferative disorder of the synovium,
      • Chassaignac C.
      Cancer de la gaine des tendons.
      with a reported incidence of 1.8 per million person years in the United States of America.
      • Myers B.W.
      • Masi A.T.
      • Feigenbaum S.L.
      Pigmented villonodular synovitis and tenosynovitis: A clinical epidemiologic study of 166 cases and literature review.
      The knee joint is most commonly involved, followed by the hip joint, which accounts for 9 to 15% of cases.
      • Steinmetz S.
      • Rougemont A.L.
      • Peter R.
      Pigmented villonodular synovitis of the hip.
      ,
      • Gaubert J.M.A.
      • Verdie J.C.
      • Cheneau J.
      Les synovites villonodulaires hémopigmentées des grosses articulations.
      PVNS of the hip typically presents in young adults with chronic hip pain, swelling, or recurrent hemarthrosis; however, atypical symptoms, such as locking
      • Beyzadeoğlu T.
      • Çirci E.
      Locked hip joint: An uncommon presentation of localized pigmented villonodular synovitis.
      or compressive sciatic and femoral neuropathy
      • Aboulafia A.J.
      • Kaplan L.
      • Jelinek J.
      • et al.
      Neuropathy secondary to pigmented villonodular synovitis of the hip.
      have been reported. Previous literature demonstrated increased prevalence in Type 1 diabetics.
      • Badessi F.
      • Doria C.
      • Mosele G.R.
      • et al.
      Pigmented villonodular synovitis in type 1 diabetes mellitus: A cross-sectional study in Sardinian people.
      Although usually benign and monoarticular, case reports of polyarticular involvement,
      • Botez P.
      • Sirbu P.D.
      • Grierosu C.
      • et al.
      Adult multifocal pigmented villonodular synovitis-clinical review.
      as well as lung, abdominal, and vertebral metastases do exist.
      • Cosseddu F.
      • Shytaj S.
      • Sacchetti
      • et al.
      Malignant pigmented villonodular synovitis: A brief literature review and a case report.
      • Shinjo K.
      • Miyake N.
      • Takahashi Y.
      Malignant giant cell tumor of the tendon sheath: An autopsy report and review of the literature.
      • Li L.M.
      • Jeffery J.
      Exceptionally aggressive pigmented villonodular synovitis of the hip unresponsive to radiotherapy.
      The workup of patients with suspected hip PVNS involves careful history taking and examination, plain film radiography, and magnetic resonance imaging (MRI), and if suspicious, either an open or image-guided synovial biopsy.
      • Belair J.
      • McKee C.
      • Desai V.
      • et al.
      Diagnostic yield of image-guided synovial biopsy for intra-articular synovial lesions.
      The gold-standard diagnostic test for PVNS is histological, with hemosiderin-stained multinucleated giant cells and pigmented foam cells seen under high-power microscopy.
      • Steinmetz S.
      • Rougemont A.L.
      • Peter R.
      Pigmented villonodular synovitis of the hip.
      Depending on the extent of synovial involvement, PVNS can be classified into diffuse or nodular subtypes, with potential influence on the management options. Even when adequately managed, there is a propensity for recurrence. The recurrence rate is highly variable, ranging from 8% to 60%.
      • Sharma V.
      • Cheng E.Y.
      Outcomes after excision of pigmented villonodular synovitis of the knee.
      Despite the hip being the second most common location for PVNS, there is little consensus as to its management.
      • Startzman A.
      • Carreira D.
      • Collins D.
      A systematic literature review of synovial chondromatosis and pigmented villonodular synovitis of the hip.
      The purpose of this study was to provide an up-to-date systematic review on the treatment options for PVNS of the hip and provide a grade of recommendation using standardized systems.
      • Wright J.G.
      • Swiontkowski M.F.
      • Heckman J.D.
      Introducing levels of evidence to the journal.
      ,
      • Wright J.G.
      • Einhorn T.A.
      • Heckman J.D.
      Grades of recommendation.
      We hypothesize that hip preservation techniques should be used when there are minimal signs of arthritis, whereas arthroplasty should be used where there is significant arthritis.

      Methods

      This systematic review was performed on the basis of the recommendations of Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).
      • Page M.J.
      • McKenzie J.E.
      • Bossuyt P.M.
      • et al.
      The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.
      This systematic review protocol was registered with PROSPERO (Registration Number: CRD42022301017).
      We performed a systematic search of the literature across multiple databases, including PubMed, Embase, The Cochrane Library, and Web of Science, from the date of inception through December 4, 2021. For studies that described treatment strategies for patients with hip PVNS, both operative and nonoperative were included. The outcomes of interest were disease recurrence, functional scores, and complications. Exclusion criteria included research protocols, epidemiological studies, and studies that described pathologies that were unrelated to hip PVNS, studies describing associations or diagnostic modalities rather than treatment of hip PVNS, systematic or narrative reviews, and case series or studies with fewer than 5 patients with hip PVNS. Studies with less than 5 patients allocated to all treatment modalities were also excluded. Studies were not excluded on the basis of upon their published language or geographic location. Full-text articles not available in English were translated with the help of a translation service.
      A literature search using the following search terms and Boolean operators (“pigmented villonodular synovitis” OR “PVNS” OR “giant cell”) AND (“hip”). The title and abstracts were then screened by two reviewers (T.C. and K.W.) independently for relevance and consideration into a provisional list. Further to that, the provisional list would then be assessed independently by the two reviewers after reading the full text for potential inclusion. If there were any discrepancies, the two reviewers would meet with a third reviewer (M.B.) and reach a consensus as to which articles would be included.
      Data extraction was performed by the first reviewer and validated by the second reviewer (K.W.). Baseline characteristics of included studies, as well as the outcome measures, were collected. Analysis of the data was performed based upon three subheadings—joint preservation therapy, arthroplasty, and nonoperative modalities. On the basis of the evidence, a grade of recommendation was assigned on the basis of the recommendations by Wright et al.
      • Wright J.G.
      • Einhorn T.A.
      • Heckman J.D.
      Grades of recommendation.
      If a “C” level of evidence was to be assigned, we would then proceed to a subscale, whereby a subscript “f”, “a”, or “c” was applied. These subscripts denoted that the evidence was “for”, “against”, or “conflicted”, respectively.
      • Stevens M.S.
      • Legay D.A.
      • Glazebrook M.A.
      • et al.
      The evidence for hip arthroscopy: Grading the current indications.
      A description of this is shown in Table 1. Subjective synthesis was performed for each outcome of interest, with confidence intervals calculated using the Clopper-Pearson method,
      • Clopper C.J.
      • Pearson E.S.
      The use of confidence or fiducial limits illustrated in the case of the binomial.
      with a two-tailed 95% confidence interval utilized if the proportion was greater than 0% and a one-tailed 97.5% confidence interval utilized if the proportion was 0%. The results were then displayed as a Forest plot. Lastly, the methodological quality of studies included was assessed independently by both reviewers using the methodological index for nonrandomized studies (MINORS).
      • Slim K.
      • Nini E.
      • Forestier D.
      • et al.
      Methodological index for non-randomized studies (minors): development and validation of a new instrument.
      Table 1Grade of Recommendations
      GradeDescription
      A (Good)Level I studies with consistent findings
      B (Fair)Level II or III studies with consistent findings
      C (Poor)Level IV or V studies OR conflicting evidence
      CfMajority of studies supports the intervention
      CaMajority of studies against the intervention
      CiConflicting studies with no clear majority
      I (Insufficient)Insufficient evidence to make any recommendation

      Results

      Search Results

      Two thousand one hundred and seventy-nine studies were identified using the initial search strategy, of which 721 duplicates were removed. From the remaining 1,458 studies, a further 1,176 were excluded by screening the titles and abstracts. Full-text analysis was performed for 282 studies, for which 20 studies met our inclusion criteria. The result of our literature search is displayed in Fig 1. A short summary of the key features of study design is shown in Supplementary Table 1. There was significant diversity between studies with poor overall methodology.

      Hip Preservation Studies

      Fourteen studies described hip preservation (nonarthroplasty) surgical techniques in the management of hip PVNS, of which there were 7 studies that described arthroscopic techniques
      • Byrd J.W.
      • Jones K.S.
      • Maiers 2nd, G.P.
      Two to 10 Years' follow-up of arthroscopic management of pigmented villonodular synovitis in the hip: A case series.
      • Chen J.
      • Chen S.
      • Wu Z.
      • et al.
      Arthroscopic synovectomy and synoviorthesis for pigmented villonodular synovitis in hip.
      • Nazal M.R.
      • Stelzer J.W.
      • Parsa A.
      • et al.
      Pigmented villonodular synovitis of the hip managed with arthroscopic synovectomy: An analysis of 19 cases with up to 10-year follow-up.
      • Nazal M.R.
      • Gibbs J.S.
      • Abraham P.F.
      • et al.
      Mid-term results of arthroscopic synovectomy for pigmented villonodular synovitis of the hip.
      • Tang H.-C.
      • Sadakah M.
      • Wirries N.
      • et al.
      Outcomes of arthroscopic management for pigmented villonodular synovitis of the hip.
      • Willimon S.C.
      • Schrader T.
      • Perkins C.A.
      Arthroscopic management of pigmented villonodular synovitis of the hip in children and adolescents.
      • Xie G.P.
      • Jiang N.
      • Liang C.X.
      • et al.
      Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
      and 8 studies that described open techniques.
      • Xie G.P.
      • Jiang N.
      • Liang C.X.
      • et al.
      Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
      • Hufeland M.
      • Gesslein M.
      • Perka C.
      • et al.
      Long-term outcome of pigmented villonodular synovitis of the hip after joint preserving therapy.
      • Ota T.
      • Nishida Y.
      • Ikuta K.
      • et al.
      Tumor location and type affect local recurrence and joint damage in tenosynovial giant cell tumor: a multi-center study.
      • Schwartz H.S.
      • Unni K.K.
      • Pritchard D.J.
      Pigmented villonodular synovitis. A retrospective review of affected large joints.
      • Schroder J.
      • Hufeland M.
      • Schaser K.D.
      • et al.
      Joint preserving therapy for villonodular synovitis of the hip.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      • Moroni A.
      • Innao V.
      • Picci P.
      Pigmented villonodular synovitis of the hip. Study of 9 cases.
      One study described both open and arthroscopic techniques.
      • Xie G.P.
      • Jiang N.
      • Liang C.X.
      • et al.
      Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
      For studies describing arthroscopic techniques of synovectomy, two studies performed adjuvant synoviorthesis.
      • Chen J.
      • Chen S.
      • Wu Z.
      • et al.
      Arthroscopic synovectomy and synoviorthesis for pigmented villonodular synovitis in hip.
      ,
      • Tang H.-C.
      • Sadakah M.
      • Wirries N.
      • et al.
      Outcomes of arthroscopic management for pigmented villonodular synovitis of the hip.
      Most of these studies were case series, with a limited number of patients. In total, there were 95 patients managed with arthroscopic synovectomy included in our analysis, with individual studies recruiting between 5 and 32 patients. There was a large variation in the mean age of patients, ranging from 11 to 41 years old. For studies in which the gender of participants was available, there were equal numbers of male and female participants. In terms of the type of PVNS, four of the seven studies displayed this information, with 19 patients having diffuse disease and 25 patients having nodular disease. The largest case series was performed by Chen et al. and had 32 patients. In this series, arthroscopic resection of diseased synovium was performed with synoviorthesis performed at 5 weeks postoperatively.
      • Chen J.
      • Chen S.
      • Wu Z.
      • et al.
      Arthroscopic synovectomy and synoviorthesis for pigmented villonodular synovitis in hip.
      Unfortunately, the agent used for synoviorthesis and the frequency of injection were not clearly described. One of these series performed only arthroscopic synovectomies in pediatric patients.
      • Willimon S.C.
      • Schrader T.
      • Perkins C.A.
      Arthroscopic management of pigmented villonodular synovitis of the hip in children and adolescents.
      The recurrence rate in our included studies ranged between 0 and 7.69% (Fig 2). Four patients had recurrence, of which 2 of these patients had a repeat arthroscopic synovectomy, 1 patient had conversion to arthroplasty, and there was no information on the remaining patient. The follow-up period was variable, with six of the seven studies having a mean follow-up of greater than 24 months. A summary of included studies is displayed in Table 2.
      Figure thumbnail gr2
      Fig 2Forest plot for proportion of recurrence in arthroscopic synovectomy studies.
      Table 2Hip Preservation Studies
      Author (Year)Design (Level of Evidence)Number of HipsAdjuvant TherapyAge (Mean, Range)Gender (M/F)Type (Diffuse/Nodular)Final HHS (Mean ± SD)Recurrence Rate (%)NotesFollow-Up
      Arthroscopic Synovectomy
       Byrd et al. (2013)Case Series (IV)13None26.8 (14 – 46)9/4NSNS1/13 (7.69%)Improvement in HHS 27 ± 27Mean of 17 months (Range: 2 – 60 months)
       Chen et al. (2013)Case Series (IV)32Synoviorthesis at 5 weeks postop for 5–6 weeks41 (18 – 55)NSNSNS2/32 (6.25%)One patient who had recurrent disease had repeat therapy, whereas another had arthroplastyMinimum 24 months
       Nazal et al. (2019)Case Series (IV)16None37 (25–54)9/78/878.2 ± 10.60/16 (0%)Mean of 83 months (Range: 24–123 months)
       Nazal et al. (2020)Case Series (IV)14None32.696/85/974.08 ± 16.841/14 (7.14%)Patient with recurrence had repeat therapyMean of 79.9 months (SD 22.4 months)
       Tang et al. (2021)Case Series (IV)9Radiosynoviothesis (in 5 patients)24.3 (14 –44)2/75/494.6 ± 4.90/9 (0%)Mean of 55.8 months (range: 24 – 84 months)
       Willimon et al. (2018)Case Series (IV)5None11 (7 – 17)2/31/4NS0/5 (0%)All paediatric patientsMean of 31.8 months (Range: 12 – 63 months)
       Xie et al. (2015)Retrospective Cohort (III)6None32.07NSNSNS0/6 (0%)Median of 108 months
      Open Synovectomy
       Flipo et al. (1994)Retrospective Cohort (III)22Osmic acid synoviorthesis (in 2 cases)NSNSNSNSNSBad results in 7 cases

      4 patients had arthroplasty, 1 had synoviorthesis, 1 had repeat synovectomy and 1 had observation only
      Mean of 34 months (Range 4 – 94 months)
       Hufeland et al. (2018)Case Series (IV)5None19.2 (8 – 28)1/44/188.81/5 (20%)Patient with recurrence had arthroplastyMean of 96 months (Range 35 – 141 months)
       Moroni et al. (1983)Retrospective Cohort (III)6None23 (13 – 34)1/4NSNS0/6 (0%)Mean of 32 months (Range 6 – 96 months)
       Ota et al. (2021)Retrospective Cohort (III)7NoneNSNSNSNS0/7 (0%)Data was part of a larger studyMedian of 66 months
       Schwartz et al. (1988)Retrospective Cohort (III)7Unclear36.9 (17 – 59)NSNSNS0/7 (0%)Also had patients with arthroplastyUp to 25 years
       Schroder et al. (2012)Case Series (IV)5Radiosynoviothesis31 (15 – 65)NS4/1NS1/5 (20%)Patient with recurrence had arthroplastyMean of 32 months (Range 8 – 56 months
       Vastel et al. (2005)Retrospective Cohort (III)8None29.75 (23 – 41)5/3NSNS0/8 (0%)Also had patients with arthroplasty

      4 patients had arthroplasty for progression of arthritis
      Mean of 187.5 months
       Xie et al. (2015)Retrospective Cohort (III)37None32.07NSNSNS3/37 (8.11%)2 patients with recurrence had repeat therapy and remaining one had arthroplastyMedian of 108 months
      F, female; HHS, Harris hip score; M, male; NS, not stated; SD, standard deviation.
      Open synovectomy technique was employed by eight authors, of which one study performed adjuvant radiosynoviorthesis for 6–8 weeks postoperatively.
      • Schroder J.
      • Hufeland M.
      • Schaser K.D.
      • et al.
      Joint preserving therapy for villonodular synovitis of the hip.
      In our included studies, there was a total of 97 hips and the mean age of study participants ranged from 19.2 to 36.9 years old. The remaining demographical information was unfortunately poorly collated. Only two studies described the type of hip PVNS, in which the majority had diffuse disease. Individual studies included were a mixture of retrospective cohort studies and case series and had between 5 and 37 participants, giving a total of 69 patients. The largest series was performed by Xie et al., who performed a retrospective cohort analysis on 237 patients with PVNS, for which, 37 patients had hip PVNS managed with open synovectomy.
      • Xie G.P.
      • Jiang N.
      • Liang C.X.
      • et al.
      Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
      On the basis of the data we collected, the recurrence rate was between 0 and 20% (Fig 3). Five patients had recurrence, of which 3 of these patients were managed with arthroplasty, and the remaining two had repeat open synovectomy.
      Figure thumbnail gr3
      Fig 3Forest plot for proportion of recurrence in open synovectomy studies.
      Flipo et al. conducted a national survey of the management of hip PVNS in France, whereby open synovectomies were performed in 22 cases. Among these 22 cases, 12 patients received a total synovectomy only, 8 patients received a partial synovectomy only, one patient had a partial synovectomy with osmic acid synoviorthesis, and the remaining patient had a total synovectomy and osmic acid synoviorthesis. In their series, a good outcome was seen in 11 of the 13 total synovectomies, whereas this was reduced to 3 of the 9 partial synovectomies.
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      Concerningly, in one series by Vastel et al., half of the 8 patients who received open synovectomy had conversion to hip arthroplasty at the end of the study period (between 10 and 28 years) due to progression of arthritis.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      Three out of the four of these patients had evidence of early osteoarthritis. The mean follow-up was at least 5 years in almost all of the included studies. A summary of included studies is displayed in Table 2.
      In summary, there was poor-quality evidence to support either open or arthroscopic synovectomy, with most demonstrating reasonably low recurrence rates with either hip preservation techniques (Grade Cf). There was insufficient evidence to suggest whether arthroscopic synovectomy should be favored in nodular disease or vice versa (Grade 1). There was also insufficient evidence to support the use of adjuvant synoviorthesis (Grade 1).

      Hip Arthroplasty Studies

      Nine studies described the use of hip arthroplasty for management of hip PVNS,
      • Schwartz H.S.
      • Unni K.K.
      • Pritchard D.J.
      Pigmented villonodular synovitis. A retrospective review of affected large joints.
      ,
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      ,
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      ,
      • Ardeljan A.D.
      • Polisetty T.S.
      • Palmer J.R.
      • et al.
      Pigmented villonodular synovitis of the hip in patients undergoing total hip arthroplasty: A retrospective case-controlled analysis.
      • Elzohairy M.M.
      Pigmented villonodular synovitis managed by total synovectomy and cementless total hip arthroplasty.
      • Tibbo M.E.
      • Wyles C.C.
      • Rose P.S.
      • et al.
      Long-term outcome of hip arthroplasty in the setting of pigmented villonodular synovitis.
      • Verspoor F.G.
      • Hannink G.
      • Scholte A.
      • et al.
      Arthroplasty for tenosynovial giant cell tumors.
      • Xu C.
      • Chen J.-Y.
      • Guo H.
      • et al.
      Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: A case-control study with middle-term follow-up.
      • Yoo J.J.
      • Kwon Y.S.
      • Koo K.-H.
      • et al.
      Cementless total hip arthroplasty performed in patients with pigmented villonodular synovitis.
      of which 3 studies also described joint preservation techniques in separate cohorts.
      • Schwartz H.S.
      • Unni K.K.
      • Pritchard D.J.
      Pigmented villonodular synovitis. A retrospective review of affected large joints.
      ,
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      ,
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      In terms of study design, there was a mixture of case control, case series, and retrospective cohort studies. The mean age was less heterogeneous between studies, ranging from 34.8 to 41.4 years old. Most studies performed a total synovectomy to remove all diseased tissue. One study only performed this for patients with “active” disease, defined by the presence of proliferative synovial tissue and histologically confirmed PVNS.
      • Tibbo M.E.
      • Wyles C.C.
      • Rose P.S.
      • et al.
      Long-term outcome of hip arthroplasty in the setting of pigmented villonodular synovitis.
      In total, 1,350 joints were investigated, with a large variation in the number of participants in individual studies. Of the seven studies that described the gender of the participants, there was a predilection for males, with 812 males and 504 females. Six of these studies described the indication for arthroplasty, in which most of them was performed for joint space narrowing.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      ,
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      ,
      • Elzohairy M.M.
      Pigmented villonodular synovitis managed by total synovectomy and cementless total hip arthroplasty.
      ,
      • Xu C.
      • Chen J.-Y.
      • Guo H.
      • et al.
      Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: A case-control study with middle-term follow-up.
      ,
      • Yoo J.J.
      • Kwon Y.S.
      • Koo K.-H.
      • et al.
      Cementless total hip arthroplasty performed in patients with pigmented villonodular synovitis.
      One study by Verspoor et al. performed arthroplasty for three of its five included patients due to extensive disease.
      • Verspoor F.G.M.
      • Hannink G.
      • Scholte A.
      • et al.
      Arthroplasty for tenosynovial giant cell tumors 17 patients followed for 0.2 to 15 years.
      Six studies described if patients had prior treatment for PVNS, for which 26/76 (34.21%) patients had received some form of treatment for hip PVNS prior to attempting arthroplasty. These included 21 cases of synovectomy (7 arthroscopic, 8 open, 6 unspecified), one case of synovectomy followed by resurfacing hemiarthroplasty, 2 cases of acetabular hemiarthroplasties and 2 cases of acetabular bone grafts.
      The largest study we have included was a case control study by Ardeljan et al. of 1,240 participants with hip PVNS. The authors compared the outcomes of patients with hip PVNS undergoing arthroplasty with a general cohort. Of note, there was significantly increased odds of implant complications (aseptic loosening, revision, and prosthetic joint infection) at 2 years. These patients also had a longer length of stay and increased odds of 90-day all-cause readmission.
      • Ardeljan A.D.
      • Polisetty T.S.
      • Palmer J.R.
      • et al.
      Pigmented villonodular synovitis of the hip in patients undergoing total hip arthroplasty: A retrospective case-controlled analysis.
      Flipo et al. performed total hip arthroplasty in 13 patients and cup arthroplasty in 8 patients, for which the indication for total hip arthroplasty was joint destruction. Interestingly, poor outcomes were observed in half (4/8) of the cup arthroplasty patients, but none in the total hip arthroplasty group.
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      However, another study by Xu et al. used cementless hip arthroplasty with ceramic-on-ceramic bearing surfaces, due to the relatively younger ages of this patient cohort and the need to optimize component survivorship, demonstrated good survivorship in this small case series.
      • Xu C.
      • Chen J.-Y.
      • Guo H.
      • et al.
      Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: A case-control study with middle-term follow-up.
      In terms of overall outcomes, Harris Hip Score was reported in four studies with a mean improvement between 30 and 48.2 points. Recurrence rates were displayed in 7 studies, ranging from 0 to 20%, of which there were two cases of recurrence (Fig 4). Despite lower recurrence, aseptic loosening was reported between 0 and 48% of patients, necessitating revision (Fig 5). Three long-term follow-up studies by Schwartz et al. have demonstrated alarming rates of aseptic loosening of 4/13 (30.7%) at 25 years, 12/25 (48%) at 20 years and 2/8 (25%) at 14 years respectively.
      • Schwartz H.S.
      • Unni K.K.
      • Pritchard D.J.
      Pigmented villonodular synovitis. A retrospective review of affected large joints.
      ,
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      ,
      • Tibbo M.E.
      • Wyles C.C.
      • Rose P.S.
      • et al.
      Long-term outcome of hip arthroplasty in the setting of pigmented villonodular synovitis.
      In most of these studies, the revisions were in patients who received hip arthroplasty with conventional polyethylene, cup arthroplasty, or cemented total hip replacements of the Charnley era. There are insufficient long-term data on uncemented hips with ultra-high molecular weight polyethylene (UHMWPE) as liners, although few studies seem to suggest a better survival.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      ,
      • Yoo J.J.
      • Kwon Y.S.
      • Koo K.-H.
      • et al.
      Cementless total hip arthroplasty performed in patients with pigmented villonodular synovitis.
      A summary of included studies is shown in Table 3.
      Figure thumbnail gr4
      Fig 4Forest plot for proportion of recurrence in arthroplasty studies.
      Figure thumbnail gr5
      Fig 5Forest plot for proportion of aseptic loosening in arthroplasty studies.
      Table 3Hip Arthroplasty Studies
      Author (Year)Design (Level of Evidence)Number of HipsProsthesisAdjuvant TherapyAge (Mean, Range)Gender (M/F)IndicationPrior TreatmentImprovement in HHS (Mean)Recurrence Rate (%)Aseptic LooseningFollow-up
      Ardeljan et al. (2021)Case Control (III) with non-PVNS as control1240NSUnclearNS779/461NSNSNSNS28/1240 (2.26%)2 years
      Elzohairy et al. (2018)Case Series (IV)11Uncemented MOP (8)Total Synovectomy38.2 (30 – 50)6/5Lytic lesions with joint space narrowing in all patients0/1148.20/11 (0%)0/ 11 (0%)Mean of 7.2 years (5 – 10.5 years)
      Flipo et al. (1994)Retrospective Cohort (III)21Cup Arthroplasty (8)

      Unspecified Total (13)
      Total SynovectomyNSNSJoint destruction in total arthroplasty group0/21NSNS0/21 (0%)Mean of 34 months (Range 4 – 94 months)
      Schwartz et al. (1988)Case Series (IV)13NSTotal Synovectomy36.9 (17 – 59)NSNSUnclearNS0/13 (0%)4/13 (30.77%)Up to 25 years
      Tibbo et al. (2018)Case Series (IV)25Cemented (7)

      Uncemented (13)

      Hybrid Cemented Stem (3)

      Resurfacing (2)
      Synovectomy in 20 patients with active disease39 (16 – 67)9/16NS15/25300/25 (0%)12/25 (48%)Up to 20 years
      Vastel et al. (2005)Retrospective Cohort (III)8Cemented (4)

      Cup Arthroplasty (3)

      Monopolar (1)
      Total Synovectomy41.4 (24 – 61)4/4Joint space narrowing in 6/8 patients0/8NS1/8 (12.5%)2/8 (25%)Mean of 17.9 years
      Verspoor et al. (2016)Case Series (IV)5NSNS33.4 (16 – 49)3/2Extensive disease or arthritis3/5NS1/5 (20%)0/5 (0%)Mean of 10.3 years
      Xu et al. (2018)Case Control (III) with non-PVNS as control19Uncemented COC (19)Total Synovectomy35.2 (22 – 58)7/12Cystic erosions and joint space narrowing in all patients5/1943.90/19 (0%)1/19 (5.26%)Mean of 8.7 years
      Yoo et al. (2009)Case Series (IV)8Uncemented COC (3)

      Uncemented COP (2)
      Total Synovectomy34.8 (20 – 68)4/4Complete obliteration of joint space in 5/8 patients3/847.30/8 (0%)0/8 (0%)Mean of 8.9 years (Range 4.3 – 13.5 years)
      COC, ceramic-on-ceramic; COP, ceramic-on-polyethylene; F, female; HHS, Harris hip score; M, male; MOP, metal-on-polyethylene; NS, not stated.
      In summary, our analysis suggests that arthroplasty should be considered in patients with hip PVNS with evidence of joint space narrowing, or in cases of failed joint preservation therapies. Although there is a lower incidence of disease recurrence compared to hip preservation techniques, there is an increased risk of aseptic loosening. It is possible that with recent advancements in technology, such as the use of UHMWPE liners or ceramic-on-ceramic constructs, the risk of this may be less; however, there is a lack of long-term data.
      • Elzohairy M.M.
      Pigmented villonodular synovitis managed by total synovectomy and cementless total hip arthroplasty.
      ,
      • Xu C.
      • Chen J.-Y.
      • Guo H.
      • et al.
      Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: A case-control study with middle-term follow-up.
      ,
      • Yoo J.J.
      • Kwon Y.S.
      • Koo K.-H.
      • et al.
      Cementless total hip arthroplasty performed in patients with pigmented villonodular synovitis.
      Nevertheless, literature seems to support arthroplasty as a treatment modality in patients with evidence of significant hip degeneration, with adequate counselling on the risk and benefit (Grade Cf).

      Nonsurgical Techniques

      Only one study described nonsurgical techniques as monotherapy. Flipo et al. performed osmic acid synoviorthesis in 12 patients, of which 7 had a good outcome.
      • Flipo R.M.
      • Desvigne-Noulet M.C.
      • Cotten A.
      • et al.
      Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
      Four of their patients had a poor outcome, in which total synovectomy was performed in three cases, and repeat therapy was performed in one case. Radiosynoviothesis was described as adjuvant therapy in 2 studies to synovectomy;
      • Tang H.-C.
      • Sadakah M.
      • Wirries N.
      • et al.
      Outcomes of arthroscopic management for pigmented villonodular synovitis of the hip.
      ,
      • Schroder J.
      • Hufeland M.
      • Schaser K.D.
      • et al.
      Joint preserving therapy for villonodular synovitis of the hip.
      however, information on outcomes was only available for one study. In that study by Schroder et al., 1 of 5 patients who received open synovectomy with adjuvant radiosynoviothesis had recurrence.
      • Schroder J.
      • Hufeland M.
      • Schaser K.D.
      • et al.
      Joint preserving therapy for villonodular synovitis of the hip.
      In summary, there is insufficient evidence to recommend synoviorthesis either as monotherapy or adjuvant therapy (Grade 1). This recommendation reflects a lack of studies, rather than a lack of efficacy.

      Risk of Bias Analysis

      Risk of bias analysis was performed using the MINORS criteria. Of note, almost all studies did not perform prospective collection of data. However, most studies had a clearly stated aim, included consecutive patients, and had adequate follow-up. More than half of the studies had a less than 5% attrition rate at the conclusion of the study. The results of these studies are shown in Table 4.
      Table 4MINORS Scoring
      Ardeljan (2021)Byrd (2013)Chen (2013)Elzohairy (2018)Flipo (1994)Hufeland alet (2018)Moroni (1983)Nazal (2019)Nazal (2020)Ota (2021)Schroder (2012)Schwartz (1988)Tang (2021)Tibbo (2018)Vastel (2005)Verspoor (2016)Willimon (2018)Xie (2015)Xu (2018)Yoo (2009)
      Clearly Stated Aim22222212222222222222
      Inclusion of Consecutive Patients22221222222222222222
      Prospective Collection of Data00000000110002001112
      Appropriate Endpoints12222222222222222222
      Unbiased Assessment of Endpoints22222222222122222222
      Appropriate Follow-up Period11121112221112221122
      Loss to Follow-up Less Than 5%21221221212122222212
      Prospective Calculation of Sample Size00
      Adequate Control Group22
      Contemporary Groups22
      Baseline Equivalence of Groups22
      Adequate Statistical Analysis22

      Discussion

      The findings of our systematic review suggest that patients with hip PVNS should be evaluated for evidence of substantial arthritic changes using plain-film radiographs. If there is minimal to no degeneration of the joint space, we recommend hip preservation surgery with either an arthroscopic or open synovectomy, depending on resources available. If there is substantial destruction of the joint, arthroplasty can be considered. Patients should be counselled on the risk and benefits of arthroplasty, specifically, the lower risk of recurrence in arthroplasty, but also the risk of aseptic loosening of the prosthesis in the longer term. In cases of failed hip preservation surgery, arthroplasty may be considered as an alternative to repeat synovectomy. Our proposed evidence-based decision algorithm is displayed in Fig 6, and a summary of our recommendations is shown in Table 5.
      Table 5Summary of Recommendations
      RecommendationsGrade of Recommendation
      Synovectomy (open or arthroscopic) should be performed in the treatment of hip PVNS if joint preservation is desiredGrade Cf
      Insufficient evidence to support either open or arthroscopic synovectomy in the treatment of nodular disease versus diffuse disease, and vice versa.Grade 1
      Arthroplasty should be considered in patients with hip PVNS with joint space narrowingGrade Cf
      Arthroplasty should be considered in patients with hip PVNS with failed joint preservation therapyGrade Cf
      Insufficient evidence to support synoviorthesis either as monotherapy or adjuvant therapyGrade 1
      The goal of synovectomy is to ensure that all diseased tissue is removed to minimize the risk of recurrence. Although it could be argued that in cases of diffuse PVNS, synovectomy is best performed as an open procedure, the studies that we have included have not been able to substantiate this claim. Additionally, there is insufficient evidence to support adjuvant synoviorthesis. In cases of arthroscopy, the recommendation is to perform a T-capsular arthrotomy to increase the mobility of arthroscopic instruments, hence, allowing adequate resection of diseased tissue.
      • Lee S.
      • Haro M.S.
      • Riff A.
      • et al.
      Arthroscopic technique for the treatment of pigmented villonodular synovitis of the hip.
      Radiosynoviothesis or chemosynoviothesis has yet to be adequately investigated in the context of hip PVNS. There is evidence, however, to support the use of adjuvant radiosynoviothesis in patients with knee PVNS.
      • Nassar W.A.
      • Bassiony A.A.
      • Elghazaly H.A.
      Treatment of diffuse pigmented villonodular synovitis of the knee with combined surgical and radiosynovectomy.
      ,
      • Atilgan H.I.
      • Sadic M.
      • Koca G.
      • et al.
      Radiosynovectomy application after arthroscopic surgery on the hip joint.
      Theoretically, in diffuse cases, there may be a role for adjuvant radiosynoviothesis or chemosynoviothesis as safe surgical dislocation may risk inadvertent damage to the medial femoral circumflex artery and, hence, leading to avascular necrosis.
      • Massè A.
      • Aprato A.
      • Alluto C.
      • et al.
      Surgical hip dislocation is a reliable approach for treatment of femoral head fractures.
      • Keel M.
      • Eid K.
      • Isler B.
      • et al.
      The role of surgical hip dislocation in the treatment of acetabular and femoral head fractures.
      • Zlotorowicz M.
      • Czubak J.
      • Caban A.
      • et al.
      The blood supply to the femoral head after posterior fracture/dislocation of the hip, assessed by CT angiography.
      Ganz et al. have previously demonstrated that anterior dislocation with trochanteric flip osteotomy mitigated the risk of femoral head osteonecrosis.
      • Ganz R.
      • Gill T.J.
      • Gautier E.
      • et al.
      Surgical dislocation of the adult hip.
      This technique was used by Vastel et al.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      and Hufeland et. al.,
      • Hufeland M.
      • Gesslein M.
      • Perka C.
      • et al.
      Long-term outcome of pigmented villonodular synovitis of the hip after joint preserving therapy.
      with 8 and 5 patients respectively. Of these 13 patients, none developed femoral head osteonecrosis, with only one patient experiencing recurrence. There were limited studies on nonoperative measures, such as radiosynoviothesis, external beam radiotherapy, and systemic therapies for the management of hip PVNS. This is despite good evidence supporting the use of CSF-1 receptor inhibitors, such as nilotinib and pexidartinib for PVNS that is not amenable to surgical resection.
      • Gelderblom H.
      • Cropet C.
      • Chevreau C.
      • et al.
      Nilotinib in locally advanced pigmented villonodular synovitis: A multicentre, open-label, single-arm, phase 2 trial.
      ,
      • Tap W.D.
      • Gelderblom H.
      • Palmerini E.
      • et al.
      Pexidartinib versus placebo for advanced tenosynovial giant cell tumour (ENLIVEN): A randomised phase 3 trial.
      Degenerative disease of the affected joint is not uncommon in patients with hip PVNS. Although the exact mechanism is unknown, evidence of bony lesions on radiographs in patients presenting with hip PVNS has shown to be significantly higher, at 89%, when compared to PVNS of other joints.
      • Nishida Y.
      • Tsukushi S.
      • Nakashima H.
      • et al.
      Osteochondral destruction in pigmented villonodular synovitis during the clinical course.
      The median time of diagnosis from the onset of disease has been shown to be 18 months.
      • Xie G.P.
      • Jiang N.
      • Liang C.X.
      • et al.
      Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
      As PVNS expands, pain and swelling lead to range of motion limitations.
      • Brahmi M.
      • Vinceneux A.
      • Cassier P.A.
      Current systemic treatment options for tenosynovial giant cell tumor/pigmented villonodular synovitis: Targeting the CSF1/CSF1R axis.
      Histological analysis demonstrates mononuclear cells, macrophages with extensive hemosiderin stores, and multinucleated osteoclast-type giant cells. As repeated bleeding into the joint occurs, hemoglobin breaks down and deposits in the surrounding tissues.
      • Al Farii H.
      • Zhou S.
      • Turcotte R.
      The surgical outcome and recurrence rate of tenosynovial giant cell tumor in the elbow: A literature review.
      The resulting hemosiderin-laden parenchyma leads to further joint destruction in a slow manner—as in hemophilia.
      • Frassica F.J.
      • Bhimani M.A.
      • McCarthy E.F.
      • et al.
      Pigmented villonodular synovitis of the hip and knee.
      ,
      • Houdek M.T.
      • Scorianz M.
      • Wyles C.C.
      • et al.
      Long-term outcome of knee arthroplasty in the setting of pigmented villonodular synovitis.
      In addition, PVNS has been shown to have neoplastic components. Translocations of chromosome 1p13 are present in the majority of PVNS cases with the endpoint effect of overexpressing colony-stimulating factor-1 (CSF-1). As CSF-1 becomes overexpressed, clusters of aberrant cells form to create focal areas of soft tissue hyperplasia in the synovial cells lining joints.
      • West R.B.
      • Rubin B.P.
      • Miller M.A.
      • et al.
      A landscape effect in tenosynovial giant-cell tumor from activation of CSF1 expression by a translocation in a minority of tumor cells.
      However, the proportion of patients with PVNS who have destructive disease requiring treatment is unknown.
      In patients with advanced joint destruction and PVNS, it may be better if arthroplasty is performed. The series by Vastel et al. had demonstrated progression of arthritis in half of the synovectomy group, necessitating arthroplasty, despite no evidence of disease recurrence. Most of these patients had a degree of joint degeneration prior to synovectomy.
      • Vastel L.
      • Lambert P.
      • Charrois O.
      • et al.
      Surgical treatment of pigmented villonodular synovitis of the hip.
      In terms of prosthesis, there is insufficient evidence at present to support either cemented or uncemented implants, or specific bearing surfaces. The increased rate of aseptic loosening was previously thought to be due to the features of older-generation implants. It is hoped that newer uncemented implants would allow bony ingrowth, alongside improved bearing surfaces, such as ceramic or highly cross-linked polyethylene would generate less debris and, hence, reduce the risk of loosening.

      Limitations

      There are several limitations in our study. First, all of the included studies were retrospective case series, case control, or cohort studies. Such studies of PVNS of the hip are relatively uncommon. However, these studies lack random allocation to study groups, which, in turn, increases the risk of selection bias. The diverse nature of included studies, in combination with poor research methodologies, precluded a formal meta-analysis. Instead, we have displayed our results as Forest plots with summary estimates removed, and we have avoided pooling of outcomes in our discussion, in line with recommended practice.
      • Harris J.D.
      • Brand J.C.
      • Cote M.P.
      • et al.
      Research pearls: The significance of statistics and perils of pooling. Part 3: Pearls and pitfalls of meta-analyses and systematic reviews.
      With such small cohorts, it is likely that surgeon experience or preference may have played a role in the allocation of one intervention over the other. Second, there may have been publication bias. To reduce the risk of publication bias, we extended our search to wider databases, such as the Web of Science. Third, some of our included studies had a poor display of demographic data, which diminished our ability to perform more detailed analysis. A few older studies utilized cup arthroplasty, as opposed to conventional hip arthroplasty, which may have led to increased rates of adverse outcomes. Lastly, a major limitation was that there was a single large study by Ardeljan et al.,
      • Ardeljan A.D.
      • Polisetty T.S.
      • Palmer J.R.
      • et al.
      Pigmented villonodular synovitis of the hip in patients undergoing total hip arthroplasty: A retrospective case-controlled analysis.
      containing 86% of the patients in this review, which had the potential to outweigh other studies. This speaks to the rarity of the condition being investigated.

      Conclusions

      Synovectomy, either open or arthroscopic based on surgeon preference, is favored in the treatment of hip PVNS if there is no evidence of joint space narrowing. Arthroplasty should be considered in cases with joint space narrowing or recurrence following joint preservation therapy. There is insufficient evidence to support synoviorthesis either as monotherapy or adjuvant therapy.

      Supplementary Data

      References

        • Chassaignac C.
        Cancer de la gaine des tendons.
        Gaz Hop Cive Milit. 1852; 47: 185-186
        • Myers B.W.
        • Masi A.T.
        • Feigenbaum S.L.
        Pigmented villonodular synovitis and tenosynovitis: A clinical epidemiologic study of 166 cases and literature review.
        Medicine. 1980; 59: 223-238
        • Steinmetz S.
        • Rougemont A.L.
        • Peter R.
        Pigmented villonodular synovitis of the hip.
        EFORT Open Rev. 2016; 1: 260-266
        • Gaubert J.M.A.
        • Verdie J.C.
        • Cheneau J.
        Les synovites villonodulaires hémopigmentées des grosses articulations.
        Rev Chir Orthop. 1974; 60: 265-268
        • Beyzadeoğlu T.
        • Çirci E.
        Locked hip joint: An uncommon presentation of localized pigmented villonodular synovitis.
        Acta Orthop Traumatol Turc. 2016; 50: 379-381
        • Aboulafia A.J.
        • Kaplan L.
        • Jelinek J.
        • et al.
        Neuropathy secondary to pigmented villonodular synovitis of the hip.
        Clin Orthop Relat Res. 1996; : 174-180
        • Badessi F.
        • Doria C.
        • Mosele G.R.
        • et al.
        Pigmented villonodular synovitis in type 1 diabetes mellitus: A cross-sectional study in Sardinian people.
        Int J Clin Rheumatol. 2016; 11: 15-20
        • Botez P.
        • Sirbu P.D.
        • Grierosu C.
        • et al.
        Adult multifocal pigmented villonodular synovitis-clinical review.
        Int Orthop. 2013; 37: 729-733
        • Cosseddu F.
        • Shytaj S.
        • Sacchetti
        • et al.
        Malignant pigmented villonodular synovitis: A brief literature review and a case report.
        Clin Cases Min Bone Metab. 2019; 16: 181-185
        • Shinjo K.
        • Miyake N.
        • Takahashi Y.
        Malignant giant cell tumor of the tendon sheath: An autopsy report and review of the literature.
        Jpn J Clin Oncol. 1993; 23: 317-324
        • Li L.M.
        • Jeffery J.
        Exceptionally aggressive pigmented villonodular synovitis of the hip unresponsive to radiotherapy.
        J Bone Joint Surg Br. 2011; 93: 995-997
        • Belair J.
        • McKee C.
        • Desai V.
        • et al.
        Diagnostic yield of image-guided synovial biopsy for intra-articular synovial lesions.
        Skel Radiol. 2019; 48: 486-487
        • Sharma V.
        • Cheng E.Y.
        Outcomes after excision of pigmented villonodular synovitis of the knee.
        Clin Orthop Rel Res. 2009; 467: 2852-2858
        • Startzman A.
        • Carreira D.
        • Collins D.
        A systematic literature review of synovial chondromatosis and pigmented villonodular synovitis of the hip.
        Physician Sportsm. 2016; 44: 425-431
        • Wright J.G.
        • Swiontkowski M.F.
        • Heckman J.D.
        Introducing levels of evidence to the journal.
        J Bone Joint Surg Am. 2003; 85: 1-3
        • Wright J.G.
        • Einhorn T.A.
        • Heckman J.D.
        Grades of recommendation.
        J Bone Joint Surg Am. 2005; 87: 1909-1910
        • Page M.J.
        • McKenzie J.E.
        • Bossuyt P.M.
        • et al.
        The PRISMA 2020 statement: An updated guideline for reporting systematic reviews.
        BMJ. 2021; 372: n71
        • Stevens M.S.
        • Legay D.A.
        • Glazebrook M.A.
        • et al.
        The evidence for hip arthroscopy: Grading the current indications.
        Arthroscopy. 2010; 26: 1370-1383
        • Clopper C.J.
        • Pearson E.S.
        The use of confidence or fiducial limits illustrated in the case of the binomial.
        Biometrika. 1934; 26: 404-413
        • Slim K.
        • Nini E.
        • Forestier D.
        • et al.
        Methodological index for non-randomized studies (minors): development and validation of a new instrument.
        ANZ J Surg. 2003; 73: 712-716
        • Byrd J.W.
        • Jones K.S.
        • Maiers 2nd, G.P.
        Two to 10 Years' follow-up of arthroscopic management of pigmented villonodular synovitis in the hip: A case series.
        Arthroscopy. 2013; 29: 1783-1787
        • Chen J.
        • Chen S.
        • Wu Z.
        • et al.
        Arthroscopic synovectomy and synoviorthesis for pigmented villonodular synovitis in hip.
        Arthroscopy. 2013; 29: e124
        • Nazal M.R.
        • Stelzer J.W.
        • Parsa A.
        • et al.
        Pigmented villonodular synovitis of the hip managed with arthroscopic synovectomy: An analysis of 19 cases with up to 10-year follow-up.
        Orthop J Sports Med. 2019; 72325967119S00413
        • Nazal M.R.
        • Gibbs J.S.
        • Abraham P.F.
        • et al.
        Mid-term results of arthroscopic synovectomy for pigmented villonodular synovitis of the hip.
        Arthroscopy. 2020; 36: 1587-1598
        • Tang H.-C.
        • Sadakah M.
        • Wirries N.
        • et al.
        Outcomes of arthroscopic management for pigmented villonodular synovitis of the hip.
        [published online November 22, 2021]. Arch Orthop Trauma Surg. 2021; (doi:10.1007/s00402-021-04242-y)
        • Willimon S.C.
        • Schrader T.
        • Perkins C.A.
        Arthroscopic management of pigmented villonodular synovitis of the hip in children and adolescents.
        Orthop J Sports Med. 2018; 62325967118763118
        • Xie G.P.
        • Jiang N.
        • Liang C.X.
        • et al.
        Pigmented villonodular synovitis: A retrospective multicenter study of 237 cases.
        PLoS One. 2015; 10e0121451
        • Hufeland M.
        • Gesslein M.
        • Perka C.
        • et al.
        Long-term outcome of pigmented villonodular synovitis of the hip after joint preserving therapy.
        Arch Orthop Trauma Surg. 2018; 138: 471-477
        • Ota T.
        • Nishida Y.
        • Ikuta K.
        • et al.
        Tumor location and type affect local recurrence and joint damage in tenosynovial giant cell tumor: a multi-center study.
        Sci Rep. 2021; 1117384
        • Schwartz H.S.
        • Unni K.K.
        • Pritchard D.J.
        Pigmented villonodular synovitis. A retrospective review of affected large joints.
        Clin Orthop Relat Res. 1989; 247: 243-255
        • Schroder J.
        • Hufeland M.
        • Schaser K.D.
        • et al.
        Joint preserving therapy for villonodular synovitis of the hip.
        HIP Int. 2012; 22: 430
        • Vastel L.
        • Lambert P.
        • Charrois O.
        • et al.
        Surgical treatment of pigmented villonodular synovitis of the hip.
        J Bone Jt Surg Ser A. 2005; 87: 1019-1024
        • Flipo R.M.
        • Desvigne-Noulet M.C.
        • Cotten A.
        • et al.
        Pigmented villonodular synovitis of the hip. Results of a national survey apropos of 58 cases.
        Rev Rhum (Ed francaise: 1993). 1994; 61: 85-95
        • Moroni A.
        • Innao V.
        • Picci P.
        Pigmented villonodular synovitis of the hip. Study of 9 cases.
        Ital J Orthop Traumatol. 1983; 9: 331-337
        • Ardeljan A.D.
        • Polisetty T.S.
        • Palmer J.R.
        • et al.
        Pigmented villonodular synovitis of the hip in patients undergoing total hip arthroplasty: A retrospective case-controlled analysis.
        J Arthroplasty. 2021; 36: 1018-1022
        • Elzohairy M.M.
        Pigmented villonodular synovitis managed by total synovectomy and cementless total hip arthroplasty.
        Eur J Orthop Surg Traumatol. 2018; 28: 1375-1380
        • Tibbo M.E.
        • Wyles C.C.
        • Rose P.S.
        • et al.
        Long-term outcome of hip arthroplasty in the setting of pigmented villonodular synovitis.
        J Arthroplasty. 2018; 33: 1467-1471
        • Verspoor F.G.
        • Hannink G.
        • Scholte A.
        • et al.
        Arthroplasty for tenosynovial giant cell tumors.
        Acta Orthop. 2016; 87: 497-503
        • Xu C.
        • Chen J.-Y.
        • Guo H.
        • et al.
        Pigmented villonodular synovitis does not influence the outcome following cementless total hip arthroplasty using ceramic-on-ceramic articulation: A case-control study with middle-term follow-up.
        J Orthop Surg Res. 2018; 13: 294
        • Yoo J.J.
        • Kwon Y.S.
        • Koo K.-H.
        • et al.
        Cementless total hip arthroplasty performed in patients with pigmented villonodular synovitis.
        J Arthroplasty. 2010; 25: 552-557
        • Verspoor F.G.M.
        • Hannink G.
        • Scholte A.
        • et al.
        Arthroplasty for tenosynovial giant cell tumors 17 patients followed for 0.2 to 15 years.
        Acta Orthop. 2016; 87: 497-503
        • Lee S.
        • Haro M.S.
        • Riff A.
        • et al.
        Arthroscopic technique for the treatment of pigmented villonodular synovitis of the hip.
        Arthrosc Tech. 2015; 4: e41-e46
        • Nassar W.A.
        • Bassiony A.A.
        • Elghazaly H.A.
        Treatment of diffuse pigmented villonodular synovitis of the knee with combined surgical and radiosynovectomy.
        HSS J. 2009; 5: 19-23
        • Atilgan H.I.
        • Sadic M.
        • Koca G.
        • et al.
        Radiosynovectomy application after arthroscopic surgery on the hip joint.
        Eur J Nucl Med Mol Imag. 2015; 42: S748-S749
        • Massè A.
        • Aprato A.
        • Alluto C.
        • et al.
        Surgical hip dislocation is a reliable approach for treatment of femoral head fractures.
        Clin Orthop Rel Res. 2015; 473: 3744-3751
        • Keel M.
        • Eid K.
        • Isler B.
        • et al.
        The role of surgical hip dislocation in the treatment of acetabular and femoral head fractures.
        Eur J Trauma. 2005; 31: 138-147
        • Zlotorowicz M.
        • Czubak J.
        • Caban A.
        • et al.
        The blood supply to the femoral head after posterior fracture/dislocation of the hip, assessed by CT angiography.
        Bone Jt J. 2013; 95-B: 1453-1457
        • Ganz R.
        • Gill T.J.
        • Gautier E.
        • et al.
        Surgical dislocation of the adult hip.
        J Bone Jt Surg. 2001; 83-B: 1119-1124
        • Gelderblom H.
        • Cropet C.
        • Chevreau C.
        • et al.
        Nilotinib in locally advanced pigmented villonodular synovitis: A multicentre, open-label, single-arm, phase 2 trial.
        Lancet Oncol. 2018; 19: 639-648
        • Tap W.D.
        • Gelderblom H.
        • Palmerini E.
        • et al.
        Pexidartinib versus placebo for advanced tenosynovial giant cell tumour (ENLIVEN): A randomised phase 3 trial.
        Lancet. 2019; 394: 478-487
        • Nishida Y.
        • Tsukushi S.
        • Nakashima H.
        • et al.
        Osteochondral destruction in pigmented villonodular synovitis during the clinical course.
        J Rheumatol. 2012; 39: 345-351
        • Brahmi M.
        • Vinceneux A.
        • Cassier P.A.
        Current systemic treatment options for tenosynovial giant cell tumor/pigmented villonodular synovitis: Targeting the CSF1/CSF1R axis.
        Curr Treat Options Oncol. 2016; 17: 10
        • Al Farii H.
        • Zhou S.
        • Turcotte R.
        The surgical outcome and recurrence rate of tenosynovial giant cell tumor in the elbow: A literature review.
        J Shoulder Elbow Surg. 2019; 28: 1835-1840
        • Frassica F.J.
        • Bhimani M.A.
        • McCarthy E.F.
        • et al.
        Pigmented villonodular synovitis of the hip and knee.
        Am Fam Physician. 1999; 60: 1404-1410
        • Houdek M.T.
        • Scorianz M.
        • Wyles C.C.
        • et al.
        Long-term outcome of knee arthroplasty in the setting of pigmented villonodular synovitis.
        Knee. 2017; 24: 851-855
        • West R.B.
        • Rubin B.P.
        • Miller M.A.
        • et al.
        A landscape effect in tenosynovial giant-cell tumor from activation of CSF1 expression by a translocation in a minority of tumor cells.
        Proc Natl Acad Sci USA. 2006; 103: 690-695
        • Harris J.D.
        • Brand J.C.
        • Cote M.P.
        • et al.
        Research pearls: The significance of statistics and perils of pooling. Part 3: Pearls and pitfalls of meta-analyses and systematic reviews.
        Arthroscopy. 2017; 33: 1594-1602