Skip to content

Giant Cell Tumour of Tendon Sheath

Giant cell tumour of tendon sheath (a.k.a. tenosynovial giant cell tumour, localised pigmented villonodular synovitis).

Overview

Giant cell tumour of tendon sheath is a common benign tumour of the hand [1]. Giant cell tumors of the synovial sheaths in the hand are benign lesions [2]. Pigmented villonoid synovitis and giant-cell tumor of tendon sheath are benign synovial neoplasms [3]. Reports in the paediatric population are rare, including a case in a 4-year-old boy believed to be the youngest reported [1].

Recurrence is the primary risk associated with these lesions [2]. Pigmented villonoid synovitis and giant-cell tumor of tendon sheath have the potential for local recurrence [3]. Tenosynovial giant cell tumors and pigmented villonodular synovitis are related entities [4]. Complete surgical resection is the treatment of choice for most patients with tenosynovial giant cell tumors [4]. Diffuse disease in tenosynovial giant cell tumors presents challenges due to high recurrence rates [4]. Multifocal, recurrent, bilateral giant cell tumor of the tendon sheath and pigmented villonodular synovitis involving both upper and lower extremities is a rare instance [5].

The pathogenesis of pigmented villonoid synovitis remains unclear [6]. The optimum treatment of pigmented villonoid synovitis remains unclear [6]. Uncertainties regarding pigmented villonoid synovitis persist due to the rarity of cases [6]. Uncertainties regarding pigmented villonoid synovitis persist due to varying reporting details [6]. Uncertainties regarding pigmented villonoid synovitis persist due to lack of long-term follow-up in most series [6]. More prospective well-designed studies including a large number of cases are necessary to identify giant cell tumours prone to recurrence [24]. More prospective well-designed studies including a large number of cases are necessary to determine the proper treatment protocol for each individual patient with giant cell tumour of tendon sheath [24].

Anatomy & Pathophysiology

Giant cell tumors of the tendon sheath (GCTTS) exhibit variable presentation patterns. Separate concomitant lesions may occur on both the volar and dorsal aspects of the same hand [7]. Multiple GCTTS involving three digits of the same hand have been reported following repetitive trauma, such as repeated back-hand blows over more than 20 years [7]. Pigmented villonodular synovitis can involve multiple joints simultaneously, such as the left shoulder glenohumeral joint and ankle joint [18].

Knowledge of anatomy and surgical approaches is critical for optimal repair in hand surgery [20]. Effective surgery aims to restore biomechanical motions to enable optimum use of the digits [25]. The intrinsic muscles have specific structural and functional anatomy, and their dysfunction has defined effects on hand mechanics [28]. Rehabilitation methods are available to address intrinsic muscle dysfunction [28].

Classification

Benign Synovial Neoplasm: Giant cell tumour of tendon sheath is a benign synovial neoplasm [3]. It is a common benign tumour of the hand [1] and a benign lesion of the synovial sheaths in the hand [2]. Reports in the paediatric population are rare, with a case in a 4-year-old boy believed to be the youngest reported [1].

Tenosynovial Giant Cell Tumors: This category includes pigmented villonodular synovitis and giant-cell tumor of the tendon sheath [4]. Both are benign synovial neoplasms with the potential for local recurrence [3]. Recurrence is the primary risk associated with these tumors in the hand [2]. Diffuse disease presents challenges due to high recurrence rates [4].

Other Considerations: Multifocal, recurrent, bilateral giant cell tumor of the tendon sheath and pigmented villonodular synovitis involving both upper and lower extremities is a rare instance [5]. Separate concomitant giant cell tumors occurring on both aspects of the same hand is a rare presentation [7]. Pigmented villonodular synovitis can mimic primary bone neoplasms such as giant-cell tumor due to extensive lytic bone destruction [19]. Diffuse pigmented villonodular synovitis can mimic primary bone neoplasms, potentially leading to unnecessarily radical surgery if the diagnosis is not suspected [19]. Extra-articular invasion of diffuse pigmented villonodular synovitis/tenosynovial giant cell tumor in the knee joints occurs in specific patterns [55]. Lesions in the intra-articular posterior compartments are observed in all diffuse extra-articular pigmented villonodular synovitis/tenosynovial giant cell tumor patients [55].

Clinical Presentation

Giant cell tumour of tendon sheath (GCTTS) is a common benign tumour of the hand [1]. Although rare, it can present in the paediatric population [1]. The clinical course is characterized by slow progression and relatively nonspecific symptoms [30]. While typically solitary, GCTTS can present as multifocal lesions [5], bilateral lesions [5], or involve both upper and lower extremities simultaneously [5]. Intra-hand presentations may include separate concomitant lesions on both the volar and dorsal aspects of the same hand [7], or separate lesions involving three digits of the same hand [7].

Tenosynovial giant cell tumors (formerly GCTTS) in unusual locations can be confused with malignant tumors on positron emission tomography imaging [17]. Pigmented villonodular synovitis (PVNS), a benign synovial neoplasm, shares similar presentation features [3]. PVNS can present as multifocal disease [5], bilateral disease [5], or involve both upper and lower extremities simultaneously [5]. Clinical and radiological findings of PVNS are generally nonspecific [16].

Diffuse PVNS can mimic primary bone neoplasms such as giant-cell tumor [19] and cause extensive lytic bone destruction [19]. Shoulder involvement is extremely rare [16], but PVNS can present with sub-acromial erosion of the shoulder [36]. Consequently, PVNS should be considered in the differential diagnosis of patients presenting with shoulder pain [36].

Investigations

MRI: Magnetic resonance imaging is the investigation of choice for diagnosing tumour-like lesions of the infrapatellar fat pad [32]. It is essential to diagnose localized pigmented villonodular synovitis (PVNS), define its localization, and establish the treatment strategy [35]. Pre-operative evaluation with MRI contributes to the diagnosis of localized PVNS [47]. MRI provides valuable clues for diagnosing tenosynovial giant cell tumors (TGCT), although definitive diagnosis relies on histopathological confirmation [41]. MRI findings and location can aid in the diagnosis of TGCT, but careful assessment is mandatory, especially in unusual locations [17]. Different MRI signal intensities between osseous and extraosseous lesions can make the diagnosis of TGCT difficult [53]. Early diagnosis via MRI is important for prognosis in cases of peroneal neuropathy secondary to PVNS [52].

CT: CT is useful for identifying osteolytic changes in tenosynovial giant cell tumors [53].

Other Considerations: Clinical and radiological findings of PVNS of the shoulder are generally nonspecific and often mimic malignancy [16]. PVNS can mimic metastases on 18F-FDG PET/CT, particularly in patients with a history of malignancy such as rectal mucosal melanoma [49]. TGCT in unusual locations can be detected by positron emission tomography imaging and confused with malignant tumors [17].

Treatment

Non-Operative

Asymptomatic patients with diffuse pigmented villonovular synovitis of the foot and ankle can be successfully managed nonoperatively [37].

Operative

Indications: Complete surgical resection is the treatment of choice for most patients with tenosynovial giant cell tumors [4]. Diffuse disease presents challenges due to high recurrence rates [4]. The pathogenesis and optimum treatment of pigmented villonovular synovitis remain unclear due to the rarity of cases, varying reporting details, and lack of long-term follow-up in most series [6]. More prospective well-designed studies including a large number of cases are necessary to identify tumors prone to recurrence and determine the proper treatment protocol for each individual patient with giant cell tumor of the tendon sheath [24].

Surgical Approach / Technique: Arthroscopic excision is the treatment of choice for localized pigmented villonovular synovitis and is currently thought to be curative [12]. It is the preferred treatment for localized pigmented villonovular synovitis in the anteromedial compartment of the knee due to its effectiveness and minimal morbidity [50]. Open synovectomy is the standard method of management for pigmented villonovular synovitis [51]. The ideal treatment for pigmented villonovular synovitis is complete operative excision [21]. Complete synovectomy with excision of all lesions is considered the treatment of choice for pigmented villonovular synovitis by most authors [23]. Combined arthroscopic and open synovectomy results in a low rate of symptomatic disease recurrence and good to excellent functional outcomes for diffuse pigmented villonovular synovitis of the knee [45]. Arthroscopic synovectomy provides good functional outcomes without evidence of recurrence in patients with pigmented villonovular synovitis of the hip [9]. There is no consensus on the management of pigmented villonovular synovitis of the hip in current literature [10]. For diffuse-type giant cell tumor with bony erosions about the ankle joint, open synovectomy combined with bone grafting is a safe and effective operation for salvage of the ankle joint [39].

Adjuncts: Roentgen therapy is suggested by some for recurrence of pigmented villonovular synovitis [23]. External beam radiation therapy is essential in the management of a wide spectrum of musculoskeletal conditions, both benign and malignant [8].

Complications

Local Recurrence: Giant cell tumour of tendon sheath (GCTTS) is a benign synovial neoplasm with the potential for local recurrence after excision [1, 3]. Recurrence represents the primary risk for giant cell tumors of the synovial sheaths in the hand [2]. While multifocal, recurrent, and bilateral GCTTS and pigmented villonodular synovitis (PVNS) involving both upper and lower extremities can occur in adults [5], diffuse disease presents specific challenges due to high recurrence rates [4]. The natural history of diffuse-type giant-cell tumour (Dt-GCT) in patients treated by arthroscopic synovectomy is characterized by an unfavourable outcome [15]. Consequently, arthroscopic synovectomy for Dt-GCT around the knee may lead to recurrence or residual disease, often necessitating primary open synovectomy [15]. Additionally, PVNS can present as recurrent spontaneous hemarthrosis nine years after a total knee arthroplasty [54].

Recovery

Giant cell tumour of tendon sheath is a common benign tumour of the hand that can be locally recurrent after excision [1]. Recurrence is the primary risk for giant cell tumors of the synovial sheaths in the hand [2]. Pigmented villonoid synovitis and giant-cell tumor of tendon sheath are benign synovial neoplasms with the potential for local recurrence [3]. Complete surgical resection remains the treatment of choice for most patients with tenosynovial giant cell tumors, though diffuse disease presents challenges due to high recurrence rates [4].

Light activity (weeks): Evidence does not specify a week range for light activity or desk work.

Full activity (months): Evidence does not specify a month range for full activity or manual work.

Complete recovery / outcome plateau (months): Patients reported good functional outcomes without evidence of recurrence in a 19 patient cohort with an average follow-up of almost 7 years following arthroscopic synovectomy for pigmented villonodular synovitis of the hip [9]. After arthroscopic synovectomy and partial rotator cuff repair or debridement for pigmented villonodular synovitis of the shoulder associated with massive rotator cuff tear, all patients gained symptomatic and limited functional improvement at an average follow-up of 22 months [56]. The prognosis after excision of localized pigmented villonodular synovitis of the knee is excellent, with no recurrences observed in the series [57].

Rehabilitation protocol: Evidence does not specify PT phasing, immobilisation duration, or weight-bearing progression.

Functional milestones: Patients reported good functional outcomes without evidence of recurrence in a 19 patient cohort with an average follow-up of almost 7 years following arthroscopic synovectomy for pigmented villonodular synovitis of the hip [9]. After arthroscopic synovectomy and partial rotator cuff repair or debridement for pigmented villonodular synovitis of the shoulder associated with massive rotator cuff tear, all patients gained symptomatic and limited functional improvement at an average follow-up of 22 months [56].

Other Considerations: Arthroscopic synovectomy following a timely diagnosis of pigmented villonoid synovitis produces good outcomes in nodular cases, with no evidence of symptomatic or radiographic disease persistence among these patients [11]. Arthroscopic excision is the treatment of choice for localized pigmented villonodular synovitis and is currently thought to be curative [12]. The natural history of diffuse-type giant-cell tumour in patients treated by arthroscopic synovectomy has an unfavourable outcome, and primary open synovectomy should be undertaken to prevent recurrence or residual disease [15].

Key Evidence

  • [L4] Giant cell tumour of tendon sheath is a common benign tumour of the hand that can be locally recurrent after excision, and reports in the paediatric population are rare, with this case believed to be the youngest reported. (10.1177/1753193412455792)
  • [L4] Giant cell tumors of the synovial sheaths in the hand are benign lesions in which recurrence is the primary risk. (10.1016/j.jhsa.2013.08.051)
  • [L4] Pigmented villonoid synovitis and giant-cell tumor of tendon sheath are benign synovial neoplasms with the potential for local recurrence. (10.2106/00004623-198466010-00012)
  • [L5] Complete surgical resection remains the treatment of choice for most patients with tenosynovial giant cell tumors, though diffuse disease presents challenges due to high recurrence rates. (10.5435/jaaos-d-24-01255)
  • [Case_report] This case report describes a rare instance of multifocal, recurrent, bilateral giant cell tumor of the tendon sheath and pigmented villonodular synovitis involving both upper and lower extremities in an adult. (10.1016/j.jhsa.2014.11.010)
  • [L4] The pathogenesis and optimum treatment of pigmented villonodular synovitis remain unclear, with uncertainties persisting due to the rarity of cases, varying reporting details, and lack of long-term follow-up in most series. (10.2106/00004623-198769060-00026)
  • [L5] This case describes the first report of separate concomitant giant cell tumors occurring on both aspects of the same hand, suggesting a potential micro-traumatic origin due to repeated back-hand blows over more than 20 years. (10.1007/s12593-015-0185-3)
  • [L5] External beam radiation therapy is essential in the management of a wide spectrum of musculoskeletal conditions, both benign and malignant. (10.5435/jaaos-d-14-00022)
  • [L4] Patients reported good functional outcomes without evidence of recurrence in a 19 patient cohort with an average follow-up of almost 7 years. (10.1177/2325967119s00413)
  • [L5] There is no consensus on the management of PVNS of the hip in current literature; the article discusses options for surgical intervention based on a review of clinical, biological, etiological, histological and radiographic aspects. (10.1302/2058-5241.1.000021)
  • [L4] Arthroscopic synovectomy following a timely diagnosis of PVNS produces good outcomes in nodular cases, with no evidence of symptomatic or radiographic disease persistence among these patients. (10.1177/2325967118763118)
  • [L4] Arthroscopic excision is the treatment of choice and is currently thought to be curative. (10.1016/j.arthro.2005.12.035)
  • [L3] The natural history of Dt-GCT in patients treated by arthroscopic synovectomy has an unfavourable outcome, and primary open synovectomy should be undertaken to prevent recurrence or residual disease. (10.1302/0301-620x.96b8.33608)
  • [Case_report] PVNS of the shoulder is extremely rare, with clinical and radiological findings generally being nonspecific and often mimicking a malignancy. (10.1007/s001670050158)
  • [L4] Although MRI findings and location might help in the diagnosis of a T-GCT, careful assessment is mandatory, especially in unusual locations. (10.1186/s12891-016-1050-7)
  • [Case_report] Early diagnosis and appropriate intervention are critical to prevent joint destruction and optimize patient outcomes. (10.1186/s12891-025-08936-x)
  • [L5] Diffuse pigmented villonodular synovitis can mimic primary bone neoplasms such as giant-cell tumor due to extensive lytic bone destruction, potentially leading to unnecessarily radical surgery if the diagnosis is not suspected. (10.2106/00004623-197860060-00019)
  • [L5] Every step thereafter can be influenced by him or her, though, and a thorough knowledge of anatomy and surgical approaches allows for the best possible repair under any set of circumstances. (10.1016/j.hcl.2004.11.003)
  • [Case_report] The ideal treatment for pigmented villonodular synovitis is complete operative excision. (10.2106/00004623-199072060-00022)
  • [L4] The authors note that while roentgen therapy is suggested by some for recurrence, complete synovectomy with excision of all lesions is considered the treatment of choice by most authors. (10.2106/00004623-195436050-00009)
  • [L1] More prospective well-designed studies including a large number of cases are necessary to identify tumours prone to recurrence and determine the proper treatment protocol for each individual patient. (10.1007/s11552-011-9341-9)
  • [L5] Ideally, digits need sensation and freedom of motion to enable patients to use them effectively, and effective surgery restores biomechanical motions so patients have optimum use. (10.1016/j.hcl.2013.08.003)
  • [L5] The purpose of this issue is to provide a comprehensive review of the intrinsic muscles, their structural and functional anatomy, the effect of their dysfunction, and the various methods that can be used for rehabilitation. (10.1016/j.hcl.2011.09.007)
  • [L4] TSGCT is a benign entity with relatively nonspecific symptoms and slow progression; treatment is never urgent and indications should be discussed according to symptomatology, progression, location, and diathesis. (10.1016/j.otsr.2016.11.002)
  • [L4] MRI is the investigation of choice for diagnosing these tumour-like lesions. (10.1007/s00167-009-1034-3)
  • [L4] Magnetic resonance imaging is essential to diagnose this pathologic condition and to define accurately its localization and treatment strategy. (10.1007/s00167-011-1747-y)
  • [L4] PVNS may present with sub-acromial erosion of the shoulder and should be considered in the differential diagnosis of patients presenting with shoulder pain. (10.1007/s00167-009-0752-x)
  • [L4] Asymptomatic patients can be successfully managed nonoperatively. (10.1302/0301-620x.95b3.30192)
  • [L4] For Dt-GCT with bony erosions, open synovectomy combined with bone grafting seems to be a safe and effective operation for the salvage of ankle joint. (10.1186/s12891-017-1824-6)
  • [L4] MRI provides valuable clues, but definitive diagnosis relies on histopathological confirmation. (10.1186/s12891-026-09563-w)
  • [L4] Combined synovectomy resulted in a low rate of symptomatic disease recurrence and good to excellent functional outcomes for diffuse PVNS of the knee. (10.1007/s00167-014-3375-9)
  • [L4] Pre-operative evaluation with MRI made an important contribution to the diagnosis of LPNS. (10.1007/s00167-002-0318-7)
  • [Case_report] The case serves as a reminder that not all lesions with high 18F-FDG uptake, especially those near a joint, are metastases and that more extensive resection is unnecessary. (10.1186/s12891-019-3034-x)
  • [L4] Arthroscopic excision is the preferred treatment due to its effectiveness and minimal morbidity. (10.1007/s00167-003-0448-6)
  • [L4] Open synovectomy is the standard method of management. (10.5435/00124635-200606000-00007)
  • [Case_report] Early diagnosis via MRI and EMG is very important for prognosis, and early surgical resection of all pathologic tissues is necessary. (10.1007/s00167-009-0720-5)
  • [L4] CT is useful for osteolytic identification, while different MRI signal intensities between osseous and extraosseous lesions made the diagnosis difficult. (10.1016/j.xrrt.2021.04.015)
  • [L5] The authors hope this report will encourage documentation of similar late occurrences to further understand the etiology of this condition. (10.2106/00004623-199305000-00018)
  • [L4] Extra-articular invasion of diffuse PVNS/TGCT occurred in specific patterns in the knee joint, with lesions in the intra-articular posterior compartments observed in all diffuse extra-articular PVNS/TGCT patients. (10.1007/s00167-018-4942-2)
  • [L4] After arthroscopic synovectomy and partial rotator cuff repair or debridement, all patients gained symptomatic and limited functional improvement at an average follow-up of 22 months. (10.1016/j.arthro.2009.01.007)
  • [L4] The prognosis after excision is excellent, with no recurrences observed in this series. (10.2106/00004623-196749010-00010)

See Also

References

[1] Giant cell tumour of tendon sheath in a 4-year-old boy. Journal of Hand Surgery (European Volume). 2012. DOI: 10.1177/1753193412455792

[2] Giant Cell Tumors of the Tendon Sheaths in the Hand: Review of 96 Patients With an Average Follow-Up of 12 Years. The Journal of Hand Surgery. 2013. DOI: 10.1016/j.jhsa.2013.08.051

[3] Pigmented villonodular synovitis (giant-cell tumor of the tendon sheath and synovial membrane). A review of eighty-one cases.. The Journal of Bone & Joint Surgery. 1984. DOI: 10.2106/00004623-198466010-00012

[4] Tenosynovial Giant Cell Tumor and Pigmented Villonodular Synovitis. Journal of the American Academy of Orthopaedic Surgeons. 2025. DOI: 10.5435/jaaos-d-24-01255

[5] Recurrent Pigmented Villonodular Synovitis and Multifocal Giant Cell Tumor of the Tendon Sheath: Case Report. The Journal of Hand Surgery. 2015. DOI: 10.1016/j.jhsa.2014.11.010

[6] Pigmented villonodular synovitis.. The Journal of Bone & Joint Surgery. 1987. DOI: 10.2106/00004623-198769060-00026

[7] Multiple Giant Cell Tumors of the Tendon Sheath : Separate Volar and Dorsal Lesions Involving Three Digits of the Same Hand Following Repetitive Trauma. Journal of Hand and Microsurgery. 2015. DOI: 10.1007/s12593-015-0185-3

[8] External Beam Radiation Therapy for Orthopaedic Pathology. Journal of the American Academy of Orthopaedic Surgeons. 2015. DOI: 10.5435/jaaos-d-14-00022

[9] Pigmented Villonodular Synovitis of the Hip Managed with Arthroscopic Synovectomy: An Analysis of 19 Cases with up to 10-year Follow-up. Orthopaedic Journal of Sports Medicine. 2019. DOI: 10.1177/2325967119s00413

[10] Pigmented villonodular synovitis of the hip. EFORT Open Reviews. 2016. DOI: 10.1302/2058-5241.1.000021

[11] Arthroscopic Management of Pigmented Villonodular Synovitis of the Hip in Children and Adolescents. Orthopaedic Journal of Sports Medicine. 2018. DOI: 10.1177/2325967118763118

[12] Localized Pigmented Villonodular Synovitis: Arthroscopic Treatment of a Lesion Arising From the Quadriceps Tendon Sheath. Arthroscopy. 2006. DOI: 10.1016/j.arthro.2005.12.035

[15] Functional outcome and quality of life after the surgical treatment for diffuse-type giant-cell tumour around the knee. The Bone & Joint Journal. 2014. DOI: 10.1302/0301-620x.96b8.33608

[16] Pigmented villonodular synovitis of the shoulder: review and case report. Knee Surgery, Sports Traumatology, Arthroscopy. 1999. DOI: 10.1007/s001670050158

[17] Tenosynovial giant cell tumors in unusual locations detected by positron emission tomography imaging confused with malignant tumors: report of two cases. BMC Musculoskeletal Disorders. 2016. DOI: 10.1186/s12891-016-1050-7

[18] Simultaneous involvement of pigmented villonodular synovitis in the left shoulder glenohumeral joint and ankle joint: a rare case report. BMC Musculoskeletal Disorders. 2025. DOI: 10.1186/s12891-025-08936-x

[19] Diffuse pigmented villonodular synovitis of the knee mimicking primary bone neoplasms. A report of two cases.. The Journal of Bone & Joint Surgery. 1978. DOI: 10.2106/00004623-197860060-00019

[20] Flexor Tendons: Anatomy and Surgical Approaches. Hand Clinics. 2005. DOI: 10.1016/j.hcl.2004.11.003

[21] Pigmented villonodular synovitis in a vertebra. A case report.. The Journal of Bone & Joint Surgery. 1990. DOI: 10.2106/00004623-199072060-00022

[23] PIGMENTED VILLONODULAR SYNOVITIS OF THE HIP JOINT. The Journal of Bone & Joint Surgery. 1954. DOI: 10.2106/00004623-195436050-00009

[24] Giant Cell Tumour of Tendon Sheath of the Digits. A Systematic Review. HAND. 2011. DOI: 10.1007/s11552-011-9341-9

[25] Biomechanics of the Hand. Hand Clinics. 2013. DOI: 10.1016/j.hcl.2013.08.003

[28] Preface. Hand Clinics. 2012. DOI: 10.1016/j.hcl.2011.09.007

[30] Localized and diffuse forms of tenosynovial giant cell tumor (formerly giant cell tumor of the tendon sheath and pigmented villonodular synovitis). Orthopaedics & Traumatology: Surgery & Research. 2017. DOI: 10.1016/j.otsr.2016.11.002

[32] Tumour‐like lesions of the infrapatellar fat pad. Knee Surgery, Sports Traumatology, Arthroscopy. 2010. DOI: 10.1007/s00167-009-1034-3

[35] Arthroscopic treatment of localized pigmented villonodular synovitis of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2011. DOI: 10.1007/s00167-011-1747-y

[36] Subacromial bony erosion: a rare presentation of pigmented villonodular synovitis of the shoulder. Knee Surgery, Sports Traumatology, Arthroscopy. 2009. DOI: 10.1007/s00167-009-0752-x

[37] Diffuse pigmented villonodular synovitis (diffuse-type giant cell tumour) of the foot and ankle. The Bone & Joint Journal. 2013. DOI: 10.1302/0301-620x.95b3.30192

[39] Surgical treatment for diffused-type giant cell tumor (pigmented villonodular synovitis) about the ankle joint. BMC Musculoskeletal Disorders. 2017. DOI: 10.1186/s12891-017-1824-6

[41] Two rare intra-articsular knee disorders with overlapping symptoms: separate case reports of tenosynovial giant cell tumour and lipoma arborescens and literature review. BMC Musculoskeletal Disorders. 2026. DOI: 10.1186/s12891-026-09563-w

[45] Combined arthroscopic and open synovectomy for diffuse pigmented villonodular synovitis of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2014. DOI: 10.1007/s00167-014-3375-9

[47] Two contrasting presentations of localised pigmented villonodular synovitis of the knee. Knee Surgery, Sports Traumatology, Arthroscopy. 2002. DOI: 10.1007/s00167-002-0318-7

[49] Pigmented villous nodular synovitis mimicking metastases on 18F-FDG PET/CT in a patient with rectal mucosal melanoma: a case report. BMC Musculoskeletal Disorders. 2020. DOI: 10.1186/s12891-019-3034-x

[50] Localized pigmented villonodular synovitis in the anteromedial compartment of the knee associated with cartilage lesions of the medial femoral condyle: report of a case and review of the literature. Knee Surgery, Sports Traumatology, Arthroscopy. 2004. DOI: 10.1007/s00167-003-0448-6

[51] Pigmented Villonodular Synovitis. Journal of the American Academy of Orthopaedic Surgeons. 2006. DOI: 10.5435/00124635-200606000-00007

[52] An unusual presentation of peroneal neuropathy secondary to pigmented villonodular synovitis: a case report. Knee Surgery, Sports Traumatology, Arthroscopy. 2009. DOI: 10.1007/s00167-009-0720-5

[53] Tenosynovial giant cell tumor in the elbow of a child with the sole symptom of extension disturbance. JSES Reviews, Reports, and Techniques. 2021. DOI: 10.1016/j.xrrt.2021.04.015

[54] Recurrent spontaneous hemarthrosis nine years after a total knee arthroplasty. A presentation with pigmented villonodular synovitis.. The Journal of Bone & Joint Surgery. 1993. DOI: 10.2106/00004623-199305000-00018

[55] Distinct extra-articular invasion patterns of diffuse pigmented villonodular synovitis/tenosynovial giant cell tumor in the knee joints. Knee Surgery, Sports Traumatology, Arthroscopy. 2018. DOI: 10.1007/s00167-018-4942-2

[56] Arthroscopic Treatment for Pigmented Villonodular Synovitis of the Shoulder Associated With Massive Rotator Cuff Tear. Arthroscopy. 2009. DOI: 10.1016/j.arthro.2009.01.007

[57] Localized Pigmented Villonodular Synovitis of the Knee. The Journal of Bone & Joint Surgery. 1967. DOI: 10.2106/00004623-196749010-00010

Creative Commons BY-NC 4.0

CC Creative Commons licence
BY Attribution — you must credit the source
NC NonCommercial — not for commercial use

Attribution-NonCommercial 4.0 International

Creative Commons Corporation ("Creative Commons") is not a law firm and does not provide legal services or legal advice. Distribution of Creative Commons public licenses does not create a lawyer-client or other relationship. Creative Commons makes its licenses and related information available on an "as-is" basis. Creative Commons gives no warranties regarding its licenses, any material licensed under their terms and conditions, or any related information. Creative Commons disclaims all liability for damages resulting from their use to the fullest extent possible.

Using Creative Commons Public Licenses

Creative Commons public licenses provide a standard set of terms and conditions that creators and other rights holders may use to share original works of authorship and other material subject to copyright and certain other rights specified in the public license below. The following considerations are for informational purposes only, are not exhaustive, and do not form part of our licenses.

Considerations for licensors: Our public licenses are intended for use by those authorized to give the public permission to use material in ways otherwise restricted by copyright and certain other rights. Our licenses are irrevocable. Licensors should read and understand the terms and conditions of the license they choose before applying it. Licensors should also secure all rights necessary before applying our licenses so that the public can reuse the material as expected. Licensors should clearly mark any material not subject to the license. This includes other CC- licensed material, or material used under an exception or limitation to copyright. More considerations for licensors: wiki.creativecommons.org/Considerations_for_licensors

Considerations for the public: By using one of our public licenses, a licensor grants the public permission to use the licensed material under specified terms and conditions. If the licensor's permission is not necessary for any reason--for example, because of any applicable exception or limitation to copyright--then that use is not regulated by the license. Our licenses grant only permissions under copyright and certain other rights that a licensor has authority to grant. Use of the licensed material may still be restricted for other reasons, including because others have copyright or other rights in the material. A licensor may make special requests, such as asking that all changes be marked or described. Although not required by our licenses, you are encouraged to respect those requests where reasonable. More considerations for the public: wiki.creativecommons.org/Considerations_for_licensees

Creative Commons Attribution-NonCommercial 4.0 International Public License

By exercising the Licensed Rights (defined below), You accept and agree to be bound by the terms and conditions of this Creative Commons Attribution-NonCommercial 4.0 International Public License ("Public License"). To the extent this Public License may be interpreted as a contract, You are granted the Licensed Rights in consideration of Your acceptance of these terms and conditions, and the Licensor grants You such rights in consideration of benefits the Licensor receives from making the Licensed Material available under these terms and conditions.

Section 1 -- Definitions.

a. Adapted Material means material subject to Copyright and Similar Rights that is derived from or based upon the Licensed Material and in which the Licensed Material is translated, altered, arranged, transformed, or otherwise modified in a manner requiring permission under the Copyright and Similar Rights held by the Licensor. For purposes of this Public License, where the Licensed Material is a musical work, performance, or sound recording, Adapted Material is always produced where the Licensed Material is synched in timed relation with a moving image.

b. Adapter's License means the license You apply to Your Copyright and Similar Rights in Your contributions to Adapted Material in accordance with the terms and conditions of this Public License.

c. Copyright and Similar Rights means copyright and/or similar rights closely related to copyright including, without limitation, performance, broadcast, sound recording, and Sui Generis Database Rights, without regard to how the rights are labeled or categorized. For purposes of this Public License, the rights specified in Section 2(b)(1)-(2) are not Copyright and Similar Rights.

d. Effective Technological Measures means those measures that, in the absence of proper authority, may not be circumvented under laws fulfilling obligations under Article 11 of the WIPO Copyright Treaty adopted on December 20, 1996, and/or similar international agreements.

e. Exceptions and Limitations means fair use, fair dealing, and/or any other exception or limitation to Copyright and Similar Rights that applies to Your use of the Licensed Material.

f. Licensed Material means the artistic or literary work, database, or other material to which the Licensor applied this Public License.

g. Licensed Rights means the rights granted to You subject to the terms and conditions of this Public License, which are limited to all Copyright and Similar Rights that apply to Your use of the Licensed Material and that the Licensor has authority to license.

h. Licensor means the individual(s) or entity(ies) granting rights under this Public License.

i. NonCommercial means not primarily intended for or directed towards commercial advantage or monetary compensation. For purposes of this Public License, the exchange of the Licensed Material for other material subject to Copyright and Similar Rights by digital file-sharing or similar means is NonCommercial provided there is no payment of monetary compensation in connection with the exchange.

j. Share means to provide material to the public by any means or process that requires permission under the Licensed Rights, such as reproduction, public display, public performance, distribution, dissemination, communication, or importation, and to make material available to the public including in ways that members of the public may access the material from a place and at a time individually chosen by them.

k. Sui Generis Database Rights means rights other than copyright resulting from Directive 96/9/EC of the European Parliament and of the Council of 11 March 1996 on the legal protection of databases, as amended and/or succeeded, as well as other essentially equivalent rights anywhere in the world.

l. You means the individual or entity exercising the Licensed Rights under this Public License. Your has a corresponding meaning.

Section 2 -- Scope.

a. License grant.

1. Subject to the terms and conditions of this Public License, the Licensor hereby grants You a worldwide, royalty-free, non-sublicensable, non-exclusive, irrevocable license to exercise the Licensed Rights in the Licensed Material to:

a. reproduce and Share the Licensed Material, in whole or in part, for NonCommercial purposes only; and

b. produce, reproduce, and Share Adapted Material for NonCommercial purposes only.

2. Exceptions and Limitations. For the avoidance of doubt, where Exceptions and Limitations apply to Your use, this Public License does not apply, and You do not need to comply with its terms and conditions.

3. Term. The term of this Public License is specified in Section 6(a).

4. Media and formats; technical modifications allowed. The Licensor authorizes You to exercise the Licensed Rights in all media and formats whether now known or hereafter created, and to make technical modifications necessary to do so. The Licensor waives and/or agrees not to assert any right or authority to forbid You from making technical modifications necessary to exercise the Licensed Rights, including technical modifications necessary to circumvent Effective Technological Measures. For purposes of this Public License, simply making modifications authorized by this Section 2(a) (4) never produces Adapted Material.

5. Downstream recipients.

a. Offer from the Licensor -- Licensed Material. Every recipient of the Licensed Material automatically receives an offer from the Licensor to exercise the Licensed Rights under the terms and conditions of this Public License.

b. No downstream restrictions. You may not offer or impose any additional or different terms or conditions on, or apply any Effective Technological Measures to, the Licensed Material if doing so restricts exercise of the Licensed Rights by any recipient of the Licensed Material.

6. No endorsement. Nothing in this Public License constitutes or may be construed as permission to assert or imply that You are, or that Your use of the Licensed Material is, connected with, or sponsored, endorsed, or granted official status by, the Licensor or others designated to receive attribution as provided in Section 3(a)(1)(A)(i).

b. Other rights.

1. Moral rights, such as the right of integrity, are not licensed under this Public License, nor are publicity, privacy, and/or other similar personality rights; however, to the extent possible, the Licensor waives and/or agrees not to assert any such rights held by the Licensor to the limited extent necessary to allow You to exercise the Licensed Rights, but not otherwise.

2. Patent and trademark rights are not licensed under this Public License.

3. To the extent possible, the Licensor waives any right to collect royalties from You for the exercise of the Licensed Rights, whether directly or through a collecting society under any voluntary or waivable statutory or compulsory licensing scheme. In all other cases the Licensor expressly reserves any right to collect such royalties, including when the Licensed Material is used other than for NonCommercial purposes.

Section 3 -- License Conditions.

Your exercise of the Licensed Rights is expressly made subject to the following conditions.

a. Attribution.

1. If You Share the Licensed Material (including in modified form), You must:

a. retain the following if it is supplied by the Licensor with the Licensed Material:

i. identification of the creator(s) of the Licensed Material and any others designated to receive attribution, in any reasonable manner requested by the Licensor (including by pseudonym if designated);

ii. a copyright notice;

iii. a notice that refers to this Public License;

iv. a notice that refers to the disclaimer of warranties;

v. a URI or hyperlink to the Licensed Material to the extent reasonably practicable;

b. indicate if You modified the Licensed Material and retain an indication of any previous modifications; and

c. indicate the Licensed Material is licensed under this Public License, and include the text of, or the URI or hyperlink to, this Public License.

2. You may satisfy the conditions in Section 3(a)(1) in any reasonable manner based on the medium, means, and context in which You Share the Licensed Material. For example, it may be reasonable to satisfy the conditions by providing a URI or hyperlink to a resource that includes the required information.

3. If requested by the Licensor, You must remove any of the information required by Section 3(a)(1)(A) to the extent reasonably practicable.

4. If You Share Adapted Material You produce, the Adapter's License You apply must not prevent recipients of the Adapted Material from complying with this Public License.

Section 4 -- Sui Generis Database Rights.

Where the Licensed Rights include Sui Generis Database Rights that apply to Your use of the Licensed Material:

a. for the avoidance of doubt, Section 2(a)(1) grants You the right to extract, reuse, reproduce, and Share all or a substantial portion of the contents of the database for NonCommercial purposes only;

b. if You include all or a substantial portion of the database contents in a database in which You have Sui Generis Database Rights, then the database in which You have Sui Generis Database Rights (but not its individual contents) is Adapted Material; and

c. You must comply with the conditions in Section 3(a) if You Share all or a substantial portion of the contents of the database.

For the avoidance of doubt, this Section 4 supplements and does not replace Your obligations under this Public License where the Licensed Rights include other Copyright and Similar Rights.

Section 5 -- Disclaimer of Warranties and Limitation of Liability.

a. UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU.

b. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU.

c. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.

Section 6 -- Term and Termination.

a. This Public License applies for the term of the Copyright and Similar Rights licensed here. However, if You fail to comply with this Public License, then Your rights under this Public License terminate automatically.

b. Where Your right to use the Licensed Material has terminated under Section 6(a), it reinstates:

1. automatically as of the date the violation is cured, provided it is cured within 30 days of Your discovery of the violation; or

2. upon express reinstatement by the Licensor.

For the avoidance of doubt, this Section 6(b) does not affect any right the Licensor may have to seek remedies for Your violations of this Public License.

c. For the avoidance of doubt, the Licensor may also offer the Licensed Material under separate terms or conditions or stop distributing the Licensed Material at any time; however, doing so will not terminate this Public License.

d. Sections 1, 5, 6, 7, and 8 survive termination of this Public License.

Section 7 -- Other Terms and Conditions.

a. The Licensor shall not be bound by any additional or different terms or conditions communicated by You unless expressly agreed.

b. Any arrangements, understandings, or agreements regarding the Licensed Material not stated herein are separate from and independent of the terms and conditions of this Public License.

Section 8 -- Interpretation.

a. For the avoidance of doubt, this Public License does not, and shall not be interpreted to, reduce, limit, restrict, or impose conditions on any use of the Licensed Material that could lawfully be made without permission under this Public License.

b. To the extent possible, if any provision of this Public License is deemed unenforceable, it shall be automatically reformed to the minimum extent necessary to make it enforceable. If the provision cannot be reformed, it shall be severed from this Public License without affecting the enforceability of the remaining terms and conditions.

c. No term or condition of this Public License will be waived and no failure to comply consented to unless expressly agreed to by the Licensor.

d. Nothing in this Public License constitutes or may be interpreted as a limitation upon, or waiver of, any privileges and immunities that apply to the Licensor or You, including from the legal processes of any jurisdiction or authority.

Creative Commons is not a party to its public licenses. Notwithstanding, Creative Commons may elect to apply one of its public licenses to material it publishes and in those instances will be considered the “Licensor.” The text of the Creative Commons public licenses is dedicated to the public domain under the CC0 Public Domain Dedication. Except for the limited purpose of indicating that material is shared under a Creative Commons public license or as otherwise permitted by the Creative Commons policies published at creativecommons.org/policies, Creative Commons does not authorize the use of the trademark "Creative Commons" or any other trademark or logo of Creative Commons without its prior written consent including, without limitation, in connection with any unauthorized modifications to any of its public licenses or any other arrangements, understandings, or agreements concerning use of licensed material. For the avoidance of doubt, this paragraph does not form part of the public licenses.

Creative Commons may be contacted at creativecommons.org.