Imaging features of temporomandibular joint synovial chondromatosis with associated osseous degenerative changes

Synovial chondromatosis (SC) of the temporomandibular joint (TMJ) is a rare benign disease associated with the formation of multiple cartilaginous nodules in the synovial tissue of the TMJ. This can result in pain, swelling, clicking, limited mouth opening, and osseous degenerative joint changes. A retrospective cross-sectional study was performed to summarize the clinical features, radiographic findings, and surgical and histopathological findings of TMJ SC patients who underwent open surgery over a 24-year period. A radiographic scoring system was used to evaluate osseous changes and correlate condyle and joint fossa degeneration. The study included 38 patients and focused on 38 joints. All 38 of these joints showed degenerative changes in the condyle, while 37 showed osseous degenerative changes in the articular fossa. The degree of condylar degenerative changes was related to the duration of the chief complaints (r = 0.342, P = 0.036) and the histopathological stage of the TMJ SC (r = 0.440, P = 0.006), while the degree of joint fossa degenerative changes was associated with the radiographic extent of the SC (r = 0.504, P = 0.001), type of calcification (r = 0.365, P = 0.024), and the histopathological stage (r = 0.458, P = 0.004).

A case of synovial chondromatosis of the knee with 87 free bodies and review of literature

BACKGROUND

Synovial chondromatosis is a non-malignant synovial disorder characterized by the presence of cartilage formation within the synovial membrane, leading to the emergence of multiple cartilaginous nodules that may be either attached or unattached. The presence of this anatomical feature is frequently observed in articulations such as the knee, hip, elbow, and ankle.

CASE REPORT

In this study, we present a case of synovial chondromatosis in the knee joint of a healthy male in his early 60s. Notably, the patient exhibited the simultaneous presence of 87 large loose bodies. The occurrence of a substantial quantity of unattached entities of notable dimensions within the joint is highly uncommon.

CONCLUSIONS

The patient had several synovial chondromas, a rare disease. Synovial chondromatosis is a benign disorder; however, growing synovium can cause pyogenic cartilage nodules. Most loose bodies in joints can abrade and degenerate articular cartilage, causing long-term discomfort. Thus, an early-stage procedure to remove loose bodies and carefully excise synovial tissue is necessary to treat this condition.

Retrospective study of synovial chondromatosis of the temporomandibular joint: clinical and histopathologic analysis and the early-stage imaging features

OBJECTIVE

Herein, we aimed to study the clinical, radiographical, and histopathologic features of synovial chondromatosis in the temporomandibular joint (SC in TMJ) and provide references for early diagnosis and treatment prognosis.

STUDY DESIGN

The medical records and imaging examinations of patients with SC in TMJ, diagnosed using postoperative histopathologic examination, were reviewed and analyzed. Among them, 18 cases who lacked calcified loose bodies on spiral computed tomography or cone beam computed tomography (SCT/CBCT) were selected for further study. Descriptive statistical methods were used to analyze the clinical characteristics of patients.

RESULTS

The study included 100 patients with SC in TMJ, who were predominantly female (male to female: 1:3), and were aged from 21 to 77 years (median, 47). Radiopaque calcified lesions on SCT/CBCT were missing in 18 cases, but cartilaginous nodules were observed during surgery. The cases lacking calcification had a relatively shorter disease course, suggesting they were in the early stages of SC.

CONCLUSION

In the early stage of SC, although calcified loose bodies cannot be detected on SCT/CBCT, attention should be paid to the widening of the posterior superior joint space and sclerosis or slight erosion of the joint fossa. Magnetic resonance imaging would be helpful to detect the early-stage SC in TMJ.

[Synovial chondromatosis]

Synovial chondromatosis is a rare pathology that involves most frequently the weight-bearing joints. It is due to the development of cartilaginous bodies from the synovial membrane that could migrate threw the joint. Primary and secondary forms exist. Clinical examination will be marked by swellings and loss of mobility. Cross-sectional imaging has the preference. The treatment of choice is the removal of cartilaginous loose bodies with or without a synovectomy.

Synovial chondromatosis: a case series and review of the literature

This case series reviews 2 patients worked up and treated for unilateral synovial chondromatosis of the temporomandibular joint (TMJ). The first was a 58-year-old female evaluated and treated for synovial chondromatosis of the left TMJ using an arthrotomy of the joint to remove the cartilaginous and osteocartilaginous nodules. The second is a 63-year-old male who was evaluated and treated for synovial chondromatosis of the right TMJ with the removal of extracapsular masses and an arthrotomy with intra-joint removal of nodules. Six-year radiographic follow-up demonstrated no recurrence of the pathology in his case. The cases are reviewed in this article, along with a current review of the literature.

Intermediate Outcomes of Shoulder Synovial Chondromatosis in an Adolescent Boy: A Case Report

CASE

Synovial chondromatosis is a rare condition affecting synovial joints. It occurs uncommonly in the shoulder and is rare in the pediatric population. We present a case of a 13-year-old male patient with shoulder pain who was diagnosed with synovial chondromatosis and a posterior labral tear. He was treated with arthroscopic loose body removal, synovectomy, and posterior labral repair and recovered well from the surgery. Four years after the surgery, he developed pain in the same shoulder, but the cause of the pain was not investigated per the patient's decision.

CONCLUSION

Synovial chondromatosis should be considered in pediatric patients presenting with shoulder pain and loss of function with potential for recurrence.

Arthroscopic management of synovial chondromatosis with skull base perforation: A case report and literature review

OBJECTIVE

Synovial chondromatosis (SC) of the temporomandibular joint (TMJ) is a synovial membrane disease characterized by the formation of cartilaginous nodules (CN), that may erode the skull base. Historically, cases with skull base involvement have been treated with open surgery. We report a case of TMJ SC with skull base perforation treated and repaired via minimally invasive TMJ arthroscopy and describe the advanced endoscopic operative maneuvers performed.

CASE REPORT

A 34-year-old male presented with a 4-year history of malocclusion and right TMJ arthralgia. Clinical examination demonstrated malocclusion and direct pressure loading pain. Advanced imaging revealed glenoid fossa erosion and numerous homogenous hypointense lesions within an effusion. The initial surgical plan included diagnostic TMJ arthroscopy followed by conversion to open arthroplasty. Endoscopic operative maneuvers allowed for the accomplishment of the surgical goals, completely arthroscopically. Histopathology confirmed SC, and the patient remains on observation, with relief of symptoms.

CONCLUSION

Advanced arthroscopy is a viable treatment option for select cases of TMJ SC with skull base involvement that allowed for access to the joint space, retrieval of biopsy specimens and CN, and repair of the skull defect.

Primary Distal Interphalangeal Joint Tenosynovial Chondromatosis of the Small Finger: A Case Report With Literature Review

Primary synovial chondromatosis is a rare, benign proliferative disease of the joint synovium, tenosynovium, or bursal lining, in which cartilage metaplasia leads to the development of multiple intra-articular and periarticular loose osteocartilaginous bodies. This disease usually involves larger joints (knee, hip, elbow, and shoulder), but it has also rarely been reported in the hand. Patients with this disease complain of pain, swelling, nodules, and decreased range of motion of the affected joint. Due to its nonspecific symptoms and low prevalence, this disease often goes misdiagnosed, leading to delays in patient treatment. In the literature to date, there are only a few reports of primary synovial chondromatosis. In this case report, we present a patient with a rare case of primary synovial chondromatosis localized to right small finger distal interphalangeal joint.

Synovial chondromatosis of the flexor hallucis longus tendon sheath

This case report discusses a rare case of secondary tenosynovial chondromatosis of the flexor hallucis longus (FHL). Synovial chrondomatosis is a rare, benign proliferative cartilaginous lesion arising from the synovial tissue or bursal lining of or near joints. When it is extra-articular, it is considered tenosynovial chondromatosis. The diagnosis is often delayed given the rarity of presentation and non-specific symptoms. The case was highly unusual in that hindfoot pain was caused by several centimetre-sized osteochondral bodies within the FHL tendon sheath. Anterior cheilectomy was performed. The patient returned to full activity following surgery without recurrence of the disease. The condition can be successfully treated operatively.

Temporomandibular joint synovial chondromatosis: An analysis of 7 cases and literature review

OBJECTIVE

To investigate the diagnosis and treatment procedure of synovial chondromatosis (SC) of the temporomandibular joint (TMJ).

METHODS

Clinical features, imaging features, surgical methods, and prognosis of 7 patients with SC of the TMJ were analyzed. We also reviewed and analyzed surgery-relevant literature included in the Pubmed database in the past decade using the search terms "synovial chondromatosis" and "temporomandibular joint", and found 181 cases.

RESULTS

There was no specific difference in the symptoms of SC in the TMJ in different Milgram's stages in our cases and the cases mentioned in the literature. The main symptoms of SC in the TMJ were pain (100%, 7/7; 64.64%, 117/181), limited mouth opening (57.14%, 4/7; 53.59%, 97/181), swelling (14.29%, 1/7; 28.18%, 51/181), crepitus (28.57%, 2/7; 19.34%, 35/181), and clicking (14.29%, 1/7; 9.94%, 18/181) in our cases and cases from literature separately. The imaging features of SC were occupying lesions (including loose bodies or masses) (71.42%, 5/7; 37.57%, 68/181), bone change in condyle or glenoid fossa (1/7, 14.29%; 34.81%, 63/181), effusion (42.86%, 3/7; 20.99%, 38/181), joint space changes (42.86%, 3/7; 11.05%, 20/181) in our cases and cases from literature separately. The surgical procedures seem to depend mainly on the involved structures and the extension of the lesion rather than the Milgram's stage.

CONCLUSIONS

The clinical features of SC in the TMJ are nonspecific and easy to be misdiagnosed. MRI is helpful in the diagnosis of SC in the TMJ. The surgical procedures mainly depend on the involved structures and the extension of the lesion.

Surgical Hip Dislocation for a Diagnostic Dilemma: Differentiating Synovial Chondromatosis and Pigmented Villonodular Synovitis

Pigmented villonodular synovitis (PVNS) and synovial chondromatosis (SC) of the hip are rare synovial diseases that can induce joint destruction without early diagnosis and treatment. The extent of surgical excision is critical given the high rates of recurrence. In the presented case, a 19-year-old female was referred to our institution with progressive left hip pain and radiologic evidence of an intra-articular mass that was consistent with PVNS versus SC. Her medical history was notable for a prior excision of a fibrous lesion at an outside hospital at age 13 with persistent pain. The patient underwent a surgical hip dislocation approach to obtain near-complete visualization of the femoroacetabular joint, ensuring complete evaluation and excision. The tumor was intraoperatively diagnosed as SC and excised accordingly, during an uneventful operation. Pathology confirmed the diagnosis. The essential diagnostic and surgical steps for the management of this pelvic tumor diagnostic dilemma are described. Level of Evidence: V.

Two Cases of Temporomandibular Synovial Chondromatosis Associated with Gli1 Gene Mutation

Synovial chondromatosis (SC) is a rare benign disease involving multifocal generation of ectopic cartilage in the synovial tissue. Herein, we report two cases of SC in the temporomandibular joint: a 38-year-old woman (patient 1) and 39-year-old woman (patient 2). Both patients had trismus, jaw joint noises, and jaw-opening pain in the temporomandibular joint. Cone-beam computed tomography (CT) and magnetic resonance imaging (MRI) in patient 1 showed multiple calcified loose bodies around the right mandibular condyle. In addition, CT and MRI in patient 2 showed multiple calcified loose bodies around the left mandibular condyle and temporal bone perforation. Following establishing a diagnosis of SC, both patients underwent tumor resection via open surgery. In immunohistochemical examinations of the resected tissues, tumor cells showed intense nuclear staining with labeled anti-Gli1 antibody. Gene sequencing revealed that both patients had a homozygous mutation in the Gli1 gene (rs2228226 G>C). In conclusion, we suggest that the Gli1 gene (rs2228226 G>C) may be involved in the etiology of SC.

Giant synovial chondromatosis of hip

Synovial chondromatosis is a rare, benign condition occurring due to metaplasia of synovium. A 65-year-old woman presented with pain in her right hip for 6 years. On examination, a swelling was palpable at the base of scarpa's triangle and her right hip movements were restricted. Imaging modalities showed ossified nodules in the antero-inferior aspect of the hip joint, joint effusion and arthritic changes. We diagnosed the patient to have synovial chondromatosis with secondary arthritis of the hip joint. We performed a total hip arthroplasty with simultaneous synovectomy and extraction of the osteochondral loose bodies, 5 of which were about 2×2 cm in size. We found that excessive acetabular reaming was required due to craters, the osteochondral masses formed on the acetabular surface. Histopathological analysis confirmed the diagnosis. The patient had an excellent functional outcome and no recurrence 5 years following the surgery.

Synovial chondromatosis of the ankle joint: 2 cases treated by open arthrotomy and synovectomy

Synovial chondromatosis is a rare condition consisting of metaplasia of the synovial tissue that usually presents in large joints such as the knee and hip. The reported occurrence of synovial chondromatosis in the foot and ankle joints is rare in the literature. In this case report, the successful surgical management of two patients presenting with this condition using open ankle arthrotomy & synovectomy is described. These two cases are presented to provide added depth to the current literature, as well as presenting a review of published literature to further guide clinicians in the management of this rare condition. LEVEL OF EVIDENCE: 4 (case study).

Secondary synovial chondromatosis of the subacromial subdeltoid bursa with coexisting glenohumeral osteoarthritis: Case report

RATIONALE

Synovial chondromatosis of the shoulder joint is uncommon; this condition usually affects the knee joint and the hip joint. Lesions of multiple chondral nodules form in the synovium and are usually found within the joint capsule. Treatment of synovial chondromatosis consists of loose body removal and synovectomy. In synovial chondromatosis of the shoulder, arthroscopic loose body removal and synovectomy have been reported with good outcomes. Arthroplasty can be a treatment option when osteoarthritis co-occurs at the affected joint. Since incidence of glenohumeral joint osteoarthritis is low compared to osteoarthritis of the knee or hip joints, reports of shoulder synovial chondromatosis treated with arthroplasty are scarce.

PATIENT CONCERNS

A 79-year-old woman presented with right shoulder pain with loss of motion for several years without a history of trauma.

DIAGNOSES

Degenerative changes in the humeral head and glenoid were noted and multiple loose bodies were found in the subdeltoid bursa, and the subacromial bursa. The pathology of loose bodies showed degenerated cartilage tissue and some bony components. Characteristic concentric rings of calcification were observed, indicative of secondary synovial chondromatosis. The diagnosis was secondary synovial chondromatosis of the subacromial subdeltoid bursa with coexisting glenohumeral osteoarthritis.

INTERVENTIONS

The patient was treated with loose body removal, extensive synovectomy, bursectomy and reverse total shoulder arthroplasty.

OUTCOMES

Visual analog scale for shoulder pain, range of motion of shoulder joint had improved demonstrating a good short-term outcome and there was no radiographic evidence of disease recurrence.

LESSONS

In synovial chondromatosis of the shoulder, loose bodies may form in the bursa. In combination with degenerative osteoarthritis of the glenohumeral joint, arthroplasty is a viable option.

Chondrosarcoma Arising in Synovial Chondromatosis of the Hip: A Case Report

CASE

Synovial chondromatosis (SC) is a rare condition involving the proliferation of cartilage within the synovial membrane secondary to subsynovial connective tissue metaplasia. Malignant transformation to chondrosarcoma is rare. We cite a case of SC of the hip refractory to arthroscopic debridement, found to have secondary chondrosarcoma on aborted total hip arthroplasty, in which curative treatment was ultimately obtained with external hemipelvectomy.

CONCLUSION

SC has the potential to undergo malignant transformation to chondrosarcoma. The consequences of not recognizing such transformation can significantly impact patient outcomes and limit options for local control surgery and limb salvage.

Recurrent Synovial Chondromatosis of the Finger

Synovial chondromatosis of the finger is a rare metaplasia affecting either the finger joint or the tendon sheath. It is a benign extraosseus cartilage tumor that often occurs in numbers and is not solitary in nature. This accumulation of masses within the finger can lead the patient to seek medical care. Symptoms are often painful and functionally disabling. Although rare, synovial chondromatosis must be considered in the differential diagnosis for patients with multiple lesions or masses within the hand and finger. Patient workup involves advanced imaging, including magnetic resonance imaging, ultrasonography, and computerized tomography. However, the results of these studies may be inconclusive. Conservative management can be discussed with the patient but has proven to be ineffective. Surgical excision is the recommended first-line treatment. Whether the surgery is arthroscopic or open, with or without synovectomy, is at the surgeon's discretion. Mass recurrence after surgery is an unfortunate complication, and subsequent treatment strategies are undefined. Recurrence may not occur at the same anatomical site. This condition can be intra-articular (within the figure joint) or extra-articular (within the tendon sheath or bursa). Revision surgery in the form of open excision with synovectomy is the mainstay of treatment. There have been only a few case reports of synovial chondromatosis involving the finger. This case series and up-to-date review of the literature presents a discussion of current surgical care. [Orthopedics. 2021;44(3):e454-e457.].

[A case report of extensive intracapsular synovial chondromatosis of the temporomandibular joint]

The article reports a patient with an unusually large synovial chondromatosis of the temporomandibular joint. In this clinical case, the extremely rare sizes of chondral bodies are given, because of which it was required to expand the standard access to the TMJ with the isolation of the trunk and branches of the facial nerve.

A rare case of giant synovial osteochondromatosis of the thigh: A case report

RATIONALE

Giant synovial osteochondromatosis of the thigh is a highly unusual disease without standard diagnosis and curative managements so far. Our focus is to report a very rare case of giant synovial osteochondromatosis successfully operated by surgical treatment. The management of these unique cases has certain educational significance in clinical practice.

PATIENT CONCERNS

A 63-year-old previously healthy man presented to our institution with a 4-year history of continuous progressive hip pain and local numbness of right side in January 2018. One month ago, the patient felt that the above symptoms were aggravated, and the right hip and proximal thigh were significantly swollen.

DIAGNOSIS

Computed tomography and magnetic resonance imaging of the hip revealed the irregular mass in his right thigh. Post-operative pathology confirmed the diagnosis of synovial osteochondromatosis of the thigh.

INTERVENTIONS

Considering the large volume of the mass and possibility of malignancy, the patient underwent surgical exploration and complete tumor resection.

OUTCOMES

The patient's neurological deficits and symptoms improved significantly after the surgery, and the postoperative period was uneventful at the 1-year follow-up visit. There were no complications associated with the operation during the follow-up period.

LESSONS

Taken together, the lesion's clinical features, imaging results, and pathological characteristics are unique. Synovial osteochondromatosis of the thigh, although rare, should be part of the differential diagnosis when the patient presents with local pain, numbness, swelling or other symptoms. We recommend surgical treatment for the occupying lesion when the tumor has caused symptoms or neurological deficits.

Application of a real-time 3-dimensional navigation system for treatment of synovial chondromatosis of the temporomandibular joint: A case report

RATIONALE

Real-time three-dimensional navigation systems can provide useful information for operators during surgery. The authors report a case of synovial chondromatosis of the temporomandibular joint treated by open surgery under the guidance of a real-time 3-dimensional navigation system with a 3-point rigid cranial fixation device.

PATIENT CONCERNS

A 73-year-old woman presented with swelling in the left preauricular region and left temporomandibular joint pain.

DIAGNOSES

The patient was diagnosed with synovial chondromatosis of the temporomandibular joint by imaging examinations.

INTERVENTIONS

The patient was treated by open surgery under the guidance of a real-time 3-dimensional navigation system with a 3-point rigid cranial fixation device.

OUTCOMES

The patient was diagnosed with synovial chondromatosis by histopathological examination. There were no complications. The real-time 3-dimensional navigation system with a 3-point rigid cranial fixation device provided an accurate and useful navigation image and clear surgical field during the surgical procedure. Thirty months have passed since the operation without clinical findings associated with recurrence.

LESSONS

The guidance provided by a real-time 3-dimensional navigation system with a 3-point rigid cranial fixation device is useful in open surgery for the treatment of synovial chondromatosis of the temporomandibular joint.

Carpal tunnel syndrome caused by synovial osteochondromatosis of the finger flexor tendon: A case report

RATIONALE

Carpal tunnel syndrome (CTS) is the most common peripheral nerve neuropathy resulting from compression of the median nerve as it traverses the carpal tunnel. The pathophysiology of this condition is multifactorial, and majority of cases of CTS are idiopathic. We report cases of CTS caused by synovial osteochondromatosis (SOC), which has rarely been reported.

PATIENT CONCERNS

A 45-year-old female was admitted to the clinic due to right hand tingling sensation for 4 months. On physical examination, the patient's symptoms and signs corresponded to the median nerve entrapment at wrist. However, there is mild swelling and tenderness around the second metacarpal bone. Pain was aggravated during wrist and finger flexion.

DIAGNOSES

An electrodiagnostic study revealed CTS. She was advised to begin splinting the hand using a wrist brace and to undergo physiotherapy. After 2 weeks, the tingling sensation decreased slightly. However mild swelling and tenderness around the second metacarpal bone did not improve. Ultrasonography showed multiple echogenic foci. Magnetic resonance imaging (MRI) revealed a nodule at the proximal metacarpal level with synovial thickening, enhancement, and a calcified shadow close to the flexor tendon. After confirming the presence of an osseous nodule with synovial thickening, the patient underwent surgery INTERVENTIONS:: Carpal tunnel release and mass excision with synovectomy of the adjacent structures were performed. Histologically, the lesion was compatible with a diagnosis of SOC.

OUTCOME

The symptoms have improved.

LESSONS

CTS due to SOC on finger flexor tendon is rare but should be considered for possible etiology. Appropriate clinical examination, plain radiography, ultrasonography, and MRI will help physicians to diagnose this condition. In this paper, we report the successful diagnosis and treatment of CTS caused by SOC within the finger flexor tendon.

Synovial chondromatosis of the hip joint in childhood: A case report and literature review

RATIONALE

Pain in the hip joint is a common symptom in children. The common diseases leading to pain in the hip joint in children include transient synovitis of the hip, septic arthritis of the hip, and Legg-Calve-Perthes disease.

PATIENT CONCERNS

A 7-year-old boy was admitted due to pain in the right hip joint and limping for more than 1 month.

DIAGNOSIS

Synovial chondromatosis.

INTERVENTIONS

The patient underwent a hip open surgery, all the loose bodies in articular capsule were removed.

OUTCOMES

At the 6-month follow-up, pain and limping disappeared, and the range of activity of the hip joint was restored to a normal level.

CONCLUSIONS

Synovial chondromatosis is an uncommon disease which can cause pain of hip joint in children.

LESSONS

When the pediatric orthopedic surgeon treats the children suffered with hip pain the surgeon should be aware of this rare disease.

Arthroscopic management of elbow synovial chondromatosis

OBJECTIVE

We aimed to identify factors that affect pain, complications, and function following elbow arthroscopy for elbow synovial chondromatosis.

METHODS

We retrospectively reviewed the cases of all patients with elbow synovial chondromatosis treated by arthroscopic synovectomy and loose body removal between January 2000 and January 2016 at our institution. Eleven patients were enrolled (8 male; mean age, 41.7 years). The mean duration of symptoms was 13.7 months, and all patients had a decreased range of motion (ROM) in the affected elbow. By Milgram criteria, there was 1 phase II case, and 10 cases were phase III.

RESULTS

All patients were followed postoperatively (mean follow-up, 65 months). The preoperatively restricted ROM of 100° flexion (range, 78°-120°) and extension of 30° (range, 15°-40°) were improved to 130° flexion (range, 120°-140°) and -5° hyperextension (range, -10°-0°). Pain, recorded as the pain subscore of the American Shoulder and Elbow Surgeons questionnaire for elbows, was significantly improved from 32 points (range, 20-50) preoperatively to 85 (range, 70-100) postoperatively (on a scale ranging from 0 [worst pain] to 100 [pain-free]). Recurrence occurred in 2 patients (18.2%) who then received arthroscopic synovectomy and loose body removal again. There were no fractures or neurovascular complications, and no patient developed an infection.

CONCLUSION

Arthroscopic management of synovial chondromatosis of the elbow was an effective and safe therapeutic method. After the intervention, immediate and durable improvement of elbow function can be expected.

Arthroscopic Management and Treatment of Synovial Chondromatosis and Talus Osteochondral Defect in the Ankle Joint. A Case Study

Synovial chondromatosis has an unknown aetiology and is a benign lesion especially seen in joints like the knee and hip. However, it is extremely rare in the ankle joint. A review of the literature shows that ankle joint chondromatosis is usually treated by arthrotomy. However, excision of loose bodies by arthroscopy in the ankle joint is not common. Arthroscopic surgery provides a wide visualisation area for excision of loose bodies, allowing for synovectomy and microfracture. Our patient was a 60-year-old female who presented to our clinic with primary osteochondromatosis and osteochondral defect. Our patient underwent arthroscopic excision of loose bodies, microfracture and synovectomy. Arthroscopic management can be successful in selected patients with synovial osteochondromatosis localized to the ankle joint.

Primary synovial chondromatosis of the talonavicular joint: A case report

Synovial chondromatosis developes by metaplasia of the synovial cells in the synovium of joints, and is a benign synovial tumor with multiple cartilaginous nodules. It is most commonly found in single and large joints, such as the knee, hip, and shoulder. Occurrence in the foot and ankle is uncommon, although there have been previous reports in the orthopedic and radiological literature of primary synovial chondromatosis in the subtalr, calcaneocuboid, naviculocuneiform, and metatarsaophalangeal joints. To our knowledge, occurrence in the talonavicular joint is even rarer, with only one report in the literature to date. Here, we report a case of synovial chondromatosis of the talonavicular joint, alongside a review of the literature.

A Novel Complication of the Dall-Miles Cable Grip System Mimicking Recurrent Synovial Chondromatosis: A Case Report and Review of the Literature

CASE

A 25-year-old man with synovial chondromatosis of the hip was treated with a synovectomy through a transtrochanteric approach; the repair was made with use of a Dall-Miles cable. Approximately 13 years later, the patient returned with a massive bursal reaction and a cyst containing "rice bodies." Although the physical examination and imaging were suggestive of recurrent synovial chondromatosis, the bursal reaction actually represented a novel complication of the Dall-Miles system.

CONCLUSION

When a patient who has had prior orthopaedic instrumentation presents with pain and imaging that demonstrates formation of a bursal cyst, a cyst containing rice bodies secondary to bursal irritation by the implant should be considered.

Patellar Subluxation With Early-Phase Synovial Chondromatosis of the Knee

Primary synovial chondromatosis is a rare, benign, monoarticular disease process that affects the synovial membrane of the joint, the synovial sheath, or the bursa around the joint. The etiology is unknown, but it has been associated with trauma in some cases. Although it is a benign lesion, if left untreated, it may lead to early secondary osteoarthritis of the joint. The knee joint is affected in 50% to 65% of cases, followed by the elbow and the hip. This article reports a 30-year-old active woman who presented to the author's clinic with a large infrapatellar mass that caused lateral subluxation of the patella, swelling, and episodic pain with crepitations 14 months after direct trauma to the knee. Clinical examination, magnetic resonance imaging, and arthroscopy revealed a large infrapatellar mass causing lateral subluxation of the patella with no loose bodies. Hoffa's disease, para-articular osteochondroma, and early-phase synovial chondromatosis were considered in the differential diagnosis. The histopathologic and clinical features were consistent with early synovial chondromatosis. The patient underwent local excision of the mass through a medial parapatellar arthrotomy. At 5 years of follow-up, she had no recurrence of the lesion or progression of the disease. Early diagnosis of synovial chondromatosis with local excision offers a reliable cure. However, long-term follow-up is advised because of the high recurrence rates as well as the risk of metaplastic transformation.

Relapsing Polychondritis Concomitant With Synovial Chondromatosis of the Temporomandibular Joint

Relapsing polychondritis (RP) is a rare, multisystem autoimmune disease characterized by inflammation, structural damage, and impaired function of cartilaginous tissues throughout the body. In the craniofacial region, this rare disease has been reported to affect structures of the ear and nose; however, reports of temporomandibular joint (TMJ) involvement are scarce. A second uncommon disorder of cartilage is synovial chondromatosis (SC), a progressive and proliferative disorder of the synovial membrane associated with the formation of variably sized cartilaginous and calcified loose bodies, often causing dysfunction of the joints and enlargement of the joint capsule. It commonly affects the larger joints; TMJ involvement is uncommon. We present the case of a 45-year-old woman with previously diagnosed RP in whom right TMJ pathology subsequently developed, undergoing arthroscopy and biopsy followed by arthroplasty, which was proved to be SC, likely due to her autoimmune disease. To our knowledge, this is the first case describing concomitant SC of the TMJ presumably from pre-existing RP.

[Generalised Form of Synovial Chondromatosis of the Knee Joint]

This study describes a diagnostic and therapeutic algorithm in a 53-year-old male patient who was diagnosed with a synovial chondromatosis of the knee joint extending to the popliteal fossa and soft tissues around the knee. Because of the presence of massive nodules, the patient was indicated for total synovectomy, with removal of pathologically changed cartilaginous tissue, performed by combined anterior and posterior approaches to the knee joint. Despite complete removal of the synovium and loose cartilage bodies and the patient's pain relief in the post-operative time, three years after the operation new problems appeared. Magnetic resonance imaging (MRI) confirmed a relapse of synovial chondromatosis and the patient was indicated for revision surgery of the knee joint. The results of physical examination and MRI scans, and intra-operative findings in the patient are reported.

KEY WORDS

synovial chondromatosis, total synovectomy, direct anterior and posterior approaches to the knee joint.

Giant Solitary Synovial Chondromatosis Mimicking Chondrosarcoma: Report of a Rare Histologic Presentation and Literature Review

Synovial chondromatosis is a benign lesion of the synovium, and giant solitary synovial chondromatosis (GSSCM) is a rare presentation of it. In this article, we describe clinical, imaging, and pathologic features of a hip GSSCM with an unusual histologic presentation.

Extra and Intra-articular Synovial Chondromatosis

Synovial chondromatosis is not so rare intra-articular condition secondary to synovial metaplasia, that affects the knee joint. Extra-articular synovial chondromatosis however is an extremely rare condition that usually involves the synovial sheath or bursa of the foot or hand. We present two cases of synovial chondromatosis, one intra and one extra-articular. The first case was a 25 year old lady who presented with pain, swelling and restricted range of motion of left knee and was found to have an intra-articular synovial chondromatosis which was treated successfully by joint debridement. The second case was that of a 22 year old man who presented with right knee pain and was diagnosed to have an extra-articular synovial chondromatosis of his right medial hamstring tendon sheath, excision of which resulted in complete relief of symptoms.

Arthroscopic Management of Synovial Osteochondromatosis of the Hip

Synovial osteochondromatosis is a benign metaplasia of the synovium resulting in the formation of osteocartilaginous nodules within the synovial lining. At presentation, radiographs typically reveal these nodules to have broken free from the synovial lining, becoming loose bodies residing in the free space of the affected joint. These fragments readily receive the necessary nutrients for continued growth from the synovial fluid in which they reside. Controversy exists over the management of the disease. Some physicians call for arthrotomy with a complete synovectomy, whereas others vouch for a minimally invasive arthroscopic approach. In the case described here, the surgeon decided on hip arthroscopy to treat synovial osteochondromatosis in a 61-year-old woman. All but one loose body that was adherent in the anterior hip capsule was successfully removed and the patient recovered promptly. This case highlights the importance of hip arthroscopy and its usefulness not only in treating conditions such as synovial osteochondromatosis, but also in accurately diagnosing them. Recognition and management of hip conditions such as synovial osteochondromatosis through arthroscopy result in minimally invasive treatment and decreased morbidity and may markedly accelerate patient rehabilitation. It is the authors' belief that this unique case further suggests the practicality of using hip arthroscopy to successfully treat synovial osteochondromatosis.

Technical tip: Dorsal transmetatarsal approach to intermetatarsal and deep plantar lesions

Synovial and chondromatous lesions can extend dorsally, intermetatarsally and deep into the vault of the longitudinal and transverse plantar arches of the foot. The lesions may prove difficult to excise even with combined approaches. Two cases where a transmetatarsal approach by excision of the base of the third metatarsal enabled successful complete excision of the lesions are presented.

LEVEL OF EVIDENCE

Level V, expert opinion.

Arthroscopic treatment for synovial chondromatosis of the subacromial bursa associated with partial rotator cuff tear

Synovial chondromatosis is characterized by benign synovial proliferation that leads to chondral or osteochondral foci formation. In this case report, a right-handed female suffered from progressively worsening pain and limited mobility of forward elevation, abduction and external rotation in her right shoulder. A shoulder arthroscopy was conducted, during which, thickened bursal synovium and several loose bodies were observed, associated with bursal side tear of rotator cuff. A thorough synovectomy, subacromial debridement and acromioplasty were conducted. The pathological findings were consistent with synovial chondromatosis. After systematic rehabilitation, the patient had relief of shoulder pain and full range of motions in 14-months follow-up.

LEVEL OF EVIDENCE

Case report, Level IV.

Odyssey of an elbow synovial chondromatosis

Synovial chondromatosis of the elbow is an uncommon condition. However, a chondrosarcoma arising from the former is remarkably rare. The authors report a case of an elbow chondrosarcoma secondary to synovial chondromatosis in a 38-year-old woman. Before the development of chondrosarcoma, the patient underwent 3 operations and 3 sessions of radiosynovectomy because of continuous recurrence of synovial chondromatosis on the left elbow. After the last radiosynovectomy, magnetic resonance imaging and biopsy showed a grade II chondrosarcoma secondary to synovial chondromatosis. The patient underwent further surgery and custom-made arthroplasty because of aseptic loosening of the prosthesis. Four months after the last intervention, 3 subcutaneous nodes appeared on the patient's elbow and were histologically found to be a recurrence of chondrosarcoma (grade III). Amputation by disarticulation of the shoulder was performed in addition to biopsy of another subcutaneous node on the abdomen. The biopsy showed metastasis of chondrosarcoma. At final follow-up, the patient had lung metastasis 7 years after the initial diagnosis. A reason for the manifestation of primary synovial chondromatosis and its progression to chondrosarcoma has not been found. Synovial chondromatosis progressing to chondrosarcoma in the elbow was reported in only 1 case, with no clear initial diagnosis. The role of radiosynovectomy in the development of chondrosarcoma is unknown, and no reports have described the treatment of elbow synovial chondromatosis. Although synovial chondromatosis is benign, its metaplastic nature is a marker of possible malignancy, especially with signs of recurrence and aggression. The role of radiosynovectomy in malignant changes should be examined in future studies.

Synovial chondromatosis of pes anserine bursa secondary to osteochondroma

Osteochondromas are common benign bone tumors. Synovial chondromatosis is a benign cartilaginous metaplasia that occurs in the synovium. The authors describe a unique case of synovial chondromatosis developing in the pes anserine bursa secondary to an underlying osteochondroma of the proximal medial tibia. It is unusual to see both of these processes occurring simultaneously in 1 location. After appropriate consent was obtained, the patient's case was reviewed. A 17-year-old boy presented with a painless mass in the medial aspect of the right leg. Initial imaging of the right leg showed a cartilaginous-appearing lesion arising from the tibia and several distinct additional cartilaginous masses in the adjacent soft tissue. After 16 months of observation, the patient began to have increasing pain in the region of the lesion. The patient underwent surgery for excision of suspected synovial chondromatosis of the right pes anserine bursa and osteochondroma of the proximal right tibia. Postoperatively, the patient had complete resolution of symptoms and regained full range of motion of the knee. He returned to full activities, including walking and running. Osteochondromas are common benign bone tumors. Synovial chondromatosis is a benign synovial metaplastic cartilaginous proliferation that occurs primarily in joints, but can occur in any synovial-lined space. In this case report, the authors describe a unique occurrence of both of these lesions simultaneously. The treatment was excision of the osteochondroma and resection of the chondromatosis lesions, which resulted in an excellent outcome.

Synovial osteochondromatosis in the subacromial bursa mimicking calcific tendinitis: sonographic diagnosis

Synovial osteochondromatosis is an idiopathic benign metaplasia of the synovial membrane rarely found in an extra-articular bursa. We describe the case of a 55-year-old woman with synovial osteochondromatosis in the subacromial bursa mimicking calcific tendinitis. Plain radiographs showed a radiopaque mass over the middle facet of the greater tuberosity, suggesting calcific tendinitis. Sonography, however, showed a loose body in the subacromial bursa, and no evidence of calcification inside the rotator cuff.

Large synovial osteochondromatosis arising from the interphalangeal joint of the thumb: a case report and review of the literature

A 38-year-old woman presented with a very large synovial chondromatosis arising from the interphalangeal joint of the thumb. The tumor surrounded the interphalangeal joint and its size was approximately 3 cm. The range of motion was almost fused. Plain radiographs showed an extra-osseous tumor shadow with calcifications. The patient had no local recurrence at one year of follow-up after marginal resection of the tumor and synovectomy. Because this case showed no osteoarthritic changes, it can be classified as primary synovial chondromatosis with a tumor-like nature. Based on the clinical course and pathological report, our synovial chondromatosis case can be classified as Milgram stage 3. Our case report is unique in three respects: i) origin from the interphalangeal joint of the thumb, ii) a single lump of mass and iii) extremely large size. To our knowledge, a similar type of synovial chondromatosis has not been previously reported in the English literature.

Pancarpal synovial and tenosynovial chondromatosis in a 65-year-old man: a highly unusual presentation of a common condition

Synovial chondromatosis is a rare, benign, metaplastic condition in which synovial tissue becomes hyperplastic, and foci of cartilaginous metaplasia develop in the synovial membranes of joints, bursae, or tendon sheaths. Involvement is most commonly monoarticular. The large joints are most commonly affected, with the knee accounting for more than half of all cases. There are isolated reports of synovial chondromatosis occurring in the small joints of the wrist and hand. However, it is very uncommon for the disease to involve multiple different synovial structures. We report the case of a middle-aged man with pancarpal synovial chondromatosis with involvement of numerous bony, articular, and tenosynovial structures within the hand and wrist.