Synovial chondromatosis in the inferior compartment of the temporomandibular joint: different stages with different treatments.

PURPOSE: To discuss a new classification and the treatment principles of synovial chondromatosis (SC) in the inferior compartment of the temporomandibular joint (TMJ). PATIENTS AND METHODS: Five cases of SC in the inferior compartment were treated in an open manner between January 2008 and May 2011. Each case had different clinical and radiologic aspects and was treated with different surgical therapies. SC in the inferior compartment of the TMJ is classified into 3 stages. All patients were evaluated by computed tomography, magnetic resonance imaging, and clinical manifestations preoperatively and postoperatively. RESULTS: There were 3 kinds of manifestation modes from radiologic findings. Case 1 was in stage 1, in which multiple loose bodies are noted without bony erosion. This patient was treated by removal of loose bodies and affected synovium. Case 2 was in stage 2, in which multiple calcified nodules were conglutinated to the condyle; the condyle was enlarged with pressure erosions. This patient was treated by condylectomy and reconstruction with costochondral graft. Case 3, case 4, and case 5 were all in stage 3, in which the condyle was destroyed as a result of pressure erosions or by direct bony invasion of the mass and the inferior surface of the disc was involved. These patients were treated by condylectomy together with discectomy, as well as reconstruction with costochondral graft and pedicled deep temporal fascial fat flap. No recurrence occurred. The height of the ramus and the occlusion were maintained in the same condition as preoperatively. CONCLUSIONS: Our new classification of SC in the inferior compartment of the TMJ can better guide clinical treatment.

A case of synovial chondromatosis of the TMJ: treatment based on stage of the disease.

A patient with synovial chondromatosis of the temporomandibular joint extending to the preauricular skin, parotid, and infratemporal fossa was operated and followed with a stable remnant, for 2 years postoperatively. In light of literature and what the authors have learned from this case, the authors emphasize stage of the disease as a risk factor for recurrence. The long history of symptoms, calcified and conglomerated radiological appearance of the lesion, and extensive involvement of the joint and periarticular area of this case indicate a late-stage disease in which the metaplastic activity dwindles. For late stages, the authors suggest a conservative approach that will only provide symptom relief and prevent secondary joint deformity to avoid potential complications and morbidities of a more extensive surgery.

Primary synovial chondromatosis and synovial chondrosarcoma: a pictorial review.

This article illustrates the imaging characteristics of primary synovial chondromatosis (PSC) using 20 cases referred to a tertiary orthopaedic oncology centre. Three quarters of patients presented with a large intra-articular soft tissue mass and a suspected clinical and radiological diagnosis of malignancy made in the referring centres. Radiographs demonstrated fine cartilaginous mineralisation in the soft tissue masses in 85% cases and bone erosions were shown on MR imaging in 80%. Malignant transformation to chondrosarcoma was proven in 2 cases with longstanding disease. There were no specific MR features to distinguish these cases with malignant change from PSC alone. Primary synovial chondromatosis should be considered in the diagnosis of the monarticular presentation of an intra-articular soft tissue mass, particularly in the presence of superficial bone erosions and signal voids due to the mineralisation.

Magnetic resonance imaging of cartilaginous tumors: a retrospective study of 79 patients.

OBJECTIVE: Hyaline cartilaginous tumors are characterized by extremely high signal intensity on T2-weighted images. Recently, some distinctive MR features of cartilaginous bone tumors were reported in small series. Low signal intensity septa surrounding high signal intensity cartilage lobules were seen on T2-weighted images in low-grade chondrosarcomas. On spin-echo T1-weighted images after Gd contrast injection, marked 'septal' or 'ring-and-arc' enhancement was observed in low-grade chondrosarcomas and enchondromas. The purpose of this study was to determine sensitivity and specificity of these MR findings in diagnosis of cartilaginous tumors, and to assess the value of MR in diagnostic workup of these lesions. MATERIALS AND METHODS: Retrospective evaluation of MR findings in 79 cartilaginous tumors and in 79 non-cartilaginous tumors. All lesions were biopsy proven. Each MR examination was independently reviewed by two experienced radiologists without knowledge of clinical data, radiographic and/or CT findings, or histological diagnosis. All lesions were evaluated for morphology (lobular or non-lobular), presence of a high signal intensity mass on T2-weighted images, presence of low signal intensity septa separating high signal intensity lobules on T2-weighted images, and evidence of septal ('ring-and-arc') enhancement. RESULTS: None of the reviewed parameters is useful in diagnosing osteochondromas. Since osteochondromas have a characteristic appearance on plain radiography, the value of MR imaging in the workup of these lesions remains limited. MR findings in enchondromas have a low specificity and a low sensitivity. Low-grade chondrosarcomas, often hard to diagnose on plain radiography and difficult to differentiate from enchondromas, are characterized by the MR tandem of 'low signal intensity septa on T2-weighted images' together with 'septal or ring-and-arc enhancement' (sensitivity 92.3%, specificity 76.5%). High-grade chondrosarcomas are easily recognized on plain radiography. CONCLUSIONS: In differentiating cartilaginous from non-cartilaginous tumors, MR features are highly specific but lack sensitivity. Grading potentials of MR parameters are promising due to the high accuracy in diagnosing low-grade chondrosarcomas.

[Synovial osteochondromatosis. Therapeutic indications based on a histological classification]. / Ostéochondromatose synoviale. Indications thérapeutiques orientées par une classification histologique.

The surgical treatment of synovial osteochondromatosis fluctuates between the desire of doing the most complete synovectomy to avoid the formation of new loose bodies, and the technical possibilities of realising it without compromising the stability and the expansion of the ulterior mobility of the articulation. The histological examination of 44 operatory pieces allow us to suggest a histological classification of 4 evolutive stages based on the aspect of the synovial and without taking into consideration the existence or not of loose bodies which can exist in all stages. The surgical operation should be large in the stage of full fluorescence, it can be limited in the regression stage. This evolutive diagnostic can be done through the histological examination of the biopsy obtained by arthroscopy.