Synovial chondromatosis of the temporomandibular joint with extension to the middle cranial fossa.

A rare case of synovial chondromatosis with extension to the middle cranial fossa is reported. Synovial chondromatosis, a benign disorder characterized by multiple cartilaginous, free-floating nodules that originate from the synovial membrane is not exclusive to the temporomandibular joint (TMJ). This condition is commonly seen in the axial skeleton and can involve multiple joints. In this case, synovial chondromatosis of the TMJ led to complete bony erosion of the glenoid fossa extending into the middle cranial fossa. Although plain radiographs showed the involvement of the joint, Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) provided more detailed information about the lesion in all three dimensions. This case demonstrates the value of CT and MRI in both the diagnosis and treatment planning. A review of previously reported cases of synovial chondromatosis with cranial extensions is included.