A ganglion is a cyst-like lesion comprised of a fibrous capsule containing hyaluronic acid. In general, such lesions occur in the intramedullary juxtaarticular regions of the wrist, ankle, and knee joints. We report an extremely rare case of intraosseous ganglion of the condylar head.
A 23-year-old woman was referred to our clinic on November 22, 1999 because of radiating pain around the right temporomandibular joint. She had no history of trauma. Pain increased on mouth opening and occlusion. The range of mouth opening was 33 mm between the upper and lower incisors.
On computed tomography (CT), the surface of the right condylar head was flattened and partly defective; the bone marrow showed irregular resorption. The condition of the bone deteriorated on subsequent CTscans, and magnetic resonance images showed the lesion to be an irregular mass, measuring 0.8cm × 0.6cm with a clearly defined margin. Right condylectomy incloding the articular disc was performed to make a pathological diagnosis on October 25, 2000.
Histopathologically, the condylar head contained cell-rich fibrous tissue associated with increased synovial tissue, including mucous changes, cystic changes, or both. The diagnosis was an intraosseous ganglion.
As of 14 months postoperatively, there has been no recurrence or dysfunction.
