Synovial chondromatosis associated with experimental osteoarthritis in adult monkeys.

This report describes the synovial response to temporomandibular joint disc perforation in an experimental animal model. Histologic examination revealed the presence of marked synovial membrane hypertrophy in all experimental joint recesses. Gradual transformation of synovial islands from a cellular to a metaplastic stage, with chondroid or even osteochondroid-containing tissue also was seen. The cartilage was arranged in a lobular pattern with intervening fibrous septae within the synovial islands. These synovial islands were observed in the anterior recess of three joints and in the posterior recess of another joint. The experimental findings suggest a relation between synovial chondromatosis and osteoarthritis.