TMJ osteoarthrosis and internal derangements are in close connection, representing a substantial portion of temporomandibular disorders. The authors wish to underline the role of surgery in the treatment of this degenerative disease to improve function and to alleviate pain. A 63 year-old woman suffering from closed-lock with reduced opening movements was accepted in our Department in March, 1995. Clinical and radiological evaluations showed bilateral closed lock and severe TMJ osteoarthrosis. Occlusal, pharmacological and physical therapy were performed for one year, without results. Bilateral condylectomy and diskectomy with arthroplasty were carried out. Immediate muscular rehabilitation after surgery was performed by the patient. Follow-up 3, 6, 12 months after surgery were carried out. Full opening movements and reduction of pain were obtained 20 days after surgery. The patient, followed-up one year after surgery, presented effective mandibular movements and adequate amelioration of clinical picture. TMJ surgery in association with physical therapy represents in selected cases an adequate procedure for the treatment of TMJ degenerative disease.