METACARPOPHALANGEAL JOINT ARTHROPLASTY BASED ON THE OSSEOINTEGRATION CONCEPT

The osseointegration concept has been used for fixation of 68 MP joint endoprostheses in 31 patients operated on at the Department of Hand S urgery, Malmo General Hospital during the period 1988-1992. The indica tions were rheumatoid arthritis (50 joints), primary osteoarthrosis (t hree joints), post-traumatic osteoarthrosis (three joints), post-traum atic osteoarthrosis (five joints), post-infectious osteoarthrosis (sev en joints) and joint deformities secondary to spastic conditions (thre e joints). The average follow-up time was 2.5 years (6-54 months). The surgical procedure included resection of the joint followed by introd uction of screw-shaped titanium fixtures into the bone marrow cavities of the metacarpal and the phalangeal base. Rheumatoid cases usually r equired grafting of cancellous bone and marrow from the iliac crest. A t the same time a flexible constrained silicone spacer was connected t o the titanium fixtures in such a may as to allow later replacement of the spacer if accessory. The average active range of motion (ROM) was 57 degrees in the rheumatoid cases and 50 degrees in all cases. Radio logical and clinical osseointegration occurred in every case, and ther e were no clinical signs of loosening. In four cases (6%) there was a fracture of the joint mechanism. Patient satisfaction was high, with p ain relief, increased range of motion, improved hand function and good cosmetic appearance.