Clinical and radiographic outcomes of metacarpophalangeal joint pyrolytic carbon arthroplasty for osteoarthritis

Abstract

Purpose: To determine the effectiveness of pyrolytic carbon arthroplasty for the management of primary osteoarthritis of the metacarpophalangeal joint.

Methods: A retrospective review of 11 pyrolytic carbon arthroplasties for osteoarthritis of the metacarpophalangeal joint, performed by a single surgeon, was conducted. All patients returned for clinical assessment at a minimum of 2 years after surgery. Evaluation included range of motion, pain and functional scores, and patient satisfaction. Validated outcome measures included the Michigan Hand Questionnaire and Quick Disabilities of the Arm, Shoulder, and Hand. Radiographs were assessed for implant failure, loosening, migration, and subsidence.

Results: The average follow-up was 4 years (minimum 2 y). The arc of motion significantly improved from 62° before surgery to 76° after surgery. Grip strength decreased slightly compared to the contralateral side (average, 3 kg). The average pain score was 1 on a 10-point visual analog scale. All but 1 patient were fully satisfied at final follow-up. All patients who were working before surgery returned to work after surgery. The Michigan Hand Questionnaire average score was 80, and the Quick Disabilities of the Arm, Shoulder, and Hand average score was 22. Two patients experienced persistent, asymptomatic squeaking and clicking, and 1 patient reported extensor tendon subluxation. One joint had conversion to arthrodesis for continued, unexplained pain. All surviving implants had a surrounding lucency on radiographs. The average subsidence was 3 mm; there was no implant migration, fracture, or dislocation.

Conclusions: Pyrolytic carbon arthroplasties of the metacarpophalangeal joint resulted in satisfactory outcomes at average 4-year follow-up, with improved joint motion, good pain relief and satisfaction, and few complications. Radiographic outcomes revealed a consistent, asymptomatic surrounding lucency with no evidence of implant failure or migration.