[Metacarpophalangeal joint arthroscopy].

[OBJECTIVE] Pain reduction in the affected metacarpophalangeal joint (MP joint) by synovectomy, loose body extraction and resection of intraarticular scars.

[INDICATIONS] Synovitis in rheumatoid arthritis (RA) not responding to antirheumatic treatment, primary and secondary degenerative arthritis, osteochondral lesions, loose bodies, foreign bodies, capsular contracture, septic arthritis, posttraumatic arthralgia (old collateral ligament injury), intraarticular fractures.

[CONTRAINDICATIONS] Established biomechanical changes in RA such as ulnar deviation and palmar subluxation with extensor tendon luxation of the MP joint. Advanced radiologic changes in degenerative arthritis. Joint instability in posttraumatic conditions. Fresh skin lesion near portals.

[SURGICAL TECHNIQUE] Longitudinal traction of the affected finger in a Chinese finger trap. The joint is filled with Ringer solution. Placement of a radial and ulnar dorsal portal at joint space level, through the extensor hood, at the dorsal border of the collateral ligaments. Diagnostic arthroscopy. In case of insufficient visibility (i.e., bulky synovitis in RA) "blind" shaving in the dorsal recess at first. Completion of synovectomy under sight. If necessary additional ablation of synovial tissue by a radiofrequency (RF) electrosurgical system. Use of arthroscope (1.9 mm) with a 30° angle of vision and shaver (aggressive cutter; 2.0 mm). Low-suction drain, soft padded dressing.

[POSTOPERATIVE MANAGEMENT] Immediate postoperative mobilization for the full range of finger movement.

[RESULTS] In 106 MP joint arthroscopies from 2009-2011, very high patient satisfaction was achieved. Best results were obtained in RA, even in advanced radiologic changes (Larsen stages 1-3). Only in Larsen stage 4 results were rated lower. In early stages of degenerative arthritis (Kellgren-Lawrence 0-2), patient satisfaction was also very high, however decreased rapidly with increasing degree of radiologic changes. The results in posttraumatic cases are promising.