Scaphotrapezial joint arthroscopy: a palmar portal.

PURPOSE

Arthroscopy of the scaphotrapezial trapezoid (STT) joint is performed traditionally through a dorsal radial midcarpal portal. This portal allows visualization of the dorsal rim of the STT joint but is difficult to approach owing to lack of surface landmarks and it passes close to the radial artery and nerve. The purpose of this study was to assess the safety, ease of access, and visualization of the STT joint through a palmar portal.

METHODS

Five cadaveric wrists were dissected initially to identify the anatomy around the palmar aspect of the STT joint and to identify a safe route for an arthroscopic portal. A further 5 cadaveric wrists then were used to confirm the efficacy of the portal.

RESULTS

A palmar portal to the STT joint can be established 3 mm ulnar to the abductor pollicis longus tendon, 6 mm radial to the scaphoid tubercle, and midway between the radial styloid and base of the first metacarpal.

CONCLUSIONS

A palmar arthroscopic portal to the STT joint can be identified readily because of the palpable surface landmarks, improves the visualization of its articular surface compared with a dorsal portal because of the orientation of the joint, is safe, and provides a second portal through which therapeutic interventions may be considered.