Arthroscopic Resection Arthroplasty for Scaphotrapeziotrapezoid Arthritis

The scaphotrapeziotrapezoid (STT) joint is located in the radial part of the midcarpal joint, and the scaphoid contact area changes dynamically during wrist motion. Arthroscopic resection arthroplasty of the STT joint is indicated for the treatment of idiopathic and symptomatic STT osteoarthritis (OA) without DISI-like deformity that is refractory to nonsurgical treatment. Presence of midcarpal joint degeneration involving the lunocapitate joint and dorsally subluxated midcarpal joint should be a contraindication for this procedure. The radial midcarpal arthroscopy portal is the viewing portal, and the ulnar–STT portal is used as a working portal from the ulnar side of the EPL tendon. Because the scaphoid is in an extension stance in the sagittal plane and in an upright stance in the coronal plane in patients with STT OA, contact area of the STT joint is located at the distal pole of the scaphoid in wrist neutral position. However, the resection area should include both the distal pole and dorsal slope of the scaphoid. Arthroscopic distal scaphoid resection can reduce pain and improve functional outcomes with low risk for surgical complications for early- to mid-stage STT OA in patients without DISI deformity. Excessive resection of the distal scaphoid of >3 mm may result in postoperative carpal malalignment and suboptimal outcomes.