Scaphotrapeziotrapezoid osteoarthritis: From the joint to the patient.

Scaphotrapeziotrapezoid osteoarthritis (STT OA) is common and often associated with thumb basal joint arthritis. Pain at the base of the thumb on the volar aspect and during resisted extension is characteristic of symptomatic STT OA. If conservative treatment fails, surgical treatment may be offered. In case of STT OA, treatment may range from arthrodesis to trapeziectomy (isolated or associated with ligament reconstruction and/or interposition). Any preoperative intracarpal instability (DISI) can be exacerbated by resecting more than 3 or 4 mm of the distal pole of scaphoid. For peritrapezial osteoarthritis, trapeziectomy is the logical solution, but it exposes the patient to known complications: loss of strength, long recovery, trapeziometacarpal impingement. Initial treatment of thumb basal joint arthritis by arthroplasty is also an option. Treatment of both sites is also possible by interposition of pyrocarbon implants. In all cases (isolated or associated STT OA) and no matter the technique chosen, maintaining the scaphoid height (arthrodesis, resection < 3 mm and/or associated interposition) and performing oblique trapezoidal osteotomy (to prevent scaphoid-metacarpal impingement) are the two crucial elements of surgical treatment.