Thumb carpometacarpal or basal joint arthritis is the second most common location for osteoarthritis in the hand. It mainly affects women over 50years of age. Basal joint arthritis causes pain, loss of strength during pinch grips, and eventually stiffness and progressive deformity of the thumb column. Conservative treatment must be implemented first. It aims to spare the joint by using standardized methods. It must be initiated as soon as pain starts, not once the deformity has settled in. There is broad agreement that surgery is indicated when pain relief is not achieved after at least 6months of conservative treatment. The available surgical techniques can be classified as joint-sparing (extra-articular) and joint-sacrificing (intra-articular). The former consists of trapeziometacarpal stabilizing ligament reconstruction, subtraction osteotomy of the first metacarpal and thumb carpometacarpal denervation. The latter consists of trapeziometacarpal fusion, trapeziectomy (and its variants) and implant arthroplasty. Except in very specific cases, trapeziectomy and trapeziometacarpal implant arthroplasty with a total joint prosthesis or an interposition implant are the two main surgical techniques for treating basal joint arthritis. After reviewing the pathophysiology and the diagnosis of thumb basal joint arthritis, we will provide an overview of the available treatment options, with emphasis on the accepted surgical strategies in 2023.

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