Deterioration of trapeziometacarpal arthritis due to trigger thumb: A biomechanical evaluation

Patients with trigger thumb and trapeziometacarpal joint arthritis accompanied by swanneck deformity of their first rays find that their arthritic pain becomes worse whenever their thumbs ''catch.'' Six hands with adduction contracture and arthritis of the trapeziometacarpal joint are studied biomechanically and demonstrate significantly excessive shear forces (p<0.01) around their trapeziometacarpal joint relative to six normal hands. Increased pain with deformity suggests aggressive treatment of trigger thumb in cases such as these.