Chronic sesamoiditis of the thumb: pathomechanics and treatment.

Entrapment of the sesamoids within the metacarpophalangeal joint can result in irreducible dislocations; however, dysfunction from trauma-induced, chronic sesamoiditis is unfamiliar. Twenty-five patients with intractable posttraumatic pain of the metacarpophalangeal joint of the thumb are reported. The mechanisms of the palmar plate injury included hyperextension, direct compression, shear forces, and lateral stress. Sesamoidectomy achieved good results in 80% of patients as evidenced by return to preinjury activities. Residual joint stiffness was present in 20% of patients, and 8% had significant residual pain. Traumatic microtears appear to produce pathologic findings in the perisesamoid tendon and/or sesamoid-metacarpal articulation.