Reconstruction of Chronic Boutonniere Deformity of the Thumb in a Golf Player.

We present the case of a professional golf player who gradually developed a boutonniere deformity of the thumb due to chronic repetitive injury to the thumb and was treated with reconstruction of its insertion onto the proximal phalangeal base. The athlete showed an insertion variation of the extensor pollicis brevis, where some slips attached onto the extensor hood and the other slips ran along with the extensor pollicis longus to the distal phalanx, providing no slip to the proximal phalanx. The slips inserting to the distal phalanx were transferred to the base of the proximal phalanx and sagittal band reconstruction. As a result, the boutonniere deformity of the thumb fully recovered with satisfactory outcomes.Level of Evidence: Level V.