Alternative treatment for varus instability of the hallux interphalangeal joint: A case report.

Forefoot injuries are commonly caused by sport-related activities and are often around the metatarsophalangeal joints. The hallux interphalangeal (IP) joint is anatomically stable; therefore, injuries to this joint are considered to be rare compared with those to the metatarsophalangeal joint. Instability of the hallux IP joint has rarely been reported in barefoot contact sports, and its treatment has not been sufficiently explored.This study investigated chronic varus instability of the hallux IP joint. We performed a surgical reconstruction owing to conservative treatment failure. A good surgical outcome was achieved by reconstruction of the collateral ligament using the 4th extensor tendon-a promising alternative treatment option for this type of injury. This method indicated no morbidity outside the site of surgery and was more cost-effective than reconstruction using an allograft.