Checkrein Syndrome.

Checkrein syndrome is a rare condition affecting the flexor hallucis longus (FHL) tendon as a result of either surgery or trauma. Checkrein syndrome is defined as the occurrence of hallux malleus upon dorsiflexion of the ankle, which is reduced upon plantarflexion of the ankle. The literature supports various treatments for this condition; however, lengthening of the FHL tendon remains the mainstay of treatment. In this case series, we describe two cases of checkrein syndrome with different etiologies: pilon fracture and gunshot wound to the leg. Both of these cases were successfully treated with FHL tendon lengthening, with one case requiring a hallux interphalangeal joint arthrodesis.