A Missing Flexor Hallucis Longus Muscle and Tendon in a Young Female Patient: A Case Report of a Rare Anomaly.

Anatomic variations of the long flexor tendons of the foot are not common. Tendinous bands connecting the flexor hallucis longus and the flexor digitorum longus are well known and have even been classified. Although the congenital absence of the flexor pollicis longus in the hand is well known, we found no reports of the absence of the flexor hallucis longus in the foot. We describe the case of a 32-year-old female who stepped on a crystal ashtray and transected the flexor hallucis tendon arising from the flexor digitorum longus. During surgery, the absence of the proper flexor hallucis longus muscle and tendon became apparent. This anomaly appears to be extremely rare, and its clinical importance is unknown, although our patient reported no functional problems before the accident.