Surgical repair of an abductor Hallucis muscle herniation with tarsal tunnel syndrome: A rare case report with a long term follow-up

Abstract

Atramatic, painful herniation of the abductor hallucis muscle is rare. During the period of writing this case study, we found less than ten published articles on abductor hallucis muscle anatomy and only three case reports on the abnormalities within the abductor hallucis muscle. Familiarity with the condition is needed for early diagnosis, surgical intervention, and prevention of recurrence. It is also important to have an experienced musculoskeletal radiologist to identify this unique pathology. This is a unique case study of a young active female who presented with an abductor hallucis muscle herniation, tarsal tunnel syndrome, and ligamentous laxity. She suffered from foot pain and was misdiagnosed for multiple years. She began living with normal foot pain during her exercise activities. Her symptoms began to worsen with numbness and tingling. After failing modification of shoe gear, physical therapy, resting, and offloading, she was further worked up with imaging. This MRI was evaluated by a musculoskeletal radiologist. It was discovered that she has a large muscle belly, with a retinaculum injury, and impingement along the tarsal tunnel. She was successfully treated with a surgical repair of the herniation, application of synthetic dynamic matrix graft, and decompression of the tarsal tunnel at the porta pedis. She had a complete resolution of symptoms in 6 weeks and she was followed up for 3 years with no recurrence. The purpose of this case report is to add to the body of literature on treatment options for muscle herniation in foot and ankle surgery.