title: Hindfoot endoscopy for accessory flexor digitorum longus and flexor hallucis longus tenosynovitis.
abstract: We present a case report involving the flexor digitorum accessorius longus (FDAL) tendon which travels through a fibro-osseous tunnel together with the flexor hallucis longus (FHL) tendon, causing a stenosing tenosynovitis. The patient was admitted with posteromedial ankle pain and diagnosed clinically as FHL tenosynovitis. We found two tendons in the tunnel during hindfoot endoscopy. The stenosis was relieved by endoscopic debridement. After the operation, we checked the MRI images and observed two tendons. We concluded that the accessory tendon was the FDAL. Two years later the patient was admitted with the same symptoms. We excised the FDAL muscle and the patient's symptoms resolved. The FDAL muscle is a cause of FHL tenosynovitis. Because of its variability and mostly asymptomatic nature, it may not be noticed it on an MRI scan. Hindfoot endoscopy is a safe tool for the diagnosis of this condition and curative treatment is afforded by excision of the FDAL muscle.
authors.affiliation: Istanbul University, Cerrahpasa Medical Faculty, Orthopaedics and Traumatology Department, Istanbul, Turkey.
authors.forename: Tahir
authors.initials: T
authors.lastname: Ogut
authors.forename: Egemen
authors.initials: E
authors.lastname: Ayhan
mesh_terms: D001182:Arthroscopy; D005534:Foot Diseases / Q000473:pathology / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D013710:Tendons / Q000473:pathology; D013717:Tenosynovitis / Q000473:pathology / Q000601:surgery*