A Rare Case of Flexor Digitorum Accessorius Longus Muscle Presenting as Tarsal Tunnel Syndrome

Tarsal tunnel syndrome (TTS) is a relatively uncommon nerve entrapment neuropathy. Many pathologies are reported aspossible causes for TTS. The diagnosis of TTS can be difficult and often missed. We present a rare case of TTS due toan accessory flexor digitorum longus muscle. Together with a high index of suspicion, MRI is the investigation of choice inmaking the diagnosis. These patients are best managed with excision or transposition of the flexor digitorum accessoriuslongus (FDAL) and neurolysis of the posterior tibial nerve and its branches.Level of evidence: IV