Entrapment neuropathy of the deep peroneal nerve, also recognized as anterior tibial nerve, typically occurs at the anterior ankle and dorsal foot. Compression of this nerve, which anatomically is inferior to the extensor retinaculum, is commonly referred to as anterior tarsal tunnel syndrome. This syndrome is rare and remains poorly diagnosed among clinical problems. A 25-year-old woman was referred to our outpatient clinic for a second opinion. She presented with a vague pain over the dorsomedial aspect of the foot which occasionally radiated into the first intertarsal space. Electromyography revealed moderate prolongation of distal latency and presence of accessory deep peroneal nerve (ADPN) with partially innervated extensor digitorum brevis. Our diagnosis was anterior tarsal tunnel syndrome, and surgical decompression of the anterior tarsal tunnel was performed. At the follow up three months later the symptoms where almost completely gone. One year after, there were still no symptoms.The ADPN is of great clinical and surgical importance. In the presence of ADPN, the lesion of the deep peroneal nerve spare the lateral portion of the EDB, leading to the possibility of an incorrect conclusion, as it was the case with our patient. subjectively silent weakness of the extensor digitorum brevis muscles. Patients may also complain of a burning sensation in the distribution of the DPN. The pain may be influenced by particular body positions during rest and ambulation. AATS of the DPN is an often underdiagnosed and poorly recognized clinical entity [5,9].
Case ReportA 25-year-old woman was referred to our out-patient clinic for a second opinion. She complained of a vague pain over the dorsomedial aspect of the foot (Figure 1) which occasionaly radiated into the first interosseal space.Occasionaly she complained of numbness within this area. Symptoms started nine months ago during the last trimester of her pregnancy. Her symptoms were often aggravated by physical activities especially with activities involving the left leg. She was diagnosed as "atypical left L5/Sl radiculopathy" at another university department. Examination showed no sensory loss and mild atrophy of left EDB.