Background
Tarsal tunnel syndrome (TTS) is an entrapment neuropathy of the tibial nerve within fibrous tunnel on the medial side of the ankle. The most common cause of TTS is idiopathic. This is a retrospective study to define the lectrophysiological characteristics of idiopathic TTS.
Methods: We reviewed the medical and electrophysiological records of consecutive patients with foot sensory symptoms referred to electromyography laboratory. Inclusion of patients was based on clinical findings suggestive of TTS. Among them, patients with any other possible causes of sensory symptoms on the foot were excluded. Control data were obtained from 19 age-matched people with no sensory symptoms or signs. Routine motor and sensory nerve conduction study (NCS) including medial plantar nerve (MPN) using surface electrodes were performed.
Results: Twenty one patients (13 women, 8 men, 9 unilateral, 12 bilateral) were enrolled to have idiopathic TTS (total 31 feet). Tinel

Background
Carpal tunnel syndrome (CTS) and tarsal tunnel syndrome (TTS) are thought to share a similar pathophysiology,compression of the median and plantar nerve by the carpal tunnel and flexor retinaculum. A few reports introduced the relationshipbetween idiopathic CTS and TTS without definite evidence of coexistence. The current study was designed to analyze theelectrophysiologic characteristics of combined idiopathic CTS and TTS by comparing with each idiopathic CTS or TTS.Methods: We retrospectively collected patients with combined idiopathic CTS and TTS (CTS-TTS group) from June 2001 toFebruary 2009. Patients with each idiopathic CTS or TTS were collected as controls. Electrophysiologic data of median and plantarnerves were compared between CTS-TTS group and controls. Results: CTS-TTS group was composed of 31 patients. Control groupof each CTS or TTS were 50 CTS and 49 TTS patients. In comparison of median nerve conduction study between CTS-TTS groupand CTS control group, decreased compound muscle action potential amplitude (p<0.001), decreased median sensory nerve actionpotential amplitude (p<0.001) and sensory nerve conduction velocity at finger stimulation (p=0.013) were prominent in CTS-TTSgroup. Decreased medial plantar sensory nerve action potential amplitude (p=0.034) was indicated when CTS-TTS groups and TTScontrol group were compared. Conclusions: If the electrophysiology study of patients with CTS or TTS was suggestive of severe degreeof nerve injury, concerns about the possibility of combined CTS and TTS would be helpful.

Background
Carpal tunnel syndrome (CTS) and tarsal tunnel syndrome (TTS) are thought to share a similar pathophysiology,compression of the median and plantar nerve by the carpal tunnel and flexor retinaculum. A few reports introduced the relationshipbetween idiopathic CTS and TTS without definite evidence of coexistence. The current study was designed to analyze theelectrophysiologic characteristics of combined idiopathic CTS and TTS by comparing with each idiopathic CTS or TTS.Methods: We retrospectively collected patients with combined idiopathic CTS and TTS (CTS-TTS group) from June 2001 toFebruary 2009. Patients with each idiopathic CTS or TTS were collected as controls. Electrophysiologic data of median and plantarnerves were compared between CTS-TTS group and controls. Results: CTS-TTS group was composed of 31 patients. Control groupof each CTS or TTS were 50 CTS and 49 TTS patients. In comparison of median nerve conduction study between CTS-TTS groupand CTS control group, decreased compound muscle action potential amplitude (p<0.001), decreased median sensory nerve actionpotential amplitude (p<0.001) and sensory nerve conduction velocity at finger stimulation (p=0.013) were prominent in CTS-TTSgroup. Decreased medial plantar sensory nerve action potential amplitude (p=0.034) was indicated when CTS-TTS groups and TTScontrol group were compared. Conclusions: If the electrophysiology study of patients with CTS or TTS was suggestive of severe degreeof nerve injury, concerns about the possibility of combined CTS and TTS would be helpful.

Background
Tarsal tunnel syndrome (TTS) is an entrapment neuropathy that occurs in the ankle. Previous studies reportedthat this disease was due to physiologic factors and structural lesions in the ankle or foot. The authors investigated the causativefactors of TTS and their frequency via operative findings. The diagnostic value of MRI was also evaluated based onthe concordance between the operative findings and the MRI findings. Methods: This study was performed in retrospectiveby using medical record of the patients who underwent operations with TTS from August 2003 to May 2010. Physical examination,nerve conduction study, and MRI were conducted on patients who visited department of neurology or orthopedicsurgery due to pain and sensory abnormality of their ankle and foot. Results: 34 patients underwent the operation. Ganglionaccounted for the largest portion of the operative findings. In addition, varicose veins, intrinsic foot muscle hypertrophy, tenosynovitis,and fascia thickening were mainly observed. Of the 34 patients, 33 patients underwent pre-operative MRI, of whom18 patients showed MRI findings consistent with the operative findings. Conclusions: Space-occupying lesions accounted forthe majority of the causative factors in TTS patients who underwent the surgical treatment. In this study, the MRI appeareduseful for identifying causes of TTS.