Tarsal Tunnel Syndrome: Electrophysiological Study

Abstract

Tarsal Tunnel Syndrome (TTS) is a compression neuropathy of the posterior tibial nerve. This study highlights the sensory nerve conduction velocity as a superior diagnostic index for TTS.

Introduction

Tarsal Tunnel Syndrome, or TTS, is analogous to carpal tunnel syndrome but occurs in the foot. Despite numerous clinical studies, electrophysiological studies on TTS are scarce, making this research significant for its improved diagnostic techniques.

Clinical Symptoms

TTS primarily manifests as burning pain and paresthesias, abnormal sensations such as tingling or numbness, affecting the toes and the sole of the foot. These symptoms are typically exacerbated by activities such as prolonged standing or walking and are relieved by rest.

A crucial clinical sign for diagnosing TTS is Tinel's sign, an electric tingling sensation felt when tapping the posterior tibial nerve at the ankle. This sign is positive in the majority of studied cases. Additionally, objective sensory loss in the territory of the terminal branches of the posterior tibial nerve can be observed, which bolsters the diagnosis of TTS.

Nocturnal symptoms, often noted in about a quarter of the patients, also indicate the presence of TTS. Clinical evaluation may also reveal weakness in toe flexion and, in advanced cases, atrophy of the intrinsic muscles of the foot, although these latter symptoms are less frequently observed.

Materials and Methods

Seventeen patients were studied to determine the motor and sensory nerve conduction velocities. The study included measuring terminal latencies and sensory nerve potential across specific foot nerves.

Results

The study revealed prolonged terminal latency and sensory nerve conduction abnormalities in patients with TTS, confirming the utility of NCV as a superior diagnostic index for this syndrome.

Discussion

The findings suggest that sensory nerve conduction velocity in the lateral and medial plantar nerves is crucial for effectively diagnosing TTS. The study highlights the importance of NCV in detecting this rare neuropathy.

Conclusion

This electrophysiological approach provides a significant improvement over previous diagnostic methods for Tarsal Tunnel Syndrome, offering a more objective and sensitive measure through sensory nerve conduction velocity.