The value of inching technique in evaluating the peroneal nerve entrapment at the fibular head.

The peroneal nerve palsy at the fibular head is quite common but often difficult to diagnose both clinically and electrophysiologically. The purpose of this study was to evaluate the usefulness of the inching in mononeuropathy of the peroneal nerve at the fibular head. Recording from extensor digitorum brevis muscle the nerve was stimulated supramaximally at 1 cm intervals starting 2 cm distal and ending 8 cm proximal to the fibular head. Forty-six patients were examined: the inching was modified in 32 patients. In five of these the motor conduction using conventional method was normal, but the inching was normal or borderline in fourteen patients with reduced conduction velocity across the fibular head. Despite some limitations, the inching can be useful in evaluating patients with suspected palsy of the peroneal nerve at the fibular head.