Medial femoral cutaneous nerve conduction.

Medial femoral cutaneous nerve (MFCN), a sensory branch of the femoral nerve, supplies the skin on the anterior medial aspect of the thigh and knee. A conduction study for this nerve is described. A recording electrode was placed anterior-medially in the thigh and 14 cm distal to the stimulating cathode that was placed immediately lateral to the femoral artery just below the inguinal ligament. Sixty-four nerves of 32 adults with a mean age of 40 yr (range, 21-56) were tested. The latencies to the onset and peak were 2.4 +/- 0.2 and 2.9 +/- 0.2 ms, respectively. The amplitude of baseline to negative peak was 4.9 +/- 1.0 microV. The conduction velocity calculated by the distance divided by the onset latency was 60 +/- 5 m/s. We conclude that the MFCN is accessible for electrophysiologic evaluation, which may help in diagnosing the MFCN or femoral neuropathy.