Clinical utility of sensory nerve conduction of medial femoral cutaneous nerve

Introduction: In this investigation we report on the clinical utility of sensory nerve conduction studies of the medial femoral cutaneous (MFC) nerve. Methods: Sensory nerve conduction of the MFC nerve was assessed in 22 patients for whom this test was considered clinically necessary. Results: MFC nerve conduction was abnormal in 4 cases of MFC neuropathy. The most common cause was iatrogenic in 14 femoral neuropathy cases. MFC nerve conduction showed absent or low-amplitude sensory nerve action potential (SNAP) in 13 cases, with femoral motor nerve conduction abnormal in 5 cases. In 2 cases with acute lumbar plexopathy, the MFC SNAP was absent unilaterally. MFC nerve conduction was normal in 1 case with diabetic lumbar radiculopathy and in another case with postpolio syndrome. Conclusion: Assessment of MFC nerve conduction is extremely useful in the diagnosis of femoral neuropathy, medial femoral cutaneous neuropathy, and lumbar plexopathy.