Sonographic and electrophysiologic findings in patients with meralgia paresthetica

Objective: This study was aimed to demonstrate the usefulness of ultrasonography in the diagnosis of meralgia paresthetica (MP). Methods: Clinical data, sensory nerve conduction study and sonographic findings of 23 patients with unilateral MP were analyzed retrospectively. Twelve healthy subjects were recruited for the optimal cut-off value for the cross-sectional area of LFCN to diagnose MP using receiver operating characteristic curves. Results: The median value of the cross-sectional area of LFCN in healthy subjects was 3mm² and in the affected and unaffected sides in patients with MP, they were 11 and 6.5mm² around the anterior superior iliac spine level. The optimal cut-off value for the diagnosis of MP was 5mm². The location of LFCN on the affected side was superior to the inguinal ligament in 12 out of 23 cases (50%). Conclusion: Ultrasonography is useful in the diagnosis of MP as a supplemental diagnostic tool, which gives important information about the morphologic changes that occur in the LFCN and its course. Significance: To the best of our knowledge, this is the first report to suggest that describe the cutoff value of the cross-sectional area of LFCN for the diagnosis of MP using ultrasonography.