Sonographic and electrophysiologic findings in patients with meralgia paresthetica

ObjectiveThis study was aimed to demonstrate the usefulness of ultrasonography in the diagnosis of meralgia paresthetica (MP).MethodsClinical 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.ResultsThe median value of the cross-sectional area of LFCN in healthy subjects was 3 mm2 and in the affected and unaffected sides in patients with MP, they were 11 and 6.5 mm2 around the anterior superior iliac spine level. The optimal cut-off value for the diagnosis of MP was 5 mm2. The location of LFCN on the affected side was superior to the inguinal ligament in 12 out of 23 cases (50%).ConclusionUltrasonography 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.SignificanceTo 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.

► The optimal cut-off value for the cross-sectional area of lateral femoral cutaneous nerve to diagnose meralgia paresthetica (MP) was 5 mm2.
► The location of lateral femoral cutaneous nerve on the affected side was superior to the inguinal ligament in 12 out of 23 cases.
► 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 lateral femoral cutaneous nerve and its course.