In addition to innervating major muscle groups, each of the major peripheral nerves originating from the lumbar and sacral plexuses carries general sensory information from patches of skin (Fig. 6.19). Sensation from these areas can be used to test for peripheral nerve lesions:
The femoral nerve innervates skin on the anterior thigh, medial side of the leg, and medial side of the ankle.
The obturator nerve innervates the medial side of the thigh.