Human leg lumbar plexus. It supplies motor innervation to iliopsoas, pectineus, sartorius, and quadriceps; and sensory branches to the anterior thigh, medial lower leg, and posterior foot. The nerves of the sacral plexus pass behind the hip joint to innervate the posterior part of the thigh, most of the lower leg, and the foot. The superior (L4-S1) and inferior gluteal nerves (L5-S2) innervate the gluteus muscles and the tensor fasciae latae. The posterior femoral cutaneous nerve (S1-S3) contributes sensory branches to the skin on the posterior thigh. The sciatic nerve (L4-S3), the largest and longest nerve in the human body, leaves the
Fourth nerve palsy Fourth nerve palsy Fourth cranial nerve palsy also known as Trochlear nerve palsy, is a condition affecting Cranial Nerve 4 (IV), the Trochlear Nerve, which is one of the Cranial Nerves that causes weakness or paralysis to the Superior Oblique Muscle that it innervates. This condition often causes vertical or near vertical double vision as the weakened muscle prevents the eyes from moving in the same direction together. Because the fourth cranial nerve is the thinnest and has the longest intracranial course of the cranial nerves, it is particularly vulnerable to traumatic injury. To compensate for the double-vision resulting from