Obturator nerve

The obturator nerve is a peripheral nerve that arises from the lumbar plexus and includes nerve fibers from the spinal cord segments L2-L4[^1].

Anatomy

The obturator nerve travels medially from the psoas major muscle down to the sidewall of the small pelvis to the obturator canal, through which it reaches the leg. The obturator nerve gives off a muscular branch to the obturator externus muscle and then divides into a deep branch and a superficial branch.

Superficial Branch

The superficial branch runs between the adductor longus muscle and the adductor brevis muscle, and ends by giving off a cutaneous branch to the distal area of the medial thigh surface as a terminal branch.

Deep Branch

The deep branch runs over the obturator externus muscle and then deeply into the adductor magnus muscle.

Function

The obturator nerve provides motor innervation to the thigh adductors. This includes the adductor longus muscle, adductor brevis muscle, pectineus muscle, gracilis muscle, obturator externus muscle, and adductor magnus muscle. Sensory innervation is provided by the obturator nerve to the medial part of the thigh.

Clinical Significance

An impairment of the obturator nerve leads to a restriction of the adductor muscles, which affects standing and gait. Affected patients may, depending on severity, be unable to cross the affected leg over the other.

Illustration