The nerve descends medial to psoas major to the obturator canal where it divides into anterior and posterior divisions. The anterior division exits from the obturator canal to enter the medial compartment of the thigh. The posterior division exits through obturator externus.
Medial compartment of thigh
The adductor brevis muscle separates the divisions of the obturator nerve:
Branches of the anterior division include:
- articular branch to hip joint
- adductor brevis
- adductor longus
- cutaneous branch: supplies skin along mid-portion of medial thigh
Branches of the posterior division supply:
- obturator externus
- adductor magnus (pubic part)
- articular branch to knee joint: pierces oblique popliteal ligament
Branch of the anterior division contributes to the subsartorial nerve plexus (near the insertion of adductor longus).
Injury to the obturator nerve weakens hip adduction and contributes to instability. Irritation of the nerve may result in pain in the medial thigh/knee.
Pathology can include direct trauma (i.e. childbirth) or pelvic pathology (i.e. tumor).
Nerve entrapment can occur within the obturator canal or as the nerve pierces the obturator externus muscle.
- Musculus obturatorius externus
- Musculus gracilis
- Musculus adductor magnus
- Musculus pectineus
- Musculus adductor longus
- Musculus adductor brevis