Nerve
Obturator nerve
Lumbar-plexus nerve serving most thigh adductors
High-yield
The adductor part of adductor magnus belongs mainly to the obturator pathway; its hamstring part belongs to the tibial division of the sciatic nerve. A distinct medial-thigh skin territory is variable and may be absent.
Overview
The obturator nerve descends from the lumbar plexus along the pelvic sidewall and passes through the obturator canal. Its anterior and posterior branches supply much of the medial thigh and carry sensory fibers from the hip and knee.
Reference facts
- Root value
- Anterior divisions of the L2–L4 ventral rami in the lumbar plexus
- Course
- Emerges from the medial psoas border, follows the lateral pelvic wall and reaches the thigh through the obturator canal; division into anterior and posterior branches occurs near this passage
- Motor
- Adductor longus, adductor brevis, the adductor part of adductor magnus, gracilis and obturator externus; a contribution to pectineus can occur
- Sensory
- Articular supply to hip and knee; a variable skin contribution near the medial thigh and knee that is not present in everyone
Clinical correlation
Pelvic surgery or local compression can injure the obturator nerve and weaken thigh adduction. Normal skin sensation does not exclude such an injury because its cutaneous contribution is inconsistent.
Frequently asked questions
What are the roots of the obturator nerve?
Anterior divisions of the L2–L4 ventral rami in the lumbar plexus.
What muscles does the obturator nerve supply?
Adductor longus, adductor brevis, the adductor part of adductor magnus, gracilis and obturator externus; a contribution to pectineus can occur.
What is the sensory distribution of the obturator nerve?
Articular supply to hip and knee; a variable skin contribution near the medial thigh and knee that is not present in everyone.
What is the course of the obturator nerve?
Emerges from the medial psoas border, follows the lateral pelvic wall and reaches the thigh through the obturator canal; division into anterior and posterior branches occurs near this passage.