Lower back pain is commonly due to irritation of the L5 and S1 nerve roots. Hip pain may result secondary to pain and spasm muscles of the lower back and all muscles that cross the hip. Patients may have trouble with external rotation of the hip due to pain and spasm of muscles that perform external rotation or from pain and spasm of muscles that perform internal rotation and thus limiting the performance of the external rotators.
This week, we shall talk about muscles that perform external rotation. To test these muscles, the patient should lie on his stomach and bend the knee up. The patient then turns the leg and foot in toward midline. This motion produces external rotation of the hip. To test the strength of the external rotators, the examiner must try to push the leg outward away from the midline. The hip external rotators are:
- gluteus maximus lower fibers (inferior gluteal nerve L5, S1 primarily S1)
- obturator internus (L5, S1, S2)
- superior gemellus (L5, S1, S2)
- inferior gemellus (L4, L5, S1)
- quadratus femoris (L4, L5, S1)
- obturator externus (obturator nerve, L2, L3, L4)
- adductor magnus, lower portion (sciatic nerve, L5, S1)
- adductor brevis (obturator nerve, L2, L3, L4)
- piriformis (S1, S2).
