The lateral rotator group is a group of six small muscles of the hip which all externally (laterally) rotate the femur in the hip joint. It consists of the following muscles: piriformis, gemellus superior, obturator internus, gemellus inferior, quadratus femoris and the obturator externus.^[1]

All muscles in the lateral rotator group originate from the hip bone and insert on to the upper extremity of the femur. The muscles are innervated by the sacral plexus (L4-S2), except the obturator externus muscle, which is innervated by the lumbar plexus.^[2]

This group does not include all muscles which aid in lateral rotation of the hip joint: rather it is a collection of ones which are known for primarily performing this action. Other muscles that contribute to lateral rotation of the hip include:

• Gluteus maximus muscle (lower fibres)
• Gluteus medius muscle and gluteus minimus muscle when the hip is flexed (become medial rotators when hip is extended)
• Psoas major muscle
• Psoas minor muscle
• Sartorius muscle

• Dissection of lateral rotator group (obturator externus hidden under quadratus femoris muscle) seen from the back
• Muscles of thigh as seen from the front
• Cross section of pelvic region

• Hip anatomy