Lateral rotator group

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]

Lateral rotator group
The lateral rotator group and the gluteus minimus muscle, posterior view
Structures surrounding right hip joint
Details
OriginAt or below the acetabulum of the ilium
InsertionOn or near the greater trochanter of the femur
ArteryInferior gluteal artery, lateral sacral artery, superior gluteal artery
NerveObturator nerve, nerve to the Piriformis, nerve to quadratus femoris
ActionsLateral rotation of hip
AntagonistGluteus minimus muscle, gluteus medius muscle
Anatomical terms of muscle

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]

Individual muscles

Muscleorigininsertioninnervation[2]
Piriformis muscleAnterior surface of sacrum between and laterally to the anterior sacral foraminaSuperior boundary of greater trochanterNerve to the piriformis (S1-S2)
Gemellus superior muscleIschial spineUpper edge of Obturator internus muscle tendon (indirectly greater trochanter)Nerve to obturator internus (L5-S2)
Obturator internus muscleMedial surface of obturator membrane and the surrounding boneMedial surface of greater trochanterNerve to obturator internus (L5-S2)
Gemellus inferior muscleJust above the tuberosity of the ischiumLower edge of Obturator internus muscle tendon (indirectly greater trochanter)Nerve to quadratus femoris (L4-S1)
Quadratus femoris muscleLateral edge of the tuberosity of the ischiumIntertrochanteric crestNerve to quadratus femoris (L4-S1)
Obturator externus muscleLateral surface of obturator membrane and the ischiopubic ramusTrochanteric fossaPosterior branch of obturator nerve (L3-L4)

Other lateral rotators

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:

Additional images

See also

References

  1. MedicalMnemonics.com: 833 3471 657
  2. Bojsen-Møller, Finn; Simonsen, Erik B.; Tranum-Jensen, Jørgen (2001). Bevægeapparatets anatomi [Anatomy of the Locomotive Apparatus] (in Danish) (12th ed.). p. 365. ISBN 978-87-628-0307-7.
  • Glutealregion at The Anatomy Lesson by Wesley Norman (Georgetown University)
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