Piriformis

Description[edit | edit source]

Piriformis-muscle.jpg

Piriformis is a flat muscle and the most superficial muscle of the deep gluteal muscles. It is part of the lateral rotators of the hip (obturator internus, superior and inferior gemelli, quadratus femoris, obturator externus, and gluteus maximus). It leaves the pelvis through the greater sciatic notch, until its fixation reaches the superior margin of the greater trochanter.[1] It has a piramidal shape that lies almost parallel with the posterior margin of the gluteus medius.





Anatomy[edit | edit source]

Origin[1][edit | edit source]

  • Anterior aspect of the sacrum at the level of about S2 through S4
  • Sacrotuberous ligament
  • Periphery of the greater sciatic notch
[2]


Insertion[1][edit | edit source]

  • Superior and medial aspects of the greater trochanter

Nerve[1][edit | edit source]

  • Ventral rami of L5 and S1,2

Artery[3][edit | edit source]

  • Inferior gluteal artery, the lateral sacral artery, internal pudendal and the superior gluteal artery

Function[1][4][edit | edit source]

  • Lateral Rotation of the hip when it is extended;
  • Abduction fo the hip when it is flexed.

Clinical relevance[edit | edit source]

The piriformis muscle can be used to locate the scietic nerve. This nerve enters the gluteal region inferiorly to the piriformis.If the lateral rotators of the hip are tight they may exert pressure on the sciatic nerve, producing pain radiating into the lower extremity.[1][5] This is known as Piriformis Syndrome.

Another importance of this muscle is that it divides the gluteal region into a superior and inferior part. Therefore, it determines the name of the vessels anf nerves that supply the area (e.g. the superior gluteal nerve and vessels emerge superiorly to the piriformis, and the inferior gluteal nerve and vessels emerge inferiorly to the piriformis).[5]


Assessment[edit | edit source]

Palpation[edit | edit source]

It may be palpable indirectly through the gluteus maximus into the greater scietic notch.

Test[edit | edit source]

Piriformis Test

Treatment[edit | edit source]

Strengthening[edit | edit source]

Stretching[edit | edit source]

Manual techniques[edit | edit source]

Recent Related Research (from Pubmed)[edit | edit source]

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References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Oatis, C. A., (2009). Kinesiology : the mechanics and pathomechanics of human movement (2nd ed). Baltimore : Lippincott Williams & Wilkins.
  2. Michael Forrester. 201603 Visual Anatomy of the Hips Part 5 Lateral Hip Rotation Piriformis and more. Available from: https://www.youtube.com/watch?v=nq00pUMKlQo
  3. http://lowerlimbanatomy.wikispaces.com/Piriformis
  4. Moore, K. L., Dalley, A. F., Agur, A. M. R. (2014). Clinically oriented anatomy (7th ed).Philadelphia : Lippincott Williams & Wilkins.
  5. 5.0 5.1 http://teachmeanatomy.info/lower-limb/muscles/gluteal-region/