Gluteal Region Flashcards
Muscles
State the origin and insertion of the gluteus maximus muscle.
Origin:
Upper part of the area behind the posterior gluteal line.
Back of the sacrum and coccyx.
Back of the sacrotuberous ligament.
Insertion:
3/4 of the muscle are inserted into the iliotibial tract.
The lower deep 1/4 is inserted into the gluteal tuberosity of the femur.
State the nerve supply of the gluteus maximus.
Inferior gluteal nerve.
State the actions of the gluteus maximus.
It is the main extensor of the hip joint.
Its upper fibres abduct the thigh.
Through the iliotibial tract, it stabilises the femur on the tibia during standing when the quadriceps are relaxed.
State the origin and insertion of gluteus medius.
Origin: the gluteal surface of the ilium, in the area limited by the iliac crest and posterior and medial gluteal lines.
Insertion: into the posterosuperior angle and the oblique ridge on the lateral surface of the greater trochanter.
State the nerve supply of the gluteus medius.
Superior gluteal nerve.
State the relations of the gluteus medius.
Anteriorly: covered by skin, superficial fascia and deep fascia.
Posteriorly: covered by gluteus maximus.
Deep surface:
- Gluteus minimus.
- Superior gluteal nerve.
- Deep division of the superior gluteal artery (and accompanying veins).
State the origin and insertion of the gluteus minimus.
Origin: the gluteal surface of the ilum in the area bounded by the middle and inferior gluteal lines.
Insertion: into an impression on the anterior surface of the greater trochanter.
State the nerve supply of the gluteus minimus.
Superior gluteal nerve.
State the actions of the glutei medius and minimus.
They are the main abductors of the thigh.
Their anterior fibres are medial rotators of the thigh.
The muscles of both sides contract reflexly during walking in an alternating manner to prevent tiliting of the pelvis to the unsupported side when the leg is raised from the ground.
State the relations of the gluteus minimus.
Covered completely by the gluteus medius with the superior gluteal n and deep division of superior gluteal a (and veins) intervening.
Deeply, it is related to the reflected head of rectus femoris and capsule of hip joint.
State the origin and insertion of tensor fascia latae.
Origin: anterior part of the outer lip of iliac crest.
Insertion: iliotibial tract.
State the nerve supply of tensor fascia latae.
Superior gluteal nerve.
State the actions of the tensor fascia latae.
Helps in abduction and medial rotation of the thigh.
Through the iliotibial tract, it helps in: extension of the knee.
lateral rotation of the leg.
With the gluteus maximus, it helps in stabilising the femur on the tibia during standing when the quadriceps is relaxed.
With the glutei medius and minimus, it also plays a role in stabilising the pelvis during walking.
State the origin and insertion of the iliotibial tract.
Origin:
It is the thickened lateral part of the fascia lata (deep fascia of the thigh).
Its upper part splits to receive the insertions of the tensor fascia latae and superficial 3/4 of gluteus maximus.
Insertion:
The tract gradually narrows inferiorly to be attached to an oblique ridge on the front of the lateral condyle of the tibia.
State the actions of the iliotibial tract.
Through their insertions to the tract, the gluteus maximus and tensor fascia latae help in stabilising the femur on the tibia during standing when the quadriceps is relaxed.
State the origin and insertion of the piriformis.
Origin:
Pelvic (ventral) surface of the middle 3 pieces of the sacrum.
Few fibres arise from the gluteal surface of the ilium just above the greater sciatic foramen.
Insertion:
The muscle passes out through the greater sciatic foramen and converges into a tendon which is inserted into the upper border of the greater trochanter.
State the nerve supply of the piriformis.
Twigs from the ventral rami of the 1st and 2nd sacral nerves in the pelvis.
State the action of the piriformis muscle.
When the hip joint is extended, it rotates the thigh laterally.
When the hip is flexed, it abducts the thigh.
It also helps in controlling other mvts at the hip joints.
State the origin and insertion of obturator internus.
Origin:
Front and lateral wall of the pelvic cavity, including
Inner surface of the obturator membrane.
Inner margin of obturator foramen.
Wide area above and behind the obturator foramen.
Insertion:
The fibres of the muscle converge to form a tendon which passes out of the lesser sciatic foramen and changes its direction on the bone with a bursa intervening.
The tendon passes laterally and forwards to be inserted into the medial surface of the greater trochanter.
State the nerve supply of the obturator internus.
N to obturator internus from the sacral plexus.
State the actions of obturator internus.
Lateral rotation of the thigh. It helps in controlling other mvts at the hip joint.
State the origins and insertion of the gemilli muscles.
Origins:
Superior gemillus: upper margin of the lesser sciatic notch.
Inferior gemillus: lower margin of the lesser sciatic notch.
Insertion:
They pass laterally to be inserted into the tendon of obturator internus.
State the nerve supplies of the gemilli muscles.
Superior gemillus: receives a twig from the n to obturator internus.
Inferior gemillus: receives a twig from the n to quadratus femoris.
State the origin and insertion of quadratus femoris.
Origin: lateral border of the ischial tuberosity.
Insertion:
Quadrate tubercle.
Lower part of the intertrochanteric crest.
