Muscles of the Gluteal Region PDF

Muscles of the Gluteal Region Aizaz Demonstrator Surgical KMU-IPMS Peshawar Gluteal Region The gluteal region is an anatomical area located posteriorly to the pelvic girdle, at the proximal end of the femur. The muscles in this region move the lower limb at the hip joint. The mu...

Muscles of the Gluteal Region Aizaz Demonstrator Surgical KMU-IPMS Peshawar Gluteal Region The gluteal region is an anatomical area located posteriorly to the pelvic girdle, at the proximal end of the femur. The muscles in this region move the lower limb at the hip joint. The muscles of the gluteal region can be broadly divided into two groups: Superficial abductors and extenders – group of large muscles that abduct and extend the femur. Includes the gluteus maximus, gluteus medius, gluteus minimus and tensor fascia lata. They mainly act to abduct and extend the lower limb at the hip joint. Deep lateral rotators – Includes the quadratus femoris, piriformis, gemellus superior, gemellus inferior and obturator internus. The deep gluteal muscles are a set of smaller muscles, located underneath the gluteus minimus. The general action of these muscles is to laterally rotate the lower limb. They also stabilise the hip joint by ‘pulling’ the femoral head into the acetabulum of the pelvis The arterial supply to these muscles is mostly via the superior and inferior gluteal arteries – branches of the internal iliac artery. Venous drainage follows the arterial supply. Gluteus Maximus The gluteus maximus is the largest muscle in the body. It is also the most superficial, producing the shape of the buttocks. Origin: Outer surface of ilium, sacrum, coccyx, sacrotuberous ligament. Insertion: Iliotibial tract and gluteal tuberosity of femur. Nerve Supply: Inferior gluteal nerve (L5,S1,2) Action: Extends and laterally rotates hip joint; through iliotibial tract, it extends knee joint Gluteus Medius The gluteus medius muscle is fan-shaped and lies between to the gluteus maximus and the minimus. It is similar in shape and function to the gluteus minimus Origin: Outer surface of ilium Insertion: Lateral surface of greater trochanter of femur Nerve Supply: Superior gluteal nerve (L5, S1) Action: Abducts thigh at hip joint; tilts pelvis when walking to permit opposite leg to clear ground Gluteus minimus The gluteus minimus is the deepest and smallest of the superficial gluteal muscles. It is similar in shape and function to the gluteus medius Origin: Outer surface of ilium Insertion: Anterior surface of greater trochanter of femur Nerve Supply: Superior gluteal nerve (L5,S1) Action: Abducts thigh at hip joint; tilts pelvis when walking to permit opposite leg to clear ground Tenser fasciae lata Tensor fasciae lata is a small superficial muscle which lies towards the anterior edge of the iliac crest. It functions to tighten the fascia lata, and so abducts and medially rotates the lower limb Origin: Iliac crest Insertion: Iliotibial tract Nerve Supply: Superior gluteal nerve (L4,L5) Action: Assists gluteus maximus in extending the knee joint Piriformis  The piriformis muscle is a key landmark in the gluteal region. It is the most superior of the deep muscles  The piriformis lies partly within the pelvis at its origin. It emerges through the greater sciatic foramen to enter the gluteal region. Its position serves to separate the superior gluteal vessels and nerves from the inferior gluteal vessels and nerves Origin: Anterior surface of sacrum Insertion: Upper border of greater trochanter of femur Nerve Supply: 1st and 2nd sacral nerves (L5, S1,S2) Action: Lateral rotator of thigh at hip joint Obturator internus  The obturator internus forms the lateral walls of the pelvic cavity.  The obturator internus is a fan-shaped muscle that lies within the pelvis at its origin. It emerges through the lesser sciatic foramen to enter the gluteal region. The tendon is joined by the superior and inferior gemelli and is inserted into the greater trochanter of the femur. Origin: Inner surface of obturator membrane Insertion: Upper border of greater trochanter of femur Nerve Supply: Sacral plexus( L5, S1) Action: Lateral rotator of thigh at hip joint Gemellus superior The gemelli are two narrow and triangular muscles. They are separated by the obturator internus tendon. Origin: Spine of ischium Insertion: Upper border of greater trochanter of femur Nerve Supply: Sacral plexus (L5, S1) Action: Lateral rotator of thigh at hip joint Gemellus Inferior Origin: Ischial tuberosity Insertion: Upper border of greater trochanter of femur Nerve Supply: Sacral plexus (L5, S1) Action: Lateral rotator of thigh at hip joint Quadratus Femoris The quadratus femoris is a flat, square-shaped muscle. It is the most inferior of the deep gluteal muscles, located below the gemelli and obturator internus. Origin: Lateral border of ischial tuberosity Insertion: Quadrate tubercle of femur Nerve Supply: Sacral plexus (L5, S1) Action: Lateral rotator of thigh at hip joint