Anatomy of the Butt (buttocks)

buttocks AnotomyThe gluteal region is an area of the human anatomy that is placed posteriorly to the pelvic girdle, at the proximal tip of the femur. The muscles in this area provide movement to the lower limb at the hip joint.
The muscles of the gluteal area can be classified into two unique groups.

Superficial abductors and extenders – A group of large muscles that abduct and the femur, this includes the tensor fascia lata, gluteus minimus, gluteus medius and gluteus maximus.

Deep Lateral rotators – A group od smaller muscles that operate to the laterally rotate the femur. These muscles include the obturator internet, gemellus inferior, gemellus superior, performs, and quadratus.

buttocks Anotomy1The Superficial Muscles

The superficial muscles in the gluteal region comprise of the tensor fascia lata and three glutei. The function mainly to abduct and extend the lower limb a the hip joint.

Gluteus Maximus
The Gluteus Maximus is the most significant of the gluteal muscles. The Gluteus Maximus is also the most superficial producing the shape of the buttocks.

Attachments: Originates from the gluteal( posterior) outside of the ilium, sacrum, and coccyx. It slants across the buttock at 35-degree angles, then inserts into the iliotibial tract and the gluteal tuberosity fo the femur.

Actions. Gluteus Maximus is the main extensor of the thigh and helps with the lateral rotation. Although it is only used when force is requered, such as climbing or running.

Innervation . The inferior gluteal nerve.

The gluteus maximus including the gluteus medius and gluteus minimus, are referred to as gluteal muscles and occasionally referred informally to as the glutes, is the main extensor muscle of the hip. It is the largest and most exterior of the three gluteal muscles and consists of a large portion of the shape and form of each side of the hips. The gluteus is the thick fleshy mass, in a quadrilateral shape, forms the prominence of the buttocks.

The large size is one of the most characteristic features of the muscular system in humans attached as it is with the power of maintaining the trunk in the erect posture. Other primates have much flatter hips and can not sustain standing erectly.

buttocks Anotomy3Gluteus Medius

The gluteus medius muscle is fan-shaped and extends between the gluteus maximus and the minimus. It is similar is shaped and function to the gluteus minimus. It is similar in shape and purpose to the gluteus minimus.

Attachments Originate from the gluteal surface of the ilium and inserts into the surface of the greater trochanter.
Actions. Abduct and medially turns the lower limb. During movement, it secures the pelvis, preventing the pelvic drop of the opposite limb.

Innervation. The superior gluteal nerve.

The gluteus medius muscle starts or originates on the outer surface of the ilium among the iliac crest and the posterior gluteal line, and the anterior gluteal line below, the gluteus medius also originate form the gluteal aponeurosis that covers it outer surface.

The fibers of the muscle converge into a strongly flattened tendon that inserts on the lateral surface of the greater trochanter. The muscles tendon inserts int an oblique ridge that runs downward and forwards on the lateral surface of the greater trochanter.
Gluteus Minimus

The gluteus minimus is the deepest and diminutive of the superficial gluteal muscles. It is similar is shape and function to the gluteus medius.

Attachments Originate from the ilium and unites to form a tendon inserting to the anterior side of the greater trochanter.

Actions abduct and medially rotates the lower limb. During Locomotion, it secures the pelvis, preventing the pelvic drop of the opposite limb.

Innervation, Superior gluteal nerve.

Tensor Fascia Lata

Tensor Fascia Lata is a small superficial muscle which lies toward the anterior edge of the iliac crest. It operates to tighten the fascia lata and abducts and medially rotates the lower limb.

Attachments: Originates from the anterior iliac crest, attaching to the anterior superior iliac spine ASIS. It inserts into the iliotibial tract, that attaches to the lateral condyle of the tibia.

Actions Assist the gluteus medius and minimus in an abduction and medial circumrotation of the lower limb. It also performs a supportive role in the gait cycle

Innervation Superior gluteal nerve.

The Deep Muscles
The deep gluteal muscle is a set of smaller muscles, located underneath the gluteus minimus. The general action of these muscles is to rotate the lower limb laterally. They also stabilize the hip joint by pulling’ the femoral head into the acetabulum of the pelvis.


The piriformis muscles is a key landmark in the gluteal region. It is the most superior of the deep muscles.

Attachments: Starts from the anterior surface of the sacrum. It then travels inferolateral, through the greater sciatic foramen, to insert into the greater trochanter of the femur.

Actions Lateral rotation and abduction
Innervation: Nerve to piriformis.

Obturator internet
The obturator internet forms the lateral walls of the pelvic cavity. In some texts the obturator internet and the Gemelli, muscle is considered as one muscle- the recipes coxae.

Attachments: Originates from the pubis and ischium at the obturator foramen. It moves through the lesser sciatic foramen and attaches to the greater trochanter of the femur

Actions Lateral rotation and abduction

Innervation Nevre to obturatto internus.

The Gemelli – Superior and Inferior

The Gemelli are two thin and triangular muscles. They are divided by the obturator internet tendon.

Attachments: The superior gemellus muscle begins from the ischial spine, the inferior from the ischial tuberosity. They both connect to the larger trochanter of the femur.
Actions: Lateral rotation and abduction.
Innervation: The superior gemellus muscle is innervated by the nerve to obturator internet, the inferior gemellus is innervated by the nerve to quadratus femoris.
Quadratus Femoris

The quadratus femoris is a flat, square-shaped muscle. It is the most minor of the deep gluteal muscles, positioned below the Gemelli and obturator internus.

Attachments: The quadratus starts from the lateral side of the ischial tuberosity, and attaches to the quadrate tuberosity on the intertrochanteric crest.
Actions: Lateral rotation.

Innervation: Nerve to quadratus femoris.

Bone Structure

The pelvis is the portion of your skeleton which forms the shape of the hips and support for your buttocks; This is one part of the, but that can not change.

Females have a wider pelvis than males o allow for childbirth and his cause the femur or thigh bones to also form wider. The effect is a wider-shaped butt associated with female characteristics.

Health Life Media Team