Anatomy of Pelvis and Hips

Ischial Tuberosity

"Sit bones" that are located on the mist inferior aspect of the pelvis at the level of the gluteal fold (horizontal crease between the buttocks and thighs). Attachment site: Hamstrings Adductor Magnus Sacrotuberous Ligament

Perineum

A diamond-shaped area at the inferior aspect of the pelvis. It's framed by the Pubic Symphysis, the Ischial Tuberosities, and the Coccyx. The anterior side of the Pernieum (Urogenital Triangle) contains the external genitals and the posterior side (Anal Triangle) contains the Anus.

Sacrum

A large, triangle bone that is located at the inferior end of the vertebral column. It's made up of 4 or 5 vertebrae that are fused together. Humans have a larger # of sacral vertebrae because their entire weight of the body is transferred through the sacrum to the pelvis and legs. The 2 landmarks are the: Median Sacral Crest Edge of the Sacrum

Superior Ramus of the Pubis

It spans 45" from the Pubic Tubercle toward the AIIS. It forms the ridge and is deep to the Inguinal Ligament and a Neurovascular Bundle. Be cautious of the Femoral Artery (main supplier for blood for the thigh).

Pelic Floor

It's formed by the 2 Levator Ani and 2 Coccygeus Muscles. Combimed with their fascia, they form the funnel-shaped Pelvic Diaphragram. This spans to the inside floor of the pelvis. The Pelvic Floor supports the Abdominal and Pelvic Viscera (like the sigmoid colon and the rectum).

Edge of the Sacrum

It's located by following the lateral edge up towards the PSIS and down the coccyx. Attachment Sites: Gluteus Maximus Sacrotuberous Ligament

Inferior Ramus of the Pubis (IRP) and Ramus of the Ischium

Located along the inferior aspect of the pelvis and forms a bridge between the Pubic Crest and the Ischial Tuberosity. Attachment Sites: Gracilis Muscle (IRP) Adductor Brevis Muscle (IRP) Adductor Magnus Muscle (Both)

Gluteal Tuberosity

Located at the distal portion to the Posterior Surface of the Greater Trochanter. The Gluteal Tuberosity is relatively superficial and accessible, despite being surrounded by the Gluteus Maximus Tendon and Upper Fibers of the Vastus Lateralis Muscles.

Posterior Superior Iliac Spine (PSIS)

Located at the posterior end of the iliac crest. In most people, both PSISs are visibly identified by 2 small dimples at the base of the low back. It's not uncommon to locate the small nodules of fibrofatty tissue (embedded in the superficial fascia) as they can vary in size from a pea to a large marble

Pubic Crest

Located directly inferior to the navel and superior to the genitals. Formed by the superior, medial edge of both pubic bones, the horizontal crest is roughly 2 inches wide and clearly palpable. Attachment Site: Rectus Abdominis Muscle Abdominal Aponeurosis

Greater Trochanter of the Femur

Located distal to the iliac crest, this large, superficial mass is on the side of the hip. Easily palpable. Attachment site: Gluteus Medius Gluteus Minimus Lateral Rotators of the hips

Median Sacral Crest

Located in the center of the sacrum and is composed of 3-4 points. On either side of the Median Sacral is the Lateral Sacral Crest - a small series of bony knobs.

Anterior Inferior Iliac Spine (AIIS)

Located inferior and medial to the Anterior Superior Iliac Spine (ASIS).It's smaller and flatter than the ASIS, but it's also deep to the Sartorius Muscle and Inguinal Ligament. Attachment Site: Rectus Femoris Muscle

Anterior Superior Iliac Spine (ASIS)

Located on the anterior and superior aspect of the ilium (hip bone). Superficial tips located below waistline. Attachment Site: Sartorius Muscle Inguinal Ligament

Iliac Fossa

Located on the medial surface of the ilium, it's part of the bone that's a bowl-shaped.

Pubic Crest and Tubercles

Located on the superior aspect of the pubic crest Each tubercle is shaped like a small horn The tubercles might be 1-2 inches apart and not always easy to palpate. Attachment Sites: Adductor Longus Muscle Inguinal Ligament

Umbilicus

The "Navel" is located at the midline of the body, it is superior to the level of the ASIS.

Coccyx

The "tailbone" is located at the top of the gluteal cleft and attaches to the end of the sacrum. Composed of 3-4 fused bones, it has a segmented, bumpy contour and cam be an inch or more in length. Its tip may curve in toward the body or veer slightly to the left or right.

Sacroiliac Joint

The junction that's between the sacrum and the ilium. It's located medial to the PSIS and is deep to the Thoracolumbar Aponeurosis and Posterior Sacroiliac Ligaments. The Ilium overhangs the sacroiliac joint.

Iliac Crest

The long, superior edge of the the ilium. Begins in the ASIS and extends around the side of the torso to the end at the Posterior Superior Iliac Spine (PSIS). The crests are superficial and easily palpable as the the muscles that attach to it do not cross ever its edge.