Osteology and Arthrology of the Pelvis: The Hip Bone

Vocabulary practice flashcards covering the anatomical features, borders, surfaces, landmarks, and arthrology of the hip bone (os coxae) and pelvic girdle.

Pelvic Girdle (Pelvis)

An anatomical structure formed by the sacro-coccygeal portion of the vertebral column, the hip bones, and the joints and ligaments uniting them; essential for understanding the mechanism of childbirth.

Hip Bone (Os Coxae)

A broad, irregularly quadrilateral bone possessing two surfaces, four borders, and four angles, formed by the fusion of three parts: the ilium, ischium, and pubis.

Acetabulum

A thick articular cavity situated in the middle portion of the lateral surface of the hip bone that articulates with the head of the femur.

Ilium

The broad, flattened superior segment of the hip bone located superiorly to the acetabulum, consisting of a body and a wing.

Pubis

The anterior portion of the inferior hip bone, located anterior to the obturator foramen, comprising a body, a superior pubic ramus, and an inferior pubic ramus.

Ischium

The posterior portion of the inferior hip bone, located posterior to the obturator foramen, composed of an ischial body and an ischial ramus.

Ischiopubic Ramus

The continuous bony bar formed by the union of the ischial ramus and the inferior pubic ramus.

Acetabular Limbus (Rim)

The elevated border surrounding the acetabulum, interrupted by three notches corresponding to the junction points of the ilium, ischium, and pubis.

Acetabular Notches

The three interruptions of the acetabular rim: the anterior iliopubic notch, the posterior ilioischial notch, and the inferior acetabular notch.

Acetabular Notch

The widest and deepest notch of the acetabular rim, located inferiorly between the ischium and the pubis, bounded by the two extremities of the lunate surface.

Acetabular Fossa

The non-articular, quadrilateral central depression forming the floor of the acetabulum.

Lunate Surface

The peripheral, crescent-shaped articular portion of the acetabulum whose two extremities bound the acetabular notch.

Gluteal Surface

The broad lateral surface of the ilium located superior to the acetabulum, divided into three muscular zones by the anterior and posterior gluteal lines.

Gluteal Lines

Ridges on the gluteal surface: the anterior, posterior, and inferior gluteal lines, which divide the surface into zones for the insertion of the gluteus minimus, gluteus medius, and gluteus maximus.

Obturator Foramen

A large opening situated inferior to the acetabulum, bounded superiorly by the acetabulum, anteriorly by the pubis, and posteriorly by the ischium, closed in life by the obturator membrane.

Obturator Groove

A channel formed by the divergence of the two margins of the obturator foramen superiorly, through which the obturator nerve and vessels pass.

Innominate Line (Arcuate Line)

An antero-inferiorly directed ridge on the medial surface of the hip bone that demarcates the boundary between the greater pelvis and the lesser pelvis.

Iliac Fossa

A wide concavity situated superolaterally to the innominate line on the medial surface of the hip bone, serving as the site of insertion for the iliacus muscle.

Auricular Surface of the Hip Bone

An ear-shaped articular surface on the medial aspect of the ilium, located postero-inferiorly to the innominate line, which articulates with the sacrum.

Anterior Superior Iliac Spine (ASIS)

The uppermost projection of the anterior border of the hip bone, giving insertion to the sartorius muscle and the tensor fasciae latae.

Anterior Inferior Iliac Spine (AIIS)

A bony projection on the anterior border, situated below the innominate notch, serving as the insertion point for the direct tendon of the rectus femoris muscle.

Pectineal Surface

A surface on the anterior border of the hip bone where the pectineus muscle inserts, bounded posteriorly by the pectineal line and terminating medially at the pubic tubercle.

Greater Sciatic Notch

A large notch on the posterior border of the hip bone, inferior to the posterior inferior iliac spine, traversed by the piriformis muscle, nerves, and blood vessels.

Ischial Spine

A pointed bony prominence along the posterior border separating the greater and lesser sciatic notches, serving as the insertion site for the sacrospinous ligament.

Lesser Sciatic Notch

A notch on the posterior border located inferior to the ischial spine, traversed by the obturator internus muscle, blood vessels, and nerves.

Iliac Crest

The italic S-shaped superior border of the hip bone that gives insertion to the broad abdominal muscles and features an external lip, internal lip, and intermediate line.

Symphyseal Surface

An articular facet on the superior aspect of the inferior border of the hip bone that articulates with the contralateral facet to form the pubic symphysis.

Ischial Tuberosity

A voluminous, heavy bony projection forming the postero-inferior angle of the hip bone, serving as the attachment site for multiple muscles.

Sacroiliac Articular Cartilage Layers

The two protective cartilage layers covering the auricular articular surfaces: a deep layer of hyaline cartilage and a superficial layer of fibrocartilage.

Sacroiliac Means of Union

The stabilizing structures of the sacroiliac joint, including an articular capsule, intrinsic ligaments (anterior, posterior, and interosseous sacroiliac ligaments), and an extrinsic ligament (iliolumbar ligament).

Anterior Sacroiliac Ligament

An intrinsic ligament that attaches medially to the base and anterior surface of the sacrum, lateral to the first two anterior sacral foramina, and extends laterally toward the hip bone.