Description The pubic bone is the anterior portion of the hip bone, forming the front part of the pelvis. The pubic bones meet in the front and center of the pelvis at a joint called the pubic symphysis

Functions: The pubic bones help to support the pelvis and connect the upper and lower body. They also form part of the acetabulum, the hip socket

Description It a paired bone located at the lower and posterior part of the pelvis. It forms the hip bone, along with the ilium and pubis. The ischium contributes to the acetabulum, a socket that articulates with the femur to form the hip joint

Functions:

Weight Bearing: The ischial tuberosities bear the weight of the body when sitting

Hip Joint Formation: The ischium, along with the ilium and pubis, contributes to the formation of the acetabulum, a crucial part of the hip joint

Muscle Attachment: The ischium serves as an attachment point for several muscles, including the hamstrings, adductor magnus, and inferior gemellus

Ligament Attachment: The ischium also provides attachment points for ligaments, such as the sacrospinous and sacrotuberous ligaments

Pelvic Support: As part of the pelvis, the ischium helps support the upper body's weight and balance

Description It is a prominent bony ridge located at the top of the ilium, a major part of the hip bone. It forms the upper border of the ilium and extends from the anterior superior iliac spine to the posterior superior iliac spine

Functions: It provides attachment points for various muscles and ligaments, including the gluteus maximus, iliacus, and transversus abdominis

Description It is a prominent, roughened area on the ischium, a bone in the pelvis

Functions: It serves as an attachment point for several muscles, including the hamstrings (semitendinosus, semimembranosus, and long head of biceps femoris)

Description It is the widest and largest of the three parts of the hip bone, and is located superiorly. A flared expanded upper part forming the iliac crests, the iliac spines, and a small inferior part forming two-fifths of the acetabulumThe body of the ilium forms the superior part of the acetabulum

Functions:

Weight Bearing: The ilium is a major weight-bearing bone, helping to transmit the weight of the upper body to the lower limbs

Muscle Attachment: The ilium provides numerous attachment points for muscles of the trunk and lower limbs, enabling movement and stability.

Hip Joint Stability: The ilium, along with the ischium and pubis, contributes to the stability and function of the hip joint

Protection of Pelvic Organs: The ilium, along with other pelvic bones, protects the bladder, rectum, and, in females, the uterus and ovaries

Sacroiliac Joint Movement: The sacroiliac joint allows for some movement of the pelvis, including nutation and counternutation, which can affect posture and mobility

Description It is a cup-shaped socket on the lateral surface of the hip bone, formed by the fusion of the ilium, ischium, and pubis. It articulates with the femoral head to form the hip joint, allowing for a wide range of motion

Functions:

The acetabulum forms a ball-and-socket joint with the femoral head, enabling a wide range of hip movements

It supports the weight of the body through the hip joint, contributing to overall stability

The acetabular labrum helps to increase the stability of the hip joint and limits the range of motion

Description It is a triangular, shield-shaped bone located at the base of the spine, formed by the fusion of five sacral vertebrae (S1-S5)

Functions:

Weight Transfer: The sacrum acts as a bridge, transferring the weight of the upper body from the spine to the pelvis and lower limbs

Muscular Attachment: The sacrum serves as an attachment point for numerous muscles, including the piriformis, gluteus maximus, and erector spinae, contributing to movement and posture

Protection: The sacrum protects the spinal cord, nerves, and pelvic organs from injury

Support: The sacrum provides a strong base for the spine, enabling upright posture and movement

Pelvic Stability: The sacroiliac joints, formed by the articulation of the sacrum with the iliac bones, provide stability to the lower back and pelvis

Description Also known as tailbone, is the terminal portion of the vertebral column, located at the bottom of the spine. It's typically formed by the fusion of three to five rudimentary vertebrae. The coccyx articulates with the sacrum at the sacrococcygeal joint

Functions:

Pelvic Floor Support: The coccyx helps support the pelvic floor, which plays a role in maintaining fecal continence and supporting pelvic organs

Seated Weight Support: The coccyx, along with the ischial tuberosities (sitting bones), forms a tripod-like structure that helps distribute body weight and provide stability while sitting

Attachment Point: As a site of attachment for muscles and ligaments, the coccyx plays a role in the movement and function of the pelvic floor

Anus Support: The coccyx helps to maintain the position of the anus

Sacrococcygeal Joint: The coccyx articulates with the sacrum at the sacrococcygeal joint, which allows for limited movement, contributing to spinal flexibility during activities like sitting and childbirth

Description It is the lowest vertebra in the lumbar region of the spine and is the largest of the five lumbar vertebrae

Functions: It plays a crucial role in supporting the body's weight, providing flexibility, and transmitting signals to the lower extremities. It also contributes to shock absorption and spinal stability

Description It is a thick band of fibrous tissue that extends along the front surfaces of the vertebral bodies, starting from the anterior tubercle of the atlas and continuing down the entire length of the spine to the sacrum

Functions: It plays a crucial role in the biomechanics of the spine, helping to protect it from injury and maintain its proper function such as maintaining spinal stability by limiting excessive extension and supporting the anterior aspect of the vertebral column

DescriptionIt is a fibrous sheet that almost completely closes the obturator foramen, an opening in the pelvis formed by the pubic and ischial bones

Functions:

Closure: It almost completely closes the obturator foramen, serving as a structural component of the pelvic floor

Passage: The obturator canal, formed by the superior margin of the membrane and the pubic bone, allows the obturator nerve, artery, and vein to pass through

Muscle Attachment: It provides a surface for the attachment of the obturator internus and externus muscles, which are involved in hip rotation and stability

Description It is a strong band of connective tissue that connects the lumbar spine (specifically the transverse processes of L4 and L5) to the iliac bone (specifically the iliac crest)

Functions: It helps stabilize the lumbosacral spine and sacroiliac joint, restricting movement and supporting the lower lumbar spine

Description is a triangular, pelvic ligament that connects the ischial spine (on the pelvis) to the sacrum and coccyx

Functions:

Stabilization: It helps stabilize the sacroiliac joint, which connects the pelvis to the vertebral column

Nutational Resistance: It helps resist the movement of the sacrum during weight-bearing and gait

Description It is a significant anatomical landmark on the inner surface of the abdominal wall, specifically within the rectus sheath

Functions: It marks the point where the posterior sheath (formed by the internal oblique and transversus abdominis muscles) transitions into the transversalis fascia

Description It is a thickened, inferior part of the external oblique aponeurosis, a strong sheet of connective tissue

Functions: It forms the inferior wall of the inguinal canal, a passage through which nerves, blood vessels, and, in males, the spermatic cord pass

Description It is a thickened band of fascia that originates from the iliac crest and extends downward and medially, attaching to the iliopectineal eminence of the hip bone

Functions: It acts as a septum, dividing the space deep to the inguinal ligament into two compartments:

Muscular Lacuna: Contains the iliopsoas muscle and the femoral nerve

Vascular Lacuna: Contains the femoral artery, vein, and other vessels

Description It connects the posterior superior iliac spine and the iliac crest to the sacrum. It has two components: a long part and a short part. The long part extends from the PSIS to the lateral crest of the third and fourth sacral segments, and can be palpated just below the posterior superior iliac spine. The short part is more superior and runs between the first and second transverse tubercles of the sacrum and the iliac tuberosity

Functions:

Pelvic Stability: The ligaments play a key role in stabilizing the sacroiliac joint and resisting various movements, including nutation and counternutation

Load Transmission: The ligaments help to transfer forces between the spine and lower extremities

Sensory Input: The ligaments contain nerve fibers that can detect pain and provide information about joint position and movement

Description It is a strong, fibrous cord that connects the tips of the spinous processes of the vertebrae, from the seventh cervical vertebra (C7) down to the third or fourth lumbar vertebrae (L3/L4)

Functions: Provides stability and support to the spine, helping to resist hyperextension and flexion

Description It is a strong, fan-shaped ligament located in the posterior pelvis that connects the sacrum and coccyx to the ischial tuberosity

Functions:

Sacroiliac Joint Stabilization: The STL is a primary stabilizer of the SIJ, helping to restrict excessive movement and maintain stability

Force Transmission: It transmits forces between the vertebral column, pelvis, and lower limbs

Kinetic Chain Connection: The STL and the sacroiliac joint are part of a kinematic chain, influencing movement and stability in the lower back and pelvis

Description It is a thick fibrous band that connects the superior margins of the pubic symphysis, the joint between the two pubic bones

Functions: It helps to stabilize the pubic symphysis, along with other ligaments like the inferior (arcuate) pubic ligament

Description It is a thick triangular arch of ligamentous fibers that connects the two pubic bones at the lower portion of the pubic symphysis

Functions: It helps to stabilize the pubic symphysis, preventing excessive movement or separation of the joint