What are the main anatomical components of the pelvic region?
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Divided into Internal Structures and External Structures.
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What are the main anatomical components of the pelvic region?
Divided into Internal Structures and External Structures.
What type of bone is the innominate bone classified as?
An irregular bone.
What types of viscera does the pelvis house and protect?
Pelvic viscera proper and viscera of the abdomen (greater pelvic portion).
What structures make up the pelvic floor?
Muscular system and ligaments.
What portion of the acetabulum does the Pubis form?
1/5th of the acetabulum (anterior portion).
What is the function of the anterior longitudinal ligament of the vertebral column in the pelvis?
It stabilizes the central part of the pelvis.
What happens to the sacroiliac joint during pregnancy?
It loosens to allow for widening of the birth canal.
What is the sacral promontory?
The inwardly projecting anterior part of the body of the first sacral vertebra.
What role does the pelvis play in locomotion?
It acts as a site of attachment for the lower limbs to the axial skeleton and for muscles and ligaments used in locomotion.
What is one of the primary functions of the pelvis related to reproduction?
It is the site for pregnancy.
What portion of the acetabulum does the Ischium form?
2/5th of the acetabulum (posterior portion).
What viscera can be seen when looking down into the pelvic region?
Lower end of GIT (caecum, sigmoid colon, rectum), uterus, fallopian tubes, ovaries, ureter, and urinary bladder.
What are the anatomical boundaries of the pelvis?
Pelvic Brim (Pelvic Inlet) and Pelvic Outlet.
What does the Lesser pelvis contain?
The pelvic cavity and pelvic viscera (bladder, rectum, pelvic genital organs, and terminal part of the urethra).
What is the Lumbo-sacral Joint?
The articulation between the bottom of the lumbar spine (L5 vertebra) and the top of the sacrum (S1).
What artery is given rise to by the hip and back region?
The superior gluteal artery.
What is the anterior superior iliac spine used for?
It is a site for attachment of the inguinal ligament and used in the measurement of limb length.
What does the greater trochanter indicate?
It gives an idea of where the hip joint lies.
What is the significance of the ischial tuberosities?
They provide the human seat, as we sit on them.
What lies underneath the pelvic diaphragm?
The perineum.
At what level does the common iliac artery divide into internal and external iliac arteries?
At the level of the pelvic brim (L5/S1).
What shape is the pelvic outlet?
Diamond shaped.
Where does the greater pelvis lie in relation to the pelvic brim?
Above the pelvic brim.
What is located under the pelvic brim?
The true pelvic cavity, which ends at the pelvic diaphragm.
What is present before the ossification of the innominate bones?
Tri-radiate cartilage.
What stabilizes the Sacro-iliac Joint?
The presence of ligaments and the handshake formation of the articular surfaces.
What is a clinical significance of the supracristal plane?
It is a site for lumbar puncture.
What shape is the pelvic cavity?
Spherical.
How does the hip joint compare to the shoulder joint in terms of stability?
The hip joint is more stable.
What is the role of the tri-radiate cartilage?
It joins the three bones of the innominate bone.
What portion of the acetabulum does the Ilium form?
2/5th of the acetabulum (superior portion).
What forms the pelvic brim (linear terminalis)?
The joining of the margin of ala, the arcuate line, the sacral promontory, the pubic crest, and pecten pubis.
What are the three main types of bones that form the bony pelvis?
Two pelvic bones (left and right), one sacrum, and one coccyx.
What do the sacrospinous and sacrotuberous ligaments create?
The greater and lesser sciatic foramina, respectively.
What does the external iliac artery become after passing under the inguinal ligament?
The femoral artery.
What structure do the three bones of the innominate bone form?
The acetabulum.
What is the location of the Greater pelvis?
Above the pelvic brim.
Where is the Lesser pelvis located?
Below the pelvic brim and ends at the pelvic diaphragm.
What is the process called when the innominate bones ossify?
Tri-radiate ossification.
Where are the intervertebral foramen located on the sacrum?
On the anterior/posterior surface.
What does the internal iliac artery divide into?
Anterior and posterior trunks.
What are the similarities between the pelvis and scapula?
Both serve as attachment points for limbs, but their functions differ.
What forms the lowermost aspect of the vertebral column?
The sacrum.
How many sacral bones fuse to form the sacrum?
5 sacral bones (S1 to S5 vertebrae).
What is the interaction between the pelvic floor and which systems?
The urinary tract and reproductive tract.
What is the pelvic inlet?
The junction between the greater and lesser pelvis.
What type of joint is the Sacro-iliac Joint?
A synovial joint.
What is the pelvic outlet?
Located between the end of the lesser pelvis and the beginning of the pelvic wall.
What role does the hormone Relaxin play during pregnancy?
It acts to loosen the Pubic Symphysis to allow for widening of the birth canal.
What shape is the pelvic brim?
Heart shaped.
What are the internal structures of the pelvic region responsible for?
The Urinary System, Lower Gastro-intestinal Tract, Reproductive System, Parturition, Pelvic Floor, and Lining of the cavity (peritoneum).
How does the pelvis support the body in an upright posture?
It helps carry the weight of the head, neck, thorax, upper limbs, and trunk.
What does the Greater pelvis support?
The lower abdominal viscera (ileum and sigmoid colon).
What forms the middle of the posterior border of the bony pelvis?
The sacrum and coccyx.
What is the significance of the rectovesical pouch in males?
It is a pouch located between the rectum and the bladder.
What artery does the anterior trunk of the internal iliac artery give rise to?
The obturator artery.
What is the pubic crest used for?
It is a site for suprapubic puncture of the urinary bladder.
What three bones compose the innominate bone?
Ilium, Ischium, and Pubis.
What curvature does the sacrum form in the vertebral column?
The sacral primary curvature.
What are the posterior borders of the pelvic inlet?
Sacral promontory and sacral wings.
How many coccygeal bones typically compose the coccyx?
4 coccygeal bones (though variable from 3 to 5).
What is the coccyx analogous to in other animals?
The tail.
What is the Pubic Symphysis?
A secondary cartilaginous joint made of a fibrocartilaginous disc between the articular surfaces of the pubic bones.
How does the shoulder girdle compare to the pelvic girdle in terms of mobility?
The shoulder girdle is more mobile, allowing for a greater range of movement.
What is the sacroiliac joint?
The articulation between the sacrum and the ilium.
What does the anterior sacral-iliac ligament reinforce?
The sacro-iliac joint.
How do the sacrotuberous and sacrospinous ligaments assist during childbirth?
They can stretch under the influence of progesterone, increasing the size of the pelvic outlet.
What is the role of ligaments in preventing upward tilting of the sacrum?
They anchor the sacrum down to the bony structures of the pelvis.
What are some medical complaints associated with the pelvic region?
Pelvic Inflammatory Disease, Urinary Tract Infections, Infertility, Complications in Childbirth, Episiotomies & Infections of Soft Tissues, Urinary Incontinence, Faecal Incontinence, Disorders of the lower gastrointestinal tract, Diseases of the lower gastrointestinal tract, Straddle Injuries.
What are some external structures of the pelvic region?
Musculature for upright posture, musculature for the proximal lower limb, and gonads of the male.
What is the outer bony edge of the pelvic inlet called?
The pelvic brim.
What forms the anterior border of the pelvic inlet?
Pubic symphysis.
What is the strongest ligament in the Sacro-iliac Joint?
The interosseous sacroiliac ligament.
How does the Sacro-iliac Joint change during pregnancy?
It loosens to allow for widening of the birth canal.
What is the Hip Joint?
The articulation between the acetabulum and the head of the femur.
What is the supracristal plane?
A horizontal line that joins the left and right iliac crest, indicative of vertebral level L4/L5 intervertebral disc.
At what point does the pelvic region begin?
At the bifurcation of the descending aorta (L4/L5) into the right and left common iliac artery.
What are the differences in the manner of attachments between the upper and lower limbs?
The shoulder girdle allows for more mobility, while the pelvic girdle provides stability.
At what age do the bones of the innominate bone completely ossify?
Between ages 18 to 25.
What do the pelvic bones and sacrum/coccyx together form?
The pelvic ring.
What are the borders of the pelvic outlet?
Posterior: Tip of the coccyx; Lateral: Ischial tuberosity, sacro-tuberous ligament & ischiopubic ramus; Anterior: Pubic arch.
What is another name for the lesser or true pelvis in females?
Gynecological pelvis.
What is the role of ligaments like the cardinal ligament and rectouterine ligament?
They play a major role in the maintenance of the pelvic floor.
What happens to the Sacro-iliac Joint with age?
It becomes fibrous and eventually completely ossifies.
What does the anterior trunk of the internal iliac artery supply?
Arterial blood to organs of the true pelvis.
What does the coccyx represent in apes?
The final segment of the vertebral column.
