Abdominopelvic Pelvic Bones and Joints Lecture Objectives

What are the boundaries of the abdominal cavity

Cranial: Diaphragm

Caudal: pelvic inlet

Dorsal Margin: lumbar vertebrae/sublumbar muscles

Lateral and ventral margins: abdominal wall muscles

What are the pelvic cavity boundaries

Cranial: pelvic inlet

Caudal: pelvic outlet

Dorsal: sacrum and coccygeal vertebrae

Lateral and Ventral: pelvis and pelvic diaphragm

What are the abdominopelvic boundaries

Peritoneum

Bones of the pelvis

Ilium Ischium and pubis

Pelvis is split left and right into two Os coxae that join at the pelvic symphysis, creating the pelvis/Ossa coxarum

(Acetabular bones in young animal, fuses by)

Ishiatic vs sciatic

They are synonyms

What are the the centers of ossification in the pelvis

Ilium, ischium, pubis, acetabular bone, iliac crest, ishiatic tuberosity

When do the centers of ossification fuse in small animals

6 months

What are the bony comments of the sacroiliac joint

Auricular surface of ilium and auricular surface of sacrum.

What ligaments reinforce the sacroiliac joint

Ventral and dorsal sacroiliac ligament (between sacrum and ilium)

Supraspinous ligament (connects adjacent spinous processes and vertebrae)

Interarcuate ligament (connects adjacent vertebral arches)

NOT IN CATS: Sacrotuberous ligament (connects ischiatic tuberosity and S3-Cd1)

What are the bony components of the pelvic symphysis

Left and right os coxae

Is made of the pubic symphysis and ishcial symphysis

What type of of joint is the pelvic symphysis

Cartilaginous

What are the components of the coxofemoral joint (hip)

acetabulum, acetabular fossa, acetabular notch, acetabular labrum, transverse acetabular ligament, head of the femur, ligament of the head of the femur

What type of joint is the coxofemoral joint?

Ball and socket

Synovial joint

What is hip dysplasia

Abnormal joint that causes laxity of the coxofemoral joint

What can cause hip dysplasia

Most often a shallow acetabular fossa

What are radiographic signs of hip dysplasia

*Suboptimal femoral head coverage (<50%)

*Flattened femoral head

*Thickened femoral neck

Caudal curvilinear femoral neck osteophytes (Morgan’s line) can predict FUTURE hip dysplasia

Increased joint space

Osteoarthritis changes

List the features of the ilium

Tuber coxae, auricular surface arcuate lines

List the features of the ischium

Ischiatic tuberosity, ishiatic spine, ishiatic arch,

List the features of the pubis

Pectin

List the features of the sacrum

Auricular surface, promontory

What muscles attach to the Tuber coxae

External and internal abdominal oblique muscles, trans versus abdominis muscle

What muscles attach to the ishiatic tuberosity

Ishiocavernosus muscle

What muscles attach to the ishiatic spine

Coccygeus

What muscles attach to the pecten

Abdominal muscles via prepubic tendon

What attaches at the ishiatic tuberosity other than muscles?

sacrotuberous ligament

Crus penis or clitoris