Lecture 1 -- Functional Anatomy of Pelvic Girdle and Hip Joint

How does the hindlimb form embryologically?

1. Toes rotate cranially

2. Stifle joint rotate cranially

3. Tibia and fibula don’t rotate → Remain parallel

→ Flexor and extensor angles different to forelimb

Name the bones that form pelvic girdle

1. Ilium

2. Ischium

3. Pubis

4. Acetabulum

How does the hindlimb form embryologically?

1. Toes rotate cranially

2. Stifle joint rotate cranially

3. Tibia and fibula don’t rotate → Remain parallel

→ Flexor and extensor angles different to forelimb

Name the bones that form pelvic girdle

1. Ilium

2. Ischium

3. Pubis

4. Acetabulum

Name the key structure of hip bone

Name the key structure of pelvic bone

What type of bone is the pelvis, and what are the key structures of this type of bone?

Flat bone.

No medullary cavity

Where can bone marrow be harvested from the pelvis?

Wing of the ilium.

What is the tuber sacrale formed by?

Cranial dorsal iliac spine and Caudal dorsal iliac spine.

How many sacral vertebrae are fused to form the sacrum in dogs?

3

What are the ligaments found in the sacroiliac joint?

1. Dorsal sacroiliac ligament

2. Ventral sacroiliac ligament

Where does the sacrotuberous ligament attach?

Extends from the last sacral and first coccyx vertebrae to ischiatic tuberosity

What is the function of the sacrotuberous ligament?

Allow partial attachment of some muscle e.g. gluteal muscle and biceps femoris

Which ligament cannot be found in cat?

Sacrotuberous ligament

What is the iliopubic eminence?

It is the point where the ilium meets the pubis.

What are the functions of ischiatic arch?

Allow muscle attachment for reproductive organs

What is the pecten?

Concavity at cranial aspect of the pelvic floor

What fills the pecten area?

Prepubic tendon

Where do the two hip bones join together?

Pelvic symphysis

Name the key structure of acetabulum

What is the obturator foramen bounded by?

Pubis and ischium.

What fills the acetabular notch?

Transverse ligament.

Which ligament attaches to the acetabular fossa and the head of the femur?

Round/ teres ligament/ Ligament of head of femur

What passes through obturator foramen?

Obturator nerve

Which muscles attach to the obturator foramen externally and internally?

Internal obturator muscle; External obturator muscle

How does the obturator foramen differ between dogs and cats on a radiograph?

Dog: Round and circular obturator foramen

Cats: Oval and larger obturator foramen

How does the orientation of the wings of the ilium and ischium differ between dogs and cats on a radiograph?

Dog: Wings of ilium and ischium diverge

Cats: Wings of ilium and ischium parallel

What are the main ossification centre of pelvic bone?

Ilium, ischium, pubis and acetabular bone x1

What are the secondary ossification centre of pelvic bone?

Dorsal iliac crest, Tuber ischium and ischiatic arch

Describe the key structure of femur

Which part of the femur does the round ligament attach to in the acetabular fossa?

Fovea of femur

On which aspect is the greater trochanter located?

Lateral aspect of the femur

On which aspect is the lesser trochanter located?

Medial aspect of the femur

How many centres of ossification of femur? What are they?

4

Head

Greater trochanter

Body

Distal epiphysis

What are the special features of the sesamoid bones in cat?

Patella always present

BUT medial fabella often not ossified → Not visible on radiographs

What is the difference between lateral and medial trochlear ridge?

Lateral trochlear ridge is thicker than medial trochlear ridge

Where is the extensor fossa located? Is it on the medial or lateral aspect? What is it for?

Lateral aspect

Tendon of origin of long digital extensor muscle