Hip

Question 1

What are the causes of hip dysplasia?

Answer 1

= laxity and instability of the hip joint
- large breed dogs
Congenital, nutritional, body weight, growth rate

Question 2

What is the clinical presentation of hip dysplasia?

Answer 2

1. Immature dogs
   Subluxation of the femoral head
   Effusion of the hip joint
   Subside at 12-18 moths
2. Adult dogs - present with OA

Question 3

What is the presentation in immature dogs?

Answer 3

Less than 1 year old 
Unilateral / bilateral hindlimb lameness 
Bunny hopping gait 
Reluctance to exercise
Pain upon hip flexion
Positive ortolani test

Question 4

What is the clinical presentation of hip dysplasia in adult dogs?

Answer 4

Mature dogs
Stiffness after rest / exercise 
Bunny hopping
Usually bilateral 
Pain upon joint manipulation 
Reduced ROM
Palpate the spine to differentiate from lumbosacral disease

Question 5

What are the primary radiographic changes seen on VD radiographs in hip dysplasia?

Answer 5

Wide joint space with medial divergence of cranial joint space
Centre of the femoral head lies outside the acetabular edge
Coxa valga >150 degree angle of femoral shaft to neck

Question 6

What are the secondary changes seen in hip dysplasia when there is osteoarthritis due to hip dysplasia?

Answer 6

New bone formation at the femoral head = Morgan line
Remodelling / thickening of the femoral head / neck
Remodelling of the cranial effective acetabular rim
Acetabulum is flattened

Question 7

How should you conservatively manage hip dysplasia in a young dog?

Answer 7

Rule out concurrent stifle disease
Rest - only 5-10 minute walks per day on a lead
NSAIDS and paracetamol
Gabapentin if you suspect neuropathic pain
Weight loss

80% success rate

Question 8

What is a triple pelvic osteotomy?

Answer 8

Triple pelvic osteotomy

• 3 osteotomies, acetabulum rotated and stabilised with a slocum plate
• increases the cover of the femoral head

90% success rate
Only indicated in immature dogs with no secondary radiologic changes

Question 9

What are the surgical treatment options for immature dogs with hip dysplasia?

Answer 9

Triple pelvic osteotomy
Femoral head and neck excision
Total hip replacement
Juvenile symphydesis

Question 10

When can a hip replacement be placed in an immature dog?

Answer 10

From 12 months old
Indicated in very severe cases
Keep pain free until a hip replacement can be performed

Question 11

What is a juvenile symphydesis and when can it be performed?

Answer 11

Less than 6 months old

Uses diathermy to arrest the growth of the pubic symphysis

Question 12

How can hip dysplasia in a mature dog be managed?

Answer 12

Conservative treatment - pain relief and other treatments for OA

Surgical treatment

• for cases that aren’t responsive to conservative management
• total hip replacement

Question 13

When is a femoral head and neck excision indicated?

Answer 13

Only recommended in dogs under 15 kg
Salvage procedure - femoral head and neck removed
A false hip joint will be formed

Indicated in:
Hip dysplasia in mature small dogs that has failed to respond to conservative management
Legg calve perthes
Unreducible fractures

Question 14

When is a total hip replacement recommended in mature dog with hip dysplasia?

Answer 14

Over 15kg

Dogs that have failed to response to surgical management

Question 15

When is a total hip replacement contraindicated?

Answer 15

Previous hip surgery
Chronic systemic illness - skin problems
Too small for implants

Question 16

What is the common clinical presentation of legg calve perthes?

Answer 16

WHWT, poodles and terriers
- ischaemic necrosis of the femoral head
Onset at 5 months 
Unilateral lameness
Pain on palpation and manipulation  of the hip 
Crepitus in the hip

Question 17

What radiographic changes will you see with legg calve perthes disease?

Answer 17

Remodelling around the femoral head
Loss of mineral density of the femoral head
Collapse of the articular cartilage

Question 18

How can you treat legg calve perthes?

Answer 18

Surgical management

• FHNE
• THR

Question 19

Where are the most locations of fractures of the femoral head and neck?

Answer 19

Capital and capital physeal - femoral head
Femoral neck
Greater trochanter

Question 20

What is a typical clinical presentation of a capital physeal fracture?

Answer 20

Immature animals - 4-7 months old cats
Following trauma eg RTA
Pain upon hip manipulation

Dx: radiography

Question 21

How should you treat capital physeal fractures?

Answer 21

3 diverging or parallel Kirschner (K) wires

Or Arthrodesis wires

Question 22

How does a coxofemoral joint luxation usually present?

Answer 22

Young dog - less than 12mo
Following minor trauma eg RTA
Leg carried in flexion - stifle out, hock in
Decreased distance between the greater trochanter of the femurs and the wing of the illum on the luxated side when palpating the pelvis

Question 23

How can you attempt closed reduction of a coxofemoral luxation?

Answer 23

Within 48 hours of injury
Out under GA and tie dog to table
Pull the leg in the opposite direction lot the way it came out and rotate back into place

If re-luxation occurs - open, reduce and stabilise

Place an Ehmer sling and cage rest for 7-10 days

Question 24

How can you perform an open reduction on a coxofemoral subluxation?

Answer 24

Craniolateral approach to the hip
Remove haematoma and bone fragments from the acetabulum and lavage 
Replace the femoral head with caudal traction
Suture the joint capsule back together 
Or apply:
- toggle fixation
- trans-articular pin
- iliofemoral suture