Hindlimb Lameness- Hip & Hock

Question 1

What predisposes an animal to Hip Dysplasia?

Answer 1

Genetic- polygenetic disease
also environmental influence such as diet, exercise

Question 2

What is the pathophysiological process of Hip Dysplasia?

Answer 2

Hip joint has increased laxity- so hip starts to move away from the femoral head due to this excess flexibility

Question 3

What other pathologies can Hip Dysplasia lead to? (2)

Answer 3

Acetabular rim microfractures
OSTEOARTHRITIS

Question 4

At what age does Hip Dysplasia usually present?

Answer 4

6-7 months old

Question 5

What are the most common clinical signs of Hip Dysplasia? (5)

Answer 5

Bunny hopping
Hindlimb lameness
Exercise Intolerance
Lateral pelvic swaying- animal tries to avoid using the hips
Possible muscle atrophy

Question 6

In older dogs with suspected Hip Dysplasia, what other diagnosis must we eliminate first?

Answer 6

Cruciate Ruptures- check cranial drawer test

Question 7

How do we confirm Hip Dysplasia with radiographs?

Answer 7

Extended leg radiograph and one of the lateral pelvis is taken
Look for the acetabulum to cover 50% of the femoral head

Question 8

What are Luxoid hips?

Answer 8

Most severe form of Hip Dysplasia- when the femur appears ‘floating away’ from the pelvis

Question 9

In older dogs, what may we also see on Radiographs that indicate long term Hip Dysplasia? (4)

Answer 9

Thickening and capsule mineralisation
Osteophytes/ new bone formation (ragged femoral head)
Flattening of the femoral head
Flattening of the acetabulum

Question 10

What two tests can we perform on immature dogs to test Hip laxity?

Answer 10

Bardens test- attempt to luxate the head of the femur laterally out of the acetabulum- more than 0.5cm movement is abnormal
Ortolani Test- push down on hip and abduct it- if it pops then = hip dysplasia

Question 11

What Norberg angle is indicative of Hip dysplasia?

Answer 11

More than 105 degrees (line between middle of the femoral head and edge of acetabulum)

Question 12

What is the prognosis of dogs with Hip dysplasia without surgical management?

Answer 12

70% functionally doing well after 12-15 months as the joints eventually stabilise by fibrosis

Question 13

What conservative management is recommended for dogs with Hip Dysplasia?

Answer 13

1. Exercise Adjustment- regular, short term exercise
2. Physical Therapies e.g. hydrotherapy & physiotherapy
3. Diet- keep lean and give joint supplements that are high in omega 3 fatty acid
4. NSAIDs for 4-6 weeks

Question 14

What are the aims of a Pelvic Osteotomy?

Answer 14

Cut pelvic bone to allow rotation of the acetabulum to increase dorsal coverage and then stabilise with plate and screws

Question 15

What does a juvenile pubic symphysodesis achieve?
But when is it contraindicated?

Answer 15

Damages the growth plate to rotate the acetabulum
Cannot be done to breeding dogs- hips too narrow for natural births

Question 16

Which surgical treatment generally has the best prognosis for working dogs?

Answer 16

Arthroplasty- with Total Hip Replacement which then allows pseudoarthrosis (‘metal hip’ fuses with bone)

Question 17

What is the better alternative to owners who cannot afford a total hip replacement?
What does it require for a good prognosis?

Answer 17

Femoral Head & Neck Excision- but it does require aggressive rehabilitation

Question 18

How does the BVA-KC screening for Hip Dysplasia work?

Answer 18

When dog is older than 1 year old they can be sedated and radiographs for an extended ventrodorsal radiograph
They’re then given a score /53 per hip and the lower the score the better

Question 19

What is Legg Calve Perthes and what group does this commonly affect?

Answer 19

avascular necrosis- blood supply to the ball part (femoral head) of the hip joint is temporarily interrupted and the bone begins to die
Effects small terriers commonly at 4 months old

Question 20

How do we treat Legg Calve Perthes?

Answer 20

femoral head and neck excision- send it for histology and culture

Question 21

What is the most common type of Hip Luxation?

Answer 21

Craniodorsal- femoral head is forced over the dorsal acetabulum

Question 22

What should we always try prior to surgery when treating a Hip Luxation?

Answer 22

Closed reduction- aims to replace a dislocated hip back into the socket through manipulation of the limb without surgically exposing the joint

Question 23

What common problems are associated with the Tarsus? (4)

Answer 23

OCD- Osteochondritis Dissecans
Achilles Degeneration/ Rupture
Plantar Ligament Collapse
[Trauma/ luxations]

Question 24

What would we expect to see in a physical exam of a patient with OCD in the tarsus? (3)

Answer 24

Upright hocks- will stand upright to take the pressure off
Tarsal effusions or thickening
Reduced flexion and pain

Question 25

Achilles tendon degenerations are more common in….

Answer 25

Middle aged large breeds such as Dobermans, Labradors

Question 26

What is the characteristic gait of a dog with Achilles damage?

Answer 26

Claw or flat footed with dropped hock

Question 27

How is Achilles rupture treated?

Answer 27

Resection & reconnection
Can use a prosthetic augmentation- artificial ligament sutured in

Question 28

What is characteristic of plantar ligament degeneration/ collapse?

Answer 28

Banana foot
[also increased movement at intertarsal joints when manipulated]