SA Ortho - Hip Dysplasia

Question 1

Hip joint development

Answer 1

Normal hips at birth - femoral head & neck are cartilaginous and under go endochondral ossification

Question 2

Hip joint congruence/stability

Answer 2

Stability is dependent on periarticular soft tissue that surrounds joint, critical stage in development

Question 3

Disparity in development

Answer 3

Bony part of joint
Soft tissue (muscles, ligs, JC)

Question 4

Hip joint injury progression

Answer 4

Laxity/instability
Poor joint congruence
Subluxation
Abnormal hip development

Question 5

Hip joint damage
Abnormal forces applied lead to …

Answer 5

Damaged cartilage surface, abnormal growth direction, reduced surface area

Question 6

Progressive degeneration of CHD

Answer 6

Periarticular osteophyte formation
Deformation of cartilaginous femoral head/acetabulum
Structural & biochemical changes in cartilage

Question 7

Factors for CHD development

Answer 7

Genetic
Nutrition influence
Environmental

Question 8

Genetic factors of CHD

Answer 8

Complex/poly genetic
Heritability 20-60%

Question 9

Genetic influences of CHD

Answer 9

Bony /soft tissue anatomy
Joint biomechanics
Growth rate
Joint fluid production/quality
Connective tissue quality
Hormone production

Question 10

Nutritional influences
High plane of nutritional affects growth rate

Answer 10

Rapid bone growth & weight gain
Over-loads soft tissue support
Increased frequency & severity of HD

Question 11

Dietary electrolyte balance w CHD

Answer 11

Low anion gap (Na, K, Cl) = less subluxation
Excessive synovial fluid may increase joint laxity

Question 12

Vitamin d

Answer 12

Over dose of Vitamin D caused increased calcium/decreased remolding

Question 13

Trauma to hips

Answer 13

Reduction of activity in predisposed dogs reduced the incidence rate

Question 14

Acetabular growth plates

Answer 14

Tripartite allows plastic changes to occur in the first 6 months
Bones normally close at 6m
- close at 5m in over fed dogs
- close at 7m in restricted diet dogs

Question 15

Signalment for CHD

Answer 15

Large fast growing breeds (GS, restrictive, Rotties)
Rare in small dogs/cats

Question 16

Clin signs

Answer 16

Lameness
Abnormal gait
NWB lameness
Low exercise, v ROM, muscle atrophy

Question 17

Physical exam findings
Laxity and pain

Answer 17

Pain in hip
-appearance of crepitus
- decreased ROM

Question 18

Ortolani signs

Answer 18

Sub lux
Abduction
Reduction
(Sedation)

Question 19

Radiographic views

Answer 19

Ventraldorsal with limbs pulled out and turned inwards, pressing heads into acetabular space and exposing the femoral head for viewing

Question 20

PennHIP - distraction Index

Answer 20

DI = d/r
Proper placement / displacement
Anything closer to 1 is bad

Question 21

What does the pennHIP DI measure

Answer 21

Presence of degenerative OA
Congruence (% covered)

Question 22

What factors influences scores on pennHIP DI

Answer 22

Breeds

Question 23

Conservative CHD management

Answer 23

NSAIDS, Rehab, weight management, holistic

Question 24

Surgical CHD management - disease modifying procedures

Answer 24

Juvenile pubic symphyiodesis (JPS)
Double/triple pelvic osteotomy

Question 25

Salvage procedures for CHD

Answer 25

Femoral head and neck excisional arthroplasty
Total hip arthroplasty

Question 26

What decreases usefulness / success of disease modifying procedures

Answer 26

Presence/progression of OA

Question 27

Purpose of disease modifying procedures

Answer 27

To subluxation tendency
Restore hip congruity/ save from further OA development