Hip Disease

Question 1

what is the best prevention for juvenile hip disease

Answer 1

selective breeding
(hip laxity is highly heritable)

Question 2

what disease does juvenile hip laxity predispose to

Answer 2

osteoarthritis

Question 3

clinical signs of juvenile hip disease

Answer 3

varies from mild to severe depending on if laxity is functional or passive

requirement for surgery depends on level of pain/lameness

Question 4

functional laxity

Answer 4

pathologic laxity that occurs during normal weight-bearing

caused by:
- thickening of femoral head ligament
- high joint fluid volume
- low pelvic muscle mass
- obesity/rapid growth
- early spay/neuter

causes clinical signs and progressive OA

Question 5

passive laxity

Answer 5

laxity that only occurs during manual manipulation of the hips (ex. evaluated during pennhip rads)

presence of passive hip laxity is the NUMBER 1 risk factor for development of OA later in life

Question 6

is hip disease expressed throughout life or only in certain stages

Answer 6

continuous expression throughout life

Question 7

diagnosis for juvenile hip laxity

Answer 7

physical exam and radiographs (VD hip extended + pennHIP)

Question 8

PE for juvenile hip laxity

Answer 8

typically done under sedation

barlow: subluxing the joint
ortolani: reducing the jointback into place

laxity can still be present even if not palpated

Question 9

radiographs for juvenile hip laxity

Answer 9

VD hip extended: can ID subluxations and secondary DJD changes

pennHip: evaluates VDHE, compression view, and distraction view
- best for diagnosing PASSIVE hip laxity by calculating distraction index

Question 10

what is the best diagnostic method for breeders to use

Answer 10

pennHip radiographs - measure distraction index and recommend breeding the top 50% of “tightest” dogs

Question 11

at what age are pennHip radiographs most diagnostic

Answer 11

6 months or older

Question 12

treatment of juvenile hip disease

Answer 12

palliative care ONLY - cannot surgically prevent OA from chronic hip disease

some surgical options (JPS and TPO)

Question 13

juvenile pubic symphysiodesis (JPS)

Answer 13

only used in dogs <4 months

goal: early fusion of the pelvic symphysis to cause ventroversion of the pelvis

Question 14

triple pelvic osteotomy (TPO)

Answer 14

osteotomies of the ischium, pubis, and ilium to rotate the acetabulum

controversial; has high complication rates

Question 15

diagnosis of adult hip disease

Answer 15

1. clinical signs
2. PE
3. radiographs

Question 16

clinical signs of adult hip disease

Answer 16

mild to severe lameness
usually chronic and insidious
stiffness
bunny hopping gate (hind limbs)
exercise intolerance

Question 17

PE for adult hip disease

Answer 17

muscle atrophy (bilateral)
dorso-lateral protrusion of the greater trochanter
pain on hip extension
decreased hip ROM
crepitus (crackling)
ortolani sign

Question 18

radiographs for adult hip disease

Answer 18

VD hip extended view
1. joint conformation: <50% coverage of femoral head by the dorsal acetabulum
2. joint incongruity: non-parallel margins of dorsal femoral head and acetabulum
3. joint instability: subluxation
4. secondary DJD changes: thickening of femoral head/neck, osteo and enthesiophytes, flattened femoral head

Question 19

treatment for adult hip disease

Answer 19

conservative and surgical

Question 20

conservative adult hip disease management

Answer 20

weight loss/management
pain contol (NSAIDs)
supplements (EFAs)
exercise modificaiton - need to still be moving the joint

Question 21

surgical options for adult hip disease repair

Answer 21

1. THR
2. FHNE/FHO

Question 22

total hip replacement (THR) candidates

Answer 22

• clinical signs of OA
• unable to achieve desired level of activity
• unresponsive to conservative management
• no signs of infection

Question 23

THR outcomes

Answer 23

return to normal function BUT has higher risk of complications than FHNE

Question 24

cemented vs non-cemented vs hybrid THR

Answer 24

cemented: implants are held in by bone cement; easier but less precise

non-cemented: implants are held in by bony ingrowths that develop over time
- most common
- lower risk of infection, immune reaction, breakage, etc
- lateral bolts hold implant in place until bony ingrowth take place

hybrid: cemented stem + non-cemented cap

Question 25

femoral head and neck excision (FHNE) outcomes

Answer 25

same as FHO (femoral head osteotomy)

removal of the femoral head and neck to provide pain relief

eliminates pain but does NOT restore normal function - hip joint will fill in with scar tissue so gait will still be abnormal

Question 26

FHNE/FHO candidates

Answer 26

• previous failed repair of femoral head/neck fractures
• aseptic necrosis of femoral head
• pain from hip OA
• non-repairable acetabular fractures
• luxations that do not stay reduced
• failed THR implants

Question 27

aseptic necrosis of the femoral head

Answer 27

vascular trauma to the circumflex femoral vein leading to anoxia in the epiphysis –> osteoclast/blast remodelling –> revascularization

unable to catch inciting cause of vascular trauma

Question 28

signalment of ANFH

Answer 28

mild trauma at 4-12 months old

usually small breed dogs

Question 29

clinical signs of ANFH

Answer 29

unilateral NWB or partial WB

Question 30

what is the biggest risk factor for hip dysplasia in cats

Answer 30

hip laxity

uncommon but can occur