Orthopedics

Question 1

What is osteochondrosis? It affects what kind of dogs

Answer 1

Failure of endochondral ossification in Large to giant breed dogs 4-7 months

Question 2

What is Osteochondritis Dissecans?

Answer 2

Osteochondrosis with significant inflammation

Question 3

How do we treat Osteochondritis Dissecans? Goals of treatment?

Answer 3

We treat this surgically
Remove cartilage flap and joint mice, or cartilagenous pieces
Stimulate sub-chondreal bone formations and new cartilage formation

Question 4

What is the theory on how osteochondrosis occurs?

Answer 4

Due to an abnormal conformation there is increased pressure, and so less perfusion. This doesn’t allow the cartilage to transform to bone. So cartilage thickens and you get fibrous tissue underneath, and cartilage eventually degrades. (leads to synovitis, lameness etc)

Question 5

Which meniscus is most commonly damaged?

Answer 5

o Medial meniscus is most commonly damaged

Question 6

What is pathopneumonic for a coxofemoral luxation?

Answer 6

o Prelvic limb adducted and externally rotated

Question 7

What type of luxations are most coxofemoral luxations?

Answer 7

• 95% are CRANIODORSAL

Question 8

What is the Outerbridge Classification?

Answer 8

0 to 5
0 = normal cartilage, 5 = eburnation

Grade 0 = normal cartilage
Grade 1 = cartilage with softening and swelling, mild, superficial fibrillation
Grade 2 = partial thickness defect. Fissures on the surface don’t reach the subchondral bone
Grade 3 = Fissuring to the level of the subchondral bone
Grade 4 = exposed subchondral bone
Grade 5 = Eburnation

Question 9

What does Synovial Fluid do?

Answer 9

It provides nutrients to the cartilage and lubrication

Question 10

What do Synoviocytes type 2 produce?

Answer 10

Hyaluronic acid

Question 11

What 3 things do you see on radiographs for animals with osteoarthritis

Answer 11

o	See synovial effusion – white density seen within joint
o	osteophytes (>2wks)
o	Subchondral bone sclerosis

Question 12

What does gross inspection of synovial fluid tell you? – vol, color, turbidity, cell count, viscosity

Answer 12

Vol = more - problems? DJD? inflammation? sepsis?
Colour/Turbidity = clear to turbid = DJD; turbid = inflammation, turbid/opaque = sepsis Cell count = more cells = inflammation, few = DJD
Viscosity = less? DJD, more = inflammation, thick in sepsis

Question 13

What 4 things can you do to manage osteoarthritis

Answer 13

1. Diet restriction
2. Exercise restrition
3. Chondroprotective agents
4. +/- alternative drugs?

Question 14

Name 4 substances given to a dog with osteoarthritis

Answer 14

1. Fish oil (omega 3)
2. Pentosan polysulphate
3. Polysulphated Glycosaminoglycans
4. Glucosamine & chondroitin sulphate

Question 15

What is the most frequent joint affected by OCD

Answer 15

Shoulder (+++), then elbow(++), hock(+), stifle & sacrum (-)

Question 16

What are the clinical signs of OCD in the elbow? Treatment?

Answer 16

Holds elbows in, medial condyle of the humerus affected 
Surgical osteochondroplasty (guarded to fair prognosis)

Question 17

Clinical signs of OCD in the stifle

Answer 17

Caudal aspect of the lateral condyle of the femur

Question 18

Shoulder luxations - common types

Answer 18

80% OF ALL LUXATIONS ARE MEDIAL (18% ARE LATERAL)

Question 19

When do you use a Velpeau splint?

Answer 19

For a medial shoulder luxation – will push humerus out (lateral joint capsule still intact)

Question 20

When do you use a Spica splint?

Answer 20

For a lateral shoulder luxation.

Question 21

When do you use an Ehmer sling?

Answer 21

For a coxo-femoral luxation (cranio-dorsal)

Ehmer sling for 10d (otherwise will reluxate)

Question 22

When do you use Hobbles?

Answer 22

For a coxo-femoral luxation which is ventral (happened b/c of leg coming OUTWARD – prevent this movement with hobbles)

Question 23

Should you attept a closed reduction with a congenital shoulder luxation?

Answer 23

*don’t attempt closed reductions in congenital luxations

Question 24

Bicipital Tenosynovitis - clinical signs

Answer 24

Strain injury of the biceps brachia tendon and is relatively frequent cause of lameness in the medium-to-large breed adult dogs
- Insidious onset (gradual)
- Intermittent lameness worsens with exercise
- Atrophy of shoulder muscles
- Positive “bicipital tendon” test (may not be specific to tendon) → will also be positive on OCD
Shoulder pain may NOT be evident in chronic cases

Question 25

Bicipital Tenosynovitis - treatment (medical)

Answer 25

• Strict rest for 12wks (up to 7mo)
• Anti-inflammatories
  o Depo-medrol intraarticular - steroid (20-40mg) ONCE → breaks inflammation down
  *NOTE steroids are deleterious to cartilage and tendons (can rupture tendon)

Question 26

Bicipital Tenosynovitis - treatment (surgical)

Answer 26

• Bicipital tenotomy (arthroscopy) - cut the tendon
  o Tendon is still attached to joint capsule
  o Will then fuse back to joint and return to function
• Bicipital tenodesis (open approach)
  o Transect diseased tendon and reattach it to proximal humerus → do this is working animals
  o Velpeau sling for 3wks
  o Rest for 6wks

Question 27

Supraspinatus Tendinopathy

Answer 27

• With shoulder lameness may see mineralization along this tendon