Ortho Flashcards
What are the purposes of vet orthopedics?
to improve comfort and function, improve QOL
What’s the most innervated spot on the bone?
periosteum is highly innervated and so is subchondral bone (underneath cartilage)
What are the landmarks of the cranial drawer test?
have a thumb on the caudal aspect of femoral condyles with index on the patella. Other hand’s thumb is on the head of the fibula with the index on the tibial crest
If a positive cranial drawer test is found, what does this mean?
It means there is rupture of the cranial cruciate ligament
How do you perform the tibial thrust test?
Hold the stifle in a slightly flexed position, index finger of one hand over the tibial crest, other hand flexes and extends the hock.
You get a positive tibial thrust test, what does this mean?
cranial cruciate ligament is ruptured
What does a negative cranial drawer but positive tibial thrust test indicate?
dynamic instability, but static stability
Explain when the medial and lateral collagen bundles of the CCL are taught or relaxed
Medial bundle is taught in both flexion and extension (if it is I ntact, there is no drawer in flexion or extension); the lateral bundle is only taught in extension but not in flexion (you can have a partial rupture in which only one bundle tears)
Which bundle is typically torn first?
medial bundle > lateral
What happens if you lose the medial bundle first but still have the lateral?
You will lose the flexion stability and get a positive drawer in flexion
T/F: you can just test cranial drawer or tibial thrust in extension
False: always test in extension and flexion –> flexion will help to elucidate early tears
What’s the weight limit max of extracapsular techniques?
Dogs < 15 kg
What kind of stability does extracapsular techniques provide?
dynamic and static stability
What kind of stability does osteotomies or ostectomies provide?
dynamic stability by eliminating shearing forces and so thurst.
What sizes of dogs are good for osteotomies?
all sizes
Give examples of osteotomies
TPLO, TTA, CCW, CBLO
T/F: you normally get a lot of osteochondrosis with patellar luxation
False: you don’t
What procedures can we do for a patellar luxation?
Desmototomy (soft tissue surgery - only used as sole treatment in young pups, but often with other treatments), groove reconstruction procedures (depends trochlear groove), limb alignment procedures, distal femoral osteotomy
What are the only two groove reconstruction surgeries you can do in mature animals?
wedge or block recession. Wedge = take a triangle out of bone then put it aside then take out another triangle of same size and put the old block back in; Block = cutting on either side of highest point of trochlea, remove block, chisel down sides then put block back in
What is a sequela of hip dysplasia?
Osteoarthritis
Why do dogs with hip dysplasia get joint laxity?
Excessive joint fluid, low pelvic muscle mass giving it stability, hormones, nutritional excess (calcium and vitamin D), IM injected polysulfated glycosaminoglycans (6 weeks to 8 months) < building blocks of cartilage can help improve hip laxity at a young age, increased body weight
What’s the earliest you can diagnose dyasplastic hip changes?
by 30 days, 4 weeks of age
What comes first on radiographs? Degenerative changes or osteoarthritis?
Before you see osteoarthritis, you will see degenerative changes on xrays
What is our job as a GP with detecting hip d ysplasia?
We need to detect it early, give a good diet recommendation. If you recognize it early, the more options of fixing are available.
Which dogs do not get hip dysplasia?
sight hounds (greyhounds, borzoi)
Why is there a honeymoon phase with hip dysplasia with less pain ?
This is the perarticular fibrosis phase which improves hip joint laxity
What are the two hip radiographs you can take for hip dysplasia and which one requires certification?
OFA is the extended hip view, false negative possible; PennHIP must have animal sedated/anesthetized, you need certification and requires 3 views (VD hip extended, compression view, distraction view)
What’s the compressed and distracted view?
Compressed is like a frog stance, you try put push those acetabulums into the joints as much as possible, the distracted view is that you try to push out the acetabulums as much as possible
All patients with hip dysplasia need _____ management
medical
What are the two surgeries you can do as prophylactic surgery on young dogs?
Juvenile pubic symphysiodesis (JPS) and pelvic osteotomy (double or triple)
What’s the age limit for a JPS?
12-20 weeks, palpable laxity
Pelvic osteotomy age limit?
younger than 10 months to 1 year
What do you briefly do in a JPS?
You do electrosurgery and use thermeal heat to kill the pubic symphysis growth. It fuses that part of the pelvis while the rest of the plvis grows and it grows to have better coverage of the acetabulum
How do you do a pelvic osteotomy?
Cut pelvis into 2-3 pieces and manually rotate it to get better acetabular coverage. Double osteotomy = don’t cut ischium and end up with slightly wider pelvic opening vs a triple < super invasive
What are some salvage procedures for hip dysplasia = for patients > 1 yo with OA
to eliminate pain from secondary OA, we do femoral head and neck excision (FHO) or total hip arthroplasty (hip replacement)
What’s the most common cause of hip luxation?
Traumatic
Most hip luxations luxate in which direction?
cranio-dorsal
How do you distinguish craniodorsal luxation and ventral luxation?
Craniodorsal luxation: legs aren’t equally as long, one is shorter; pops up overtop and sits on dorsal edge < non weightbearing. Ventral luxation: legs are gonna look longer rather than shorter, have internal rotation and abduction and is where the joint pops out and sits within the forament at bottom of pelvis
What’s the treatment for hip luxation?
you need to reduce it ASAP (closed or open within 3 days)
Ventral or craniodorsal has a better outcome with closed reduction?
Ventral
What’s the role of the anconeal process?
Engages with humerus and is to stabilize joint in mediolateral motion in extension
What’s typical signalement of ununited anconeal process (UAP)?
Large, giant breed dog, male > female, 5-12 months old and up to a third of these cases are bilateral (older = bilateral), weight bearing lameness worse after exercise
What kind of radiographs should you take for a UAP?
Neutral lateral, flexed lateral of both elbows
Why is flexed lateral the most important view for UAP?
It opens up the anconeal process
What’s the posture in terms of elbows and paws designed to unload medial joint compartment seen with medial coronoid disease?
Elbows are abducted, paws are turned outwards (externally rotated)
What’s the gold standard for medial coronoid disease diagnosis and why?
CT: allows quantification of incongruity, evaluation of subchondral bone (vs arthroscopy is just evaluating cartilage), but we can’t image the cartilage this way
Difference between osteotomy and osteoctomy?
Osteotomy = remove part of bone, osteoctomy = remove entire bone
What’s the alternative, more conservative management of elbow dysplasia?
NSAID, weight management, exercise modification, formal rehab, injections of steroids, stem cells, etc. radiation
What are the 4 nonsurgical management techniques for elbow dysplasia, specifically osteochondrosis dissicans?
small lesions in dogs younger than 6.5 months, mild clinical signs or joint mice; dogs with advanced secondary OA where clinical value of flap removal is limited; NSAIDs, exercise changes, rehab, dietary changes, weight control; Complete surgical removal of the flap
What are surgical management methods of osteochondrosis dissicans?
Arthrotomy or arthroscopy; flap excision and joint mouse retrieval; palliative techniques (curettage, abration arthroplasty, forage, microfracture); restorative techniques (fragment reattachment, osteochondral transplants)
Most common sites of OCD lesions?
Stifle (least common location), shoulder (males > females), medial humeral condyle, talus
Rank the prognosis of the OCD lesion sites (stifle, talus, medial humeral condyle, shoulder)
Best to worst: Shoulder > stifle + medial humeral condyle > talus
