Lecture 2: Hip Dysplasia/Sx Management Flashcards
What do you do if a dog is clinically normal, but radiographically abnormal?
You dont do shit;
but tell owner to keep an eye for early signs of OA/hip dysplasia
What is CHD?
canine hip dysplasia
developmental diseas of dogs
characterized by hip laxity/loosening in the hips
No cure
T/F
CHD is not congenital
TRUE
What are the factors that contribute to CHD?
genetics/hereditary factors
environment
rapid growth
How does the ligament of femoral head contribute to joint stability?
connects the head of the femur to teh acetabulum
How does joint fluid contribute to CHD?
increased fluid = increased pressure = pushes the head out of acetabulum
How does the joint capsule contribute to CHD prevention?
stabilizer of the coxofemoral joint
eventual thickening may help prevent CHD
painful as juvenile but with time thickening will resolve
Muscles act as _______ of the joint
secondary stabilizers
How would rapid growth of an animal contribute to CHD?
rapid growth may result in disparity of muscle:bone (bone grows faster
What 3 muscle groups contribute to hip stability?
iliopsoas, pectineus, adductor
What information is important to receive from owners to initiate tx of CHD?
at least orthopedic exam /radiographs
What is the common signalment of a young dog with CHD?
young, rapidly growing, large breed
painful from laxity results in:
synovitis
cartialge wear/tear
possible microfracture of acetabular bone
What is the common signalment of older/middle aged dogs with CHD?
usually painful from secondary OA
What are the clinical signs of CHD?
decreased acitvity difficulty rising reluctant to run or climb stairs bunny hop gait narrowed stance hyperextened hocks
What would you expect to find on a physical exam of a dog with CHD?
Muscle atrophy hip pain on extension decreased hip ROM palpable crepetation symmetrical HL lamness
What is an Ortolani sign?
maneuver to elicit hip subluxation and reduction ie laxity
What is the technique to pdx an ortolani sign?
adduct stifle, lift greater trochanter, push femur dorsally, apply light pressure on greater trochanter until it pops
Which has a better prognosis, a sharp pop, or a soft-mushy like movement wiht regards to Ortolani signs?
Pop is better
mushy has worse prognosis
Whhat is the most important thing in regards to radiographs?
POSITIONING
What position do you want the dog to bein to take radiographs for CHD?
need V-D
straight pelvis
femurs fully extended
femurs straight not rotated
patella in center of trochlear groove
fabellae bisected by medial and lateral femur cortices
Hip dysplasia is classified as __% of femoral coverage by _____
50%
acetabulum… DUH
How do you tell if there is 50% coverage?
make circle around the headm ID cneter, then draw line cranial to caudal margins of acetabulum and center
Pretty much just dont be an idiot
What are you looking for on a radiograph to determine CHD?
well besides 50% coverage…
secondary OA- morgans line/line for osteophytes
periarticular bone formation on femoral neck
acetabular infilling
subchondral bone formation
What are OFA radiographs?
Dont really seem important-
need VD pelvis only
grades from excellent- severe dysplasia
What 3 veiws do you need for PennHIP radiographs? and what do they tell you?
distracted view- laxity
compression view- goodness of fit
hip extended view- evaluate for OA
What is the distraction index?
measure of hip laxity 0-1
distance the head can be displaced from the acetabulum
What does the DI score indicate?
near 0 = little laxity
1 = high degree of laxity
less than .3 is considered ‘normal’
HD unlikely to occur
What are the 2 tx options for HD?
medical management
surgery!
what are the surgical options to tx HD?
JPS
TPO
Femoral Head/Neck excision
Total hip replacement
What must you consider when selecting surgery technique?
age
secondary OA changes
desired outcome
What is JPS?
Juvenile Pubic Symphysiodesis
elctrocautery of the ventral portion of pubic symphysis
What is the result of JPS?
stops growth ventrally
continues dorsal growth- more coverage of the femoral head
When is it best to perform JPS?
12-16 weeks of age
What is the potential draw back of JPS?
future breeding could be issue
recommend spay/neuter, because will not be able to tell older dog had procedure
What is the other Sx option for an immature dog with HD?
Triple pelvic osteotomy
What is a TPO?
osteotomy of pubis, ischium and ilium
What does a TPO result in?
ventral rotation of acetabular segment-> more dorsal coverage of femoral head
Candidates for TPO?
5-10 months old
minimal or no radiographic evidence of OA
good femoral head capture-> crisp pop not mushy
T/F
It is recommend to wait linger before Sx with TPO because many dogs will spontaneously improve after skeletal maturation
FALSE
EARLY is recommended because OA will develop fast, the second part is true
Are bilateral TPOs common?
YES, however stagger Sx
What are some complications with TPO?
omplant loosening
narrowed pelvis
urethral obstruction (creating a smaller opening)
femoral neck impingement
What is a FHO?
Femoral head and neck excision
salvage procedure
T/F
there will aways be a gait abnormality post op for FHO, but a more predictable outcome occurs when preformed in dogs less than 40lbs
TRUE
____ post op FHO is extremely important bc normal fx is hard to regain
Physical rehabilitation
What is teh second salvage procedure to Sx repair old dogs with HD?
THR- total hip replacement
T/F
Total hip replacements will result consistently in 80% of animals regaining original function
FALSE?
Kind of a shitty question on my part, but THR gives full range of motion, so you could extrapolate and assume those animals regain full fx?
What are the 2 types of THR?
cementless and cemented systems
T/F
THR and FHO both typically require bilateral operation
FALSE
THR usually unilateral because it is comfortable/easier recovery
Who are candidates for THR?
only problem is HD/OA
No neuro issues
No neoplasia
No CCL injury
No infections
T/F
Complications with THR are uncommon, and are not serious issue
FALSE
uncommon but very serious
What are the THR complications?
infection
luxation
loosening
femoral fx affected
T/F
HD is usually caused by a singular event
FALSE
multifactorial
T/F
All dogs with HD will show signs
FALSE
T/F
Medical management is usually unsuccessful in older dogs, there for it is in the best interest of the patient/client to recommend Sx immediately
FALSE
Medication is always first
What is a limiting factor for the OFA hip radiographs?
Have to be at least 2 years old
