Ortho 1 Flashcards
what is panosteitis?
a self limting disease of the long large bones of large and giant breed dogs (usually young animals/juveniles).
most commonly affects the ulna, then the radius, humerus, femur, and tibia
what causes panosteitis?
exact cause is unknown; could be a result of high protein and calcium in the feed. dogs that weigh more are at an increased risk
how do you diagnose panosteitis?
signalment, history, PE, and radiographs. no systemic signs of illness are present
on rads: patchy opacities (thumb marks)
you see a 5mo bernese mountain dog with a painful right left forelimb. on radiographs you see circumscribed cortical bone opacities in the medullar of the ulna. how will you treat this dog?
exercise restriction, NSAIDs, or if severe pain, hospitalization and opioids. prognosis is good to excellent.
what are the major risk factors for OA?
age: as chondrocytes age they produce lower quality matrix and they are less able to respond to the environment and are not able to repair themselves as well
obesity: increased load on the joints
spaying/neutering: increased risk of many ortho diseases
briefly describe the pathogenesis of OA
there are changes in ALL tissues of the synovial joint: the articular cartilage, subchondral bone, osteophyte and entheophyte formation, synovial inflammation, and fibrosis
difference between osteophyte and enthesophyte
osteophyte: outgrowth of bone at the margin of an articular surface
enthesophyte: a bone spur forming at ligament or tendon insertion into bone, growing in natural direction of pull of ligament/tendon
OA is usually secondary to…
some other joint abnormality like instability, laxity, fracture, etc.
clinical signs of OA in dogs and cats
dogs: reluctance to exercise, exercise intolerance, stiffness, lameness, inability to jump, behavioral changes, abnormal gait, muscle atrophy, joint swelling, joint effusion, crepitation, gradually worsening
cats: more hidden, reduction in activity, reluctance to jump, unkept appearance, not being able to jump as high
what do you expect to see on rads with OA?
osteophytosis, enthesophytes, effusion, soft tissue swelling, subchondral sclerosis, intra-articular mineralization, subchondral cysts
______ is the most valuble and cost effective means to assess joints
arthroscopy
if there is any doubt about underlying disease process of the joints, you should
do arthrocentesis and evaluation
best way to manage OA? (non surgical)
weight management
exercise modification
NSAIDs
solensia for cats
omega 3s
what surgical treatment options are there for OA?
joint debridement and micropick, joint replacement, joint excision (femoral head osteotomy), arthrodesis (fusing joints), amputation
osteochondrosis is a disorder of the process of ________
endochondral ossification
describe the difference between these terms:
osteochondrosis latens
osteochondrosis manifesta
osteochondrosis dissecans
latens: an early microscopic lesion
manifesta: subclinical lesions on rads but clinically present
dissecans: cartilage flaps present, clinical signs present
where does the dog tend to get osteochondrosis?
the humeral head, medial humeral condyle, on the femoral condyles, trochlear ridges of the talus
what causes osteochondrosis?
usually inherited as polygenetic trait
joint morphology/conformation plays a part as well
rapid growth (large/giant breeds)
describe the pathogenesis of osteochondrosis?
not fully understood, suspect an avascular necrosis of developing epiphyseal cartilage (damage to vessels)
could also be a defect in the subchondral bone
a 6mo lab comes to you with lameness and exercise intolerance, mainly in the front legs. on PE, you find some joint effusion in the shoulder joints and the dog seems painful. differential? next steps for diagnosis?
osteochondrosis
i would do rads to look for: flattening of subchondral bone, concavity, sclerotic bone, mineralized cartilage flaps, joint mice
if available, arthoscopy is also a good option
in which cases can you non surgically manage osteochondrosis? what does non surgical management include?
young dogs with mild clinical signs, no joint mice, or are in unimportant location
in dogs with advanced secondary OA where it’s hard to remove a flap (like on the talus)
NSAIDs, exercise restriction, crate confinement, dietary supplements like omega 3s, glucosamine, weight control, calorie restricted diet
true or false: in young dogs with shoulder OCD, you should recommend vigorous exercise
true!
what surgical options are available for treating oesteochondrosis?
arthrotomy or arthroscopy, flap excision and joint mouse retrieval
what are the goals of doing a surgical procedure for oestochondrosis?
relieve clinical signs and restore pain free function
prevent or delay onset of secondary OA
the least common location for OCD is
the stifle
which locations for OCD have the best prognosis and which ones have the worst?
best: shoulder
medium: stifle, medial humeral condyle
talus: worst
what are your differentials for an acute pelvic limb lameness in a small breed dog?
hip luxation, hip dysplasia, avascular necrosis of the femoral head, patellar luxation, CCLR, neoplasia, infection
what is avascular necrosis of the femoral head and who gets this disease?
a non-inflammatory aseptic necrosis of the femoral head and neck, happens in small breed dogs. ages 4-11 months. the cause is not understood.
avascular necrosis of the femoral head often presents as
a mild intermittent lameness shifting to an acute non weight bearing lameness
on rads, avascular necrosis of the femoral head looks like an
apple core
left side is abnormal
treatment for avascular necrosis of the femoral head
femoral head and neck excision
total hip arthroplasty
true or false: rest and conservative therapy is very successful for avascular necrosis of the femoral head
false! it is successful less than 25% of the time
differentials for an acute pelvic limb lameness in a young cat?
hip luxation, hip dysplasia, patellar luxation, CCLR, neoplasia, infection, and slipped capital femoral epiphysis
what is “slipped capital femoral epiphysis”
a NON traumatic process, mostly in cats, esp in male neutered overweight cats, often bilateral
presents: lameness, poor jumping, weakness, crepitation, pain
treatment options for slipped capital femoral epiphysis?
femoral head and neck excision
total rip replacement
** better with early surgical repair
what rad view do you want to do if you are investigating a slipped femoral epiphysis?
frog leg view
what is hypertrophic osteodystrophy?
occurs in young rapidly growing dogs, usually large breeds,
swelling of distal metaphyses of the radius, ulna, tibia
a young large breed dog presents for fever, anorexia, pain, and inability to walk. on rads you see a double physis line. diagnosis?
hypertrophic osteodystrophy
prognosis for hypertrophic osteodystrophy?
good! using symptomatic therapy, will see improvement in 7-10 days and the bony changes will take a few months to improve
what is hypertrophic osteopathy and how is it different than hypertrophic osteodystrophy?
osteopathy: a periosteal reaction of the distal extremities, usually associated with primary or metastatic neoplasia (like in the lungs)
oesteodystrophy
