Ortho 1 Flashcards
what is the definition of primary osteoarthritis in cats? what is the most important risk factor?
caused by age, obesity (systemic factors), genetic predisposition.
age most important
what is the most common type of osteoarthritis in cats, primary or secondary?
primary
what is the definition of secondary OA in cats?
due to biomechanics factors affecting the joint (trauma, development abnormalities, instability, mechanical overload)
define primary OA in dogs.
due to genetics, age, systemic factors (obesity)
define secondary OA in dogs.
secondary to primary inciting cause.. a treatment needs to address primary cause
following injury or insult to affected joints (CCL rupture, articular fx or OC initiates biochemical cascade leading to arthritis)
which is more common in dogs, primary or secondary OA?
secondary
what are the most common C/S of OA in a dog?
lameness, reluctance to exercise, inactivity stiffness, pain, joint effusion, muscle atrophy, joint thickening, altered ROM, altered gait, altered behaviour
what are the most common C/S of OA in a cat?
most cats don’t show C/S recognized by owners!!!
more behaviour changes than clinical ones
changes in mobility, activity level, increased time spent resting, changes in social behaviour, increased vocalization, objection to being handled, changes in play and hunting, overall posture, pain on flexion and extension, crepitus upon manipulation of joint, muscle atrophy, joint thickening
client-based questionnaires or checklists regarding OA have been used in both research and clinical settings. What utility do these tools have?
provide a summative score that can assess severity of disease at outset and response to treatment
what PE findings are expected in a cat with OA?
gait changes (walking, jumping), pain on flexion and extension, joint effusion, crepitus, decreased ROM/ROM asymmetry, periarticular thickening/fibrosis, muscle atrophy
what PE findings are expected in a dog with OA?
gait abnormalities/changes, lameness, pain on flexion and extension, joint effusion, muscle atrophy, joint thickening, altered ROM
what are the radiographic signs of OA?
often nonspecific!
- osteophytosis/periarticular new bone formation
- enthesophytes
- subchondral bone sclerosis
- joint effusion
- ST swelling/thickening
- intra-articular mineralization/narrowed joint space
- cysts
- capsular or extra-articular mineralization
what are osteophytes?
outgrowth of bone at the margin of an articular surface
what are enthesophytes?
bone spurs forming at ligament or tendon insertion into bone; growing in natural direction of pull of ligament/tendon
what is the most valuable and cost-effective means to assess joint?
arthroscopy
do radiographic signs and C/S of OA always correlated? if no, then how do we interpret our findings?
no
complete systemic assessment is needed to rule out other metabolic abnormalities and provide a baseline before NSAID therapy
in cats with OA, treatment is often aimed at _______. why?
alleviating chronic pain
because arthritis is not dx in many cats until it’s advanced :(
tell me about the multimodal treatment options for feline OA
Pain relief:
- NSAIDs
- gabapentin, tramadol
- WEIGHT MGMT!!!
Joint supplements:
- essential fatty acids (DHA and EPA)
Chondroprotective agents:
- glucosamine and chrondroitin sulphate
Controlled exercise
Environmental mods
Rehab
Polysulfated glycosaminoglycans (PSGAG)
monoclonal antibodies (emerging)
surgery as a salvage procedure when medical mgmt doesn’t work
how do you diagnose panosteitis?
PE: shifting leg lameness, pain on palpation of long bones
rads (diagnostic): circumscribed opacities in medullary canal (patchy opacities, “thumb prints”)
how do you diagnose HOD (hypertrophic osteodystrophy)? PE and diagnostic tests
PE: painful swelling of metaphysical long bones, often see systematic illness (fever, lethargy, inappetence, d+)
rads (diagnostic): Lucent line in metaphysial region parallel to physis = double physis
- periostea or endosteal reaction in physis region
- subperiosteal hemorrhage –> new bone formation, usually palisading along periosteum or bridging the physis
how do you diagnose avascular necrosis of the femoral head? PE and tests
pe: mild to severe non-weight bearing lameness in pelvic limbs; mild cases may be subclinical; acute pelvic limb lameness in a small breed dog
rads (diagnostic):
- progressive radiopacity of lateral epiphyseal area of femoral head
- followed by lysis of femoral head (moth eaten, apple core appearance)
- flattening and lucency of the head
how do you diagnose multiple cartilaginous exostosis? PE and testing
PE: pain present if exostosis assoc with tendon, ligament, vessel, or spinal cord compression
rads (used as monitoring tool): single or multiple bony masses within cortex, medullary cavity confluent with host bone with distinct trabecular pattern
how do you diagnose slipped capital femoral epiphysis? PE and testing
PE: acute or chronic pelvic limb lameness, painful coxofemoral joint upon manipulation, inability to jump, 1/4 cases are bilateral
rads:
- widening and lateral displacement of capital femoral growth plate with progressive resorption and sclerosis of femoral neck
acute pelvic limb lameness in a cat
how do you diagnose OCD? PE and testing
PE: consider in any young large/giant breed dog with lameness and swollen painful joints! Always look at contralateral joint bc often bilateral
rads (diagnostic):
- defects in subchondral bone
- flattening of contour
- sclerotic margins
- ± mineralization of cartilage flap
mainly at humeral head
What is hypertrophic osteopathy? HO
periostea reaction of distal extremities
can be any bone and can be bilaterally symmetric
most often associated with primary or metastatic neoplasia
