Final Exam - Joint Disease of the Stifle Flashcards
what are 3 reasons a dog will have a stable stifle palpation despite suffering from cruciate disease?
- patient pain & excitement - use heavy sedation for a solution
- early, partial rupture
- severe peri-articular fibrosis (buttress) in chronic cases
other than body weight, what clinical factors drive CCL surgical decision making?
activity, purpose level, client compliance, degree of rupture, finances, skeletal conformation, tibial plateau angle, patient history
what are the objectives of CCL surgery?
- elimination of pain/lameness - client’s main concern
- debridement of diseased tissue (CCL & meniscus)
- restoration of function
- slow the progression of OA
what is the grading system used for medial patella luxation?
grades I-IV
what 4 procedures are used for surgical correction of routine medial patellar luxation?
- trochleoplasty - deepen the groove
- tibial tuberosity transposition - re-aligns patella
- medial retinaculum release
- lateral reinforcement - imbrication
when is an extracapsular repair indicated for a dog with a CCL rupture?
sedentary, geriatric dogs, normal BCS, compliant clients, TPA <26-28 degrees, & small to medium breeds
when is an TPLO indicated for a dog with a CCL rupture?
active/high energy working dogs, obese, non-compliant clients, any TPA but > 30-32 degrees, & any size breed
what is the most common cause of pelvic limb lameness in dogs?
cranial cruciate ligament rupture - excluding fractures/joint luxations, CCL rupture until proven otherwise
why are acute CCL ruptures less common than chronic ruptures in dogs?
it involves the sudden mechanical overload of a normal CCL causing failure & instability
90-95% of CCL ruptures involve a chronic, progressive, mechanical, & possibly degenerative breakdown of collagen fibers within the ligament
even when the client describes the primary complaint as acute lameness, why do you suspect chronic?
typically a chronic history of waxing/waning signs until complete failure
T/F: up to 50% of dogs rupture the opposite ligament within one year of the initial injury
true
what breed is most commonly affected by CCL ruptures?
labs
what do you expect to see on physical exam of a dog with a complete CCL rupture?
cranial drawer sign & cranial tibial thrust
pronounced lameness from joint instability from incompetent CCL
why may you not see a drawer sign/tibial thrust in a dog with a partial CCL tear?
some fibers remain intact & functional preventing these signs
T/F: both complete & partial tears of CCL can have meniscal tears
true - more common with complete tears
what is the effect of CCL rupture as far as stability of the joint?
mechanical instability during weight bearing - cranial tibial thrust
causes persistent weight bearing lameness, typically grade 2-3/5
what is the effect of CCL tears on development of OA?
mild to moderate OA present at the time of the injury or that will progress after the ligament rupture
causes insidious waxing/waning lameness that progresses over time
how does a CCL rupture cause meniscal injury?
the tears commonly propagate in a longitudinal manner within the caudal pole of the medial meniscus - bucket handle tear
mild to moderate weight bearing lameness will acutely worsen at the time of meniscal injury
what is the sit test?
tool used to differentiate the source of a pelvic limb lameness in dogs
if positive - lameness is likely due to pathology of the stifle, if not, pathology of the hip
what is a cranial drawer test?
test that evaluates the stability of the stifle joint as assessed by the manipulation of the distal femur & proximal tibia
what is a positive cranial drawer test?
tibia can be moved cranially in relation to the femur more than the normal 2-3mm & the endpoint is indistinct - finding is diagnostic for a CCL tear
what is a positive tibial compression test?
test that mimics the mechanical loading of the stifle during weight bearing - stifle is positioned in a weight bearing position stabilizing the joint with one hand with the index finger of that hand positioned along the patellar tendon with the distal foot grasped & stabilized with the other hand
pressure is placed on the distal most hand while observing the tibial tuberosity for cranial displacement
what is a cranial tibial thrust?
movement of the tibia during a positive tibial compression test that is diagnostic for a CCL rupture
what is a meniscal click?
if concurrent injury to the meniscus occurs, a clicking sound may be heard or felt as the stifle joint is put through its ROM - absence of one doesn’t mean the meniscus is healthy