Exam 4 - M

Most common cause of osteoarthritis in cats

• Idiopathic

How does increase body weight cause osteoarthritis

• adipokines - affect cartilage turnover (leptin and adiponectin)

What is present in the joint that protects against inflammation when we think about gender related etiology

• estrogen protects against inflammation

Describe important concepts in the pathogenesis of osteoarthritis

• articular cartilage loses stiffness and tensile strength

• synovium produces pro inflammatory products resulting in pain

• subchondral bone promotes osteophyte formation

• note; all these together lead to mobility impairment and pain

Stage 1 OA

• proteolytic breakdown of cartilage matrix

stage two OA

• fibrillation and erosion of cartilage surface

stage three OA

• synovial inflammation

• phagocytosis of breakdown products, stimulates production of pro inflammatory mediators

four common sites of OA

• shoulder, elbow, hip and stifle

what is the classic history you will see in animals with OA

• slow to rise in the morning, but improves after exercise

• lameness after activity

do you see any soft tissue components of the joint with radiograph. Such as synovium, subdural bone and cartilage lesions

• No

True or false

radiographs correlate well with severity of clinical signs with OA

• false they do not correlate well with severity of clinical signs

what imaging modality is more sensitive than radiographs that is excellent for evaluating joint components such as cartilage defects and non-cartilage structures.

• MRI

• disadvantage = cost and requires general anesthesia

What gives you gross evaluation of the joint where you can directly assess cartilage damage?

• Arthroscopy

• note: serves as the therapeutic option concurrently

if you were doing synovial fluid analysis is it performed before or after imaging modalities

• after

you take synovial fluid sample and see 4000 total cell count with 10% neutrophils

What condition does this fall under?

• Osteoarthritis

• range: total cell count = 2-5000

• mononuclear cell percentage = 88-100

• neutrophils percentage = 0-12

list two approved disease modifying agents for osteoarthritis

• there are none

How do you manage osteoarthritis?

• multifactorial treatment

• weight control, activity management, pharmacological supplementation, joint injections, surgical management

what is your ideal BCS for weight control

• 4/9

List pharmacological supplementation that can be used as a multimodal approach to pain in OA

• NSAID

• Gabapentin

• Amantadine

• Solensia (cats)

• Librela (dog)

what disease modifying agent is chondroprotective that inhibits matrix metalloproteinases, cytokine inhibition and increases synthesis of hyaluronic acid, collagens and proteoglycans

• Polysulphated glycosaminoglycan (Adequan) - IM injection

one time injection that can be repeated in 1.5 years that creates an insoluble matrix

• SPRYNG

Hip dysplasia is abnormal development of the coxofemoral joint that is characterized by what two things

• Subluxation

• osteoarthritis

• note: biphasic presentation. etiopathogenesis is not fully understood

List environmental factors that can contribute to hip dysplasia

• rapid growth

• rapid weight gain

• excessive nutritional intake

• decreased pelvic muscle mass

• high activity

Joint laxity with hip dysplasia occurs with what two structures

• round ligament and joint capsule

True or false

The greater the laxity = greater damage

• true

laxity leads to inflammation which will then cause

• Osteoarthritis

Is hip dysplasia usually bilateral or unilateral?

• bilateral

What presentation may you see in a dog less than 6-8 months old with hip disclosure?

• abnormal gait (bunny, hopping , waddling asymmetric sitting, reluctant to jump)

• mild pain (unless severe subluxation or OA started)

During 10-12 months of age, why do these animals have a significant functional improvement?

• joint capsule fibrosis / tightening

• note: this is the end of the first biphastic phase

32% of dogs presenting for hip dysplasia also have what condition

• Cranial cruciate ligament rupture

Test that evaluates angle of reduction

• Ortolani

• push femur dorsally and then abduct

• note: clunk = positive ortolani

Test that evaluates an angle of subluxation

• Barlow test

which test laterally displaces the femur

• barden test

What are two reasons that you may not get a clunk with the ortolani maneuver aside from the hip being normal?

• shallow acetabulum

• severe OA

What radiographic screening evaluates passive laxity

• orthopedic foundation for animals (sedation)

• note: extension during positioning can falsely decrease joint laxity

Animals need to be minimum of how old to be certified with OA

• two years old

What radiographic screening evaluates laxity via passive distraction

• Pennhip (anesthesia)

• the greater the laxity the more likely OA will develop

Penn hip certification at what age

• 16 weeks

what requires vet certification pen hip or OFA

• Penhip

what is recognized by AKA pen hip or OFA

• OFA

what view is most useful for hip dysplasia?

• VD

what are radiographic findings indicative of hip dysplasia?

• Acetabular subchondral bone sclerosis

• less than 50% acetabular coverage

• thick femoral head

• osteophyte

• morgans line (enthesiophytosis)

True or false

only treat animal if symptomatic not radiographic

• True

what advantages does CT and MRI have when diagnosing hip dysplasia

• none

What are the two surgical procedures for hip dysplasia in adults

• FHO

• THR

what procedure can be done in a 4-6 month dog with no signs of OA

• JPS

• TPO

if the 4 to 6 month does have sigs of OA your only option is

• JPS

• note: TPO only if no signs of OA

6 to 10 month old dog with signs of OA

• THR

• FHO

True or false

in animal with hip dysplasia maximize medical management until patient becomes refractory and muscle mass begins to significantly decrease

• true

Juvenile pubic symphysiodesis is a salvage or preventative treatment

• prevent preventative

What is the goal with JPS (juvenile pubic symphysiodesis)

• Increase femoral head coverage by acetabulum via stopping pubic symphysis growth

• works by using the growth plate

True or false

JPS decreases OA progression rate and improves joint congruency.

• True

Ideal treatment age with JPS

• 12-16 weeks

• difficulty lies identifying dogs this early

Triple pelvic osteotomy is this salvage or preventative

• preventative

TPO (triple pelvic osteotomy) goal

• increase femoral head coverage by rotating the acetabulum by cutting pelvis in three places

What is an important criteria to consider TPO

• laxity present with no or minimal evidence of OA

TPO (triple pelvic osteotomy) age

• prior to 10-12 months (open growth plates)

True or false

arthroplasty is a salvage treatment

• True

True or false

the goal of total hip is to replace and stage joint disease with a prosthetic joint when all other medical management treatment options fail

• True

What is the alternate option to a THR that removes pain from joint by excision the joint

• femoral head and neck ostectomy

• note: failure of medical management options. functional outcome worse than with THR

• greater trochanter to lesser trochanter

True or false

After FHNO ( femoral head and neck ostectomy) crate rest dog for six weeks

• false

• immediately begin aggressive rehab program

List the developmental conditions that result in elbow dysplasia

• Ununited anconeal process

• medial compartment disease = medial coronoid disease osteochondrosis

• elbow in congruity

what dogs are affected with elbow dysplasia

• large breed rapidly growing dogs

true or false

elbow dysplasia is the most common cause of forelimb lameness.

• True

Elbow dysplasia is often unilateral or bilateral

• bilateral

Is elbow dysplasia more seen in young or older dogs?

• young growing dogs

Etiology of medial coronoid disease

• growth in congruency lead to abnormal stress on the medial coronoid process of the ulna

• end result is osteoarthritis

MCD (medial coronoid disease) is inherited in what dogs

• Labrador and Bernese mountain dogs

• males 2:1

• 6-18 months onset

with medial coronoid disease on physical exam you will see lameness and decreased ROM of elbow joint. Early on animal will feel pain and later on will have decreased ROM, especially in

• Flexion due to fibrosis

Animals with MCD will exhibit pain on physical exam with what two movements

• hyperextension

• direct palpation of coronoid process

what radiograph view can identify osteophyte formation in animals with MCD

• flexed lateral

True or false

with MCD joint effusion is usually minimal

• true

List four locations where you will find osteophyte formation with MCD in a flexed lateral

• proximal anconeal process

• cranial aspect of radial head

• cranial edge medial coronoid process

• caudal surface of lateral condylar ridge

• exam question

Most sensitive imaging modality for MCD

• CT

animals with MCD could be medically managed if owner is financially constrained or animal is at chronic end stage disease.

What is the gold standard treatment option

• surgical arthroscopy

Osteochondrosis signalment

• juvenile large / giant breed dogs

• 5-10 months

OC is often bilateral and most common location is

• shoulder

do you see effusion often present with OC

• Yes, often present and palpable

When radiographic animal with suspected OC in the elbow. What do you look for on radiographs

• divot of subchondral bone on the medial aspect of humeral condyle

With ununited anconeal process the anconeal process of the ulna does not forma boney union with the

• proximal ulnar metaphysis

normal fusion of the anconeal process occurs at what age

• 4-5 months

• so disease manifest clinically between 5-12 months

True or false

UAP may be a manifestation of OC

• True

UAP signalment includes large and giant breed dogs with poster child being

• German shepherds

• males two to one ratio

True or false

you can see UAP concurrently with 50% of animals who also have a joint in congruity

• True

Best radiograph view to diagnose UAP

• flexed lateral

what are the two different surgical approaches with UAP?

• Caught early = primary repair (lag screw with ulnar osteotomy)

• chronic disease = excision of anconeal process (50% are free of lameness)

Primary stabilizers

• cranial cruciate ligament

• collateral ligaments

secondary stabilizers

• menisci

• tendon

• fibrous joint capsule

cranial cruciate ligament travels

• caudolateral (axial aspect of lateral femoral condyle)

• to

• craniomedial (intercondyloid area of tibia)

Function of cranial cruciate ligament

• limits cranial tibia translocation

• prevents hyperextension

• prevents excessive internal rotation

The cranial cruciate ligament has two bands. cranial medial and caudolateral.

When are they taught

• cranial medial = extension and flexion

• caudallateral = extension

medial and lateral collateral ligaments prevent which motion

• medial = valgus

• lateral = varus

what meniscus contains a ligament that attaches to the femur.

Why is this important?

• lateral

• protects injury with a CrCL tear because it gets lifted with the femur due to the attachment

True or false

cranial cruciate ligament disease has a acute clinical presentation however it is a chronic degenerative process

• True

what are three conformation abnormalities that can predisposed to a cranial cruciate ligament?

• straight stifle joint

• narrow intercondylar notch

• excessive tibial plateau slope

An excessive tibial plateau slope results in

• cranial tibial thrust

• this causes repetitive micro trauma to the cranial cruciate ligament

signalment at risk for cranial cruciate ligament tears

• neutered males or females

• large / giant breed dogs

• breeds = labrador, boxer, newfoundland, rottweiler

What is the most common hindlimb lameness you will see?

• CrCL tear

On physical exam what is indicative of meniscal tear?

• Click with the range of motion

to test you can do on PE to demonstrate cranial translocation of the tibia

• cranial drawer

• tibial thrust