Large Animal Osteoarthritis: Diagnostics and Treatments

Question 1

name the components of the joint that are affected with OA and associated diagnostics

Answer 1

1. subchondral bone: radiograph, CT, US, MRI, nuclear medicine
2. articular cartilage (hyaline): radiographs (indirect), US, MRI, CT (indirect via contrast), arthroscopy!
3. joint capsule/supporting ligaments: US, MRI, arthroscopy, synoviocentesis
4. synovial membrane:
5. synovial fluid: US, synoviocentesis, arthroscopy

Question 2

identify diagnostic tools that can be used to identify OA in a clinical patient and explain the benefits of each

Answer 2

1. static palpation: feel for pain, effusion, and range of motion
2. dynamic: use different surfaces, straight lines/circles, and faits to exacerbate lameness
3. flexion tests: change in lameness and ROM after?
4. diagnostic analgesia: nerve and joint blocks

Question 3

explain the difference in disease versus symptom modifying treatments

Answer 3

disease modifying: directly slows or reverses the progression of disease (ex. arthroscopy to remove an osteochondral fragment)

symptom modifying: improves function and decreases the clinical signs of the disease (ex. oral phenylbutazone to improve lameness)

Question 4

describe the spectrum of treatment options for a large animal with OA

Answer 4

broad! depending on money and communication

1. medical:
   -systemic (NSAIDs: bute, banamine, firocoxib, acetaminophen; SYMPTOM MODIFYING),

-or local
-(joint health, hyaluronic acid, polysulfated glycosaminoglycan (disease AND symptom modifying)
-topical NSAIDs, intra-articular injections of corticosteroids or hyaluronic acid; (symptom modifying)

2. shoeing: lessen concussive forces, add stability, increase balance, provide hoof leverage but regular shoeing/trimming intervals are key! (symptom modifying)
3. surgical: arthroscopy, implant placement, arthrodesis/ankylosis (fuse joints)- disease and symptom modifying
4. rehabilitation: exercise or other modalities