Joint conditions

Question 1

Osteoarthritis

Answer 1

Degenerative joint disease, osteoarthritis, arthritis)
More common in older animas, affecting any sex and breed. OA in younger animals is usually secondary to another condition, whereas is often primary in older animals.
Most common type of arthropathy in dogs and cats.
Often warm out of the stiffness.
May see intracapsular joint swelling, periarticular osteophyte formation, subchondral bone sclerosis, bone lysis, joint mice, initial widening of joint space.
S = Synovial effusion
A = displacing caudal fascial planes caudally.

Question 2

Septic arthritis

Answer 2

Occurs in young animals may occur from haematogenous (polyarticular) spread with no penetrating injury, in older animals may occur from penetrating injury (monoarticular). Rare in dogs, more common in foals. Causes severe pain swelling of affected joints. Demonstrate intracapsular joint swelling. Joint space may appear widened due to effusion, may see intracapsular gas from puncture or gas producing organism. Later in disease, may see subchondral bone distruction on all adjacent articular surfaces.

Question 3

Non-erosive Polyarthropathy

Answer 3

Diagnosis is based on history, clinical signs, lab tests, radiologic and pathologic features. Process of elimination.
Multiple joints are affected, most commonly stifle, carpus and tarsus.
Other than intracapsular swelling radiographs are usually normal. In chronic cases, secondary osteoarthritis may be seen.

Question 4

Erosive Polyarthropathy

Answer 4

Aetiologies
- Rheumatoid arthritis (most common)
- Feline non-infectious polyarthritis – erosive form
- Polyarthritis of the greyhound
No sex predilection, affects middle aged small to medium sized dogs, especially poodles and shelties.
An immune mediated disease with circulating auto-antiboides against IgG. Varying degree of lameness and joint stiffness. May be associated with systemic illness. Disease associate with degeneration of the joint capsule and ligaments, leading to joint laxity, luxations, and angular deformities.

Question 5

Synovial cell sarcoma

Answer 5

No sex predilection, more common in middle aged (6-8 years) medium to large sized dogs. Malignant neoplasm thought to arise from tenosynovial tissue in joints, bursa, or tendon sheaths. This tumour is uncommon in dogs and rare in cats. Most commonly affects the stifle and sometimes the elbow. Slow growing non-painful mass. Initial radiographs demonstrate a soft tissue mass at the joint, as the disease progresses, lytic lesions of multiple bones of the joint are present, ragged lysis of cortical bone at attachments to synovium is seen.

Question 6

Cranial cruciate ligament tear/rupture

Answer 6

No sex, age or breed predilection, but more common in younger large breed dogs.
Can occur from an acute or chronic injury and may have a partial or complete tear. Most common cause of secondary OA. Intracapsuilar soft tissue swelling, thickening of the medial joint capsule, enthesopathy at the insertion of the cranial cruciate ligament, may see avulsion fragment or tibia cranial displacement.

Question 7

Biceps tendinopathy

Answer 7

No sex or age predilection, but more common in middle aged, large breed dogs. Patients present for chronic, intermittent weight-bearing front limb lameness. Pain on manipulation of scapulohumeral joint and palpation of biceps tendon. Initially no abnormalities seen unless avulsion of supraglenoid tubercle occurs. In more chronic cases, may see mineralisation (osteophytes) in the intertrabecular groove. May see focal mineralisation bodies adjacent to the greater tubercle.