Lame - SA joint problems Flashcards
What is degenerative joint disease also known as?
Osteoarthritis
What are the different classifications of joint disease?
Osteoarthritis
Septic arthritis
Immune mediated arthritis
Osteochondrosis
Neoplastic
Trauma
What is articular cartilage also known as?
Hyaline cartilage
What is osteoarthritis?
Degenerative disease of synovial joints
What is a simplified explanation of what happens in osteoarthritis?
Deterioration of articular cartilage and the formation of new bone at joint margins (osteophytes)
What are some secondary causes of osteoarthritis?
Congenital eg. achondroplasia (dwarfism)
Developmental eg. hip dysplasia
Acquired eg. after fractures
What is the pathogenesis of osteoarthritis?
Loss of cartilage matrix constituents and chondrocytes
Flaking and fibrillation - less smooth
Osteophytes
Synovial membrane thickening and fibrosis
What makes up the cartilage matrix?
Collagen
Glycosaminoglycans
Chondrocytes
What is the onset of osteoarthritis?
Insidious, chronic, slowly progressive
Can be acute lameness if done lots of exercise
How do you confirm the diagnosis of osteoarthritis on radiograph?
Osteophyte formation
Soft tissue swelling
Joint effusion
Subchondral sclerosis
Synoviocentesis
What changes occur to the synovial fluid in osteoarthritis?
Increase in volume, decrease in viscosity
How do you treat/manage osteoarthritis?
Exercise modulation
Weight loss
Physical therapy/hydrotherapy
Drugs - end stage OA
Surgical options
Environmental modification
What exercise should animals with osteoarthritis do? Why?
Little and often, not vigorous
Avoid inactivity - strengthen ligaments, prevent fibrosis, maintain muscle tone
Why is massage good for osteoarthritis?
Stimulates circulation
How does hydrotherapy improve osteoarthritis?
Improves range of motion
Muscle strength improves
Fitness
No high impact
What drugs can you give for end stage osteoarthritis, or if management isnt working?
NSAIDs
Corticosteroids - last resort
How do NSAIDs help osteoarthritis?
Analgesic
Catabolic - increases proteoglycan synthesis
Has GI side effects though
What are some nutraceutical drugs/chondroprotectives?
Pentosan polysulphate
Glycosaminoglycans
What benefits do nutraceutical drugs/chondroprotectives have?
Claim to stop or moderate the degenerative processes in the cartilage
Improve joint fluid
Improve healing
What are some surgical options for osteoarthritis?
Correct inciting cause to delay progression of osteoarthritis
eg. TPLO for cranial cruciate ligament rupture
Hip dysplasia - TPO (triple pelvic osteotomy)
Patella luxation
Salvage procedures
What are some salvage procedures done for osteoarthritis?
Joint replacement
Joint fusion eg. carpus
Joint removal eg. remove femoral head
How can you modify the environment for osteoarthritis?
Soft beds
Ramps or steps
Low litter tray
Feed on the floor for cats
What is the pathogenesis of septic joint disease?
Bacteria rapidly proliferate in the joint
Acute inflammatory response
Cytokine release
Cartilage loss
Erosions
What is the signalment for septic/infectious joint disease?
Cats - bites
Dogs - young large breed males but can affect all
What are the clinical signs of septic joint disease?
Acute or chronic
Painful
Effusion/swollen
Severe lameness
Single joint
How can you diagnose septic joint disease?
Radiography
Arthrocentesis
How does synovial fluid present in septic joint disease?
Less viscous
Increased volume
Darker in colour
High numbers of cells - neutrophils
How do you treat septic joint disease?
Remove infected fluid
Lavage
Antibiotics - culture
Surgical debridement
What is the prognosis of septic joint disease?
Good in acute cases with appropriate therapy
Poor in chronic cases with cartilage loss
What are the two different categories of immune mediated inflammatory joint disease?
Erosive and non erosive
What is the most common immune mediated inflammatory joint disease?
Idiopathic immune mediated polyarthritis
What does it mean to be an erosive immune mediated inflammatory joint disease?
Can see bone erosion on imaging
What is the main erosive immune mediated inflammatory joint disease?
Rheumatoid arthritis
What are some non erosive immune mediated inflammatory joint diseases?
Idiopathic immune mediated polyarthritis
Polyarthritis/polymyositis
Polyarthritis/meningitis
Vaccine/drug reactions
What is rheumatoid arthritis usually seen in? Is it common?
Small breed dogs - rare
What occurs in rheumatoid arthritis?
Erosive joint disease
Joint collapse
Crepitus and instability
Pain variable
What is idiopathic immune mediated polyarthritis?
Type III hypersensitivity reaction - immune complex deposition that affects multiple small distal limb joints
Causes stiffness and lameness in young dogs
What are the different types of idiopathic immune mediated polyarthritis?
Type I - uncomplicated
Type II - associated with remote infection eg. pyometra
Type III - Associated with GI tract disease
Type IV - associated with neoplasia
What are the clinical signs of idiopathic immune mediated polyarthritis?
Lameness of distal small joints
Pyrexia
Can migrate from joint to joint
What does idiopathic immune mediated polyarthritis look like on radiograph?
Soft tissue swelling
How do you diagnose idiopathic immune mediated polyarthritis?
Arthrocentesis of 6 joints
Increase in volume, change in colour
Lots of neutrophils - not as active as in septic arthritis though
No bacteria
How do you treat idiopathic immune mediated polyarthritis?
Treat any underlying cause
Immunosuppressive drugs - prednisolone
Azathioprine, cyclophosphamide if these dont work
Then taper down
What is the prognosis for idiopathic immune mediated polyarthritis?
Type I - cure in 50% of cases
Other half need continued medication or euthanasia
What are some examples of tumours than invade the joints?
Synovial sarcoma
Fibrosarcoma
Haemangiosarcoma
How can you tell if a tumour in the joint is an osteosarcoma or not?
Osteosarcomas dont tend to cross joints - not in multiple bones
What is the treatment for joint neoplasia?
Amputation
What predisposes dogs to osteochondrosis?
Hereditary disease - dont breed affected dogs
Multifactorial - high calorie diet
Exercise
What is the pathogenesis of osteochondrosis?
Failure of endochondral ossification resulting in a thickened area of cartilage (cartilage doesnt turn to bone)
What is osteochondritis dissecans?
When the flap of cartilage separates from the bone into the joint
What is the signalment of osteochondrosis?
Age - 4-8 months
Large/giant breeds
Cats - very rare
More in males
What are the clinical signs of osteochondrosis?
Insidious onset lameness
Chronic
Deteriorates after rest or excessive exercise
Bilateral
Reduced range of motion in the joint
Pain on manipulation
Effusions/swelling of the joint
How do you diagnose osteochondrosis?
Radiography/CT
Saucer shaped defect in the bone
Joint mice - balls of cartilage next to joint
Osteophytes
Mineralised flaps
What conservative treatment can you use to treat osteochondrosis?
Rest, NSAIDs, diet
What surgical treatment can you use to treat osteochondrosis?
Surgery - arthrotomy, arthroscopy for cartilage flap removal
Chondrectomy - remove cartilage
What are the complications of osteochondrosis surgery?
Seroma formation
Failure to remove all cartilage flap causing chronic lameness
What is the prognosis for osteochondrosis?
Better for stifle and shoulder (loose joints)
Better for smaller lesions
Worse for tighter joints eg. hock and elbow
Worse for large lesions or chronic problem
What will all dogs develop with osteochondrosis?
Osteoarthritis
Where does osteochondrosis occur in the shoulder?
Caudomedial humeral head (OCD)
Where does osteochondrosis occur in the elbow?
Medial humeral condyle (OCD)
Anconeal and coronoid process on ulna
Where does osteochondrosis occur in the carpus?
Retained cartilaginous cores on the ulna
Where does osteochondrosis occur in the stifle?
Lateral condyle of the femur
Where does osteochondrosis occur in the hock?
Medial talar ridge on the talus
What is the most common to least common joints to get osteochondrosis in in the dog?
Elbow - most common
Shoulder
Hock
Stifle - least common
