Joint disease part 1 Flashcards
(29 cards)
What is the makeup of cartilage
5% chondrocytes
95% Extra cellular matrix
no blood vessels or nerves
What makes up extra cellular matrix
Water, proteoglycans, collagen network
What are the four qualities of cartilage and what are they for
Smooth surface: for gliding
Sufficient elasticity: shock absorbing
Sufficient stiffness: to transfer loads
Sufficient strength: to prevent damage
Why does cartilage have poor regenerative ability
-Avascular nature
-Adult chondrocytes do not replicate or migrate
What are clinical signs and radiographic findings of osteoarthritis
-Clin signs: lameness, pain, stiffening, joint effusion, soft tissue swelling, reduced range of motion, positive flexion test
-Radiographic findings: osteophytes, increased bone formation, osteolysis, cysts, bone sclerosis, reduced joint space
Why is there pain if there is no nerve supply to cartilage
-Pain due to: Inflammation of synovial membrane/joint capsule, increased intra-articular pressure, bone irritation
What is the general principle of the treatment of osteoarthritis
-If present, eliminate primary cause, break through vicious circle and reduce inflammatory part and stop ongoing damage
What are 4 nonsurgical treatments of osteoarthritis
1) exercise regime
2) hoofcare/orthopedic shoeing
3) physical techniques
4) medications
What are some options under exercise regime for treating OA
-Box rest
-Uncontrolled exercise
-Controlled exercise
-Specific training/ rehab
-Physiotherapy
What are some options for hoofcare/ortho shoeing for treating OA
-Foot axis/ hoof balance
-Shock absorbing (hoof pads)
-Pressure distribution/loading
-Ortho shoeing
What are some physical therapies for treating OA
-Hydrotherapy
-Thermotherapy
-Extracorporeal shockwave therapy
-Magnetic field therapy
What are some options for medication for treating OA
-NSAIDs
-Corticosteroids (locally at level of joint)
-Disease modifying OA drugs(chondromodulating/ chondprorotectives)
-Cell based therapies
-Others like Tildren DMSO Orthokin)
What is the pathogenesis of septic arthritis
-Bacteria easily colonize joint if able to enter due to very little defense (few WBCs, synovium rich in blood)
-Causes potent inflammatory response, release of toxins/cytokines, macrophages attracted, lysosomal enzymes released
-Further tissue damage leads to destruction of cartilage, capsule, bone damage
What are the most common etiologies of septic arthritis
-Traumatic wounds most common
-Joint infections followed by joint surgery and idiopathic causes
-In foals, usually hematogenous spread
What are the most common bacterial agents in septic arthritis
-91% aerobic or facultative anaerobes
-28% Enterobacteriaceae
-13% strep 11.8% staph
-mixed infections common with traumatic wounds
-staph and strep common with post injection or post surgical infections
-foals: enterbacteriaceae most common typically from umbilicus
What are the three types of septic arthritis in foals
-S type infections: synovial membrane and fluid only involved, usually < 1 week
-E type infections: bone adjacent to articular cartilage involved, older foals (weeks old)
-P type infections: primary infection of long bone physics, +/- joint involvement, extension into joint usually at level of joint capsule, foals weeks to months old
What clinical signs are seen with septic arthritis and what are diagnostic options
-Joint effusion and heat, fever (rare in adults), lameness
-Diagnostics: history, clin signs, arthrocentesis (synovial fluid interpretation), rads/US, wound evaluation
What does normal synovial fluid look like
-Translucent, pale yellow
-Viscous
-Sterile
-10-20g total protein/L
-WBCs: total .2-2x10^9/L, mainly lymphocytes and large mononuclear cells
What changes in synovial fluid would be expected with diseased joints
-Increased volume (joint effusion)
-decreased viscosity
-Appearance: cloudy/turbid/amber if septic, hemorrhagic if traumatic
-Total protein: >40 g/L in septic arthritis
-WBCs: >20x10^9/L, >90% PMNs (mostly neutrophils) in septic arthritis, toxic neutrophils indicative of infection
How quickly will you see radiographic changes in a foal and adult horse with arthritis
-Foals: less than 1 week
-Adults: 10-12 days
What are treatment options of septic arthritis
-Drainage and lavage
-Antibiotics: selection/delivery methods important
-Antiinflammatories and analgesics
How to perform needle lavage of a septic arthritic joint
-Sterile balanced electrolyte solution (LRS)
-Sedated or anesthetized
-18G or 16 G needles
-2-3 L on a pressure bag
What are the benefits of arthroscopic lavage
-Allows rapid delivery of fluids
-Facilitates removal of fibrin clots
-Debridement of any unstable cartilage or bone
-Direct evaluation of the condition of the joint surfaces
What types of antibiotics should be used to treat septic arthritis
-Broad spectrum until sensitivity results
-Penicillin an aminoglycosides (gentamicin and amikacin, good penetration)
-combine systemic and local administration
