osteoarthritis (Steve Darby) Flashcards
(51 cards)
What is osteoarthritis?
degenerative disease
characterised by the progressive degeneration, destruction and erosion of articular cartilage
bone ends rub together
difference between OA and RA
OA is a degenerative disease -> RA is an autoimmune disease OA inflammation is minimal -> RA has imflammed synovial membrane OA is erosion of cartilage -> RA erosion of bone OA bone ends rub together -> RA they don't OA asymmetrical -> RA symmetrical
When is stiffness with OA?
morning stiffness lasting less than 30mins
joints most affected
knee
hip
hand/wrist
risk factors for OA
occupation (coal miners, golfers, footballers, rugby) bending of the knee kneeling squatting standing for long hrs (>2 per day) walking >3km per day regular stair climbing heavy lifting vibration
What chromosome is important for genetic linkage of OA?
chromosome 2q13-32
- includes the IL-1 gene cluster
- frizzles related protein (FRZB)
- cartilage structural protein matrilin-3 (MATN3)
What happens in early stages of OA?
cartilage develops irregularities at the surface where it becomes fibrillated
What happens as OA progresses?
- deep clefts form in cartilage
- loss aggrecan and type II collagen within the cartilage extracellular matrix (structural proteins)
- chondrocytes clump within cartilage surrounded by regions of intense staining material indicating increased proteoglycan
- ongoing cartilage damage, articular joint surface damaged, loss of joint fxn
MMPs
matrix metallo proteases
What leads to MMP production?
- increased mechanical insult (yrs of damage)
- chondrocytes release cytokines (IL1, TNF alpha)
- increases MMP production
What do MMPs do?
degrading enzymes
- breakdown extracellular matrix in tissues
- collagen destruction
- synovial cell irritation
Where do cartilage breakdown products go?
into synovial fluid
synovial cells ingest the breakdown products
What do synovial cells release?
proteinases and proinflammatory cytokines
these upregulate catabolic processes in synovial membrane and cartilage
What structural proteins are broken down in the cartilage?
collagen
proteoglycan
What are osteophytes?
bony spurs formed in OA
can limit space in the joint
pinch nerves
Where can osteophytes occur?
neck shoulder knee lower back fingers big toe foot/heel
OA symptoms
- clicking/cracking sounds in joints
- slow onset of symptoms
- mild swelling
- asymmetry
- stiffness
- pain in a joint (hip/knee/hands most common)
- bone spurs
- reduced flexibility (bending/stairs)
OA diagnosis
medical Hx
physical examination
x-ray/MRI
fluid aspiration (oculd be joint infection, crystals-gout)
primary OA
- no known cause (onset over time)
- idiopathic OA
- elderly
- most common
secondary OA
- linked to an existing disease (gout, haemochronatosis)
- congenital abnormality
- hormonal/inflammatory disorder (Acromegaly/Paget’s)
- joint injuries (not repaired correctly)
- younger patients
- less common
What approach is used for management of OA?
combined approach of
- non-pharmacological
- pharmacological
non-pharmacological management
exercise and manual therapy joint aids/supports TENS surgical joint replacement and arthroscopic lavage nutraceuticals
pharmacological management
- paracetamol
- NSAIDs
- capsaicin
- corticosteroids
- DMOADs (not on market)
main non-pharmacological management
weight loss - aerobic exercise - low impact - swimming/yoga muscle strengthening - joints - ligaments/tendons - stretching/physiotherapy
