Osteoarthritis Flashcards
epidemiology, pathophysiology, presentation, investigation, management and prognosis
Is the onset of OA gradual or rapid, and from what age does OA onset begin?
Gradual onset from age 40
Between what ages does OA incidence increase rapidly?
50-75
What percentage of individuals with OA have limited mobility?
80%
What percentage of individuals with OA have difficulty performing daily lifestyle activities?
25%
Is prevalence and risk of OA higher in men or women?
Women
How does change in composition of the articular cartilage due to OA affect it’s susceptibility to physical forces?
Becomes more susceptible to disruption by physical forces, which is why mechanical stress causes joint degeneration
How much of a joint does OA degenerate?
Entire joint
What cells cause articular cartilage to degrade and reveal underlying bone in OA, and what do they release to cause degradation?
Chondrocytes in areas of stress, that proliferate and release inflammatory mediators that degrade cartilage matrix
After the articular cartilage degrades and underlying subchondral bone is revealed in OA, how does new articular cartilage form?
Underlying subchondral bone becomes the new articular cartilage
In the process of articular cartilage degeneration and underlying subchondral bone becoming the new articular cartilage, how does this affect the joint space in OA?
Causes joint space narrowing
How does subchondral sclerosis occur in OA?
Mechanical stress on underlying subchondral bone (that has become new articular cartilage) grows and hardens
How do osteophytes form from the new articular cartilage in OA?
Local bony areas grow into outgrowths/protrusions
What factors are released in OA that result in pain and inflammation, and how do the factors stimulate this?
Vascular growth factors stimulate neurovascular development, which causes pain and inflammation in the joint
How do bone cysts form in OA?
They form in areas of localised bone necrosis and resorption, which occurs due to stress-induced microfractures in subchondral bone
What is subchondral bone?
Bone beneath articular hyaline cartilage
How does OA affect the synovial lining, and what is the name of this condition?
Synovitis: inflammation and thickening of synovial lining
What is the name of swelling that occurs in OA?
Joint effusion
What is the difference between primary OA and secondary OA?
Primary OA arises from non-specific/idiopathic cause
Secondary OA arises from another specific cause
Give 3 examples of causes that can lead to secondary OA onset?
Trauma, RA, infection
Does OA present in the same way in every joint?
No, presentation of OA depends on type of affected joint
What aspect of the knee is affected by OA, and what is the resulting deformity?
Affects weight-bearing inner aspect which narrows joint space, so results in varus deformity, characterised by bow-legged look
When does pain occur due to knee OA, and how does it change throughout the day?
Activity-related pain that is worst at night and is relieved by morning due to rest
Is elbow OA common in primary or secondary OA?
No, it is rare
What 4 movements are painful due to elbow OA?
Elbow flexion, extension, supination, pronation
What 3 places can pain arise in due to hip OA?
Thigh, buttocks, groin
What 2 activities are difficult due to hip OA?
Walking up and down stairs
Putting on shoes
What are 2 characteristic features of hand OA?
Heberden’s nodes form when osteophytes grow at distal interphalangeal joints
Base of thumb is square-shaped
What condition can severe development of shoulder OA lead to, that affects the shoulder joint stability and movement?
Rotator cuff tear arthropathy, due to OA causing loss of function in rotator cuff
What are the 2 ways in which rotator cuff tear arthropathy is managed?
Total anatomical replacement of rotator cuff
Reverse anatomical replacement, so that deltoid moves and positions arm instead
Why do OA patients commonly present with disuse atrophy?
Pain has gradual onset and is worsened by movement, so patients avoid movement which causes muscle wasting
What 4 X-ray features indicate OA?
Osteophytes
subchondral cysts
narrowed joint space
subchondral sclerosis
Is a blood test necessary to diagnose OA?
No, but is useful to exclude differential diagnoses eg. RA, PsA, gout
What is the focus of OA management?
Changing lifestyle
Why is a long-term physiotherapy plan and exercise implemented for OA management?
To maintain physical function and decrease further degeneration
What 2 types of exercise must be included in physiotherapy for OA management?
Local muscle strengthening
General aerobic exercise
What shoes are beneficial for individuals with knee and hip OA?
Shoes with thick, shock-absorbing soles and no raised heels
Give 3 examples of physical aids that are useful to individuals with hip and knee OA?
Walking sticks
Walking frames
Wheeled walkers
Why is occupational therapy useful for individuals with OA?
They add home modifications that can make it easier for individuals to complete daily activities despite limited mobility eg. handrails on stairs
Why are medicines used in OA management?
Adjunct (supplementary) alongside core physical management, used for symptomatic relief eg. pain, inflammation
What are the 2 first-line therapies for OA management?
Topical NSAIDs
Paracetamol monotherapy
If topical NSAIDs and/or paracetamol provide insufficient/no symptomatic relief for OA, what medication can be used?
Oral NSAIDs, which can be used in combination with paracetamol
If oral NSAIDs are contraindicated in OA management, what medication can be used?
Opioid analgesics, which can be used in combination with paracetamol
What medication is beneficial for providing symptomatic relief in hand and knee OA, and when can it be used?
Topical capsaicin can be used in any stage of treatment
Why are intra-articular corticosteroid injections provided in OA?
Moderate-severe pain relief caused by inflammation and swelling
When is orthopaedic surgery required in OA management?
Severe joint deterioration, and before there is prolonged and established functional limitation and severe pain
Are patient-specific factors such as gender, smoking, obesity barriers to referral for orthopaedic surgery?
No
What are the 3 requirements to clinically diagnose OA with no other investigations, according to NICE guidelines?
45y or over
Activity-related joint pain
Either no morning joint-related stiffness, or morning stiffness that lasts no longer than 30 minutes
If an obese/overweight person has OA, what intervention is recommended by NICE?
Intervention to encourage weight loss
What is arthrodesis surgery?
Any diseased cartilage between two bones is removed and the bone ends are cut off, and connected to another using metal internal fixation, such as screws and plates, then eventually grow into one another and fuse to become one bone
What are 2 benefits of arthrodesis?
Durable, provides pain relief
What is the disadvantage of arthrodesis?
Need to sacrifice some movement
What is the main difference between arthrodesis and arthroplasty?
Arthrodesis causes fusion within the joint
Arthroplasty causes replacement within the joint
Give 3 examples of types of arthroplastys?
Excision arthroplasty
Hemiarthroplasty (replacing half of hip/only femoral head)
Total joint arthroplasty (replaces all parts of joint/eg. Femoral head and acetabulum)
Give 1 benefit and disadvantage of an arthroplasty?
Keep range of movement
Not durable and wears over time
What is a trapeziectomy?
Form of excision arthroplasty where trapezium bone at base of thumb is removed, treats thumb base OA and squaring
Give 2 benefits and disadvantages of a trapeziectomy?
Durable and preserves range of movement
Can cause carpal instability and has long rehab period
What is the main factor in deciding whether you should fuse or replace a joint?
The range of motor function in that joint eg. in a joint that is used for a lot of flexion should be replaced
Give immediate, early and late complications of an arthroplasty?
Immediate: technical eg. perioperative fracture
Early: infection, dislocation (could be constrained or unconstrained)
Late: aseptic loosening (bone implant interface), wearing over time
Give 2 functions for regular reviews of individuals with symptomatic OA?
Monitor long-term course of OA
Review effectiveness and tolerability of treatments for OA
What are the 3 conditions that if an individual has one or more, they have annual reviews of their OA?
Other illnesses or conditions
Troublesome joint pain, more than one joint affected
Taking any drugs for their osteoarthritis
