Osteoarthritis

Question 1

What is osteoarthritis?

Answer 1

• Osteoarthritis is the most common arthritis affecting synovial joints worldwide
• It is an age related, dynamic reaction pattern of a joint in response to insult or injury

Question 2

What tissues/joints are mostly affected by OA?

Answer 2

• All tissues of joint are involved
• Articular cartilage is the most affected
• Commonly affects hands, weight bearing joints such as hips, knees, feet.

OA of hands

• DIP, PIP, CMC joints
• Relapsing, remitting course over a few years
• Bony swelling and cyst formation
• Reduced hand function
• Herberdens nodes at DIP joints
• Bouchards nodes at PIP joints

OA of knees

• 3 compartments (medial - most common, lateral, patellofemoral)
• Any may be affected in isolation or in combination
• Without significant trauma, evolution very slow
• Once established, often remains stable for years

Question 3

What are the 2 main pathological features of osteoarthritis?

Answer 3

• Loss of articular cartilage causing friction and inflammation
• Disordered bone repair

Question 4

Risk factors for osteoarthritis? (8)

Answer 4

Age - uncommon before 45
Gender - female preponderance, increased prev after menopause
Genetics
Obesity - increased BMI and risk of hip and knee OA (adipose tissue releases il1, TND which causes inflammation)
Occupation - manual labour associated with OA of small joints of hand, farming OA of hips, footballers OA of knees
Local trauma
Inflammatory arthritis increases risk of OA - common to have both
Joint hypermobility, congenital hip dysplasia, neuropathic conditions

Question 5

Symptoms of OA

Answer 5

• localised disease often hip or knee
• pain & crepitus on movement
• functional impairment (walking or daily activities), worse pain with prolonged activities as joints ‘gel’
• nodal OA, joint tenderness, derangement and bony swellings (Heberden’s DIP and Bouchard’s at PIP)
• perceived lack of strength on joint due to pain

Question 6

Signs of OA & radiological features (LOSSA)*

Answer 6

Joint swelling
- bony enlargements, effusion, synovitis
Alteration in gait
Limited range of motion
Crepitus
Tenderness
Deformities

Radiological features**

• Loss of joint space
• Osteophyte formation
• Subarticular sclerosis
• Subcondral cysts
• Abnormalities of bone contour

Question 7

Management of OA
Core treatments
Non pharmacological
Pharmacological
Surgery

Answer 7

Core treatments

• exercise to improve local muscle strength
• weight loss if needed

Non-pharmacological

• MDT approach physios and occy health
• heat or cold packs
• patient education
• weight loss and exercise
• foot wear
• walking aids - sticks unload hips by 60%, frame
• stretching or manipulation

Pharmacological
- Topical NSAIDs (diclofenac gel)
- Topical Capsaicin
- Oral paracetamol, NSAID with caution and opioids
Transdermal patches - buprenorphine lignocaine
Intra-articular steroid injection - temporary relief in severe symptoms

Surgery

• joint replacement best way to deal with severe OA and has big impact on QOL
• osteotomy
• arthroplasty (uncontrolled pain, significant limitation of function, patient age sometimes considered)