Osteoarthritis Flashcards
Aetiology of OA
Mechanical “wear + tear”
localised loss of cartilage
remodelling of adjacent bone
associated inflammation
List 5 common RFs for OA
AGE
F > M
FH
Previous trauma of joint
Hypermobility of joint
Obesity
Typical joints affected in OA
Large weight-bearing joints (knee, hip)
Carpometacarpal joint
DIP, PIP joints
3 features of classic OA history
Pain following use, improves with rest
Unilateral Sx
No systemic upset
X-ray features of OA
Loss of joint space (affects distal joints more)
Osteophytes forming at joint margins
Subchondral sclerosis
Subchondral cysts
(LOSS)
3 risk factors for hip OA
F > M (2:1)
Obesity
DDH
Give 3 red flag features that suggest an alternate diagnosis to hip OA
Rest pain
Night pain
Morning stiffness > 2h
What tool is commonly used to assess severity of hip OA?
Oxford Hip Score
Describe investigations for hip OA
If features are typical: clinical dx
Otherwise: plain x-rays are first-line
Describe management of hip OA
Analgesia PO
Intra-articular injections (short-term benefit)
Total hip replacement remains the definitive Tx
List 4 peri-operative complications of total hip replacement
VTE
Intraoperative fracture
Nerve injury
Surgical site infection
What reduces risk of VTE post total hip replacement?
LMWH for 4w following op
List 4 post-op complications of total hip replacement
Leg length discrepancy
Posterior dislocation
Aseptic loosening
Prosthetic joint infection
Describe posterior dislocation of a total hip replacement
May occur during extremes of hip flexion
Presents acutely with a ‘clunk’, pain + inability to weight bear
OE: internal rotation + shortening of the affected leg
Post-hip replacement, what advice is given to reduce risk of dislocation?
Avoid flexing hip > 90 degrees
Avoid low chairs
Do not cross your legs
Sleep on back for the first 6w
What is the most common reason for revision of a total hip replacement?
Aseptic loosening
2 Risk factors for hand OA
F > M (3:1)
Occupation e.g. cotton workers + farmers
How is hand OA most commonly detected?
Radiologic signs are more common than Sx
What does hand OA increased risk of?
Future hip + knee OA
Which joints of the hand are most commonly affected in OA?
1st Carpometacarpal (CMCs) +
Distal interphalangeal (DIPJs) >
Proximal interphalangeal (PIPJs)
Describe symptoms of hand OA
Intermittent joint ache. Provoked by movement + relieved by rest
Stiffness: worse after long periods inactivity (waking up), lasts a few mins
List signs of hand OA
Painless nodes
Squaring of the thumbs
Wasting of thenar muscles at base of thumb
What are the painless nodes that develop in hand OA called? What causes these?
Bouchard’s nodes: PIPJ
Heberden’s nodes: DIPJ
Result of osteophyte formation
What causes squaring of the thumbs in hand OA?
Subluxation of CMC (partial dislocation), formation of osteophytes, + remodelling of the bones.
Results in fixed adduction of thumb.
