Osteoarthritis vs Psoriatic Arthritis
Osteoarthritis and Psoriatic Arthritis are easy to mix up on the boards. Here's a side-by-side comparison — presentation, workup, imaging, and first-line treatment — drawn from our full outlines.
Osteoarthritis vs Psoriatic Arthritis at a glance
- Osteoarthritis: Non-inflammatory degenerative joint disease driven by progressive articular cartilage loss.
- Psoriatic Arthritis: Seronegative inflammatory arthritis associated with psoriasis; classic features include dactylitis, enthesitis, and DIP involvement.
Keep comparing — start your free trial
You've used your 2 free previews. Create your free account to see the full Osteoarthritis vs Psoriatic Arthritis comparison — plus all 514 diagnosis outlines, 5,500+ board-style questions, and an AI tutor. Your 7-day free trial includes everything, no credit card required.
Side-by-side comparison
| Feature | Osteoarthritis | Psoriatic Arthritis |
|---|---|---|
| At a glance | Non-inflammatory degenerative joint disease driven by progressive articular cartilage loss. | Seronegative inflammatory arthritis associated with psoriasis; classic features include dactylitis, enthesitis, and DIP involvement. |
| Classic presentation | Heberden nodes (DIP) and Bouchard nodes (PIP); squared first CMC joint; medial knee joint-line tenderness.; Insidious joint pain worse with activity and… | Joint pain with morning stiffness >30 minutes, improving with activity; Asymmetric oligoarthritis (most common pattern), DIP-predominant, polyarticular… |
| Workup / key labs | ACR clinical criteria for knee OA: knee pain plus at least 3 of: age >50, stiffness <30 min, crepitus, bony tenderness, bony enlargement, no palpable warmth.… | CASPAR classification criteria: inflammatory articular disease (joint, spine, or entheseal) plus ≥3 points from psoriasis, nail changes, RF-negative,… |
| Imaging | Weight-bearing plain radiographs of the affected joint — first-line; MRI reserved for atypical presentations, suspected meniscal or ligamentous injury, or… | Plain radiographs — 'pencil-in-cup' deformity at DIPs, periostitis, fluffy new bone formation, marginal erosions, ankylosis, asymmetric sacroiliitis,… |
| First-line treatment | Patient education and self-management programs; Exercise: low-impact aerobic, strengthening (quadriceps for knee OA), aquatic therapy; Weight loss (5-10% body… | Mild peripheral disease: NSAIDs — naproxen, ibuprofen, meloxicam — plus intra-articular steroid injections; Conventional DMARDs for peripheral arthritis:… |
Drill Osteoarthritis vs Psoriatic Arthritis questions on FirstPassPA
Turn this comparison into retention. 5,500+ board-style questions with an AI tutor that explains every answer — free to start, no card required.
Start studying free → Try today's free questionEducational use only. This outline is a study aid for PA students and is not medical advice or a substitute for clinical judgment. FirstPassPA is an independent study tool and is not affiliated with, endorsed by, or sponsored by NCCPA. PANCE® and PANRE® are registered trademarks of the National Commission on Certification of Physician Assistants.