Rheumatoid Arthritis vs Osteoarthritis:

This note compares rheumatoid arthritis (RA) and osteoarthritis (OA) — two commonly confused joint diseases that appear frequently on nursing exams. Focus on the contrasts in pathophysiology, pain pattern, joint distribution, lab findings, and medication-related teaching.

Definitions

Osteoarthritis (OA): a degenerative joint disease caused by wear and tear of articular cartilage.
Rheumatoid arthritis (RA): a chronic, systemic autoimmune disease causing inflammatory destruction of synovial joints.

RA vs OA at a Glance

Feature	Rheumatoid Arthritis (RA)	Osteoarthritis (OA)
Pathophysiology	Autoimmune; synovial inflammation	Degenerative; cartilage wear and tear
Age of onset	30–50 years	>50 years
Joint involvement	Symmetrical	Asymmetrical
Joints affected	Small joints (hands, wrists, feet); cervical spine	Weight-bearing joints (hips, knees); hands (DIP, PIP, CMC)
Morning stiffness	>60 minutes, improves with activity	<30 minutes, worsens with activity
Systemic symptoms	Yes (fever, fatigue, weight loss, nodules)	No
Lab findings	RF positive, anti-CCP positive, ↑ ESR/CRP	Normal
X-ray findings	Joint erosions, soft tissue swelling, osteopenia	Joint space narrowing, osteophytes, subchondral sclerosis
Deformities	Ulnar deviation, swan neck, boutonniere	Heberden's nodes (DIP), Bouchard's nodes (PIP)

Clinical Features

Osteoarthritis (OA)

Pain worsens with activity and improves with rest.
Morning stiffness lasts less than 30 minutes.
Affects hips, knees, and distal interphalangeal (DIP) joints.
Heberden's nodes on DIP joints; Bouchard's nodes on PIP joints.
Crepitus (grating sensation) common with joint movement.
No systemic symptoms.

Rheumatoid Arthritis (RA)

Pain improves with activity and worsens with rest.
Morning stiffness lasts more than 60 minutes.
Symmetrical involvement of small joints of hands, wrists, and feet.
Deformities: ulnar deviation, swan neck, boutonniere.
Rheumatoid nodules: firm, painless lumps under the skin.
Systemic symptoms: fatigue, low-grade fever, weight loss, malaise.

Pathophysiology

OA: mechanical stress and aging cause cartilage breakdown, bone spur (osteophyte) formation, and mild secondary inflammation.
RA: autoimmune-mediated synovial inflammation forms a pannus that erodes cartilage and bone, with systemic effects.

Diagnostic Tests

Anti-CCP is the most specific test for RA.
Rheumatoid factor (RF) is positive in 70–80% of RA patients.
ESR and CRP are elevated in RA but normal in OA.
X-ray (OA): joint space narrowing, osteophytes, subchondral sclerosis.
X-ray (RA): joint erosions, soft tissue swelling, osteopenia.

Management

Osteoarthritis

First-line: weight loss and low-impact exercise.
Acetaminophen first-line for mild to moderate pain; NSAIDs for moderate to severe pain.
Topical NSAIDs or capsaicin cream for localized pain.
Intra-articular corticosteroid injections for flare-ups.
Joint replacement for severe, refractory disease.

Rheumatoid Arthritis

DMARDs first-line — methotrexate is most common.
Biologic agents (TNF inhibitors) for moderate to severe disease.
NSAIDs and corticosteroids for symptom control only.

RA Medications

Drug Class	Examples	Key Exam Points
DMARDs	Methotrexate, Hydroxychloroquine	Methotrexate: monitor LFTs and CBC, give folic acid, teratogenic
Biologic DMARDs (TNF inhibitors)	Etanercept, Adalimumab, Infliximab	Screen for TB before starting; no live vaccines
Corticosteroids	Prednisone	Short-term use for flares only
NSAIDs	Ibuprofen, Naproxen	Monitor for GI bleeding and renal impairment

Nursing Interventions

Apply heat (paraffin, warm packs) for morning stiffness in both conditions.
Apply cold packs for acute inflammation and pain.
Encourage low-impact exercise (walking, swimming).
Teach joint protection: use large joints, avoid repetitive motions.
Provide assistive devices (jar openers, reachers, built-up handles).
For RA: monitor for signs of infection due to immunosuppression.
Ensure TB screening before initiating TNF inhibitors.

Patient Teaching

Take medications as prescribed; do not stop DMARDs or biologics abruptly.
Apply heat before activity to reduce stiffness.
Apply cold after activity to reduce pain and swelling.
For OA: use joint protection techniques and maintain a healthy weight.
For RA: report signs of infection and avoid live vaccines while on biologics.

Common Exam Traps

RA pain improves with activity; OA pain worsens with activity.
RA is symmetrical; OA is asymmetrical.
Heberden's (DIP) and Bouchard's (PIP) nodes are specific to OA.
Ulnar deviation and swan neck deformity are specific to RA.
Anti-CCP is the most specific test for RA.
Methotrexate requires folic acid supplementation and LFT monitoring.
TNF inhibitors require TB screening before initiation.

Key takeaways

OA = degenerative, asymmetrical, weight-bearing joints, stiffness <30 min, worse with activity, no systemic symptoms.
RA = autoimmune, symmetrical, small joints, stiffness >60 min, better with activity, systemic symptoms present.
Anti-CCP is the most specific lab for RA; ESR/CRP are elevated. OA labs are normal.
Methotrexate is first-line for RA — monitor LFTs/CBC, give folic acid, and avoid in pregnancy.
Screen for TB and avoid live vaccines before starting TNF inhibitors.
Nursing care for both: heat before activity, cold after activity, joint protection, and low-impact exercise.

Rheumatoid Arthritis vs Osteoarthritis: Nursing Study Guide