Osteoarthritis (OA) Treatment

Non-Pharmacologic Treatment (First-Line)

Pharmacologic Treatment

1. Acetaminophen (Paracetamol)

• Treatment effect is small and not considered clinically meaningful overall
• For a minority of patients, it is adequate to control symptoms, allowing avoidance of more toxic drugs
• Max dose: up to 2 g/day (Harrison's, p. 2998)
• Status: conditionally recommended (ACR guidelines)

2. NSAIDs and COX-2 Inhibitors (Most Popular)

• Slightly less efficacious than oral agents, but far fewer GI/systemic side effects
• Plasma concentrations one order of magnitude lower than oral route
• Drug reaches synovium and cartilage of superficial joints (knees, hands - not hips)
• AAOS: Strong recommendation for both topical and oral NSAIDs
• Side effect: local skin irritation (redness, burning, itching)

• GI toxicity: dyspepsia, nausea, GI bleeding, ulcer disease - add PPI for high-risk patients (age ≥60, prior GI events, glucocorticoid use)
• Cardiovascular: diclofenac and most NSAIDs increase MI/stroke risk; naproxen is the safest from a cardiovascular standpoint; low-dose celecoxib (≤200 mg/day) does not significantly elevate risk
• Renal: avoid in stage 3-5 CKD; can cause edema and reversible renal insufficiency
• Drug interaction: take low-dose aspirin at different times from ibuprofen/naproxen
• (Harrison's, p. 2998-2999)

3. Intraarticular Injections

• AAOS: Moderate recommendation for short-term relief
• Provide efficacy for up to 3 months; response is variable
• Useful for acute flares of pain
• Repeated injections may cause minor cartilage loss, but do not appear to worsen disease progression or increase surgical need
• Greater contextual (placebo) effect than oral medications

• AAOS: Not recommended (moderate evidence against)
• Most evidence suggests little efficacy versus placebo for knee/hip OA
• (Harrison's, p. 2999)

• AAOS: Limited evidence (2-star)
• A 2025 meta-analysis of RCTs (PMID: 39751394) found clinically significant improvement in knee OA, with effect size influenced by platelet concentration - not yet guideline-endorsed but emerging evidence is promising

• Few rigorous studies; composition not standardized; not recommended in current guidelines

4. Duloxetine

• FDA-approved for OA
• Useful when NSAIDs are ineffective
• Particularly efficacious when knee pain is part of a widespread pain syndrome

5. Opioids

• Not recommended (AAOS strong) - only modest short-term efficacy, no long-term benefit, dependency risk, less effective than oral NSAIDs
• Tramadol is also not recommended in this context

6. Other Agents

• Glucosamine / Chondroitin: Not recommended per current guidelines; large trials show no benefit over placebo
• Curcumin: Has anti-inflammatory properties; may alleviate pain; evidence emerging
• GLP-1 receptor agonists: A large RCT showed reduction in knee pain in obese patients - an emerging avenue
• Methotrexate / Prednisolone: Shown to reduce hand OA pain in specific RCTs; not standard for knee/hip OA
• Doxycycline: Studied for OA (MMP inhibition), but not in standard use
• Vitamin D, turmeric, ginger extract: Limited evidence (AAOS 2-star)

Surgical Treatment

Arthroscopy

• Arthroscopic debridement and lavage: NOT recommended - efficacy no greater than sham surgery in RCTs
• Arthroscopic meniscectomy for meniscal tears + mild-moderate OA: Moderate AAOS recommendation - but long-term benefit for pain/function is not supported by RCT evidence

Osteotomy

• High tibial osteotomy - for isolated medial compartment knee OA; realigns load to lateral compartment; provides years of relief before total knee replacement is needed
• Unicompartmental replacement with realignment - alternative to osteotomy
• AAOS: Limited evidence (2-star); useful in properly selected patients

Total Joint Arthroplasty

• Indicated when nonsurgical treatment has failed with unacceptable pain/disability affecting quality of life
• Total hip replacement: Relieves pain in almost all patients
• Total knee replacement: Pain relief in ~80% of patients
• Failure rate (loosening/infection): ~1% per year (higher in obese patients)
• Better outcomes in centers performing ≥25 operations per year
• Timing matters: operating too late (after severe functional decline and muscle wasting) limits postoperative recovery

Cartilage Regeneration

• Chondrocyte transplantation and abrasion arthroplasty (chondroplasty) - not well-established for OA; more likely to benefit early-stage disease
• (Harrison's 22E, p. 2999-3000)

Summary: Stepwise Approach

Step 1 - Foundational (all patients):
  Education, exercise, weight loss, physiotherapy

Step 2 - Pharmacologic:
  Topical NSAIDs → Oral NSAIDs (with GI/CV risk assessment)
  ± Acetaminophen (prn) ± Duloxetine (if widespread pain)
  Intraarticular corticosteroids for acute flares

Step 3 - For refractory symptoms:
  Assess for osteotomy (young, unicompartmental disease)
  Consider PRP (emerging evidence)

Step 4 - End-stage:
  Total joint arthroplasty (knee or hip)

• Harrison's Principles of Internal Medicine 22E (2025), Chapter 383, pp. 2998-3000
• Miller's Review of Orthopaedics 9E - AAOS Knee OA CPG Table 5.7
• 2021 AAOS Management of Knee OA Guideline
• 2019 ACR/Arthritis Foundation OA Guidelines
• Exercise for knee OA: Cochrane Review 2024 (PMID: 39625083)
• PRP for knee OA: Meta-analysis AJSM 2025 (PMID: 39751394)