What are the diagnostic criteria and management options for osteoarthritis?

Diagnostic Criteria for Osteoarthritis

Osteoarthritis diagnosis is primarily clinical, based on joint pain worsened by movement in patients over 40 years old, with radiographic confirmation showing osteophytes providing 83% sensitivity and 93% specificity when combined with knee pain. 1, 2

Clinical Diagnostic Features

Core Clinical Criteria

• Pain on joint usage that worsens with movement and improves with rest 3, 2
• Age over 40 years (likelihood ratio 3.73,95% CI 2.69-5.18) 3
• Minimal morning stiffness (typically less than 30 minutes) or only mild inactivity stiffness 4
• Functional impairment in activities of daily living that can be as severe as rheumatoid arthritis 3, 4

Hand OA Specific Features

• Heberden nodes (posterolateral firm/hard swellings at distal interphalangeal joints) increase probability of hand OA from 20% alone to 88% when combined with age >40, family history, and radiographic joint space narrowing 3
• Bouchard nodes (posterolateral firm/hard swellings at proximal interphalangeal joints) 3
• Characteristic joint distribution: DIP joints, PIP joints, thumb base (CMC joint), and index/middle MCP joints 3, 4
• Bilateral symmetrical pattern is common 4

Risk Factors That Support Diagnosis

• Female sex (RR 1.23,95% CI 1.11-1.34) 3
• First-degree family history (OR 2.57,95% CI 1.86-3.55) 3
• Obesity (BMI >29: OR 8.3,95% CI 1.2-56.5) 3
• History of joint injury (OR 3.64,95% CI 1.34-9.88) 3
• Occupational factors including repetitive joint use, heavy lifting, or high-impact activities 3

Radiographic Criteria

Essential Radiographic Features

• Osteophytes are the single best radiographic feature to differentiate OA from other conditions 1, 5
• Asymmetric joint space narrowing 6
• Subchondral sclerosis 6
• Subluxation in advanced disease 6

Hand OA Radiographic Patterns

• Joint space narrowing in finger joints combined with clinical nodes dramatically increases diagnostic probability 3
• Distinctive intercarpal and carpometacarpal pattern occurs in 41% of hand OA patients, bilateral in 69% of cases 7
• Subchondral erosions with cortical destruction define erosive OA subset 3

Diagnostic Algorithm

No single test defines OA alone (likelihood ratio <10), but composite assessment greatly increases diagnostic accuracy: 3

1. Clinical assessment: Pain on movement + age >40 + characteristic joint involvement
2. Physical examination: Presence of Heberden/Bouchard nodes, bony enlargement, joint tenderness
3. Radiographic confirmation: Osteophytes ± joint space narrowing
4. Laboratory testing: NOT required for diagnosis but may exclude inflammatory arthritis if marked inflammatory signs present 4

---

Management of Osteoarthritis

Non-Pharmacological Management (First-Line)

Education and Self-Management

• Patient education on disease nature, course, and self-management principles should be provided to all patients 8
• Joint protection techniques to minimize stress on affected joints 8
• Assistive devices for activities of daily living 8

Exercise and Physical Therapy

• Exercise programs including range of motion and strengthening exercises reduce pain and disability 3, 8
• Physical therapy should be offered as part of comprehensive management for hip and knee OA 3
• For hip OA: Either formal PT or unsupervised home exercise after total hip arthroplasty (moderate-strength recommendation based on high-quality evidence) 3
• For hand OA: Exercises specifically targeting joint mobility, muscle strength, and thumb base stability 8

Weight Management

• Weight loss for patients who are overweight or obese (BMI reduction improves outcomes) 3

Orthoses and Splinting

• For thumb base (CMC) OA: Custom-made neoprene or rigid orthoses used for at least 3 months provide optimal symptom relief 8, 7
• For knee OA: Soft braces may be beneficial 3
• For other hand joints: Orthoses may be considered as disease progresses 8

Thermal Modalities

• Heat application (paraffin wax, hot packs) especially before exercise provides symptomatic relief (77% recommendation strength) 8

Pharmacological Management

Topical Treatments (Preferred First-Line)

• Topical NSAIDs are first-line pharmacological treatment, especially for hand OA and when few joints affected 8, 7
• Topical capsaicin may be considered as alternative 8
• Safety advantage: Preferred over systemic treatments, particularly in patients ≥75 years 8

Oral Analgesics

Step-wise approach: 8, 2

1. Acetaminophen (paracetamol) up to 4g/day is first-choice oral analgesic due to efficacy and safety profile 8

2. Oral NSAIDs at lowest effective dose for shortest duration when acetaminophen insufficient 8, 9

   • For patients ≥75 years: topical NSAIDs preferred over oral 8
   • For increased GI risk: non-selective NSAID + gastroprotective agent OR selective COX-2 inhibitor 8
   • Naproxen 375-750mg twice daily shown effective for OA with less GI toxicity than aspirin 9

3. Duloxetine for chronic pain due to OA (60mg daily showed significant pain reduction in knee OA) 3, 10

4. Tramadol for inadequate response to other analgesics 8

Intra-Articular Injections

• Corticosteroid injections for painful flares, especially effective for trapeziometacarpal (thumb base) joint (provides 4-8 weeks relief) 3, 8
• Hyaluronic acid injections for knee OA (more expensive but longer symptom improvement than corticosteroids) 3, 2

Treatments NOT Recommended

• Opioids: Initiation not suggested for OA 3
• Disease-modifying antirheumatic drugs (conventional or biological): Should NOT be used 8
• Combination with aspirin: Not recommended due to increased NSAID excretion and higher adverse event frequency 9

Surgical Management

Indications

• Severe pain and/or disability despite maximal conservative treatment 8, 2
• For thumb base OA: Interposition arthroplasty, osteotomy, or arthrodesis 8, 7
• For hip/knee OA: Total joint replacement for chronic pain and disability despite maximal medical therapy 2

Perioperative Considerations for Hip OA

• Neuraxial anesthesia recommended 3
• Tranexamic acid (TXA) administration to reduce blood loss 3
• Cemented femoral fixation should be considered in older patients to reduce periprosthetic fracture risk (moderate-strength recommendation) 3

Treatment Algorithm for Hand OA

First-line: 8

• CMC joint orthosis (custom-made, ≥3 months)
• Joint protection education
• Exercise program
• Topical NSAIDs
• Heat therapy before exercises

Second-line: 8

• Add acetaminophen up to 4g/day

Third-line: 8

• Short-term oral NSAIDs (lowest effective dose)
• Intra-articular corticosteroid injection for painful flares (especially CMC joint)

Surgical referral: 8

• When conservative treatments fail in severe thumb base OA with marked pain/disability

Common Pitfalls

• Underestimating functional impact: Hand OA disability can equal rheumatoid arthritis severity 4
• Inadequate splinting duration: Splints must be used consistently for at least 3 months to show benefit 8
• Long-term oral NSAID use: Avoid due to GI, cardiovascular, and renal risks 8
• Failing to assess for generalized OA: Patients with polyarticular hand OA have 2.4 times increased risk of knee OA and should be assessed for OA at other sites 3, 4
• Not recognizing OA subsets: Erosive OA, nodal OA, and thumb base OA may require different management approaches 3, 4
• Premature optimization expectations: For hip OA surgery, patients should optimize BMI, HbA1c <7.3%, discontinue narcotics, and quit smoking before surgery to reduce adverse events 3