In an overweight adult with osteoarthritis who stands or walks for many hours, how should I evaluate knee pain that may be related to inappropriate footwear and what management steps should I take?

Evaluating Knee Pain and Footwear in Overweight Adults with Osteoarthritis

Recommend stable, supportive shoes with shock-absorbing properties and adequate toe space, while simultaneously addressing weight loss and exercise as core treatments for this patient's knee osteoarthritis. 1

Footwear Evaluation

What to Look For in Current Shoes

• Assess heel height: Elevated heels increase knee joint loading by approximately 15% compared to flat shoes 2
• Check flexibility: Rigid, inflexible shoes (like clogs and stability shoes) significantly increase peak knee adduction moment by ~15% compared to flat, flexible footwear 2
• Evaluate shock absorption: Shoes lacking cushioning properties fail to reduce impact forces on already compromised knee joints 1
• Measure fit: Nearly 50% of women and 70% of men wear incorrectly sized shoes (typically too large), which is associated with larger foot dimensions and ankle pain 3
• Examine toe box space: Shoes must provide ample space for toes when weight-bearing to prevent biomechanical compensation 1

Recommended Footwear Characteristics

The 2024 EULAR guidelines provide the most current evidence-based footwear recommendations: 1

• Stable, supportive shoes worn ≥6 hours daily show small but significant pain reduction at 6 months (though not function improvement) 1
• Flat, flexible shoes produce knee loads equivalent to barefoot walking and are preferable to elevated or rigid footwear 2
• Shock-absorbing insoles for 1 month reduced pain and improved physical function in knee OA patients 1
• Comfortable fit with adequate toe space during weight-bearing is a general clinical recommendation despite limited trial evidence 1

What NOT to Recommend

• Lateral wedge insoles: Most evidence does not support their use for pain or function improvement in knee OA 1
• Clogs or rigid stability shoes: These increase knee adduction moment by 15% and worsen joint loading 2
• Elevated heel shoes: Dress shoes with heels are the most unfavorable footwear type for knee loading 4, 2

Comprehensive Pain Evaluation Beyond Footwear

Immediate Assessment Points

• Quantify occupational demands: Determine exact hours spent standing/walking daily, as prolonged weight-bearing with inappropriate footwear compounds mechanical stress 1
• Assess pain pattern: Differentiate early stance phase pain (increased by all shoe types) from late stance pain (potentially reduced by appropriate footwear) 4
• Evaluate functional limitations: Assess impact on work activities, daily living tasks, and participation—not just pain intensity 1
• Screen for biomechanical instability: Look for evidence of excessive foot pronation or malalignment that may benefit from assistive devices 1, 5

Core Treatment Algorithm (Priority Order)

1. Weight Loss (Highest Priority for Overweight Patients) 6

• Target ≥5% body weight loss for measurable clinical improvement, with 10-20% producing progressive symptom improvement 6
• Implement structured programs with explicit weight-loss goals achieving mean loss of 6.1 kg (95% CI 4.7-7.6) 6
• Provide weekly supervised sessions for 8 weeks to 2 years, producing small but significant effects on pain (ES 0.20) and function (ES 0.23) 1, 6
• Combine with exercise: Concomitant exercise programs enhance weight loss efficacy 6

2. Exercise Therapy (Equal Priority with Weight Loss) 1, 7

• Prescribe ≥12 directly supervised sessions for superior outcomes: pain ES 0.46 vs 0.28 for fewer sessions (p=0.03) 1
• Include quadriceps strengthening: Reduces pain (ES 0.29) and improves function (ES 0.24) 1
• Add general aerobic fitness: Land-based and aquatic exercises both effective 7
• Integrate into daily life after initial supervised instruction 1

3. Workplace Modifications 1

• Consider assistive devices systematically: Walking aids, height-adjustable chairs, handrails to reduce pain and improve participation 1
• Implement activity pacing: Avoid "peaks and troughs" of activity that exacerbate symptoms 1
• Evaluate need for walking aids: Though evidence is contradictory, clinical experience supports their use for reducing joint load 1

4. Pharmacological Adjuncts 1, 7

• Start with paracetamol: Regular dosing up to 4,000 mg/day as first-line 7
• Add topical NSAIDs: Particularly for knee OA, fewer systemic side effects than oral NSAIDs 1, 7
• Reserve oral NSAIDs/COX-2 inhibitors: Only after paracetamol and topical NSAIDs insufficient, with careful cardiovascular/GI risk assessment 1, 7

Critical Pitfalls to Avoid

• Do not recommend glucosamine/chondroitin: Not supported by evidence 1, 7
• Avoid prescribing lateral wedge insoles routinely: Most evidence shows no benefit 1
• Do not overlook weight loss: This has the strongest dose-response relationship with symptom improvement in overweight patients 6
• Do not provide exercise advice without supervised sessions: Fewer than 12 supervised sessions produces significantly inferior outcomes 1
• Do not ignore occupational factors: Prolonged standing/walking requires workplace adaptations, not just footwear changes 1

Implementation Strategy

Immediate actions (Week 1):

• Replace current footwear with flat, flexible, supportive shoes with shock-absorbing properties 1, 2
• Initiate structured weight loss program with explicit goals 6
• Schedule ≥12 supervised exercise sessions 1

Short-term (Months 1-3):

• Ensure shoes worn ≥6 hours daily for pain benefit 1
• Monitor weight loss progress toward 5-10% reduction 6
• Assess workplace for needed assistive devices 1

Long-term (Months 3-6+):

• Transition exercise to daily life integration 1
• Continue weight management with weekly sessions 6
• Periodic review of footwear adequacy and workplace modifications 1