What are the management options for knee pain?

Management of Knee Pain

Start with acetaminophen (up to 4,000 mg/day) as first-line oral analgesic combined with exercise therapy focused on quadriceps strengthening, and add weight reduction if the patient is overweight. 1, 2, 3

Initial Assessment Priorities

Before initiating treatment, identify:

• Age and activity level: Patients <40 years with anterior knee pain during squatting (91% sensitive) likely have patellofemoral pain, while those ≥45 years with activity-related pain and <30 minutes morning stiffness (95% sensitive) likely have osteoarthritis 4
• Trauma history: Twisting injuries with joint line tenderness (83% sensitive/specific) and positive McMurray test (61% sensitive, 84% specific) suggest meniscal tears 4
• Red flags: Acute swelling with hemarthrosis suggests ligamentous rupture or fracture; fever/systemic symptoms warrant evaluation for septic arthritis 5

First-Line Treatment Algorithm

Pharmacological Management

Step 1: Acetaminophen

• Initiate acetaminophen up to 4,000 mg/day as the preferred first-line oral analgesic due to favorable safety profile 1, 2, 3
• This is the recommended long-term oral analgesic if successful 1

Step 2: Topical NSAIDs (if acetaminophen insufficient after 2-4 weeks)

• Topical NSAIDs are particularly preferred in patients ≥75 years old due to better safety profile compared to oral NSAIDs 2, 3
• Topical applications (NSAIDs, capsaicin) have clinical efficacy and are safe 1

Step 3: Oral NSAIDs (if topical NSAIDs insufficient)

• Consider oral NSAIDs in patients unresponsive to acetaminophen 1, 3
• Critical caveat: In patients with increased gastrointestinal risk, use non-selective NSAIDs with effective gastroprotective agents, or selective COX-2 inhibitors 1, 3
• Ibuprofen has been shown comparable to aspirin in controlling pain/inflammation with statistically significant reduction in milder GI side effects 6

Non-Pharmacological Management (Initiate Simultaneously with Pharmacological)

Exercise Therapy (Mandatory)

• Joint-specific exercises targeting quadriceps strengthening and range of motion reduce pain and improve function 1, 2, 3
• Large RCTs demonstrate that cumulative incidence of disability is lower in exercise groups (both aerobic and resistance) compared to no-exercise controls 1
• Home exercise programs, supervised land/water exercises, aerobic conditioning, and isokinetic regimens all show effectiveness 1

Weight Reduction (If Overweight)

• Weight loss reduces risk of knee OA and decreases pressure on knee joints 1, 2, 3
• This is particularly important as large cohort studies show weight loss reduces knee OA risk 1

Patient Education

• Regular education programs (individualized packages, phone calls, group education, patient coping skills) show effect sizes of 0.57-1.0 with long-term improvements lasting 6-18 months 1
• Education empowers patients to better manage their condition 4

Assistive Devices

• Walking sticks, insoles, or knee bracing reduce pressure on affected areas 1, 2, 3

Second-Line Interventions

For Acute Flares with Effusion

• Intra-articular corticosteroid injections are indicated for acute exacerbations, especially if accompanied by effusion 1, 2, 3
• These provide effective short-term pain relief 3, 7

For Refractory Cases

• Opioid analgesics (with or without acetaminophen) are useful alternatives when NSAIDs are contraindicated, ineffective, or poorly tolerated 1
• Important caveat: Tramadol has poor risk-benefit trade-off and is not routinely recommended 8
• Radiofrequency (conventional and cooled) of genicular nerves has been shown effective when conservative treatment fails 7

Surgical Considerations

Joint replacement must be considered in patients with:

• Radiographic evidence of knee OA 1
• Refractory pain and disability despite appropriate conservative measures 1, 4
• End-stage OA (minimal/no joint space with inability to cope with pain) after exhausting all conservative options 4

Avoid arthroscopic surgery: This has been shown to have no benefit in knee osteoarthritis 8

Treatment Tailoring

Treatment should be individualized based on: 1

• Knee risk factors (obesity, adverse mechanical factors, physical activity)
• General risk factors (age, comorbidity, polypharmacy)
• Level of pain intensity and disability
• Signs of inflammation (effusion)
• Location and degree of structural damage

Common Pitfalls

• Do not skip non-pharmacological interventions: Optimal management requires combination of pharmacological and non-pharmacological modalities 1
• Do not routinely image all patients: Radiographic imaging is not recommended for all patients with possible knee OA 4
• Do not rush to surgery for meniscal tears: Conservative management (exercise therapy for 4-6 weeks) is appropriate for most meniscal tears, including degenerative tears even with mechanical symptoms 4