What are the management options for a patient with knee arthritis, considering their medical history and potential comorbidities such as gastrointestinal bleeding or impaired renal function?

Management of Knee Arthritis

Begin with acetaminophen (up to 4,000 mg/day) as first-line pharmacologic therapy for knee osteoarthritis, combined with sustained weight loss (if overweight/obese) and quadriceps strengthening exercises, reserving NSAIDs for patients unresponsive to acetaminophen or those with clinical effusion. 1

Initial Non-Pharmacologic Management

Weight Loss (if overweight/obese):

• Sustained weight loss reduces pain and improves function in overweight/obese patients with knee OA 1
• Combine diet and exercise for optimal results, though exercise may be superior to diet alone 1
• This intervention has no downside and provides additional health benefits beyond knee symptoms 1

Exercise Therapy:

• Quadriceps strengthening exercises and range of motion exercises are strongly recommended and reduce pain with effect sizes of 1.05 1
• Aerobic fitness training is equally efficacious to strengthening exercises over 18 months 1
• Exercise improves both pain and function with long-term benefits (6-18 months) 1

Patient Education:

• Education programs reduce pain and increase coping skills, though they have minimal impact on function 1
• Explain the nature of OA, prognosis, and individualized management plan 1

Pharmacologic Management Algorithm

First-Line: Acetaminophen

• Acetaminophen (up to 4,000 mg/day) is effective and comparable to ibuprofen in many patients short-term 1
• Safe for long-term use (up to 2 years studied) with no common contraindications, including in elderly patients 1
• Critical caveat: Both acetaminophen and NSAIDs carry FDA black box warnings—prescribe appropriately 1

Second-Line: NSAIDs (if acetaminophen fails)

• Oral NSAIDs (nonselective or COX-2 selective) are more efficacious than acetaminophen but with increased gastrointestinal side effects 1
• For patients with GI bleeding history or impaired renal function: Consider topical NSAIDs as a safer alternative 1
• Topical NSAIDs are particularly useful in patients ≥75 years old due to better safety profile 2
• No notable difference in GI adverse events between nonselective and COX-2 selective NSAIDs despite COX-2 agents being developed for this purpose 1

NSAID Safety Considerations:

• Monitor blood pressure, renal function, and liver function if prolonged use anticipated 3
• NSAIDs can cause serious cardiovascular events (MI, stroke), with risk increasing with longer use and higher doses 3
• Never use NSAIDs right before or after coronary artery bypass graft surgery 3
• NSAIDs can cause ulcers and bleeding without warning symptoms at any time during treatment 3
• Risk of ulceration/bleeding increases with: corticosteroids, anticoagulants, longer use, smoking, alcohol, older age, poor health 3
• NSAIDs diminish antihypertensive effects of ACE inhibitors, ARBs, and beta-blockers—monitor blood pressure 3
• In elderly, volume-depleted, or renally compromised patients, NSAIDs with ACE inhibitors/ARBs may cause acute renal failure 3
• Avoid combining NSAIDs with aspirin due to potential increased adverse effects 3
• Gastroprotection: Add proton pump inhibitor if GI bleeding risk factors present 4

Avoid: Opioids and Tramadol

• Oral narcotics (including tramadol) should NOT be used due to notable increase in adverse effects without consistent improvement in pain/function 1

Avoid: Dietary Supplements

• Glucosamine, chondroitin, turmeric, ginger extract, and vitamin D are not consistently effective 1
• Evidence is mixed with limited FDA oversight of supplement manufacturers 1

Intra-Articular Injection Therapy

Corticosteroid Injections (Preferred Injectable):

• Indicated for acute exacerbations, especially with effusion 1
• Supported by 19 high-quality and 6 moderate-quality studies 1
• Significant pain relief with effect size of 1.27 over 7 days 1
• Limitation: Duration of benefit typically only 3 months 1

Platelet-Rich Plasma (Alternative):

• Supported by 2 high-quality and 1 moderate-quality study showing reduced pain and improved function 1
• Critical limitation: Worse treatment response in patients with severe knee OA 1
• Concerns regarding cost and safety profile 1

Hyaluronic Acid (NOT Routinely Recommended):

• Not consistently supported by 17 high-quality and 11 moderate-quality studies 1
• Number needed to treat is 17 patients 1
• Current evidence does not identify which subset of patients benefit 1

Surgical Considerations

Arthroscopic Surgery:

• No benefit demonstrated for knee OA—do not routinely recommend 1

Meniscus Tears in OA Patients:

• Most meniscal tears in OA patients are degenerative and unlikely to improve with surgery 1
• Conservative management (exercise therapy for 4-6 weeks) is first-line treatment 5
• Surgery only indicated for truly obstructing displaced meniscus tears (e.g., bucket-handle tears) 1, 5

Total Knee Arthroplasty:

• Consider for end-stage OA (minimal/no joint space) with refractory pain and disability after exhausting conservative options 1, 5
• All studies show improvements in pain and function compared to baseline 1

Adjunctive Therapies

Physical Therapy Referral:

• Formal physiotherapy for supervised quadriceps strengthening is beneficial, though home exercises are also effective 1

Assistive Devices:

• Walking sticks and insoles may reduce pressure on affected joints, though evidence is limited 1, 2
• Bracing demonstrates significant pain and functional improvements 6

Common Pitfalls to Avoid

• Do not combine multiple NSAIDs—patients often fail to disclose over-the-counter NSAID use 4
• Do not ignore cardiovascular risk with NSAIDs—even short-term use carries CV risk at higher doses 4
• Do not use NSAIDs for more than 10 days without physician consultation if using OTC formulations 4
• Do not perform arthroscopic debridement for degenerative knee OA—no evidence of benefit 1
• Do not operate on degenerative meniscal tears—exercise therapy is first-line even with mechanical symptoms 5