What are the appropriate management and treatment options for a patient with left knee pain and swelling, potentially with a history of osteoarthritis (OA) or other chronic conditions?

Management of Left Knee Pain with Swelling

For a patient presenting with left knee pain and swelling, immediately administer an intra-articular corticosteroid injection if inflammatory signs or effusion are present, as this provides the most rapid and effective relief within 1-2 weeks and is specifically indicated for acute knee effusion. 1

Initial Diagnostic Approach

Look for these specific clinical features:

• Effusion presence (visible swelling, ballottement test positive) - predicts better response to corticosteroid injection 1
• Joint line tenderness - suggests meniscal pathology (83% sensitivity, 83% specificity) 2
• Age and onset pattern - gradual onset in patients ≥45 years with activity-related pain and <30 minutes morning stiffness indicates OA (95% sensitivity, 69% specificity) 2
• Range of motion limitation - compare to contralateral knee 3
• Antalgic gait - indicates significant functional impairment 3

Obtain standing AP, lateral, and Merchant view radiographs to assess for joint space narrowing, osteophytes, and compartmental involvement, which guide treatment decisions. 3

Immediate First-Line Treatment

Inject long-acting intra-articular corticosteroid (e.g., triamcinolone hexacetonide) directly into the affected knee joint for patients with visible effusion and acute pain. 3, 1 This provides:

• Pain relief beginning within 1-2 weeks 1
• Significant benefit lasting 1-12 weeks 1
• Superior response in patients with baseline effusion compared to those without 1

Critical caveat for diabetic patients: Monitor blood glucose for 1-3 days post-injection due to transient hyperglycemia risk. 1

Concurrent Pharmacological Management

Start acetaminophen (paracetamol) 4,000 mg/day maximum as the initial oral analgesic for all patients unless contraindicated. 3, 1 This is the preferred long-term oral analgesic due to excellent safety profile (1.5% adverse events). 3

If acetaminophen provides insufficient relief after 1-2 weeks, add NSAIDs:

• For patients <75 years: Oral ibuprofen 1,200-3,200 mg/day divided tid or qid with meals 3, 4
• For patients ≥75 years: Topical NSAIDs preferred due to superior safety profile 1, 5
• For patients with GI risk factors (age ≥60, history of peptic ulcer disease, GI bleeding, concurrent corticosteroids/anticoagulants): Use COX-2 selective inhibitors OR nonselective NSAIDs plus gastroprotective agent 3

Do not exceed ibuprofen 3,200 mg/day, and use the lowest effective dose for the shortest duration. 4

Essential Non-Pharmacological Interventions (Start Immediately)

Prescribe quadriceps strengthening exercises to preserve knee mobility and reduce pain - this has strong evidence for reducing morbidity. 3, 1, 5

Mandate weight reduction for overweight patients (BMI >25) - weight loss directly reduces knee OA risk and pain severity. 3, 1, 5 The case example demonstrates successful BMI reduction from 33 to 28 prior to surgery. 3

Provide structured patient education about the condition, self-management strategies, and realistic expectations. 3, 1

Consider assistive devices (cane in contralateral hand, knee bracing, insoles) for patients with antalgic gait. 3

Management of Persistent or Recurrent Effusion

Repeat intra-articular corticosteroid injection if the previous injection provided relief but symptoms recurred. 1 The case example shows 2 months of relief before symptom recurrence. 3

Consider hyaluronic acid injections as second-line option if corticosteroids fail or provide inadequate duration of relief, though effect sizes are modest (0.04-0.9) and require 3-5 weekly injections. 1

Important limitation: Patients with more severe structural disease and baseline effusion respond worse to hyaluronic acid. 1

Critical Pitfalls to Avoid

Do not withhold corticosteroid injection in patients without visible effusion - while effusion predicts better response, patients without visible effusion may still benefit significantly. 1

Do not use continuous passive motion machines postoperatively - these are not supported by evidence. 3

Avoid both corticosteroid and hyaluronic acid injections within 3 months prior to planned knee replacement surgery due to increased infection risk. 1

Do not prescribe opioid analgesics as first-line therapy - reserve for severe refractory pain when NSAIDs are contraindicated or ineffective. 3

Surgical Referral Criteria

Refer for total knee arthroplasty consideration when:

• Radiographic evidence shows moderate-to-severe tricompartmental degenerative changes 3
• Patient has refractory pain and disability despite optimal conservative management (weight loss, physical therapy, pharmacological treatment, intra-articular injections) 3, 1
• Pain significantly limits activities of daily living and quality of life 3

Preoperative optimization is essential: Achieve BMI <30, optimize diabetes control, strengthen quadriceps through structured physical therapy, and avoid narcotic medications. 3