What is the treatment for knee effusion due to injury?

Treatment for Knee Effusion Due to Injury

Intra-articular corticosteroid injection is the first-line treatment for acute knee effusion following injury, particularly when accompanied by pain or inflammatory signs, providing significant relief within 1-2 weeks. 1, 2, 3

Immediate First-Line Treatment

Perform intra-articular corticosteroid injection for acute traumatic knee effusion with pain, especially when inflammatory signs are present. 1, 2, 3

• Inject long-acting corticosteroid (e.g., triamcinolone hexacetonide) directly into the affected joint. 4
• Expect pain relief within 1-2 weeks, with significant differences between steroid and placebo lasting through 4 weeks. 1
• Benefits typically persist for 1-12 weeks, though this is shorter-lived than some alternatives. 1, 2
• Patients with visible effusion respond better to intra-articular corticosteroids than those without effusion. 1
• In diabetic patients, monitor glucose levels for 1-3 days post-injection due to transient hyperglycemia risk. 1, 2
• Advise patients to avoid overuse of the injected joint for 24 hours following injection. 2

Concurrent Oral Analgesic Therapy

Start oral acetaminophen (paracetamol) simultaneously with or without corticosteroid injection for pain control. 1, 2, 3

• Dose up to 4,000 mg/day as initial analgesic for mild to moderate pain. 1, 2, 3
• Acetaminophen is safe for long-term use with minimal side effects and may reduce synovial inflammation comparably to NSAIDs. 5
• If acetaminophen is insufficient, add NSAIDs (oral or topical) for patients with persistent effusion. 1, 2
• NSAIDs have demonstrated efficacy with effect size median of 0.49 in patients with effusion. 2
• Topical NSAIDs offer clinical efficacy with better safety profile, particularly in elderly patients. 4
• Remember that elderly persons are at high risk for NSAID side effects, including gastrointestinal, platelet, and nephrotoxic effects, so avoid high doses for prolonged periods. 4

Essential Non-Pharmacological Interventions

Implement these measures concurrently with pharmacological treatment from the outset. 4, 2

• Prescribe quadriceps strengthening exercises to preserve normal knee mobility and prevent functional decline. 1, 3
• Recommend weight reduction for overweight patients to reduce joint pressure and mechanical stress. 1, 3
• Provide regular patient education about the injury, expected recovery timeline, and self-management strategies. 1, 2, 3
• Consider physical supports such as walking sticks, insoles, or knee bracing to offload the injured joint. 2, 3

Management of Persistent or Recurrent Effusion

If effusion persists beyond 1-2 weeks despite initial treatment, consider the following approach:

• Repeat intra-articular corticosteroid injection if the previous injection provided relief, as this indicates responsiveness to treatment. 1, 2
• Consider hyaluronic acid injections as a second-line option, though effect sizes are relatively small (0.04-0.9) and require 3-5 weekly injections. 1
• Joint lavage plus intra-articular steroid may be considered for additional benefit in refractory cases, though this requires further study and cannot be routinely recommended. 3, 6

Critical Pitfalls to Avoid

Do not perform aspiration routinely for traumatic knee effusion. While aspiration provides temporary improvement in pain and range of motion, this benefit lasts only for the first week due to early re-accumulation of effusion, with no difference in clinical outcome at follow-up. 7

• Aspiration should be reserved for effusions of unknown origin to establish diagnosis or for immediate clinical relief when necessary. 7
• Aspiration should be performed with consideration in the presence of trauma, as it does not improve long-term outcomes. 7
• Avoid both corticosteroid and hyaluronic acid injections within 3 months prior to knee replacement surgery due to increased infection risk. 1, 2
• Do not reserve corticosteroid injection only for patients with visible effusion—while effusion predicts better response, patients without visible effusion may still benefit. 1

Surgical Consideration for Refractory Cases

Joint replacement should be considered for patients with refractory pain, disability, and radiographic evidence of structural deterioration despite conservative measures. 1, 2, 3

• Total knee replacement demonstrates effectiveness in improving quality of life, reducing pain, and improving function in severely incapacitated patients. 1
• Orthopedic consultation and evaluation for osteotomy or total joint arthroplasty is appropriate for severe symptomatic cases unresponsive to aggressive conservative management. 6