What is the treatment for pain associated with knee effusion or hematoma?

Treatment for Pain Associated with Knee Effusion or Hematoma

For acute knee effusion with pain, intra-articular injection of long-acting corticosteroid is the first-line treatment, providing significant pain relief within 1-2 weeks, especially when effusion is present. 1

Initial Pharmacological Management

First-Line Treatment for Effusion with Pain

• Intra-articular corticosteroid injection is indicated for acute exacerbation of knee pain with effusion, demonstrating superior efficacy (effect size 1.27) compared to placebo, with benefits lasting 1-24 weeks 2, 1
• The presence of effusion predicts better response to corticosteroid injection, though benefits are relatively short-lived 2, 1
• Pain relief typically occurs within 7 days, with functional improvements noted within 1-4 weeks 2

Oral Analgesics

• Start with oral paracetamol (acetaminophen) up to 4g/day for mild to moderate pain, which is safe for long-term use and should be the preferred oral analgesic if effective 2, 1
• NSAIDs (oral or topical) should be used in patients unresponsive to paracetamol, particularly when effusion is present, with demonstrated efficacy (effect size median 0.49) 2, 1
• Naproxen 375-750 mg twice daily has been shown effective for pain relief, though higher doses (1500 mg/day) are associated with increased gastrointestinal adverse events 3

Management of Hematoma

Cold Therapy Application

• Apply localized cold therapy with or without pressure for closed bleeding and hematoma, which reduces hematoma formation and blood loss 2
• Cold compression demonstrated reduction in hematoma size by approximately 20 cm² over 180 minutes in post-procedural patients 2
• In total knee arthroplasty patients, cold compression reduced calculated total body blood loss by 610 mL (95% CI, 415.6–804.4) 2
• Cold therapy should be applied to limited-size injuries to avoid hypothermia risk, particularly in pediatric patients 2

Aspiration Considerations

• Aspiration provides only temporary improvement (first week only) due to early re-accumulation, and should be reserved primarily for diagnostic purposes in effusions of unknown origin or for immediate clinical relief 4
• For traumatic hemarthrosis, aspiration may be considered to minimize harmful effects of blood breakdown products on cartilage, though no consensus exists on routine drainage 5

Non-Pharmacological Interventions

Concurrent non-pharmacological treatment should include:

• Regular patient education about the condition 2, 1
• Exercise programs, especially quadriceps strengthening exercises 2, 1
• Weight reduction if overweight 2, 1
• Physical supports such as walking sticks, insoles, or knee bracing 1

Refractory Cases

Second-Line Options

• For persistent effusion despite initial treatment, consider hyaluronic acid injections (3-5 weekly injections), which provide pain relief for several months but with slower onset than corticosteroids 2, 1
• Joint lavage plus intra-articular steroid may provide additional benefit, particularly in the first month 2, 1

Surgical Consideration

• Joint replacement should be considered for refractory pain with disability and radiographic evidence of deterioration 2, 1

Important Caveats

• Avoid combining NSAIDs with aspirin, as aspirin increases naproxen excretion rates and the combination increases adverse event frequency without demonstrated additional benefit 3
• Corticosteroid benefits are relatively short-lived (1-24 weeks), so plan for additional interventions if symptoms recur 2, 1
• In traumatic hemarthrosis, early arthroscopic evaluation may be warranted if ACL injury, meniscal tears, or chondral damage is suspected based on mechanism and physical examination 6