From the Guidelines
Management of knee effusion involves a stepwise approach, with the most recent and highest quality study recommending aspiration and intra-articular corticosteroid injections as effective treatments. According to the study published in 2023 1, knee joint aspiration, often with fluoroscopy or ultrasound guidance, has been found to be extremely useful in diagnosing joint infection after total knee arthroplasty. The synovial fluid is usually evaluated with Gram stain, total and differential cell counts, and aerobic and anaerobic cultures.
The following steps are recommended for managing knee effusion:
- Rest, ice, compression, and elevation (RICE protocol) for mild to moderate effusions
- Over-the-counter NSAIDs like ibuprofen (400-800mg three times daily) or naproxen (500mg twice daily) to reduce inflammation and pain
- Acetaminophen (1000mg every 6 hours, maximum 4000mg daily) as an alternative for those who cannot take NSAIDs
- Aspiration to relieve pressure and obtain fluid for analysis, using aseptic technique and a lateral approach
- Intra-articular corticosteroid injections, such as methylprednisolone (40-80mg) or triamcinolone (20-40mg), for longer-term relief
- Physical therapy focusing on quadriceps strengthening and range of motion exercises to maintain joint function and prevent muscle atrophy
It is essential to address the underlying cause of recurrent or chronic effusions, which may include treatment for osteoarthritis, rheumatoid arthritis, or repair of structural issues like meniscal tears. Effusions caused by infection require prompt antibiotic therapy based on culture results, as recommended by the study published in 2017 1. The management approach should be tailored to the severity of symptoms and the underlying etiology of the effusion.
From the Research
Management of Knee Effusion
The management of knee effusion, which is the accumulation of excess fluid in the knee joint, can be approached through various methods.
- Aspiration of the knee joint is a common procedure used to relieve pain and aid in diagnosis, especially in cases of unknown origin or when there is a need for immediate clinical relief 2.
- The use of nonsteroidal anti-inflammatory drugs (NSAIDs) has been shown to improve disease-specific quality of life and decrease pro-inflammatory cytokine levels in the synovial fluid of patients with knee osteoarthritis 3.
- Intra-articular injections of corticosteroids or hyaluronic acid can provide temporary relief, while nerve ablation treatments using radiofrequency or cryotherapy may offer longer-lasting analgesic effects 4.
- Regenerative medicine, including platelet-rich plasma or mesenchymal stem cells, is a promising treatment that can improve pain and mobility for a longer period 4.
Considerations for Management
When managing knee effusion, it is essential to consider the underlying pathology, as the approach can range from anti-inflammatory medication for inflammation to operative intervention for structural abnormalities 5.
- A thorough history and examination are crucial in determining the primary pathology and informing the investigations that should be carried out 5.
- The location of pain and tenderness can aid in localizing structural pathology, even before radiological tests are requested 5.
Treatment Outcomes
The effectiveness of aspiration in knee joint effusion management has been evaluated, and while it exhibits temporary improvement in clinical parameters, this improvement is often short-lived due to the early re-accumulation of the effusion 2.
- The use of disease-modifying antirheumatic drugs, such as methotrexate, can be beneficial in minimizing long-term joint damage, especially when used in combination with other agents 6.