European Experts Define Role of Hyaluronic Acid in Knee OA

Intra-articular injection of hyaluronic acid (IAAH) in knee osteoarthritis (OA) is growing, with literature suggesting a favourable benefit/risk ratio and efficacy that may surpass that of nonsteroidal anti-inflammatory drugs (NSAIDs). However, the level of evidence varies. Knee OA is a complex disease, and hyaluronic acid is effective in certain pathophysiological aspects.

The EUROVISCO group, which includes 12 experts on OA from eight European countries, reached a consensus on viscosupplementation with IAAH for knee OA. This treatment is suitable for symptomatic knee OA, regardless of age or comorbidities, but is not recommended during flare-ups or in the presence of significant synovial effusion. Caution is recommended for pregnant and breastfeeding women.

The experts of the EUROVISCO group emphasised in the consensus, which was published in the journal Cartilage, that “Rather than challenging the effectiveness of IAHA in the general population, we must distinguish the good, bad, and poor indications and identify the characteristics of patients which can influence the response to this treatment.” The group used the Delphi method to develop 40 evidence-based recommendations for knee OA and IAAH injections.

Age and Comorbidities

IAAH injections are well tolerated with no drug interactions, making them suitable for most patients with symptomatic knee OA, regardless of age (level 1A evidence). IAAH injections are a choice for frail populations (level 2B evidence).

Experts agree that viscosupplementation is a viable option for patients with type 1 or type 2 diabetes, gout, metabolic syndrome, and cardiovascular or renal disease, although the evidence is limited. The treatment is recommended for patients with moderate to severe obesity (body mass index [BMI], 30-40, level 1B evidence) and, with less evidence, for those with morbid obesity (BMI > 40).

A cautious approach is advised during pregnancy, prioritising intra-articular injections of anti-inflammatories and delaying viscosupplementation until after childbirth unless severe pain necessitates earlier intervention with obstetric approval. Similar caution applies to breastfeeding, as viscosupplementation may reduce the need for other treatment options for knee OA.

Flare-Ups and Inflammation

IAAH injections may be beneficial in early symptomatic knee OA, even when x-rays appear normal, offering a “window of opportunity” for early treatment.

IAAH injections can be considered for patients with mild to moderate femorotibial or patellofemoral OA, including advanced radiographic cases. If no alternative treatment is available, viscosupplementation remains an option for those with moderate pain or those who prefer to avoid surgery.

The treatment is also suitable for painful knees (depending on the intensity of the pain), meniscal calcinosis, mild to moderate deformities (varus or valgus), limited synovial effusion (less than 10 ml), and post-traumatic knee OA (for symptomatic relief or secondary prevention).

However, it is not recommended for large synovial effusions (> 20 mL), acute knee OA flare-ups, and inflammatory knee pain, where NSAIDs, ice, or intra-articular steroids may be more appropriate.

This story was translated from Univadis France using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.