Hyaluronic acid is a natural component of synovial fluid. It contributes to lubrication within the joint and supports the shock-absorbing properties of the synovial fluid.

In the treatment, a hyaluronic acid preparation is introduced directly into the knee joint with a fine needle. The therapy is among the various forms of hyaluronic acid therapy and is planned individually only after an orthopedic examination.

A hyaluronic acid injection can be discussed for selected patients with degenerative conditions of the knee joint, particularly for:

• Knee osteoarthritis or gonarthrosis;
• activity-related joint pain;
• limited mobility;
• recurrent symptoms despite conservative treatment;
• intolerance of or insufficient effect of other measures.

Not all knee pain is caused by osteoarthritis. The menisci, ligaments, tendons, bursae, or the kneecap can also cause symptoms. Therefore, before treatment it must first be determined whether the knee joint itself is the likely source of pain.

Further information on the condition can be found on our page on knee osteoarthritis. The existing knee osteoarthritis page describes pain, movement limitations, and various conservative as well as surgical treatment options.

The goal of treatment is possible relief of symptoms and an improvement in joint function. The hyaluronic acid injection, however, can neither fully restore damaged joint cartilage nor cure knee osteoarthritis.

The potential effect and its duration differ from person to person. Scientific evaluation is also not uniform. The AAOS guideline does not recommend intra-articular hyaluronic acid injections for symptomatic knee osteoarthritis for routine use. Therefore, the decision should be made after an individual examination, informed discussion, and consideration of treatment alternatives.

Medical examination

First, the symptoms, their duration, and previous treatments are discussed. The doctor examines the knee and evaluates any existing X-ray, ultrasound, or MRI findings.

Preparation

The area around the injection site is carefully disinfected. If there is a significant joint effusion, it may first be assessed whether additional diagnostic or therapeutic measures are required.

Injection into the knee joint

The hyaluronic acid preparation is injected directly into the knee joint with a fine needle. Depending on the anatomical conditions and the individual findings, the position of the needle can be monitored using ultrasound.

Follow-up

After the injection, the immediate reaction is assessed. You will then receive recommendations on weight-bearing of the knee joint and on the further treatment plan.

The number and intervals of injections depend on the preparation used. Depending on the product, a single application may be planned or a treatment series with multiple appointments may be carried out.

Whether another injection is advisable is determined based on the effect to date, tolerability, and the individual findings. 

Inform the treating physician in particular about:

• acute infections or fever;
• skin inflammations or injuries to the knee;
• allergies to medications or components of the preparation;
• blood clotting disorders;
• blood-thinning medications;
• pregnancy;
• medications taken regularly.

Medications must not be discontinued or altered before the treatment without consulting a doctor.

After the treatment, it may be advisable to temporarily rest the knee. Intensive sporting activities, prolonged running, and heavy strength training should initially be avoided in accordance with medical advice.

Temporary pain or a feeling of pressure at the injection site may occur. In the event of increasing pain, pronounced swelling, marked redness, increased warmth, or fever, the practice should be contacted promptly.

A hyaluronic acid injection is only one possible measure within a more comprehensive treatment plan. Depending on the findings, it can be combined with the following therapies:

• Physiotherapy and targeted muscle training;
• Adjustment of physical load;
• Weight reduction if appropriately indicated;
• Pain medication;
• Bandages or orthoses;
• additional injection therapies;
• surgical evaluation in advanced osteoarthritis.

You can find an overview of the different conservative, interventional, and surgical options on our page on osteoarthritis therapy.

General information on other medications and forms of knee injection can also be found on the page on infiltration at the knee. This page is already listed as its own treatment area in the therapy offerings of the Orthopedic Center.