Viscosupplementation consists of performing one or more injections of hyaluronic acid in an osteoarthritis of the knee or hip to improve mobility and relieve pain. In which case is it recommended? And how is this examination carried out?

In a healthy joint, the cartilage is covered by a viscous and elastic substance: the synovial fluid. Thanks to its elastic properties, the synovial fluid moistens, nourishes and protects the joint in order to protect it from shocks. Hyaluronic acid is one of the many elements that make up synovial fluid. 

With aging, the joints are affected by osteoarthritis and hyaluronic acid is depleted. The synovial fluid gradually loses its viscous and elastic properties with age, which makes the cartilage more vulnerable and leads to wear that causes pain and discomfort in the actions of daily life. 

The infiltration of hyaluronic acid, also called viscosupplémentation, consists of injecting a gel based on hyaluronic acid directly into the joint affected by osteoarthritis and aims to restore the properties of the synovial fluid and recreate its shock-absorbing function. 

Hyaluronic acid also has a very interesting anti-inflammatory and analgesic effect for reducing joint pain and improving the functional state of the osteoarthritis joint.

Compared to corticosteroid injections, hyaluronic acid injections work slowly but their effect lasts longer, ranging from 8 months to 1 year. This treatment can be repeated.

Gonarthrosis (osteoarthritis of the knee) is the pathology for which the effectiveness of hyaluronic acid has been tested the most. Hyaluronic acid injections can therefore be prescribed in the knee and hip in case of:

• Moderate but painful osteoarthritis to correct the loss of elasticity and the amount of hyaluronic acid naturally present in the synovial fluid;
• Resistant to other treatments, or when these are poorly tolerated or contraindicated;
• Severe osteoarthritis, especially after rapid destruction of cartilage;
• Complicated or impossible surgery.

Rehabilitation physician, rheumatologist and surgeon are the only practitioners who can prescribe viscosupplementation in a doctor’s office. 

Hip or knee viscosupplementation is not really painful, the pain is identical to a blood test. In general, avoid stressing the joint that has undergone viscosupplementation a few days after the operation.

The act lasts between 15 and 20 minutes.

Before the injection, report any discomfort or symptoms you may have. To start, a skin disinfection protocol will be systematically carried out. Then the doctor will insert a very fine needle into the painful area. After the needle is inserted, the doctor will try to remove fluid. We call this gesture “puncture”.

Secondly, the doctor will inject hyaluronic acid.

The needle will then be withdrawn.

Most often, three injections a week apart are recommended, but it can be done as a single injection. In all cases, it is recommended to renew the treatment every year.

Hyaluronic acid allows:

• To overcome pain in movement;
• Improve joint mobility;
• To reduce the intake of analgesics;
• To reduce the intake of anti-inflammatory drugs;
• To delay the fitting of a prosthesis by several years.

• Pain: a transient and generally moderate pain when the needle is introduced which may persist at the injection site;
• Infection: it is quite exceptional and can be avoided by a good injection technique and careful preparation of the skin;
• Moderate swelling: inflammatory reaction, it is advisable to combine icing and pain relief treatment such as paracetamol. If the swelling occurs within 24 to 48 hours, it is necessary to consult;
• In case of inflammation associated with fever or chills, call the office as soon as possible;
• Hematoma: rare and usually moderate, the hematoma generally disappears within a few days;
• Other complications: rare and not serious vagal discomfort may occur;
• Rare cases of knee swelling and local painful reactions which can be reduced by an ice pack.