A hyaluronic knee injection places a gel made of hyaluronic acid into the knee joint, usually to ease pain from osteoarthritis. Doctors call it an intra-articular injection. This page explains what the gel is, what the research shows and what an OPD visit involves, and covers the knee only, not cosmetic fillers.
What is hyaluronic acid for joints?
Hyaluronic acid is a natural part of the fluid that lubricates a joint and gives it its thick, slippery quality. In osteoarthritis, the cartilage surface wears and the fluid changes. The injected product is a purified form of hyaluronic acid supplied as a gel. The idea is to improve lubrication in the knee. Whether it does so reliably in people is still debated.
Products differ in how many injections make up a course, from a single injection to several given a week apart. Your doctor explains the schedule for the one proposed.
How a hyaluronic acid intra-articular injection is given
- History and examination of the knee, with a review of your X-ray.
- A discussion of what to expect, the uncertainty in the evidence and the risks, then your consent.
- The skin is cleaned and the needle is placed into the joint, with ultrasound guidance if the doctor feels it is needed.
- The gel is injected, a small dressing is applied and you rest briefly before leaving.
The injection itself takes a few minutes. Most people walk out the same day.
Hyaluronic acid for joints: what the evidence says
Trials and reviews of hyaluronic acid in knee osteoarthritis do not agree. Some report modest pain relief lasting a few months compared with saline injection, mostly in mild to moderate arthritis. Others find the difference small, or no greater than a placebo effect. In practice, some patients feel better and others notice nothing.
The evidence is mixed and guidelines differ. Some advise against hyaluronic acid injections for knee osteoarthritis, while others accept them for selected patients who cannot take, or have not benefited from, other treatments.
It has not been shown to rebuild cartilage or reverse arthritis, and it does not correct the alignment of the knee. If it helps, the effect is temporary. It may buy time, but it is not a substitute for surgery when the joint is badly worn.
Who may be considered
- Adults with mild to moderate knee arthritis whose pain is not controlled well enough by exercise, weight management and pain medicines.
- People who cannot take anti-inflammatory tablets because of stomach, kidney or heart concerns, once exercise, weight management and topical pain relief have been tried.
- People who want a non-surgical step before discussing knee replacement.
Caution is needed with a skin infection near the knee, a hot and swollen knee, allergy to a component of the product (including bird-derived products, if the gel is made from them), and blood-thinning medicines. Arthritis that is bone on bone is less likely to respond. Knee pain from a meniscus tear with locking, or from a ligament injury, needs its own assessment; see meniscus tears.
Another injection sometimes discussed for knee arthritis is PRP, described on the PRP injection page. The choice between them is made after examination.
After the injection and what can go wrong
Soreness or swelling in the knee for a day or two is common, and a few people have a temporary flare of pain, and a sudden severe flare should be reviewed promptly. Infection and bleeding are uncommon but possible with any joint injection. You will be advised to avoid strenuous activity for a short period and about which pain medicines to use.
When to see a doctor
See a doctor for knee pain that has lasted more than a few weeks, or that comes with swelling, giving way or locking. After an injection, seek medical care the same day for fever, a hot, red or swollen knee, or pain that is getting worse.
How to book
Dr. Aman Khanna sees knee patients at Mahavir Health Campus, Ring Road, Athwa Gate, Surat, Monday to Saturday, 4 to 6 PM. To book, use WhatsApp at +91 89808 22922 or the clinic and hours page. WhatsApp is for booking only; the knee is examined at the visit.