Knee osteoarthritis: from the first ache to the right treatment

What knee osteoarthritis is

The cartilage that covers the thigh bone, the shin bone and the kneecap thins over time. The joint reacts with inflammation, fluid and bony spurs. It is not simply wear from age. It is a condition of the whole joint, which affects the menisci, the ligaments and the bone too.

The knee has three compartments: inner, outer and the one behind the kneecap. The inner one wears most often, and the leg starts to bow.

The symptoms

• Pain on stairs, when getting up from a chair and after a long walk.
• Stiffness in the morning or after rest, lasting a few minutes.
• Swelling that comes and goes.
• Creaking on movement. Without pain, it does not matter.
• In later stages, pain at night and a knee that will not straighten fully.

Why it happens

• Age and family history.
• Extra body weight. Every kilo is multiplied with each step.
• Old injuries, such as a meniscus tear or an ACL tear.
• Leg alignment: bow legs or knock knees load the joint unevenly.
• Heavy manual work with a lot of kneeling and lifting.

How it is diagnosed

The key test is an X-ray taken standing, with body weight on the knee. Only then does it show how far the joint space has narrowed. An X-ray taken lying down can make a knee look better than it is.

An MRI scan rarely adds anything when the wear already shows on the X-ray. It will almost always show a degenerative meniscus tear too, which is usually not the cause of the pain.

Treatment without surgery

• Strengthening. A strong quadriceps is the best medicine for the knee.
• Low-impact exercise. Cycling, swimming, walking on level ground.
• Weight loss. Even 5 kilos make a difference to the pain.
• Medication. Anti-inflammatory gel or tablets for flare-ups, under medical guidance.
• Aids. An unloading brace or insoles, when leg alignment justifies them.

Injections into the knee

When the above are not enough, injections into the joint can give a period with less pain.

• Cortisone. Quick relief in a sharp flare, with a short effect.
• Hyaluronic acid. Improves joint lubrication in early and moderate wear.
• PRP. Growth factors from your own blood. See when PRP helps.

No injection rebuilds cartilage. All of them work better together with exercise.

The surgical options

• Osteotomy. In younger patients with wear in one compartment and a leg out of line, correcting the alignment shifts the load to the healthy side.
• Partial knee replacement. Only the worn compartment is replaced.
• Total knee replacement. When the wear affects the whole knee. See the pages on total knee replacement and on CORI® robotic assistance.

A keyhole “clean-out” does not help osteoarthritis and is not offered for that purpose.

What you can do every day

• Move every day, even a little. Staying still makes stiffness worse.
• Avoid deep squats and a lot of kneeling.
• On stairs, go up with the good leg and down with the sore one.
• Ice after a tiring day, warmth in the morning for stiffness.
• Shoes with good cushioning.

Common questions