Knee Surgery

The knee is a hinge doing a much more complicated job than a hinge. It bends, rotates slightly, absorbs load, and stays stable through all of it, held by ligaments and cushioned by two menisci. Injuries usually involve one of those structures, and the assessment is about establishing which.

Meniscus tears

The menisci are two wedges of cartilage that spread load across the knee. They tear in two quite different ways, and confusing the two leads to unnecessary surgery.

Acute tears happen with a twist, often in sport, usually in a younger person with an otherwise healthy knee. Where the tear is in the outer part with a blood supply, it can often be repaired rather than trimmed, which preserves the meniscus and protects the knee long term.

Degenerative tears develop gradually in knees that are already showing wear. These frequently show up on scans in people whose pain is actually coming from the arthritis, not the tear. The evidence here is clear enough to be worth stating plainly: for degenerative tears in arthritic knees, arthroscopy generally does not outperform a properly structured rehabilitation programme.

The exception is genuine mechanical symptoms. A knee that physically locks, catches, or gives way because something is trapped in the joint is a different situation, and that is when arthroscopy earns its place.

Our guide to knee arthroscopy and meniscus surgery covers this in more detail.

ACL and ligament injuries

The anterior cruciate ligament is usually injured by a twisting movement rather than a collision, often with a pop, immediate swelling, and a knee that feels unstable afterwards.

Not everyone needs a reconstruction. Someone whose work and activity do not involve pivoting may do well with rehabilitation alone. Someone returning to a cutting or pivoting sport, or whose knee gives way in daily life, usually does better reconstructed.

Reconstruction replaces the torn ligament with a graft. The operation is the shorter part of the process. Recovery takes nine to twelve months and is governed by measured strength and control, not by dates. Returning before those measures are met is the main reason grafts fail.

There is a fuller account in our article on ACL reconstruction recovery.

Cartilage injuries

Damage to the joint surface itself is different from a meniscus tear, and harder to treat. Options depend on the size and location of the defect and on the age and demands of the patient, and range from simply managing symptoms to procedures that stimulate or replace the surface.

Honest expectation setting matters here more than anywhere else in the knee. Cartilage does not heal back to normal.

Knee arthritis and replacement

Where the joint surface has worn out broadly, the conversation moves from repair to replacement. That is a substantial operation with a substantial recovery, and it is worth doing when the knee is genuinely limiting life rather than at the first sign of wear.

Non-surgical management, including weight management, targeted strengthening, activity modification, and injection, does real work in the meantime and should be exhausted first. Our introduction to total knee replacement covers what the operation involves.

Work-related knee injuries

Knee injuries are common in work involving kneeling, climbing, twisting under load, or falls. If yours happened at work, say so when you call: it changes what documentation we collect from the first visit. See workers’ compensation.

What to expect

Examination, review of any imaging you already have, and a plain-language explanation of what is wrong. Where an operation is indicated we will say so and explain what it would and would not achieve. Where it is not, we will say that as well.