What causes knee pain?
Knee pain most often comes from osteoarthritis, where the cartilage covering the joint surfaces wears down over time, but it can equally come from a specific mechanical problem such as a meniscal tear, a ligament injury, or a loose fragment of cartilage or bone catching inside the joint. Avascular necrosis (AVN), a poor blood supply to the cartilage and bone, is a less common cause and can affect younger patients. Working out which one you have matters, since a mechanical problem is treated very differently to widespread arthritis.
Common symptoms
- A dull ache that may come and go, or be constant
- Pain going up or down stairs, often one of the earliest signs
- Instability, catching, locking or a sense the knee may give way
- Swelling around the joint, particularly after activity
- Grinding or clicking felt when the joint moves
How it is diagnosed
A history of your symptoms and an examination that reproduces the problem usually point towards the likely cause. X-rays check the joint surfaces and confirm whether arthritis is present and how advanced it is. An MRI is used when a mechanical problem is suspected, since it shows the meniscus, cartilage and ligaments in detail that X-rays cannot.
Your treatment options
Lifestyle & physiotherapy
Targeted strengthening, activity modification and weight optimisation, always the starting point.
Joint injections
Image-guided steroid or lubricant injections can settle pain for months, and help confirm the diagnosis.
Knee arthroscopy
Keyhole surgery to treat meniscal tears, loose fragments and other mechanical problems, usually as a day case. See Knee Arthroscopy.
Knee replacement
Partial or total replacement when conservative care no longer holds the line. See Knee Replacement Surgery.
Revision knee replacement
Specialist care if a previous knee replacement has become painful, loose or worn. See Revision Knee Replacement.
When should I seek help?
If your knee locks, gives way, or keeps you from your usual activities, it is worth having it assessed. A clear diagnosis matters, keyhole surgery helps mechanical problems but rarely helps arthritis, and the right advice depends on knowing which you have.
Get your knee assessed
Treatment Options
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