Osteoarthritis is the most common type of arthritis in the UK, and the knee is one of the joints it most often affects. In osteoarthritis the protective cartilage on the ends of the bones breaks down, which can cause pain, swelling and difficulty moving the joint. The NHS notes that it does not necessarily get worse over time, and that symptoms can sometimes gradually improve.
Common symptoms
- Pain that is worse the more you use the knee
- Stiffness and difficulty moving the joint
- Swelling or tenderness
- A grating or crackling sensation when the knee moves
Symptoms vary a great deal between people. For some they are mild and come and go; for others they make everyday activities difficult.
How it is diagnosed
NICE guidance (NG226) advises that osteoarthritis can be diagnosed clinically, without imaging, in people aged 45 or over who have activity-related joint pain and either no morning stiffness or morning stiffness lasting no longer than 30 minutes. Imaging is not routinely needed unless there are atypical features, such as recent injury, prolonged morning stiffness, rapid worsening or a hot swollen joint.
When to see a specialist
Many people manage knee arthritis well for years. NICE suggests considering referral for joint replacement when symptoms such as pain, stiffness or reduced function are substantially affecting quality of life and non-surgical treatment has not worked or is not suitable. NICE also advises that age, sex, smoking, other health conditions or body weight should not, by themselves, exclude someone from referral.
Non-operative options
NICE describes therapeutic exercise and weight management (where relevant), together with information and support, as the core treatments for osteoarthritis.
- Therapeutic exercise tailored to you — local muscle strengthening and general fitness, ideally with physiotherapy guidance
- Weight loss if you are living with overweight — NICE notes that any amount is likely to help, and that losing 10% of body weight is likely to be better than 5%
- Topical anti-inflammatory gels, which NICE recommends offering for knee osteoarthritis, with other medicines used at the lowest effective dose for the shortest possible time
- Walking aids, such as a stick, when they help
- Steroid injections in selected cases — NICE advises these give short-term relief of 2 to 10 weeks
NICE recommends against some treatments for osteoarthritis, including acupuncture, hyaluronan injections and arthroscopic washout or debridement.
Surgical options
When arthritis is advanced and symptoms remain hard to live with, the options include total or partial knee replacement. Where arthritis is confined to the inner (medial) compartment of the knee, NICE recommends offering a choice between partial and total knee replacement and discussing the benefits and risks of each. The NHS also describes other operations, such as osteotomy, that may suit a small number of people.
Questions worth asking
- How much is the arthritis affecting my daily life, and what matters most to me?
- Have I had a fair trial of exercise, weight management and simple pain relief?
- Is the arthritis in one part of the knee or throughout it?
- What would recovery look like for someone with my work and activities?
The right choice depends on your history, examination and imaging. If you would like a clear assessment, you can arrange a private consultation or discuss a referral with your GP.
Frequently asked questions
Do I need an X-ray to diagnose knee arthritis?
Not usually. NICE advises that osteoarthritis can be diagnosed clinically in people aged 45 or over with activity-related joint pain and little or no morning stiffness. Imaging is used when there are atypical features or another diagnosis is suspected.
Will exercise make my knee arthritis worse?
NICE advises that joint pain may increase when you start therapeutic exercise, but that regular, consistent exercise is beneficial and long-term adherence improves pain, function and quality of life.
Do steroid injections help knee arthritis?
They can be considered when other treatments are ineffective or unsuitable, or to support exercise. NICE advises they provide only short-term relief, of 2 to 10 weeks.
When should I think about knee replacement?
NICE suggests considering referral when symptoms substantially affect your quality of life and non-surgical treatment has not worked or is not suitable.
References
- NHS. Osteoarthritis: overview. https://www.nhs.uk/conditions/osteoarthritis/
- NICE. Osteoarthritis in over 16s: diagnosis and management (NG226), recommendations. National Institute for Health and Care Excellence, 2022. https://www.nice.org.uk/guidance/ng226/chapter/Recommendations
- NHS. Alternatives to a knee replacement. https://www.nhs.uk/conditions/knee-replacement/alternatives/
- NICE. Joint replacement (primary): hip, knee and shoulder (NG157), recommendations. National Institute for Health and Care Excellence, 2020. https://www.nice.org.uk/guidance/ng157/chapter/Recommendations