Symptoms of Knee Pain

Knee pain looks different depending on the cause. The location and the pattern are useful clues.

Common symptoms

• Pain in the front, inside, outside or back of the knee
• Stiffness, especially in the morning or after sitting
• Swelling or a feeling of fullness
• Warmth or redness
• Clicking, grinding or popping
• Weakness or a feeling that the knee gives way
• Difficulty straightening or bending the knee, or climbing stairs

Clues from the pattern

• Pain on stairs or after sitting, around the kneecap: patellofemoral pain
• Pain with brief stiffness, worse with activity: osteoarthritis
• Pain and swelling soon after a twist or a pop: ligament or meniscus injury
• Locking or catching: meniscus tear or loose fragment
• Sudden hot, red, very painful knee: gout or infection
• Swelling and morning stiffness over an hour: inflammatory arthritis
• Pain on the outer side in runners: iliotibial band syndrome

See a doctor soon if

• Pain lasts more than 2 weeks
• The knee is swollen, stiff or unstable
• Pain wakes you at night or limits daily activity

Emergency signs: urgent care or call 112

• A hot, red, very painful swollen knee with fever
• Not able to put weight on the leg after an injury
• A knee that is locked and will not straighten
• Visible deformity after injury
• Calf swelling, pain or redness, or chest pain and breathlessness

Key point

A hot swollen knee with fever may be an infection and needs same-day care.

Before your appointment

Note when the knee pain began, where it hurts, and whether there was a fall or twist. Describe swelling, stiffness, locking, giving way, clicking and what makes it better or worse. List all medicines, painkillers, supplements and herbal products. Mention fever, other joint pain, gout and past knee problems. Bring earlier X-rays or reports and your usual shoes. Ask about tests, exercise, safe pain relief and when surgery is considered. Seek urgent care for a hot swollen knee with fever or inability to bear weight, or call 112 for severe symptoms.