Knee pain

Category: Muscles, Bones & Joints · All muscles & joints symptoms

What it can feel like

Knee pain is pain in or around the knee — front, sides, back, or deep inside — often with swelling, stiffness, clicking or giving way. The knee is the largest joint and the most commonly injured; the pattern of onset (injury versus gradual) and the company it keeps guide diagnosis.

Possible causes

A symptom can have many causes, and most are not serious. The lists below group conditions this symptom can be associated with — common causes first. They are possibilities to discuss with a clinician, not a diagnosis.

Common causes

Knee pain can be associated with strains and sprains, cartilage (meniscus) tears, tendon irritation at the kneecap, inflammation of the fluid sacs, and osteoarthritis, the wear-related arthritis that becomes common with age.

Other possible causes

Knee pain can also be associated with inflammatory arthritis such as rheumatoid arthritis or gout, infection inside the joint (an emergency), ligament ruptures after twisting injuries, and referred pain from the hip — a point that matters in children and teenagers.

Red flags — when to seek help promptly

A hot, swollen, painful knee with fever — emergency (possible joint infection)
Knee pain after injury with inability to bear weight or a locked knee
Knee pain with rapid swelling within hours of injury (blood inside the joint)
A child or teenager with knee pain and a limp — the hip must be checked
Knee pain with unexplained weight loss or constant night pain

What a clinician may do

A clinician will examine the knee's movement, stability, swelling and tender points, and examine the hip as well. X-rays show arthritis and fractures; MRI follows suspected internal derangement in selected cases. Exercise-based physiotherapy is central for most chronic knee pain.

Watch: related videos

Examination and clinical videos from the MedicalVideos.com library relevant to this symptom. Some clinical footage is graphic — that is the nature of a medical video library.

▶ WatchKnee painWatch on MedicalVideos.com ▶ WatchKnee pain symptoms treatment and preventionWatch on MedicalVideos.com ▶ WatchKnee pain diagnosis and exercisesWatch on MedicalVideos.com

Related guides on MedicalVideos.com

Frequently asked questions

Why does knee pain sometimes come from the hip?

The hip and knee share nerve supply, so hip disease — including the slipped growth plate of teenagers — commonly presents as knee pain with a normal knee. That is why a painful knee with a limp in a young person always earns a hip examination.

Do I need a scan to diagnose arthritis?

Osteoarthritis is usually diagnosable from the story and examination, and X-rays are used when the picture is unclear or surgery is planned. Scan severity matches pain severity poorly — strong legs and good muscle support help pain more than most interventions.

Related symptoms — Muscles, Bones & Joints

A joint that locks or gives way Aching and stiffness in the shoulders and hips Aching muscles Ankle pain Back pain Elbow pain

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Please note: This page is educational information about a symptom. A symptom alone cannot diagnose any condition, and the causes listed here are possibilities, not a diagnosis. If you are worried about a symptom — especially one that is new, severe, getting worse or not going away — please see your own clinician, who can examine you and arrange tests. In an emergency, call your local emergency number.