Knee Bursitis

Knee bursitis is inflammation of a fluid-filled cushion near the knee that can cause local swelling, tenderness, and pain. A bursa reduces rubbing between skin, tendons, muscles, and bone. The prepatellar bursa in front of the kneecap is often affected, but bursitis can also occur beside or below the knee.

The swelling is usually local rather than spread through the whole leg. Infection, repeated pressure, a blow, or another inflammatory condition can produce similar symptoms, so assessment is useful when swelling persists.

Knee bursitis commonly presents with a tender, localised swelling and pain that worsens with kneeling, bending, or pressure. The skin may feel warm, and movement can be uncomfortable. See [Knee Pain](/symptoms/knee-pain/) and [Knee Swelling](/symptoms/knee-swelling/) for related symptom information.

Fever, spreading redness, marked warmth, drainage, or feeling unwell can indicate infection and needs prompt medical review. Sudden inability to bear weight after an injury should also be assessed urgently.

Repeated kneeling, crawling, leaning on the knee, or frequent bending can irritate a bursa. A direct impact may trigger swelling, while a cut or puncture can allow bacteria to enter. Gout, rheumatoid arthritis, and other inflammatory conditions can also affect a bursa.

Symptoms may develop gradually after repeated pressure or appear soon after an impact. Removing the aggravating pressure can allow irritation to settle, but an infected bursa can worsen without treatment. Recurrent episodes often signal that kneeling technique, equipment, activity load, or an underlying condition needs review.

Frequent kneeling at work or during hobbies, contact sports, recent skin injury, and inflammatory disease can increase risk. Reduced mobility may also lead to repeated pressure on the same area. A risk factor raises susceptibility but does not confirm that bursitis is the cause of knee swelling.

A clinician examines the swelling, skin temperature, tenderness, and knee movement, then asks about pressure, injury, wounds, and inflammatory symptoms. If infection or another cause is suspected, fluid may be sampled from the bursa for testing. Imaging is used when bone, tendon, or joint problems need clarification.

Care depends on whether the bursa is irritated, inflamed by another disease, or infected. Rest from kneeling, cushioning, cold packs, and gradual return to activity may help. A clinician may recommend [Anti-Inflammatory Medication](/treatments/non-surgical-orthopedics/anti-inflammatory-medication/) when suitable.

Persistent swelling may be treated with [Joint Aspiration](/treatments/non-surgical-orthopedics/joint-aspiration/), particularly when fluid needs testing or removal. Recurrent cases that do not respond to other care may lead to discussion of [Bursa Removal](/treatments/reconstructive-orthopedic-surgery/bursa-removal/). Infection requires clinician-directed treatment rather than self-care alone.

Use a padded surface or a kneeling aid for tasks that cannot be avoided, and change position regularly. Keep any skin break clean and covered. Return to bending and sport in stages once tenderness and swelling are settling, using symptoms during the following day to guide the pace.

Untreated infection can spread beyond the bursa and make a person unwell. Ongoing pressure may cause recurrent swelling, while guarding the knee can reduce strength and confidence with movement. Persistent or repeated symptoms warrant review for infection, inflammatory disease, or a different knee problem.

Limit prolonged kneeling, use cushioning, and vary tasks where possible. Protect the skin from scrapes and clean wounds promptly. Build activity gradually and address inflammatory conditions with the appropriate clinician. These measures reduce irritation but cannot prevent every episode.

See a clinician if swelling persists, returns, restricts movement, or follows a wound. Seek prompt care for fever, spreading redness, pus, severe warmth, or rapidly increasing pain and swelling. An orthopaedic clinician, rheumatologist, or physiotherapist may be involved depending on the suspected cause.