What Is Knee Bursitis?

Knee bursitis is irritation or inflammation of a small fluid-filled sac called a bursa. Bursae reduce friction between the skin, tendons, muscles and bones around your knee. An irritated bursa may become swollen, warm and tender, particularly when you kneel, bend your knee or press on the area.

Knee bursitis usually causes local symptoms rather than pain throughout the whole joint. However, its symptoms can overlap with other causes of knee pain. The location of the swelling and tenderness often helps identify which bursa is involved.

Several knee bursae can become irritated, including the prepatellar, superficial infrapatellar, deep infrapatellar and pes anserine bursa. The suprapatellar bursa can also become distended, although it often communicates with the knee joint and may be associated with broader joint swelling.

Where Does Knee Bursitis Occur?

The symptom location varies according to the affected bursa.

Prepatellar Bursitis

Prepatellar bursitis causes swelling directly over the kneecap. It is often linked with repeated kneeling or a direct impact. It is sometimes called housemaid’s knee, carpet layer’s knee or carpenter’s knee.

Infrapatellar Bursitis

Infrapatellar bursitis causes pain or swelling below the kneecap. A superficial bursa lies between the skin and patellar tendon, while a deeper bursa lies behind the tendon. Symptoms can sometimes resemble patellar tendinopathy.

Pes Anserine Bursitis

Pes anserine bursitis causes pain and tenderness along the inner upper shin, below the knee joint. It may become more noticeable with stairs, running or repeated knee loading. Read more about pes anserine bursitis and tendinopathy.

What Causes Knee Bursitis?

Repeated compression or friction is a common trigger. Knee bursitis may develop after prolonged kneeling, a direct blow, a fall onto the knee or repeated pressure during work, gardening, sport or exercise.

In some people, a rapid increase in activity, repeated knee loading or irritation of nearby tendons may continue to aggravate the area. Medical conditions can also increase the risk. These include gout, rheumatoid arthritis, diabetes and other conditions that affect the immune system.

Bacteria can enter a superficial bursa through broken skin, a puncture, an abrasion or an infected area nearby. This causes septic bursitis and requires medical treatment.

What Are the Symptoms of Knee Bursitis?

Common symptoms include local swelling, tenderness, warmth and pain when pressure is placed on the affected bursa. Some people notice stiffness or discomfort when they bend or straighten the knee. Others have visible, soft swelling without much pain.

Prepatellar bursitis often causes a rounded swelling over the kneecap. Pes anserine bursitis usually causes a smaller tender area on the inner side of the upper shin. Infrapatellar bursitis causes symptoms below the kneecap.

Knee bursitis may occur alongside other problems, including patellofemoral pain, tendon irritation or knee arthritis. A proper assessment can help distinguish between these conditions.

Can Knee Bursitis Cause Pain When Kneeling?

Yes. Pain with kneeling is a common feature of prepatellar and superficial infrapatellar bursitis. Direct pressure compresses the swollen bursa between the floor and the underlying kneecap or patellar tendon.

You may also notice a soft lump, local warmth or tenderness. Protective knee pads and temporary changes to work or exercise can reduce direct pressure while the irritation settles.

Could Knee Bursitis Be Infected?

A knee bursa can become infected. This is called septic bursitis. It most often affects superficial bursae, including the prepatellar bursa, because bacteria can enter through damaged skin.

Seek prompt medical assessment if you notice:

• Rapidly increasing redness, warmth or swelling
• A cut, graze, puncture or wound near the swollen area
• Fever, chills or feeling generally unwell
• Marked tenderness or rapidly worsening pain
• Pus or fluid draining through the skin
• Significant swelling when you have diabetes or reduced immunity

Fever is not always present with septic bursitis. Therefore, do not wait for a fever if the knee is becoming increasingly hot, red or swollen. Suspected infection requires medical assessment and may need fluid testing and antibiotics. Physiotherapy is not the main treatment for an infected bursa.

How Is Knee Bursitis Diagnosed?

A physiotherapist or doctor will ask when your symptoms started, what activities aggravate them and whether you have had a fall, wound or period of repeated kneeling. They will examine the location and size of the swelling, knee movement, tenderness and surrounding skin.

The assessment also checks for other causes of swelling or pain, such as a joint effusion, cellulitis, gout, tendon injury, fracture, meniscus injury or arthritis.

Many cases can be identified through the history and examination. An ultrasound may help show fluid within a bursa and distinguish it from nearby tendon or soft-tissue problems. An X-ray or MRI may be considered after trauma or when the diagnosis remains unclear.

If infection or gout is suspected, a doctor may recommend aspiration. This involves removing a sample of fluid for laboratory analysis.

Knee Bursitis Treatment

Knee bursitis treatment depends on the affected bursa, the cause of the irritation and whether infection is possible. Early treatment usually aims to reduce pressure on the area while maintaining comfortable knee movement.

Management may include:

• Temporarily reducing kneeling or activities that compress the bursa
• Using protective knee pads for unavoidable kneeling
• Applying a wrapped cold pack for short periods if it feels helpful
• Maintaining comfortable bending, straightening and walking
• Gradually restoring strength and activity as symptoms settle
• Using medication only as advised by a doctor or pharmacist
• Addressing gout, inflammatory arthritis or infection when relevant

Avoid repeatedly pressing, rubbing or trying to drain the swelling yourself. This can irritate the area or introduce infection.

A medical practitioner may consider aspiration when marked swelling persists, when fluid analysis is needed or when infection or crystal-related disease is suspected. Injection is not a routine first treatment for every case. A corticosteroid injection should not be given when infection is possible.

Surgery is uncommon. It may be considered for persistent, recurrent or infected bursitis that has not responded to appropriate medical treatment. You can also read about broader bursitis treatment options.

Can Physiotherapy Help Knee Bursitis?

Physiotherapy may help when non-infectious knee bursitis is linked with repeated loading, reduced movement, weakness or difficulty returning to work, exercise or sport.

Your physiotherapist may assess:

• Which bursa appears to be involved
• The activities and positions that compress the area
• Knee and hip movement
• Lower-limb strength and control
• Work, sport and training demands
• Whether medical review or imaging is needed

Treatment may include activity modification, advice about padding, a gradual return to kneeling, movement exercises and progressive strengthening. Taping or hands-on treatment may help selected associated problems, but the main priority is usually reducing repeated bursal compression and restoring normal function.

A personalised program of rehabilitation exercises may help if weakness, reduced capacity or altered loading is contributing to repeated flare-ups.

How Long Does Knee Bursitis Take to Recover?

Mild, non-infectious knee bursitis may improve over several weeks when repeated pressure is reduced early. Recovery can take longer when the area remains compressed, symptoms have been present for months or another condition is contributing.

Visible swelling may remain after pain has eased. Persistent swelling does not always mean that the knee is being damaged, although it should be assessed if it is enlarging, painful, hot or affecting activity.

Recovery time also depends on the type of bursitis. Infection, gout, marked fluid accumulation or repeated workplace kneeling may require additional medical or workplace management.

Should You Rest or Keep Moving?

Avoid or modify the activity that directly aggravates the bursa, particularly kneeling or sustained pressure. However, complete rest is rarely required for uncomplicated knee bursitis.

Comfortable walking and gentle knee movement can usually continue if they do not increase the swelling or pain. Your return to deeper bending, kneeling, running or loaded exercise should be gradual and guided by your symptoms.

How Can You Prevent Knee Bursitis?

You can reduce the risk of repeated knee bursitis by limiting prolonged kneeling, using well-padded knee protection and taking regular breaks from pressure-based tasks.

Other useful steps may include:

• Increasing work, sport and exercise loads gradually
• Changing kneeling positions regularly
• Keeping cuts and grazes clean and covered
• Avoiding exercise through rapidly increasing swelling
• Building knee and hip strength for demanding activities
• Managing gout, arthritis or other relevant health conditions

A physiotherapist can help identify whether training load, strength, movement or work demands are contributing to repeated symptoms.

Knee Bursitis FAQs

What is the best treatment for knee bursitis?

The best treatment depends on the cause. Most non-infectious cases need reduced pressure, temporary activity modification and comfortable movement. Protective padding and a gradual return to normal activity may help. Hot, red or rapidly worsening swelling requires medical assessment because infection needs different treatment.

How long does knee bursitis take to recover?

Mild cases may improve within several weeks when repeated pressure is removed. Long-standing bursitis, continued kneeling, marked swelling or an associated medical condition can extend recovery. A physiotherapist or doctor can assess persistent symptoms and check whether another knee problem is involved.

Can physiotherapy help knee bursitis?

Physiotherapy may help non-infectious knee bursitis by identifying aggravating loads, maintaining movement and improving lower-limb strength. It may also guide a safe return to kneeling, work, exercise or sport. Suspected infection requires medical care rather than physiotherapy treatment alone.

Can a swollen knee bursa be drained?

A doctor may aspirate a swollen bursa to test for infection or crystals, or to manage marked fluid accumulation in selected cases. Aspiration is not required for every presentation and the fluid can return. Do not puncture or attempt to drain the bursa yourself.

Should I rest or move with knee bursitis?

Reduce activities that directly compress or irritate the bursa, especially kneeling. Comfortable walking and gentle knee movement can usually continue if they do not worsen symptoms. Gradually restore more demanding activity as swelling, pain and tenderness improve.

When should I seek urgent help for knee bursitis?

Seek prompt medical care if the knee becomes rapidly more red, hot, swollen or painful, particularly after a skin wound. Fever, chills, drainage, feeling unwell or reduced immunity also increase concern about infection. Fever may be absent, so worsening local signs still matter.

What to Do Next for Knee Bursitis

Arrange an assessment if knee swelling or tenderness persists, repeatedly returns or affects walking, kneeling, work or exercise. A physiotherapist can assess whether the symptoms fit knee bursitis, identify contributing loads and guide an appropriate recovery plan.

If the swelling is hot, red, rapidly worsening or associated with a wound, fever or feeling unwell, seek prompt medical assessment rather than waiting for a routine physiotherapy appointment.

Related Knee Bursitis Articles

• Bursitis
• Bursitis Treatment
• Pes Anserine Bursitis and Tendinopathy
• Patellar Tendinopathy
• Patellofemoral Pain
• Knee Arthritis
• Knee Pain FAQs

References

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2. Darrieutort-Laffite C, Coiffier G, Aïm F, et al. 2023 French recommendations for diagnosing and managing prepatellar and olecranon septic bursitis. Joint Bone Spine. 2024;91(2):105664. doi:10.1016/j.jbspin.2023.105664
3. McGill KC, Patel R, Chen D, Okwelogu N. Ultrasound-guided bursal injections. Skeletal Radiol. 2023;52:967-978. doi:10.1007/s00256-022-04153-y
4. Rishor-Olney CR, Taqi M, Pozun A. Prepatellar bursitis. In: StatPearls. StatPearls Publishing; updated January 4, 2024.