A bursa is a fluid-filled sac that cushions an area of friction between tissues, such as tendon and bone. Bursae reduce friction between moving parts of the body, such as around the joints of the shoulder, elbow, hip, knee, and adjacent to the Achilles tendon in the heel.
The number varies, but most people have about 160 bursae throughout the body. Bursae are lined with special cells, called synovial cells, which secrete a fluid rich in collagen and proteins. This synovial fluid acts as a lubricant when parts of the body move. Inflammation of a bursa is referred to as bursitis.
What are causes of bursitis?
The most common causes of bursitis are repetitive motions (for example, repeated throwing of a ball), trauma (extensive kneeling or hitting your knee on a table), infection, and preexisting rheumatoid conditions.
Trauma causes inflammatory bursitis from repetitive injury or direct impact.
- Chronic bursitis: The most common cause of chronic bursitis is minor trauma that may occur to the shoulder (subdeltoid) bursa from repetitive motion, for example, throwing a baseball. Another example is prepatellar bursitis (in front of the knee) from prolonged or repetitive kneeling on a hard surface to scrub a floor or lay carpet.
- Acute bursitis: A direct blow (let's say you accidentally bang your knee into a table) can cause blood to leak into the bursa. This causes inflammation with pain as well as swelling.
Bursae close to the surface of the skin are the most likely to get infected with bacteria, a condition that is called septic bursitis. The most common bacteria to cause septic bursitis are Staphylococcus aureus or Staphylococcus epidermis. People with diabetes, alcoholism, certain kidney conditions, those with suppressed immune systems such as from cortisone medications (steroid treatments), and those with wounds to the skin over a bursa are at higher risk for septic bursitis. About 85% of septic bursitis occurs in men.
People with certain rheumatoid diseases such as gout and pseudogout can develop bursitis from crystal deposits. When these crystals form in a bursa, they cause inflammation leading to bursitis.
What are bursitis risk factors?
Risk factors for bursitis include repetitive activities, gout, pseudogout, rheumatoid arthritis, trauma, and skin infections.
What are bursitis symptoms and signs?
Bursitis causes pain and tenderness around the affected bone or tendon. The bursae sacs may swell, often making movement difficult. The most commonly affected joints are the shoulder, elbow, knee, and foot.
In the shoulder, the subacromial bursa (subdeltoid bursa) separates the supraspinatus tendon from the overlying bone and deltoid muscle. Inflammation of this bursa is usually a result of injury to surrounding structures, most commonly the rotator cuff. This limits the range of motion of the shoulder resulting in an "impingement syndrome." The condition causes pain in the side or front of the shoulder.
- Overhead lifting or reaching activities are uncomfortable.
- Pain is often worse at night.
- The shoulder will usually have decreased range of active motion and be tender at specific spots.
Bursitis of the tip of the elbow, olecranon bursitis, is the most common form of bursitis.
- The pain may increase if the elbow is bent because tension increases over the bursa.
- This bursa is frequently exposed to direct trauma (bumping your arm) or repeated motions from bending and extending the elbow (while painting, for example).
- Infection is common in this bursa.
- Bursitis in front of the kneecap (prepatellar): Swelling on the front of the kneecap can be caused by chronic trauma (as from kneeling) or an acute blow to the knee. Swelling may occur as late as seven to 10 days after a single blow to the area, usually from a fall. Prepatellar bursitis has also been called carpet-layer's knee, housemaid's knee, and clergyman's knee.
- Pes anserine bursitis: The pes anserine bursa is fan shaped and lies among three of the major tendons at the inner knee.
- This type of bursitis is most often seen in people with arthritis, especially overweight middle-aged women with osteoarthritis.
- The pain of anserine bursitis is typically produced when the knee is bent and is particularly troublesome at night. People often seek comfort in bed by sleeping with a pillow between their thighs.
- The pain can radiate to the inner thigh and mid-calf and usually increases on climbing stairs and at extremes of bending and extending.
- Pes anserine bursitis also occurs as an overuse or traumatic injury among athletes, particularly long-distance runners.
Retrocalcaneal bursitis occurs when the bursa under the Achilles tendon at the back of the heel becomes inflamed. This is commonly caused by local trauma associated with wearing a poorly designed shoe (often high heels) or prolonged walking. It can also occur with Achilles tendonitis.
Bursitis in this part of the body often occurs as an overuse injury in young athletes, ice skaters, and people starting new exercise programs, including walking or jumping. The pain is usually on the back of the heel and increases with passive extension or resisted flexion.
Ischiogluteal bursitis causes inflammation of the ischial bursa, which lies between the bottom of the pelvic bone and the overlying gluteus maximus muscle (one side of the buttocks). Inflammation can come from sitting for a long time on a hard surface or from bicycling. Ischiogluteal bursitis has also been called weaver's bottom because it is common from the positioning used in this occupation.
- The pain occurs when sitting and walking.
- There will be tenderness over the pubic bone, which may be made worse by bending and extending the leg.
- The pain may radiate down the back of the thigh.
- Direct pressure over the area causes sharp pain.
- The person may hold the painful buttock elevated when sitting.
- The pain is worse when person is lying down and the hip is passively bent.
- The person may have difficulty standing on tiptoe on the affected side.
The iliopsoas bursa is the largest in the body and lies in front of, and deep to, the hip joint. Bursitis here is usually associated with hip problems such as arthritis or injury (especially from running).
- The pain of iliopsoas bursitis radiates down the front and middle areas of the thigh to the knee and is increased when the hip is extended and rotated.
- Extension of the hip during walking causes pain so the person may limit the stride on the affected side and take a shorter step.
- There may be tenderness in the groin area.
- Sometimes a mass may be felt resembling a hernia. The person may also feel numbness or tingling if adjacent nerves are compressed by the inflamed bursa.
The trochanteric bursa, at the outer thigh over the hip, can become inflamed to cause trochanteric bursitis. Trochanteric bursitis is very common and occurs most frequently in overweight, middle-aged women.
- Trochanteric bursitis causes deep, aching hip pain along the side of the hip that may extend into the buttocks or to the side of the knee.
- Pain is aggravated by activity, local pressure, or stretching.
- Pain is often worse at night and can make it difficult to sleep on the involved side.
Bursitis: Treatments for Hip, Knee Shoulder and More
What are symptoms of ischial bursitis?
Ischial bursitis is inflammation of the bursa that separates the gluteus maximus muscle of the buttocks from the underlying bony prominence of the bone that we sit on, the ischial tuberosity. Ischial bursitis is a form of bursitis that is usually caused by prolonged sitting on hard surfaces that press against the bones of the bottom or mid-buttocks.
When should someone seek medical care for bursitis?
Because bursitis can be infectious and needs to be treated with antibiotics, it is best to see a doctor the first time you recognize symptoms.
If the pain is not getting better with home care, your doctor may be able to offer some alternatives such as a cortisone injection.
Fever is a definite sign to seek immediate medical care because it may signify infection. Heed other warning signs of infection such as constant warmth or redness around the joint or severe tenderness. Skin infections around the area (cellulitis) may mean that the bursa is infected as well.
What specialists diagnose and treat bursitis?
Bursitis is treated by primary care physicians, including family medicine doctors, general practitioners, and internists, as well as orthopedists, physiatrists, and rheumatologists.
exams do health care professionals use to diagnose bursitis?
- History: The doctor will usually take a detailed history about the onset of symptoms and will want to know what movement or activity makes you feel more or less pain. You will need to report other medical problems you may have.
- Fluid removal: The doctor may remove fluid from the bursa with a needle and send it to the lab for analysis. This analysis will help determine if the bursitis is due to an infection or rheumatoid condition or trauma). Bursitis in the knee and elbow are especially prone to infection. Removal of the fluid might alleviate some of the pain.
- X-rays: They are usually not helpful, but the doctor may get them if any other disease is suspected such as a fracture or dislocation. MRI and CT scans are obtained only to exclude other causes.
- Blood testing: The doctor may order blood tests to rule out infection or other conditions such as rheumatoid arthritis.
What are bursitis treatments?
The doctor will probably recommend home care with P-R-I-C-E-M: protection, rest, ice, compression, elevation, and medications (discussed below).
there bursitis home remedies?
The treatment for bursitis can be remembered with the following memory device: P-R-I-C-E-M.
- Protection includes padding especially for bursae close to the surface of the skin on the ankles and knees.
- Relative rest of the affected area if possible may help symptoms. Choose alternate types of exercise activities that eliminate painful motions. Swimming may help rather than hurt.
- Ice is very effective in reducing inflammation and pain. Small ice packs, such as packages of frozen vegetables, applied to the area for 10 minutes at least twice a day may help decrease inflammation.
- Compression and elevation are helpful when it is feasible to compress the area. An elastic bandage can be applied (especially to knees and elbows). Keep the area elevated above the heart to keep blood from pooling there.
- Medications such as aspirin or ibuprofen (Advil) can be helpful to reduce inflammation and pain. Consult your doctor before taking these if you are on any blood-thinning medications or have a history of stomach ulcers or kidney disease.
What is the medical treatment for bursitis?
If your bursitis is not infectious, the doctor may inject the bursa with a corticosteroid to reduce inflammation.
If your bursitis is infectious, the bursa will be drained with a needle. The doctor will prescribe antibiotics to be taken in pill form. If the infection is very serious, does not respond to oral antibiotics, or if your immune system is weakened for another reason, you may be admitted to the hospital for IV antibiotics. Most causes of infectious bursitis, however, can be managed safely at home. Occasionally, a surgical operation to remove the bursa can be required.
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How often is follow-up needed after treatment of bursitis?
After you leave the doctor's office, try to change whatever caused the bursitis in the first place. Wear different shoes. Use kneepads when kneeling for activities or work.
Rest the area and apply ice at least twice a day, keeping the area elevated when possible.
Schedule a follow-up visit with your doctor in one week. If your bursitis is infectious, a follow-up visit in three to four days is appropriate for reevaluation and possible fluid removal.
there a way to prevent bursitis?
If a certain activity causes you to develop bursitis, then limit that activity or use protective measures. Use kneepads or cushioning for gardening and scrubbing floors. Workers such as plumbers, roofers, and carpet layers should wear knee protection. Choose more appropriate shoes or cushion the ankles with pads.
You can improve your flexibility and strengthen muscles involved in joint motion through rehabilitative exercise.
Be concerned about muscle tone if you have bursitis that tends to return. A physical rehabilitation program can guide you in the proper exercises to strengthen weak muscles.
What is the prognosis for bursitis?
Most people respond to therapy in three to four days and can follow up with their doctor in a week. If the bursitis is infectious, however, the area may have to be drained with a needle every three to five days until the infectious fluid does not return.
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Media file 1: Acute infectious bursitis (septic bursitis) of the elbow. Courtesy of Christopher Kabrhel, MD.
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Media file 2: Infectious bursitis (septic bursitis) of the elbow. Courtesy of Christopher Kabrhel, MD.
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Media file 3: Infectious bursitis. Note the swelling at the elbow and redness of the skin. Courtesy of Christopher Kabrhel, MD.
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Medically Reviewed on 4/17/2018
Firestein, Gary S., et al. Kelley's Textbook of Rheumatology, Ninth Edition. China: Elsevier Health, 2012.