Bursitis happens when the bursa is inflamed. The burse acts as a cushion between bones, tendons, joints and muscles - bursae are fluid-filled sacs (the plural of bursa is bursae). People with bursitis will feel pain at the site of inflammation. The medical word "bursa" comes from the Latin bursa, meaning a purse, which is what a bursa resembles.
About the bursae
There are about 160 bursae in the human body. These little, fluid-filled sacs cushion pressure and lubricate points between our bones, tendons, and muscles near our joints. The bursae are lined with synovial cells. Synovial cells produce a lubricant that reduces friction. This cushioning and lubrication allows our joints to move easily. When a person has bursitis - inflammation of the bursa - movement or pressure is painful.
Parts of the body affected by bursitis
The shoulder area can commonly be affected by bursitis.
Any bursa can become affected; however, the following are the most common places where bursitis may occur:
As many cases of bursitis are mild, lots of people with bursitis will sit it out or self treat and never see a doctor about it. It is therefore hard to know how common it is. GPs (general practitioners, primary care physicians) in the UK say that about 1 in every 200 patient visits are because of bursitis.
Causes of bursitis
Bursitis can be caused by an injury, an infection, or a pre-existing condition in which crystals can form in the bursa.
An injury can irritate the tissue inside the bursa and cause inflammation. Doctors say that bursitis caused by an injury usually takes time to develop. The joints, tendons, or muscles that are near the bursae may have been overused. Most commonly, injury is caused by repetitive movements.
Below are some examples of causes of bursitis:
- Tennis elbow - bursitis of the elbow is often termed tennis elbow. It is a common problem among tennis players and golfers. Repetitive bending of the elbow can eventually lead to injury and inflammation.
- Clergyman's knee - repeated kneeling can cause injury and eventual swelling to the bursae in the knee area.
- Shoulder - caused by repeated overhead lifting or reaching upwards.
- Ankle - injury to the ankle can be caused by walking too much and with the wrong shoes. Bursitis of the ankle is also common among ice skaters and athletes.
- Buttocks - the bursae in that area can become inflamed after sitting on a hard surface for a long time, such as on a bicycle.
- Hips - some long-distance runners, and also middle distance runners and sprinters if they train a lot can develop hip bursitis.
- Thigh - this can be caused by stretching.
Bursitis can also be caused by a hard blow to the area.
Infection that causes bursitis tends to be in bursae that are nearer the surface of the skin, such as those near the elbow. A cut on the skin is an opportunity for the bacteria to get in. Most healthy people would not be affected by opportunistic bacteria trying to get in through the skin. However, people with weakened immune systems, such as those with diabetes, HIV/AIDS, Cancer (receiving chemotherapy or radiotherapy), as well as people taking steroids, and heavy consumers of alcohol.
People with certain health conditions are more prone to the formation of crystals inside the bursa. The crystals irritate the bursa and make it swell. The conditions that may cause this include gout, rheumatoid arthritis, and scleroderma.
Symptoms of bursitis
A person with bursitis can have one or more of the following symptoms:
- Pain - the pain increases with movement or pressure
- Tenderness is felt even without movement
- Loss of movement
If the bursitis is caused by an infection it is called Septic Bursitis. The patient with septic bursitis may have the following additional symptoms:
- The affected area is red
- The affected area feels hot when touched
On the next page we look at the diagnosis of bursitis, common treatments for bursitis and how to prevent it occurring in the first place.