Bursitis is not an age-dependent condition. This condition can affect people of all ages. Older adults are the most likely to develop pain, swelling, and tenderness around a joint from bursitis. But younger folks can be affected, too.
Causes of bursitis include trauma, inflammation, and infection. When trauma is the cause, it may be the result of a direct blow or a fall onto the knee, elbow, hip, or heel that damages the bursa. So you see how this can happen to anyone.
An injury can causes bleeding into the bursa sac because the blood vessels in the tissues that make up the bursa are damaged and torn. In the skin, this would simply form a bruise, but in a bursa blood may actually fill the bursa sac. This causes the bursa to swell up like a rubber balloon filled with water.
The blood in the bursa is thought to cause an inflammatory reaction. The walls of the bursa may thicken and remain thickened and tender even after the blood has been absorbed by the body. This thickening and swelling of the bursa is what we refer to as bursitis.
The bursae can become irritated and inflamed in other ways. For example, in the case of prepatellar (knee) bursitis, repeated injury can lead to irritation and thickening of the bursa over time. People who work on their knees, such as carpet layers and plumbers, can repeatedly injure the prepatellar bursa (pad in front of and behind the patellar tendon just below the knee cap). This repeated injury can lead to irritation and thickening of the bursa over time.
When infection is the cause of bursitis, it is usually from a staph or strep infection. The bacteria enter the body close to the affected joint through a cut or small opening in the skin. A minor skin infection of the skin over the bursa can spread down into the bursa. In this case, instead of blood or inflammatory fluid in the bursa, pus fills it. The area around the bursa becomes hot, red, and very tender.
Bacteria can travel to the joint via the bloodstream but it’s not thought that this is the way infectious bursitis develops. That’s because there isn’t much of a blood supply to the bursa.
Age-related changes in the soft tissues certainly can lead to bursitis. But bursitis can also be associated with some other systemic diseases such as sarcoidosis (and inflammatory condition) or gout. Usually, the physician who diagnoses the problem can see a pattern that might suggest the underlying cause. If you’re interested, ask your doctor what he or she thinks might be the cause of your bursitis.