Bursitis may be a word you only heard spoken by the elderly but, in fact, 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.
What exactly is this problem? Bursitis is the inflammation of a bursa. A bursa is a sac made of thin, slippery tissue. Bursae (plural) occur in the body wherever skin, muscles, or tendons need to slide over bone. Bursae are lubricated with a small amount of fluid inside that helps reduce friction from the sliding parts. They can also be found between muscle and fibrous bands of connective tissue.
Four main areas of bursitis are the focus of this article: the knee, elbow, hip, and heel. Causes of bursitis include trauma, inflammation, and infection.
The diagnosis is made based on patient history, symptoms, and special tests. The problem must always be sorted out carefully as the same symptoms can occur with tumors, arthritis, fractures, tendinitis, and nerve damage. Sometimes bursitis is a secondary problem caused by some other disease process such as gout or sarcoidosis.
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. This usually 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. For example, 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. Why not? Because there isn't much of a blood supply to the bursa.
As mentioned, the patient's history and symptoms are often a clear indication of the problem. The real challenge is in determining whether or not there is an infectious process going on. Sometimes the physician has to aspirate the bursa. Aspiration is a way to remove some of the fluid for analysis. A very thin needle is inserted into the bursa to suction out the fluid.
Imaging studies such as MRIs are also helpful. X-rays may be taken first to rule out arthritis and fractures. And for each location (elbow, knee, hip, heel), there are special tests the examiner (e.g., physician, physiotherapist) can apply to confirm the presence of a bursitis. Most of these tests involve some type of movement or position that compresses (pushes on) the bursa, thus reproducing the symptoms.
Treatment is usually conservative (nonoperative) care. Rest, activity modification, and medications such as antiinflammatories (for pain and swelling) or antibiotics (for infection) are the main management tools. Stretching the soft tissues around the bursa may help. In the case of a heel bursitis, a change in shoe wear may be recommended. The idea is to find a shoe that doesn't rub against the heel over the bursa.
Surgery to remove the bursa (called bursectomy) is usually reserved for patients who do not respond to nonsurgical care. There is always a risk of additional problems or complications with any surgery, so this is not the first step in treatment. But it has its place when all else fails.
Other surgical techniques depend on the location of the bursa. For example, in the hip area, it may be necessary to remove a portion of bone or release some of the involved soft tissues (e.g., the iliotibial band).
In the heel, an osteotomy of the bone may help change the alignment and take pressure off the bursa. An osteotomy is the removal of a tiny wedge-shaped piece of bone. Collapsing the remaining edges of bone together (called a closing wedge osteotomy) rotates the calcaneus (heel) bone just enough to remove pressure from the bone and stop the bursitis.
For anyone with bursitis at one of these four main areas (elbow, knee, hip, or heel), this is a good review article. The authors provide a nice summary of the condition, drawings to explain the problem, and photos of MRIs to give a visual description. The diagnosis and management for each type (infectious, traumatic, inflammatory) and each location are also included.
Reference: Daniel L. Aaron, MD, et al. Four Common Types of Bursitis: Diagnosis and Management. In Journal of the American Academy of Orthopaedic Surgeons. June 2011. Vol. 19. No. 6. Pp. 359-367.