What is bursitis?
A bursa is a closed fluid-filled sac that functions as a gliding surface to reduce friction between tissues of the body. Bursae is plural for bursa. The major bursae are located adjacent to the tendons near the large joints, such as the shoulders, elbows, hips, and knees. When a bursa becomes inflamed, the condition is known as bursitis. Most commonly, bursitis is caused by local soft tissue trauma or strain injury, and there is no infection (aseptic bursitis). On rare occasions, the bursa can become infected with bacteria. This condition is called septic bursitis.
What is knee bursitis?
The knee joint is surrounded by three major bursae. At the tip of the knee, over the kneecap bone, is the prepatellar bursa. This bursa can become inflamed (prepatellar bursitis) from direct trauma to the front of the knee. This commonly occurs when maintaining a prolonged kneeling position. It has been referred to as “housemaid’s knee,” “roofer’s knee,” and “carpet layer’s knee,” based on the patient’s associated occupational histories.
What are causes of knee bursitis?
Bursitis of the knee can occur when the bursa fills with blood from injury and overuse, such as from athletic competition. Bursitis can also occur from rheumatoid arthritis and from deposits of crystals, as seen in patients with gouty arthritis and pseudogout. The prepatellar bursa can also become infected with bacteria (septic bursitis). When this happens, fever may be present. This type of infection usually occurs from breaks in the overlying skin or puncture wounds. The bacteria involved in septic bursitis of the knee are usually those that normally cover the skin, called Staphylococcus. Rarely, a chronically inflamed bursa can become infected by bacteria spreading through the blood.
What are knee bursitis symptoms and signs?
Bursitis can lead to varying degrees of swelling, warmth, tenderness, and redness in the overlying area of the knee. As compared with knee joint inflammation (arthritis), it is usually only mildly painful. It is frequently associated with increased pain when kneeling and can cause stiffness and pain with walking. Also, in contrast to problems within the knee joint, the range of motion of the knee is frequently preserved.
How is knee bursitis diagnosed?
Bursitis of the knee is diagnosed based upon the typical location of a bursa displaying signs of inflammation including pain, tenderness, stiffness, and sometimes redness and warmth. Typically, there is point tenderness at the site of the inflamed bursa.
How is prepatellar bursitis of the knee treated?
The treatment of any bursitis depends on whether or not it involves infection. Aseptic prepatellar bursitis can be treated with ice compresses, rest, and anti-inflammatory and pain medications. Occasionally, it requires aspiration of the bursa fluid. This procedure involves removal of the fluid with a needle and syringe under sterile conditions and can be performed in the doctor’s office. Sometimes the fluid is sent to the laboratory for further analysis.
Noninfectious knee bursitis can also be treated with an injection of cortisone medication into the swollen bursa. This is sometimes done at the same time as the aspiration procedure.
Septic bursitis requires even further evaluation and treatment. The bursal fluid can be examined in the laboratory to identify the microbes causing the infection. It requires antibiotic therapy, often intravenously. Repeated aspiration of the inflamed fluid may be required. Surgical drainage and removal of the infected bursa sac (bursectomy) may also be necessary.
After the initial period of rest, the goal of physical therapy is to regain any loss of ROM, while increasing the flexibility of the quadriceps and hamstrings. Use of therapeutic modalities can be helpful to assist stretching in this period.
Physical Therapy Interventions
Common Physical Therapy interventions in the treatment of Knee Bursitis include:
Manual Therapeutic Technique (MTT): hands on care including soft tissue massage, stretching and joint mobilization by a physical therapist to regain mobility and range of motion of the knee. Use of mobilization techniques also help to modulate pain.
Therapeutic Exercises (TE) including stretching and strengthening exercises to regain range of motion and strengthen muscles of the knee to support, stabilize, and decrease the stresses place on the bursa and tendons of the knee joint.
Neuromuscular Reeducation (NMR) to restore stability, retrain the lower extremity and improve movement techniques and mechanics (for example, running, kneeling, squatting and jumping) of the involved lower extremity to reduce stress on bursa and tendons in daily activities.
Modalities including the use of ultrasound, electrical stimulation, ice, cold laser and others to decrease pain and inflammation of the involved bursa.
Home program including strengthening, stretching and stabilization exercises and instructions to help the person perform daily tasks and advance to the next functional level.
Kneecap Bursitis Exercises
You can stretch your leg right away by doing the first 3 stretching exercises. Do the other exercises to strengthen your leg.
Hamstring stretch on wall:
Lie on your back with your buttocks close to a doorway. Stretch your uninjured leg straight out in front of you on the floor through the doorway. Raise your injured leg and rest it against the wall next to the door frame. Keep your leg as straight as possible. You should feel a stretch in the back of your thigh. Hold this position for 15 to 30 seconds. Repeat 3 times.
Standing calf stretch:
Stand facing a wall with your hands on the wall at about eye level. Keep your injured leg back with your heel on the floor. Keep the other leg forward with the knee bent. Turn your back foot slightly inward (as if you were pigeon-toed). Slowly lean into the wall until you feel a stretch in the back of your calf. Hold the stretch for 15 to 30 seconds. Return to the starting position. Repeat 3 times. Do this exercise several times each day.
Stand an arm’s length away from the wall with your injured side farthest from the wall. Facing straight ahead, brace yourself by keeping one hand against the wall. With your other hand, grasp the ankle on your injured side and pull your heel toward your buttocks. Don’t arch or twist your back. Keep your knees together. Hold this stretch for 15 to 30 seconds.
Sit on the floor with your injured leg straight and your other leg bent. Press the back of the knee of your injured leg against the floor by tightening the muscles on the top of your thigh. Hold this position 10 seconds. Relax. Do 2 sets of 15.
Sit on a firm surface with your legs straight in front of you. Slowly slide the heel of the foot on your injured side toward your buttock by pulling your knee toward your chest as you slide the heel. Return to the starting position. Do 2 sets of 15.
Straight leg raise:
Lie on your back with your legs straight out in front of you. Bend the knee on your uninjured side and place the foot flat on the floor. Tighten the thigh muscle on your injured side and lift your leg about 8 inches off the floor. Keep your leg straight and your thigh muscle tight. Slowly lower your leg back down to the floor. Do 2 sets of 15.
Side-lying leg lift:
Lie on your uninjured side. Tighten the front thigh muscles on your injured leg and lift that leg 8 to 10 inches away from the other leg. Keep the leg straight and lower it slowly. Do 2 sets of 15.
Wall squat with a ball:
Stand with your back, shoulders, and head against a wall. Look straight ahead. Keep your shoulders relaxed and your feet 3 feet from the wall and shoulder’s width apart. Place a soccer or basketball-sized ball behind your back. Keeping your back against the wall, slowly squat down to a 45-degree angle. Your thighs will not yet be parallel to the floor. Hold this position for 10 seconds and then slowly slide back up the wall. Repeat 10 times. Build up to 2 sets of 15.
The role of the occupational therapist in this scenario is to address modifications of activities in patients diagnosed with prepatellar bursitis secondary to overuse. Emphasize patient education, avoidance of kneeling, and use of kneepads if kneeling is necessary.
What about the other knee bursae?
A second bursa of the knee is located just under the kneecap beneath the large tendon that attaches the muscles in front of the thigh and the kneecap to the prominent bone in front of the lower leg. This bursa is called the infrapatellar bursa, and when inflamed, the condition is called infrapatellar bursitis. It is commonly seen with inflammation of the adjacent tendon as a result of a jumping injury, hence the name “jumper’s knee.” This condition is generally treated with ice, rest, and oral anti-inflammatory and/or pain medicines.
A third bursa of the knee is called the “anserine bursa.” It is located on the lower inner side of the knee. This bursa most commonly becomes inflamed in middle-aged women. This condition is referred to as anserine bursitis. Anserine bursitis is particularly common in those who are obese. These patients can notice pain in the inner knee while climbing or descending stairs. Anserine bursitis is generally treated with ice, rest, and oral anti-inflammatory and/or pain medicines, although cortisone injections are also given.
What is the prognosis (outlook) of knee bursitis?
The outlook for knee bursitis is generally very good. Mild bursitis resolves spontaneously with rest. More significant bursitis can require medications (either taken by mouth or locally injected) to reduce inflammation. Infectious bursitis requires drainage, possibly surgical resection, and antibiotics.
Can knee bursitis be prevented?
To the extent that the bursitis is caused by injury or athletic activity, it can be prevented by avoiding reinjury to the bursa and adjacent tissues.