Bursitis of the knee
Overview
Bursae are small closed sacks made of connective tissue. They have a synovial membrane and are filled with synovial fluid. The function of a bursa is to reduce friction and cushion between a tendon and the hard tissues of the body, for example bone.
Bursitis is inflammation of the bursa. When they are inflamed, they produce excessive fluid, which in turn causes pain and restricted movement.
There are a number of common bursa problems which have been attributed names;
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Housemaid’s knee – prepatellar bursa
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Student’s elbow – point of the olecranon
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Weaver’s bottom – ischial tuberosity
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Subacromial bursitis – between the acromion and humerus
symptoms
The symptoms of bursitis vary according to which bursa is affected. However, the general symptoms are as follows;
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Warmth
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Tenderness
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Swollen defined area
More specifically, localised swelling in front of the patella suggests prepatellar bursitis, AKA “Housemaids Knee”. This bursa is at the front of the knee joint, it is superficial and between the skin and the patella.
Whereas localised swelling below the patella, in front of the patellar tendon, suggests a superficial infrapatellar bursitis, AKA “Clergyman’s Knee”. This bursa is found just below the kneecap and it sits around the patella tendon.
Smaller swellings either side of the tendon suggests deep infrapatellar bursitis or a large infrapatellar fat pad.
A subtle swelling below the medial joint line could be an anserine bursitis.
The normal cause of bursitis is repetitive stress, performing the same movement many times, causing irritation, thus the bursa fills with a greater volume of fluid resulting in pain. However, in some cases a sharp blow to the area can trigger bursitis. People who kneel a lot often suffer from bursitis, hence “Priest Knee, Housemaids Knee”.
Sometimes bursitis can be caused by a bacterial infection, in this case medical assessment is required.
Other causes include;
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Osteoarthritis
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Rheumatoid arthritis
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Gout.
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Syphilis
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Tuberculosis
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Obesity in the case of pes anserine bursitis.
Causes
EXAMINATION
Pain is provoked by compression, direct pressure over a localised swelling causes pain then it is likely to be a bursa problem.
Sometimes imaging (X ray, MRI scan, Ultrasound) is required to rule out other conditions, for example OA.
If an infection or gout is suspected, then a needle sample is taken to be analysed. Often draining the bursa is performed at the same time.
treatment
The basic treatment methods are ice and ultrasound.
If the cause of the bursitis is an infection, then the relevant medication is prescribed.
The patient should avoid kneeling on the affected area and should consider using kneepads.
Avoid excessive squatting.
Massage treatment of bursitis should be considered a direct contraindication, in the acute phase.
In a subacute phase massage therapy may be able to release some of the muscle tension over and around the affected area.
Carefully prescribed stretching and strengthen exercises should be encouraged in the subacute phase.
Corticosteroid injection can be used in persistent cases.
Aspiration in the short term to reduce pain.
Surgery in severe chronic cases.
In rare cases bursitis can be caused by a pathogen and thus massage is contraindicated to prevent spreading the pathogen.