Name = Baker's cyst
ICD10 = ICD10|M|71|2|m|70
ICD9 = ICD9|727.51
MedlinePlus = 001222
eMedicineSubj = radio
eMedicineTopic = 72
DiseasesDB = 1224
A Baker's cyst, otherwise known as a
popliteal cyst, is a benign swelling found behind the knee joint. It is named after the surgeon who first described it, Dr. William Morrant Baker(1838-1896). [cite web | title=William Morrant Baker | url=http://www.whonamedit.com/doctor.cfm/649.html | publisher= Who Named It]
In adults, Baker's cysts usually arise from almost any form of knee
arthritisand cartilage(particularly the meniscus) tear. Baker's cysts can be associated with Lyme disease. Baker's cysts in children do not point to underlying joint disease. Baker's cysts arise between the tendons of the medial head of the gastrocnemius and the semimembranosus muscles. They are posterior to the medial femoral condyle.
The synovial sack of the knee joint can, under certain circumstances, produce a posterior bulge, into the popliteal space, the space behind the knee. When this bulge becomes large enough, it becomes palpable and cystic. Most Baker's cysts maintain this direct communication with the synovial cavity of the knee, but sometimes, the new cyst pinches off. A Baker's cyst can rupture and produce acute pain behind the knee and in the calf and swelling of the calf muscles.
Diagnosis is by examination. They are easier to see from behind with the patient standing with knees fully extended and then most easily felt with the knee partially flexed. Diagnosis is confirmed by ultrasonography, although if needed and there is no suspicion of a
popliteal artery aneurysmthen aspiration of synovial fluid from the cyst may be undertaken with care. An MRI image can reveal presence of a Baker's cyst.
A burst cyst can cause calf pain, swelling and redness that may mimic
thrombophlebitisor a potentially life-threatening deep vein thrombosis(DVT) which may need to be excluded by urgent blood tests and ultrasonography. Although an infrequent occurrence, a Baker's cyst can compress vascular structures and cause leg edema and a true DVT.
Baker's cysts usually require no treatment unless they are symptomatic. Often rest and leg elevation are all that is needed. If necessary, the cyst can be aspirated to reduce its size, then injected with a
corticosteroidto reduce inflammation. Surgical excision is reserved for cysts that cause a great amount of discomfort to the patient. A ruptured cyst is treated with rest, leg elevation, and injection of a corticosteroid into the knee. Recently, prolotherapy(in use at the Mayo Clinicsince 2005) has shown encouraging results as an effective way to treat Baker's cysts and other types of musculoskeletal conditions.cite journal |author= |title=Alternative treatments. Dealing with chronic pain |journal=Mayo Clinic health letter (English ed.) |volume=23 |issue=4 |pages=1–3 |year=2005 |pmid=15864836 |doi=] cite book |author=March Darrow |title=Prolotherapy: Living Pain Free |publisher=Protex Press |location= |year= |pages= |isbn=0971450323 |oclc= |doi=]
Baker's cysts in children, unlike in older people, nearly always disappear with time, and rarely require excision.
Ice pack therapyis believed to be an effective way of controlling the pain caused by Baker's cyst.Fact|date=February 2007 Ice must not be applied directly onto the skin but be separated by a thin cloth. Alternatively, cooling packs may be used, but the total application time for any product is for no more than 15 minutes at a time.
Medications bought at
pharmaciesmay be used to help soothe pain. Painkillers with paracetamol, a.k.a. tylenol(acetaminophen), or with the additional anti-inflammatoryaction (such as ibuprofenor naproxen), may be used. Stronger non-steroidal anti-inflammatory drugs may be required by prescription from one's general practitioner.
Heat is also a recognised treatment.Fact|date=February 2007 The application of a
heating padon a low setting for 10-20 minutes may relieve some pain, but only if instructions are followed carefully.
knee bracecan offer support, but relieve pain by stimulating nerve fibre,Fact|date=February 2007 giving the feel of stability in the joint. If only support is necessary, a simple elastic bandage is recommended; however, braces compress the back of the knee, where it is most tender, and can cause pain.
Rest and specific exercise
Many activities can put strain on the knee, and cause pain in the case of Baker's cyst. Avoiding activities such as squatting, kneeling, heavy lifting, climbing, and even running can help prevent pain. Despite this, some exercises can help relieve pain, and a
physiotherapistmay instruct on stretching and strengthening the quadricepsand/or the patellar ligament.
* [http://www.jointhealing.com/pages/knee/bakers_cyst.html Joint Healing.com-Baker's Cyst]
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Look at other dictionaries:
Baker's cyst — Ba·ker s cyst bā kərz n a swelling behind the knee that is composed of a membrane lined sac filled with synovial fluid and is associated with certain joint disorders (as arthritis) Baker William Morrant (1839 1896) British physician. Baker spent… … Medical dictionary
Baker's cyst — a cyst behind the knee resulting from rupture or herniation of the synovial membrane from a knee joint affected by osteoarthritis. [W. M. Baker (1839–96), British surgeon] … The new mediacal dictionary
Киста Бейкера (Baker'S Cyst) — киста, развивающаяся на задней поверхности коленного сустава. Образуется либо из синовиальной сумки, либо в результате выбухания синовиальной мембраны вследствие слабости капсулы коленного сустава. Источник: Медицинский словарь … Медицинские термины
Cyst — This article is about cysts in the body. For the ICAO airport code CYST, see St. Theresa Point Airport. For hard shelled resting stages of some small organisms, see Microbial cyst. Cyst Classification and external resources … Wikipedia
Cyst, synovial, of the popliteal space — A swelling in the space behind the knee (the popliteal space). The swelling is composed of a membrane lined sac filled with synovial fluid that has escaped from the joint. Commonly called Bakers cyst … Medical dictionary
Baker cyst — A swelling in the space behind the knee (the popliteal space) composed of a membrane lined sac filled with synovial fluid that has escaped from the joint. Named after the British surgeon William Morrant Baker (1839 1896). Also called a synovial… … Medical dictionary
Cyst — A closed sac or capsule, usually filled with fluid or semisolid material. * * * 1. A bladder. 2. An abnormal sac containing gas, fluid, or a semisolid material, with a membranous lining. SEE ALSO: pseudocyst. [G. kystis, bladder] adventitious c.… … Medical dictionary
Cyst, Baker — A swelling in the space behind the knee (the popliteal space) composed of a membrane lined sac filled with synovial fluid that has escaped from the joint. Named after the British surgeon William Morrant Baker (1839 1896). Also called a synovial… … Medical dictionary
Baker — William M., English surgeon, 1839–1896. See B. cyst. James Porter, U.S. physician, *1902. See Charcot Weiss B. syndrome. John Randal, English zoologist, *1900. See B. pyridine extraction, B. acid hematein … Medical dictionary
William Morrant Baker — ( born October 20, 1839, Andover, Hampshire, England died October 3, 1896, Pulborough, Sussex) was an English physician and surgeon. He first described the condition now known as Baker s cyst.LifeWilliam Morrant Baker was the son of a solicitor… … Wikipedia