Synovial chondromatosis

Synovial chondromatosis is a disease affecting the synovium, a thin flexible membrane around a joint.

Symptoms

Patients usually complain of pain in one joint, which persists or months, or even years, does not ease with exercise, steroid injection or heat treatment, shows nothing on X-ray, but shows a definite restriction of movement.

There are 3 defined stages to this disease:

early: no loose bodies but active synovial disease; 
transitional: active synovial disease, and loose bodies; 
late: loose bodies but no synovial disease;

In the early stages of the disease it is often confused with tendinitis and/or arthritis. Once it reaches transitional the loose bodies become apparent with X-ray in greater than 70% of cases, with MRI often showing where xray fails.

In the disease, the thin flexible membrane of the synovium gradually forms blisters which calcify and enlarge. These nodules eventually break free and float around the joint space becoming larger – these add to the discomfort and stiffness of the joint.

The disease is rare and little known and currently no know cure. The affected tissue will show up as a semi-solid mass in an NMR scan, final diagnosis is usually confirmed by taking a biopsy.

People suffering from this disease are nearly always (but not exclusively) male, and usually in their forties. The disease generally affects only one of the larger weight bearing joints (hip, ankle, knee) – although the elbow, and wrist can also be affected.

For the first time a website has been set up for sufferers and their families to discuss their condition as there is currently little known about the condition and its treatment options. http://www.synovial-chondromatosis.com

Treatment

Treatment is frequently by means of removal of the loose bodies and of a partial or full Synovectomy (removal of the synovium)

Full synovectomy is a moderately major operation and involves completely exposing the joint and removing the affected tissue. Partial synovectomy is normally done arthroscopically. Synovectomies are normally carried out by shaving the lining of the knee but there are other ways of achieveing this by either freezing the synovium or by the use of radiation treatment.

The need for further procedures is greater than 25% although normally the frequency of the required removal of loose bodies is reduced by the previous synovectomy. There have been documented cases of malignant transformation however this is rare.

Whilst the condition can be described as a ‘benign growth’ it seldom affects more than one joint, and does not usually affect surrounding tissue.