Robert J. Snyder, MD
As a bone and joint specialist, I get to see patients everyday with a variety of interesting and unique conditions that keeps my job from ever getting boring. Sometimes the cells or tissues of the body grow abnormally and cause problems – we often call this cancer. However, other times this unusual growth is benign, but it can still be highly problematic for the patient. That’s the case with Synovial Chondromatosis and, if left untreated, it can be highly destructive.
So, let’s break down this scary sounding term. Synovial Chondromatosis – synovial meaning the tissue that lines the joint and produces lubricating fluid for it, and chrondromatosis – chondro- meaning cartilage; oma – meaning tumor; osis – meaning an increase. To put it simply, the synovium, instead of only producing synovial fluid, starts producing nodules of cartilage. These nodules can vary in size from pinheads to marble-sized spheres. When these nodules break loose and begin to float free in the joint capsule, they rub on the cartilage in the joint, causing it to break down. This eventually leads to arthritis pain and dysfunction. The synovial fluid will continue to feed these nodules, and they can grow large, harden, or turn into bone. They can multiply and take up the entire joint capsule or even push outside into the surrounding tissue. At this point, the patient will have severe and debilitating pain.
Synovial Chondromatosis is a relatively uncommon disorder. It typically happens to people in their fifties and is rarely seen in people under twenty. It is most often seen in the knee joint but can happen in any joint of the body. Men are affected much more often than women. We don’t know what causes this disorder and there doesn’t seem to be any genetic component to its origin.
Symptoms of synovial chondromatosis are like that of osteoarthritis, with joint pain, swelling, excess fluid in the joint, decreased range of motion and tenderness. Crepitus (the crackles you hear with joint movement) may be apparent and sometimes the nodules may be felt during palpation in certain joints.
Diagnosis involves ordering x-rays of the affected joint, and a physical examination and careful questioning of the patient. If the nodules in the joint are large enough or have calcified or ossified, they will be observable on x-ray. If not, conservative treatment will start with NSAIDs, Physical Therapy, a steroid injection in the joint, activity modification. If the condition continues to worsen, an MR scan will be ordered of the joint. Any nodules present in the joint will be able to be visualized clearly.
Once a diagnosis has been confirmed, treatment almost always involves surgery to remove the floating pieces of cartilage and the synovium of the joint. The surgery will either be done arthroscopically (through small incisions using a camera) or as an open procedure depending upon the size and number of the loose nodules and the condition of the synovium.
Recovery will also depend upon whether the surgery was open or arthroscopic and on what joint it was performed. Patients should be aware that this condition can recur in about 20 percent of those who have surgery, as the synovium does regrow in the joint after a period of time. Regular follow-up visits with me will be important to monitor the joint for signs of recurrence or for signs of the development of osteoarthritis.