 |
... |
|
easier reduction of joint bleeds.
 "Two days after the procedure the patient can resume normal daily functions," says Dr. J. Joist. |
For some PWHs, this is an uncommon or even rare problem that can be controlled with factor therapy and does not lead to serious joint damage. But for others, joint bleeds are a frequent, ongoing problem, leading to long-term disability, deformity, pain and a reduced quality of life.
A frequently bleeding joint, called a target joint, is often defined as one that bleeds more than four times within six months. Until recently, the only options for reducing the number and severity of such joint bleeds were preventative daily factor infusion (prophylactic therapy) or surgery to remove the inflamed, thickened synovial tissue that lines the inside of joints. This procedure, called synovectomy, has traditionally been performed by opening the joint via a surgical incision or by using an arthroscope. But now an alternative method is gaining considerable favour.
Called radionuclide synovectomy, this innovative procedure involved the injection of a radioactive substance, such as phosphorus-32 chronic phosphate (the substance Yttrium-90 is used in similar procedures in South Africa). Because it is performed on an outpatient basis, it does not require the hospital stay and lengthy rehabilitation period that surgery does. It also has fewer of the risks associated with surgery. Pioneered in Canada, this type of synovectomy has been performed in the U.S.A. in only about 150 patients since 1986. However, radionuclide synovectomy using other radioactive substances has been evaluated in patients with other forms of arthritis such as rheumatoid arthritis as long ago as the 1950s. The current procedure does have some risks associated with it, but early results show great promise.
HOW JOINT BLEEDS
AFFECT JOINTS
Each episode of joint bleeding causes inflammation and swelling of the synovial membrane. If bleeding occurs often or is not treated adequately, the inflammation may become chronic and is called chronic synovitis. Then the inflammation leads to enlargement or thickening of the synovial membrane and the release of substances which, over time, can destroy cartilage and even bone. The possible long-term result: disabling joint deformity and loss of joint mobility and function. And once cartilage has been destroyed and there is a wearing away, or erosion, of the bone, the only option to restore mobility is joint replacement therapy -- a complicated procedure requiring a long rehabilitation process.
TRADITIONAL ALTERNATIVES
Beginning in 1969, a surgical approach was applied to the treatment of synovitis. This procedure, synovectomy, involved removal of the inflamed synovial membrane, allowing a new, normal membrane to form. Care is taken to preserve any undamaged cartilage. Synovectomy can be performed through an open incision (open synovectomy) or an arthroscope/tube (arthroscopic synovectomy). Although open synovectomy is effective in reducing the number and severity of bleeding episodes, it can cause a loss of motion. The surgical procedure also requires a major hospital stay and lengthy rehabilitation period. Factor therapy is required pre- and postoperatively as well as during the recovery period, until healing and adequate joint motion have been achieved.
Arthroscopic synovectomy requires a shorter rehabilitation period, and, in some cases, maintains or even improves range of motion. It is still considered major surgery, however, requiring a hospital stay and prophylactic factor for at least a two to three-week recovery period.
THE NEWEST APPROACH:
RADIONUCLIDE SYNOVECTOMY
Removal of the inflamed synovial membrane can relieve pain and possibly provide some protection against the progress of joint disease. But in time, the membrane grows back and may become inflamed again. Does temporary relief justify the risks and expense of a major surgical procedure? That concern has led to the development of a nonsurgical approach to synovectomy -- radionuclide synovectomy. Rather than actually removing the damaged synovial membrane, this technique destroys the membrane through radiation.
The main advantage of this new procedure: "One to two days after the procedure the patient can resume normal daily functions!" says J. Heinrich Joist, MD, PhD, professor of Internal Medicine and Pathology and Director of the Haemostasis and Thrombosis Unit and Adult Haemophilia Centre at the St. Louis University School of Medicine.
At this centre, where some of the first successful radionuclide synovectomies were performed beginning 1986, potential candidates for the procedure are those who experience four or more bleeds in the same joint within six months. But before the procedure is considered for these patients, Dr. Joist recommends trial of an alternative measure -- four to six weeks of prophylactic factor therapy. "About 50 to 60 percent of patients do well after this period of prophylaxis," he emphasises. They are able to stop therapy without a return to frequent bleeding. For the others, options are continued prophylaxis, perhaps indefinitely, or radionuclide synovectomy.
HOW THE PROCEDURE WORKS
At the St. Louis University Health sciences Centre, a team composed of a nuclear medicine physician and an orthopaedic surgeon perform the procedure in the nuclear medicine department of the hospital.
The radioactive substance phosphorus-32 chronic phosphate is injected into the joint (Yttrium-90 in South Africa) at a time when the patient has not been bleeding, and preferably after a period of prophylactic therapy so that the swelling of the membrane is already reduced as much as possible. Right before the injection, the patient is given appropriate factor therapy because, although this is not considered surgery, it is an invasive procedure. After the injection the treated joint is splinted for one to two days. Even so, a patient can usually return to work or school the day after the procedure.
The clinical results of radionuclide synovectomy seem to be about the same as those of surgical synovectomy in terms of reducing the frequency of bleeds. There may be a greater improvement in range of motion, but since no more than 150 procedures have been performed in the few centres currently undertaking this technique in the United States, it is too early to tell for certain. As with surgical synovectomy, there is no guarantee that this procedure will prevent further joint damage.
What is certain is that radionuclide synovectomy costs less than surgical synovectomy; hospital and rehabilitation costs are lower and so are socio-economic costs since the person's life is not disrupted by a major surgical procedure. The radionuclide technique is also a good deal less expensive than long-term prophylactic therapy. Dr. Joist has calculated that the average savings in factor alone is about $54,000 (+-R250,000) per patient per year.
WHAT ABOUT THE RISKS
OF RADIATION
The greatest concern haematologists and other members of the haemophilia treatment team have is the risk of radiation toxicity or long-term effects of radiation therapy. Dr. Joist explains that there is always some risk associated with radiation therapy, especially if the procedure is not done correctly. But the P-32 colloid is used for this procedure specifically because it has little potential to leak out of the joint into other areas of the body. Also, radioactive synovectomy with P-32 colloid and other radionuclides has been performed for 30 years in various countries without evidence of an increased risk of cancer. Although P-32 is not yet approved by the FDA for use specifically in haemophillic synovitis, it is approved for rheumatoid arthritis, and most insurance carriers have agreed to pay for this procedure.
THE RIGHT CANDIDATES
Because there is still a low level of risk involved with this procedure the decision to have it done should be made only after careful consultation with the haemophilia treatment team. But, as Dr. Joist points out, "For patients who don't want or cannot afford continued prophylaxis, extended perhaps indefinitely, this outpatient procedure can provide relief from frequent joint bleeding without the prolonged rehabilitation period and expense of surgery."
For more information about radionuclide synovectomy, contact your local Haemophilia Treatment Centre
Susan Roher is a healthcare writer in Chappaqua, New York.
