Why are treatments like Synvisc needed?
Arthritis is one of the most common medical conditions in this country. The total social cost of this condition has been estimated to be as high as 1% of the gross national product in the United States (2). The knee is among the most commonly involved joints, and can be one of the most serious affecting many aspects of an individual’s quality of life. Patients with osteoarthritis of the knee are susceptible to complications from other medical conditions, as they are more likely to live a sedentary lifestyle and are more often obese. Effective treatment for this disorder is a priority of orthopedic surgeons.What is Synvisc?
Synvisc is a substance that is secreted by cells in the cartilage of joints. It is one of the major molecular components of joint fluid, and it gives the joint fluid, also called synovial fluid, its viscous quality. The high viscosity of synovial fluid allows for the cartilage surfaces of joints to glide upon each other in a smooth fashion. This is what gives the joint fluid its comparison to motor oil, or joint lubrication.
Numerous studies have been performed in the past decade to assess the effectiveness of Synvisc as a treatment for osteoarthritis. However, no clear understanding of how well these injections perform has emerged. Early studies were performed on too few patients and the follow-up period was limited to a short time. Some studies showed a benefit, primarily in reduction of pain as assessed by patients, when compared to patients getting a placebo-a saline injection (2,3). But to contradict these studies, other trials showed no benefit to the Synvisc injections (4,5).
Should I use Synvisc?
So where does this leave patients? Essentially, the jury is still out. No study has shown that this is an effective treatment in a large number of patients over a long period of time. Osteoarthritis, like other chronic conditions, has a course that naturally waxes and wanes. Because of this, it is impossible to definitively determine from a short study whether or not a treatment is having a reproducible effect, or if the benefit shown is part of the natural variation in disease severity.That said, Synvisc has been shown to be of benefit in some patients. Most promising, a recent report announced by the American Academy of Orthopaedic Surgeons, states that this treatment offers a delay in surgical treatment in patients needing total knee replacement (6). This study found that almost 75% of patients were able to delay knee replacement surgery after using Synvisc treatments. Furthermore, no study to date has found serious adverse side effects associated with the use of Synvisc injections in the knee joint. While there have been concerns about potential allergic reactions, this has not been demonstrated. Therefore, treatment has been shown to be safe, and there is potential that patients can benefit from these treatments.
Synvisc References
- (1) Rashad S, et al., Effect of non-steroidal anti-inflammatory drugs on the course of osteoarthritis. Lancet 2:519-521. 1989.
- (2) Lohmander, L, et al., Intra-articular hyaluronan injections in the treatment of osteoarthritis of the knee: a randomized, double blind, placebo controlled multicentre trial. Annals of Rheumatic Diseases. 55:424-431. 1996.
- (3) Dixon, A, et al., Clinical trial of intra-articular injection of sodium hyaluronate in patients with osteoarthritis of the knee. 11:205-213. 1988.
- (4) Henderson, E,, et al., Intra-articular injections of 750kD hyaluronan in the treatment of osteoarthritis: a randomized single centre double-blind placebo-controlled trial of 91 patients demonstrating lack of efficacy. Annals of Rheumatic Diseases. 53:529-534. 1994.
- (5) Dhalberg, L, et al., Intraarticular injections of hyalurnan in patients with cartilage abnormalities and knee pain. Arthritis & Rheumatism. 37:521-528. 1994.
- (6) http://www.pslgroup.com/dg/e19f2.htm
