Ask the Doctors: 10/05
I’ve read that hyaluronic acid knee injections can be used to postpone knee surgery. Can hyaluronic acid in pill form provide the same relief?
Hyraluronic acid (HA) is an important component of the synovial fluid that acts as a cushion and lubricant for joints. It also is a major component of extracellular matrix of the cartilage, helping to enhance the ability of cartilage to resist shear and maintain a resiliency to compression. Because synovial fluid from osteoarthritic joints has a lower elasticity and viscosity than the synovial fluid from normal joints, it seems reasonable that increasing the amount of HA in the synovial fluid would alleviate pain and improve function. However, HA itself is not absorbed when taken orally and its use is therefore limited to an injectable form.
There is no explanation as to why some individuals react positively to this therapy and others do not. Scientific studies have reported some pain relief, which lasts from nine to 12 months in 50-80 percent of patients who have had a series of HA injections. The long-term effects of injected HA, including alteration of the natural history of osteoarthritis, have not yet been clearly identified.
In reading your article on osteoporosis in the July 2005 issue, I noticed your list of medications did not include any reference to a new one—lasofoxifene, a selective estrogen receptor modulator (SERM). Forteo seems very expensive, and too much of a risk for bone cancer.
Lasofoxifene is still in trials and is not yet available. Studies have shown that it lowers lipids, increases bone mass, and may improve vaginal dryness. The other SERM is raloxifene (Evista), which has undergone a large trial supporting its efficacy in reducing vertebral fractures.
Forteo (teriparatide) includes a black box warning which states that it has caused osteosarcoma (bone cancer) in rats. Most clinicians do not feel this is a high risk and should not affect prescribing, except in situations where the risk of osteosarcoma is high—Paget’s disease, previous radiation to the skeleton, children and young adults with open epiphyses (the growth end of long bones). The drug is marketed in Europe as Forsteo. The European Medicines Agency, the European equivalent of the U.S. Food and Drug Administration (FDA), does not feel that the risks warrant a black-box warning.
I’ve heard about a procedure commonly performed in Europe of injecting Traumeel into joints to stimulate cartilage growth. What can tell me about the procedure, and when will it be permitted in the United States?
Traumeel is a homeopathic mixture of highly diluted extracts from medicinal plants and minerals. It is available in creams, drinkable form, and injectable solutions and has been advertised for the treatment of a variety of conditions, including arthritis, muscle aches and bruises, burns, gingival disease, rhinitis, dislocations, and fractures.
Although European homeopathic literature cites success with its use, no scientific studies have established the effectiveness of Traumeel in treating any of these conditions. Since many homeopathic remedies contain no detectable amount of any active ingredient, it is impossible to know whether they contain what their label says. Until Traumeel is scientifically established to be of benefit and its preparation is rigidly controlled and monitored, FDA approval and its use by U.S. physicians are unlikely. Currently, no injected medications have proven effective in promoting cartilage growth, and the claims made for this “natural remedy” appear to be unfounded.