A randomized, double-blind clinical trial by researchers at Hospital for Special Surgery has revealed that corticosteroids are more effective than the more expensive treatment, hylan G-F 20 (Synvisc One, Genzyme Biosurgery), in providing pain relief to patients with thumb arthritis. The study also showed that both of these commonly used treatments provided clinically meaningful pain relief, but so did a placebo injection.
"On average, each of the therapies resulted in clinically meaningful improvement in pain," said Lisa Mandl, M.D., MPH, a rheumatologist at Hospital for Special Surgery, in New York City, who led the study. "What this study suggests is that a number of different injectable treatments might be effective for patients who have pain in their thumb and that the one that appeared to be the most effective was corticosteroids." The study will be reported at the annual meeting of the American College of Rheumatology/Association of Rheumatology Health Professionals, to be held Nov. 9-14, in Washington D.C.
The new study is the first large randomized clinical trial in patients with carpometacarpal (CMC) osteoarthritis (thumb arthritis). The study compared a placebo, an injection of a local anesthetic called bupivacaine, with two commonly used injectable treatments: a corticosteroid called triamcinolone acentoide and hylan G-F 20, which is made from a natural substance that lubricates and decreases inflammation in the joints. CMC osteoarthritis, caused by regular wear and tear, is common in individuals over 60. It occurs in 80% of women who are 80 years of age or older.
The researchers enrolled 200 patients with thumb arthritis and randomized them to receive bupivacaine, hylan G-F 20, or triamcinolone. The average age of patients in the study was 66.5 and roughly 70% were female. Over the 26-week study, pain, as measured by the Visual Analogue Scale (VAS), showed a statistically and clinically significant improvement in all treatment groups. Each group gained slightly more than an average of 10 points; an improvement in 10 points is clinically meaningful. Patients who received corticosteroids had slightly greater improvements in pain compared to patients who received Hylan G-F 20. No treatment arm had clinically meaningful improvements in function.
"Overall, this was a negative trial," said Dr. Mandl. "If you compare the three treatments to each other, neither the steroid or Synvisc provided better pain relief than bupivacaine. Bupivacaine shouldn't do anything. It should numb and wear out in 20 minutes, but even that seems to help some people. What this suggests is that maybe the injection itself is making people feel better."
The researchers say that clinicians can consider trying any of the three treatments in their patients with CMC. "It may be that steroids are the most effective, so I would probably try steroids first. If that didn't work, then I would try hylan G-F 20. If patients were hesitant to try either steroids or hylan G-F 20, I'd even try bupivacaine," said Dr. Mandl.
The researchers point out that clinicians need to weigh the pros and cons of the different treatments. For example, Hylan G-F 20 is usually prescribed every six months and could be used repeatedly over time. Steroid injections, however, if given repeatedly, could end up damaging the joint further. Hylan G-F 20 costs in the ballpark of $600 for each treatment, whereas corticosteroids cost roughly $15 per treatment.
Dr. Mandl points out that even patients with very severe osteoarthritis benefited from the treatments. Arthritis severity is measured by the amount of cartilage left in a joint; in Grade 4, there is no cartilage left and bone is grinding against bone. "Even if you have a patient with terrible arthritis, it is worth trying one of these therapies," said Dr. Mandl. "There is no other therapy besides surgery for these people once they have failed other conservative measures."