Broken Leg? Pass the Cortisone!
May 30, 2001 -- Steroid drugs like dexamethasone, which are similar to cortisone, are a common treatment for a host of conditions, including inflammation due to allergies. New research now shows this drug may actually have a role in treating various bone diseases -- from broken bones to bone diseased by cancer.
Research reported in the May issue of Journal of Bone and Mineral Research shows dexamethasone appears to help bone-producing cells maintain their ability to form new bone after they have been transplanted from one location to another.
Co-author of the new Japanese study, Kazuhito Satomura, DDS, PhD, says that the steroid dexamethasone is somehow able to help immature, human bone-producing cells, called osteoblasts, maintain their bone-producing function after they have been transplanted from humans into mice. Satomura is an assistant professor specializing in surgery in the School of Dentistry at the University of Tokushima in Japan.
According to bone expert Joseph A. Buckwalter, MD, lots of people require substances or procedures to help with bone regrowth.
"In orthopaedics," he tells WebMD, "we have traumatic bone defects, where people lose a section of bone due to injury. We have bone defects due to [cancerous] tumors that destroy bone. We have loss of bone due to infection. We have children with [birth defects] of the skeletal system. We have bone cysts that destroy bone. That's just the top [few] indications for things that form bone." Buckwalter is professor and chairman of the department of orthopaedic surgery at the University of Iowa in Iowa City and a member of the American Academy of Orthopaedic Surgeons.
Traditionally, doctors have relied on bone grafts to treat these patients. Bone grafting involves taking the patient's own bone from one part of the body and transplanting it for use in another part, explains Buckwalter.
"We've also used bone transplanted from one person to another, called allografts, and that's why there are all these big bone banks around the world," Buckwalter says. "But the new biotechnology is bone stimulants or bone substitutes that come off the shelf in a package. ... Those are really simple [to use]. You take it off the shelf, unscrew the cap, and pour it into the hole."
Buckwalter finds this new research promising. "It really looks as though the dexamethasone treatment greatly improved the ability of the osteoblast transplants to form bone," he says.
The researchers transplanted bone-producing osteoblasts into mice. Some of the osteoblasts were treated with dexamethasone, and some weren't. The investigators found that only the osteoblast cells treated with dexamethasone eventually formed bonelike tissue at the site where they were transplanted. Chemical analysis revealed that the new bone growth had been produced by the transplanted human osteoblast cells and not by cells originating in the mice.
What is unclear, however, is whether this procedure is going to prove to be any better than anything else that is available now or will be available in the near future to stimulate bone growth. Buckwalter says that this research "doesn't tell you if it's any better or worse, more or less expensive, or more or less dangerous" than other options.