A chemical compound that looks like toothpaste but hardens into artificial bone within hours is streamlining the treatment of fractured limbs and offers new hope for aged, fragile bones.
The compound, now in experimental trials at 12 U.S. hospitals, is used to hold splintered bones in place, to fill voids caused by osteoporosis and to replace some of the metal plates and screws that have been used to repair shattered hips, wrists and ankles.
"The material acts as an internal cement by holding the fragments in place," said Dr. Jesse B. Jupiter, a hand surgeon at Massachusetts General Hospital in Boston.
A study to be published today in the journal Science found the compound is virtually identical to natural bone crystals. Once it is placed inside the body, the material hardens within 10 minutes and reaches the compression strength of natural bone within 12 hours. Within weeks, the study showed, the cement is replaced by real bone.
Clinical trials in several U.S. hospitals and in Holland, where the compound is in regular use, show the material has allowed patients to discard casts early--or altogether--and to resume walking more quickly and with less pain.
Brent R. Constantz, co-author of the study and president of Norian Corp. of Cupertino, Calif., which developed the material, said orthopedic surgeons in Holland now use the cement to repair fractures of the wrist, hip and leg and for total joint replacement. The cement also has been used to fill spinal voids caused by osteoporosis.
Jupiter said he has tested the material on patients with a type of wrist fracture and it eliminates the need for incision and weeks in a cast. The doctor also said broken hips that were almost impossible to correct among some older patients are now yielding to the cement.
Constantz said if the studies go well in the United States, his company should receive Food and Drug Administration approval to sell the cement in late 1997.