Post date: Aug 16, 2011 7:53:16 PM
Scientists in the United States have developed an organic replacement for herniated discs, offering a much improved solution for sufferers of back and neck pain. The researchers say the new discs, which have been successfully implanted in rats, grows with the body's natural tissue and could help millions of patients around the world.
NEW YORK CITY, NEW YORK UNITED STATES. REUTERS - For Dr. Roger Hartl, a neurosurgeon at Weill Cornell Medical College in New York, discectomy surgery is a routine procedure. For his patients, it's usually the last resort to relieve the pain caused by a herniated disc, a common cause of back pain for millions of people around the world.
Hartl is also part of a team comprising researchers at Cornell University, who believe conventional discectomy - where damaged discs are replaced by plastic or metal implants - may soon be a thing of the past.
They've developed an organic spinal disc with tissue harvested from sheep spines. In experiments with laboratory rats, they've demonstrated that the bioengineered discs can replace diseased or damaged discs with greater efficacy and a longer life-span than artificial ones.
Dr. Hartl regularly treats patients who suffer from degenerative disc disease by performing discectomies. He says the new bioengineered discs could make a significant difference in his patients' quality of life.
"What we are doing right now is removing the disc that is pushing on the spinal chord. So when we do that we end up with a gap between the bones where disc is usually situated. With the biological disc implant that we're working on. The treatment here would be to have a grown disc and implant that disc into the defect that we're creating to replace the disc that we're removing.", he said.
Conventional implants used in the procedure are made of metal and plastic and can cause patients to lose some degree of mobility. Hartl says they they often deteriorate over time and can become loose or fail, requiring further surgery.
"The options that we have right now available other than a simple discectomy are implants that eventually lead to a fusion and the biological disc solution that we are working on really avoids that. It's really an implant that we insert into the spine, that replicates exactly the function of the normal spinal disc and actually integrates itself over time with the anatomy and actually grows with the patient and remodels itself as the patient goes on.", he said.
The new discs are made of two polymers. In the center is an alginate, which is surrounded by a firmer and more stable ring of collagen that wraps around the outside of the disc to help keep it weighted, like real spinal discs.
Dr. Lawrence Banassar grew the biological discs at a lab at Cornell University. He and his team conducted tests by inserting them into the spines of rats whose discs had been removed. They were monitored with MRI and CT scans. The studies showed that the animals grew new cells that integrated into the spine.
The researchers say that initially it wasn't clear how the complicated structures would survive due to their lack of blood vessels and ability to take in oxygen.
"It was very unclear when we started doing this research how this would pan out in an environmental setting with a bioengineered disc. Would that lead to faster degradation and death of those discs or would they be able to survive and proliferate? And they did. That's the biggest surprise of our research so far is that we were able to create an organ that is essentially devoid of any blood vessels that is relatively large but that survives and actually improves and gets better over time."
The scientists say their findings offer hope to patients that a natural implant could be available for those suffering from spinal injury or herniated discs a few years time.