Gels are becoming the tools of the future in spine surgery and back pain management

Jun 20 2011
Spine surgery is increasingly at the crossroads of medicine and technology, and the latest discovery from researchers at the University of California Davis is there to prove it.

One of the most dangerous side effects of back surgery are spinal fluid leaks through minuscule holes that may be left by surgical instruments. Not only can these leaks be painful in themselves, but they also increase the risk of infections such as meningitis. Often, patients who experience spinal fluid leaks need to undergo a second surgery to repair them, resulting in more wounds that need to heal and additional recovery time.

So it is no wonder that scientists have been hard at work to figure out ways to prevent such leaks in the first place.

In recent months, 24 medical centers throughout the U.S. tested the effectiveness of a hydrogel sealant made out of polyethylene glycol (PEG).

Operating surgeons used the substance as a complement during the suturing of the dura, which is a sheath inside the spinal column that encloses and protects the spinal cord. Any holes left in the dura as a result of a surgical intervention can cause the spinal fluid to leak out.

The researchers found that 100 percent of the patients who received the PEG hydrogel sealant had a watertight closure - meaning no leaks - as opposed to only 64 percent of those who received standard care, which included using additional stitches to close the holes.

Kee Kim, an associate professor of neurological surgery at the School of Medicine at UC Davis and chief of spinal neurosurgery and co-director of the UC Davis Spine Center, says the gel is not only effective but also safe because it is synthetic. This eliminates any risk of disease transmission or immune system rejection issues that are sometimes encountered with animal-derived or human-donated tissue.

The gel, which is a liquid that solidifies and creates a tight seal when it comes into contact with the body, was approved for use by the Food and Drug Administration in 2010.

The current study, which was published in the journal Spine, follows another project from researchers at the University of Manchester in the UK who successfully tested the use of an elastic gel to relieve chronic back pain symptoms.

Based on nanoscopic polymer particles that are injected into the affected part of the spine, the gel was shown in clinical studies to be able to replace an intervertebral disc. This property stems from its flexibility that allows for natural movements of the spine. The gel is also durable, which is a basic requirement for an implant. Finally, just like the PEG gel, it is synthetically manufactured.

Individuals who require disc replacement are typically those who have been diagnosed with disc degeneration, bulging or herniation, conditions that account for most chronic back pain symptoms. Up until now, many of these patient have only been able to find sufficient relief with invasive spine surgery.