Intraspinal nerve rerouting to establish a reflex pathway from skin to spinal cord to bladder is a safe procedure in spinal cord injured patients, but does not allow patients to initiate voluntary micturition.
First author Karl-Dietrich Sievert, MD, and colleagues first performed intraspinal nerve re-routing as a possible treatment to establish bladder function in SCI patients in February 2005. Over a period of 30 months, they operated on a total of eight patients by performing unilateral nerve re-routing from L5 to S3.
No severe complications were encountered intraoperatively or during a mean follow-up of 41 months, and there were some positive findings clinically and in urodynamics testing. However, only one patient achieved micturition with neurostimulation, and that was only with electrical stimulation of the skin during urodynamic testing in the operating room and could not be replicated with vigorous rubbing or scratching of the dermatome any time postoperatively, said Dr. Sievert, professor and vice chairman of urology and director of neuro-urology, incontinence, and reconstructive urology at Eberhard Karls University, Tubingen, Germany.
"We have been unable to replicate the success achieved by Chuan-Guo Xiao, MD, performing intraspinal nerve re-routing to re-establish bladder function in SCI patients, and our experience appears to be consistent with that of a few other urologists in America and Europe, based on some personal communications," Dr. Sievert said. "We are looking into the possibility of a bilateral approach and considering surgery at an earlier stage after SCI to possibly avoid long-term neuro-pathologic changes, as longstanding complete disruption of the spine most likely causes the development of a neurogenic pathology which is currently not reversible."
The eight SCI patients had a mean age of 30 years and had sustained their injury at a mean of 77.3 months (range, 4 to 288 months) prior to the re-routing surgery. All suffered upper motor neuron injury (C6 to Th10) and had no gross pathology at the site of the spinal cord targeted in the surgery.
The surgeries were performed using the same technique as that developed by Dr. Xiao, and in fact, the first two cases were performed with Dr. Xiao present in the OR.
"Dr. Xiao reported an 80% success rate with intraspinal nerve re-routing in SCI patients, and so we would have expected a positive outcome in at least one of the two cases performed under his supervision," Dr. Sievert told Urology Times.
Some positive effects noted
Although the surgery failed to achieve its primary goal for any of the eight SCI patients, there were some positive effects noted in urodynamic studies, for which there was a mean follow-up of 27 months. Mean maximum bladder capacity decreased from 346 mL preoperatively to 293 mL after the surgery, and the maximum detrusor pressure decreased from 61 cm H2O to 40 cm H2O. A few patients benefited with fewer bladder infections and improvement in bowel movements. The surgery was associated with no significant benefits on bladder sensitivity, catheterization frequency, or urinary incontinence occurrences.