Experimental And Clinical Study On Atonic Bladder Function Reconstruction By Spinal Nerve Microanastomosis After Spinal Cord Injury

Part one A epidemiology investigation on the condition of spinal cord injury and rehabilitation exercise instruction【Objective】To survey the condition of spinal cord injury and rehabilitation exercise, which is significant to enhance and instruct the appropriate functional exercise in spinal cord injury.【Methods】Sixty-seven paraplegias consent to accept the investigation from July 2002 to December 2003.They were inquired according to the questionaire created by study group. In addition to the basic living condition ,the urination and defecation , urinary tract infection ,bedsore and rehabilitation exercise were mainly investigated .The examinations,including blood routine ,urine routine,renal function and ultrasound examination of urinary system which using some kind of apparatus, were carried out accompanied by personnel .The other condition were accomplished by answering the questionnaire.【Results】Of the spinal cord injuried patients ,the middle-age were more common and the mean age was 45.7 . The male were injuried much more easily than the female. The ratio of the male was 68.7 percent while the female was 31.3 percent .The trauma was the main cause of spinal cord injury which accounted 64.2 percent of all injury causes in these patients. The most common level of injuried spine was thoracic-lumber spine which accounted 50.7 percent. Only 7.5 percent patients had ever undertook systemic functional exercises, while patients accounted 77.6 percent had no exercises. Bladder dysfunction was most common in spinal cord injury. It usually damaged renal dysfunction and affected the quality of life and the life-expectancy. Only 16.4 percent had ever received doctor's instruction about bladder training, 68.7 percent had never trained bladder micturition . It was obviously that we should urgent to enforce the bladder function training in spinal cord injury.【Conclusions】According to the survey and analysis ,we proposed the plan including not only paying attention to motor function training, micturition training and bedsore prevention training, but also complication prevention ,aid appliance and family no obstacle construction . With the help of doctor ,rehabilitation worker , engineering technicians and the paralysics'family ,the spinal cord injuried patients can implement the true rehabilitationPart Two Experimental modeling and long-term function study on the artificial bladder reflex arc established by spinal nerve root microanastomosis in therapy of atonic bladder after spinal cord injury【Objective】To establish the artificial bladder reflex arc by the normal body reflex pathway above the horizon of spinal cord injury to reinnervate the flaccid bladder and restore bladder micturition function.【Methods】The anatomy characteristic of sacral nerve root were observed . It is achieved by intradural microanastomosis of the L6 ventral root to S2 ventral root. After axonal regeneration ,the artificial reflex pathway was reestablished. Long-term function of the reflex arc was observed by nerve electrophysiological experiment ,detrusor electromyography experiment and urodynamic testing at 8 months'postoperation.【Results】In the canine anatomy, only three sacral nerve root innervate the pelvic cavity organ system. The diameter of S1 and S2 nerve root are 1.3mm ,but S3 nerve root is 0.6mm .For bladder innervation , S2 nerve root is most dominant,while for sphincter S1 nerve root is most dominant. Trains of the stimuli(200μV 5ms) on the left L6 dorsal root and nerve anastomosized site resulted in motor evoked potential recorded from the disal to the anastomosized site before and after the spinal cord destroyed horizontally between S1 and S4 segment level in two Beegle dogs.The figure and amplitude of the motor evoked potential were similar to the normal control and general stability which stated noninterventional wave. Urodynamic testing display quick increase of bladder pressure but minor raise in abdominal pressure .This manisfested that detrusor of bladder not abdominal muscle mainly contributed intravesical pressure rising .【Conclusions】Long-term observation of nerve electrophysiological experiment ,detrusor electromyography experiment and urodynamic testing stated that the new artificial reflex arc had been established successfully. The somatic motor axons can regenerate into the parasympathetic endoneurial tubes of autonomic nerve.Part Three HRP retrogradation tracing and morphological study on artificial reflex arc reconstructed for atonic bladder by spinal nerve root microanastomosis after spinal cord injury【Objective】To study new artificial reflex pathway established by normal reflex above the level of spinal cord injury and reinnervated by the somatic motor nerve regenerating through the spinal nerve, and to explore the neural morphological basis of the artificial bladder reflex arc how to control micturition.【Methods】It is achieved by intradural microanastomosis of the L6 ventral root to S2 ventral root . After axonal regeneration ,the new nerve pathway was established. So HRP retrograde tracing was carried out after the spinal cord was destroyed horizonally between S1 and S4 segement level at 8 months postoperative. And regenerative nerve was also observed under light microscopy. The wall of urinary bladder and terminal cone of spinal cord were respectively handled by HE dyeing and Nissl's staining .【Results】It was seen that HRP labeled cells was found in L6 ventral horn on the experimental side under light microscopy. The regenerative nerve fiber of L6 ventral root had grown through the anastomotic site to distal nerve root. The cell of bladder wall lined up tightly in order and was no cataplasia .Nissl's staining showed that tigroid body in neuron and neuroglia cell stained lightly ,decrease or disappear after spinal cord injury.【Conclusions】The new bladder reflex arc by spinal nerve anastomosis between L6 and S2 ventral root had been established according to the HRP retrogradation tracing and morphological observation .The micturition centre had been transferred from terminal cone of spinal cord. The somatic motor axons above the lumbosacral injuried level can innervate bladder parasympathetic ganglion cells and thereby transfer somatic reflex activity to the bladder smooth muscle.Part Four Clinical study in establishing an artificial reflex arc to restore controlled micturition of atonic bladder after spinal cord injury【Objective】To study the establishment of an new artificial bladder reflex arc for controlled micturition function in terminal cone of spinal cord injury .【Methods】Seven patients in conus medullaris injury were included by unilateral microanastomosis of the T10/T11 ventral root to S2 ventral root. After several months of axonal regeneration,the micturition function were examined clinically and urodynamically.【Results】The follow-up time were longer because of anastomotic nerve regeneration .Two patients were undertook operation more early than other cases. One female case was put on intermittent urethral catheterization and gradually began to urinate spontaneously after 18 months postoperation. The patient has been followed up for 55 months and now she does not need any urethral catheterization and able to urinate completely by herself 4~5 times one day. The urinary output is 500-800 ml one time. She has had the sensation of bladder fullness, and urinate spontaneously and powerfully without any difficulty. The results of urodynamic study showed that detrusor has nerve reflex while the external sphincter is denervated. It is thus clear that the acquired function of urination was mainly caused by detrusor contraction, rather by compressing the bladder through abdominal muscle. The male patient of two cases didn't acquire the controlled micturition after following up four years. The other cases were following up because of later operation and nerve regeneration.【Conclusions】Establishing of an new artificial reflex arc may effective for controlled micturition in conical SCI.