Pelvic floor muscle training in spinal cord injury and its impact on neurogenic detrusor over-activity and incontinence.

STUDY DESIGN: Two case studies. OBJECTIVES: To determine whether 6 weeks of regular pelvic floor muscle training (PFMT) can improve the strength and endurance of voluntary contractions in incomplete spinal cord injury and reduce neurogenic detrusor over-activity (NDO) and incontinence. SETTING: The London Spinal Cord Injury Centre, Stanmore, London, UK. METHODS: A 6-week programme of PFMT was conducted in two male subjects with stable supra-sacral motor incomplete (AIS C and D) spinal cord injuries. Clinical evaluations before and after training comprised measures of strength and endurance of voluntary pelvic floor contractions both objectively by anal canal-pressure measurements and subjectively using the modified Oxford grading system. NDO was determined by standard urodynamic tests of bladder function and incontinence measured by the International Consultation on Incontinence Questionnaire-Urology. RESULTS: Both subjects improved the strength and endurance of their pelvic floor muscle contractions by over 100% at the end of training. After training, Subject 1 (AIS D) was able to reduce bladder pressure during over-activity almost completely by voluntarily contracting the pelvic floor muscles. Subject 2 (AIS C) achieved a lesser reduction overall after training. Continence improved only in subject 1. CONCLUSION: These case studies provide evidence that a 6-week programme of PFMT may have a beneficial effect on promoting voluntary control of NDO and reduce incontinence in selected cases with a motor incomplete spinal cord lesion.

Light touch and pin prick disparity in the International Standard for Neurological Classification of Spinal Cord Injury (ISNCSCI).

STUDY DESIGN: Retrospective review. OBJECTIVES: The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) assesses cutaneous sensibility through light touch (LT) and sharp-dull discrimination, referred to as pin prick (PP). This project aimed to confirm a tendency for LT to score higher than PP in SCI subjects and discuss possible reasons for such disparity. SETTING: Single site cohort study, the London Spinal Cord Injury Centre, United Kingdom. METHODS: A retrospective analysis of LT and PP scores of 99 spinal cord injury subjects at the time of discharge (median 5 months) from acute care and rehabilitation in the London Spinal Cord Injury Centre was conducted. Subjects were aged 10-88 years (median 44 years; 78 men, 74 traumatic, 25 non-traumatic). There were 40 American Spinal Injury Association (ASIA) Impairment Scale (AIS) A, 7 B, 18 C and 34 D subjects. RESULTS: A disparity (P<0.001) was found between LT (64.5±3.2, mean±s.e.) and PP (54.7±2.9) AIS sensory scores. A similar difference in score (LT>PP) was registered both for traumatic and non-traumatic injury, but was greater for incomplete than for complete injury. Despite the difference, LT was well correlated with PP (R=0.87, P<0.001). Spinal segmental level of injury was determined more frequently by PP alone (43 of 99) than by LT (10 of 99) alone. CONCLUSION: The discrepancies between LT and PP could relate to the greater complexity of the PP test or a difference in the extent of injury to the posterior columns (LT) and spinothalamic (PP) tracts. Further interpretation would benefit from additional electrophysiological sensory tests.

[The role of low urethral mucosal and submucosal blood perfusion in patients with artificial urinary sphincters]. / Importancia de la integridad de la mucosa y submucosa uretral en la continencia de los pacientes con esfínteres urinarios artificiales.

INTRODUCTION: A common complication following insertion of a bulbar AUS is recurrent incontinence, and once other causes have been ruled out, a diagnosis of urethral atrophy is then made. Urethral atrophy probably occurs to a certain degree in all patients with an AUS but the reappearance of incontinence is often attributed to inadequate pressure transfer from the cuff to the atrophic urethra. The normal urethral closure mechanism depends also on passive forces which rely on the integrity of the urethral mucosa and submucosa. MATERIAL AND METHODS: Two groups of patients with a first AUS implant which had been in place for more than 1 year were studied (n = 11). Group I consisted of continent patients (n(I) = 6) whereas Group II had significant incontinence due to urethral atrophy (n(II) = 5). Intraurethral pressures (IP) and blood flux (BF) were measured simultaneously with a micro-tip transducer and a laser Doppler flowmeter in each patient. Positional measurements were recorded proximal, within, and distal to the cuff first with the AUS deactivated and then activated. RESULTS: Group I patients exhibited similar IP and BF at all positions along the urethra. In Group II the IP was similar along the urethra but the BF within the cuff was qualitatively different (non pulsatile) and decreased significantly when compared to either side of the cuff during. DISCUSSION: Continence in patients with artificial urinary sphincters depends not only on the cuff occlusive force but is also dependent on the viability of the mucosal and submucosal tissues. For a given pressure range mucosal and submucosal blood perfusion is determinant. patients with normal blood perfusion would remain continent whereas patients with impaired perfusion would become incontinent.

["Flowsecure" artificial urinary sphincter: a new adjustable artificial urinary sphincter concept with conditional occlusion for stress urinary incontinence]. / Esfínter Urinario Artificial "FlowSecure": un nuevo concepto de esfínter artificial regulable y con oclusión condicional para la incontinencia urinaria de esfuerzo.

INTRODUCTION: To spread de concept of a new artificial urinary sphincter with conditional occlusion for stress incontinence. The new prototype was conceived and designed in The Institute of Urology and Nephrology of London by Professor Craggs M. and Professor Mundy A.R. METHODS: The FlowSecure sphincter consists of an adjustable pressure-regulating balloon, a stress relief reservoir, a control pump and valve assembly unit with self-sealing port and a urethral cuff. The pressure regulating balloon determinates de operating pressure of the device; the pressure is adjustable in the range 0-80 cm H2O and can be altered by injection or removal of normal saline through the self sealing port. The stress relief balloon transmits transient intrabdominal pressure to the cuff during periods of stress. An adjustable circular urethral cuff minimises creasing and possible stress fractures. RESULTS: The device is implanted as a one-piece assembly which is pre-filled with sterile saline. The surgical technique is simple and associated with little handling, reducing risk of infection and potential assembly errors. The adjustable pressure regulating balloon in association with the stress relief reservoir enables the cuff occluding pressure to be set at a low range, therefore reducing the risk for atrophy and erosion. DISCUSSION: The new FlowSecure urinary artificial sphincter with conditional occlusion is designed to provide good continence rates adjusting regulating pressures when needed and conceived to reduce the risk of potential complications associated with excessive occluding pressures and mechanical failures.

["FlowSecure" artificial urinary sphincter: a new adjustable artificial urinary sphincter concept with conditional occlusion for stress urinary incontinence]. / Implantación del esfínter urinario artificial "FlowSecure" en uretra bulbar: descripción de la técnica quirúrgica paso a paso.

INTRODUCTION: We have implanted the FlowSecure artificial sphincter for the first time in October 2006. The prototype was originally conceived and designed by Professor Craggs M. D. and Professor Mundy A.R. Preliminary clinical results were reported in nine patients early this year. Our objective is to spread technique for surgical implantation. METHODS: Combined perineal and abdominal incisions are required for exposure of bulbar urethra, creation of a cavity in the para-vesical space and dissection of a pocket under de scrotal wall. A trocar with a stylet is routed from the abdominal incision to the perineal incision to pass the deflated cuff to the perineal site. The cuff is placed around the urethra and secured with Prolene sutures. After refilling the cuff, fluid is removed from the system until the stress relief balloon becomes just indented (atmospheric pressure 0). The pump is placed in the scrotum and the balloons in the paravesical space. RESULTS: We have implanted our first FlowSecure artificial sphincter in a patient with severe stress incontinence following a T.U.R.P. The surgical technique is simple and associated with little handling. He was discharged from hospital 4 days after the procedure and it was decided that pressurisation was unnecessary. DISCUSSION: Surgical implantation of the new FlowSecure artificial urinary sphincter is an easy procedure in males with stress urinary incontinence. Knigth et al. reported 30 to 40 minutes operating time, 4 days mean hospital stay and unnecessary pressurisation procedure in 3 out of their 9 patients. It seems that their results are reproducible.

Three-dimensional MRI of the male urethrae with implanted artificial sphincters: initial results.

The aim of this study was to develop a method for simultaneous 3D visualization of a new type of artificial urethral sphincter (AUS) and adjacent urinary structures. Serial MR tomograms were acquired from seven men after AUS implantation. 3D reconstruction was performed by thresholding original (positive) and inverted (negative) image intensity and by subsequently fusing positive and negative images. Results show that the bladder, cuff and balloons of the AUS of originally high intensity were imaged in 3D by thresholding the positive datasets. The urethrae and corpora cavernosa penis of originally low intensity were displayed in 3D by thresholding the negative datasets. Fusion of the positive and negative datasets allowed simultaneous visualization of the AUS complex and adjacent urinary structures. All the structures of interest were also clearly seen by interactive multiplanar reformatting. Coronal tomographic datasets provided better 3D and reformatted 2D images than sagittal and transverse datasets. This technique offers a simple means for evaluating the complex urethral anatomy and the AUS, and has potential for improved 3D visualization of many other complex morphological and pathological conditions.

The effects of parasympathetic blocking agents on bladder electromyograms and function in conscious and anaesthetized cats.

Voiding induced in conscious cats by infusion of sterile saline into the bladder via a chronically implanted bladder catheter was stable over many months. Artefact-free recordings of electrical activity obtained from the bladder neck and dome of these preparations during bladder filling and voiding showed characteristic voiding electromyograms but did not permit a functional differentiation. Both voiding and the associated electromyogram were abolished by the ganglion blocking agent, pentolinium. Hyoscine or methyl atropine did not affect the electromyogram but impaired the ability of cats to empty their bladders completely. In anaesthetized cats, ganglion blocking agents prevented a rise in bladder pressure during sacral ventral root stimulation but a hyoscine-sensitive bladder contraction was seen following the period of stimulation. Further stimulation during this post-stimulus rise in intravesical pressure revealed a hyoscine-sensitive stimulus-bound relaxation. Sacral ventral root stimulation relaxed the bladder neck/proximal urethra particularly in the presence of sympathetic tone.

Emerging clinical applications of electrical stimulation: opportunities for restoration of function.

Emerging clinical application of electrical stimulation in three systems is reviewed. In the bladder, stimulation of sacral posterior roots reduces reflex incontinence and significantly improves bladder capacity. With the combination of anterior and posterior root stimulation, bladder control can be achieved without the need for rhizotomy. Preliminary research demonstrates that bladder contractions may also be generated by stimulation of the urethral sensory branch of the pudendal nerve, even after acute spinal cord transection, while inhibition of the bladder and control of urge incontinence can be achieved by stimulation of the whole pudendal nerve. Spinal cord stimulation can modulate the activity of the intrinsic cardiac nervous system involved in the regulation of regional cardiac function and significantly reduce the pain associated with angina pectoris. Finally in the area of upper airway disorders, functional electrical stimulation has great potential for increasing life support as well as for quality of life in chronic ailments, particularly obstructive sleep apnea and dysphagia.

A preliminary report on a new hydraulic sphincter for controlling urinary incontinence.

A new pressure-regulated artificial urinary sphincter (AUS) has been developed which overcomes many of the deficiencies of earlier devices. This implantable AUS comprises a circular occluder cuff and the means to inflate and deflate through a pressure-regulated valve. The device is made from medical-grade silicone rubber and filled with radio-opaque isotonic fluid. A few days before surgery the implant is coated on the outside with an antibiotic-loaded silicone rubber solution. Tests have shown that the regulated pressure was very easily adjusted in situ by injecting or withdrawing the hydraulic fluid through a hypodermic needle penetrating a self-sealing filling port. When set, the regulated pressure remained very stable. The mechanism by which cuff pressure was increased to overcome stress incontinence worked well. Of the five earlier devices (AUS Mk I) implanted, none has survived without mechanical failure. The two latest implants (Mk II), which were rigorously tested for defects before implantation, have been more successful.

[Effects of peripheral functional electrostimulation in obstructive bladder instability]. / Efectos de la electroestimulación funcional periférica en la inestabilidad vesical obstructiva.

INTRODUCTION: The aim of this study was to assess the effects of peripheral functional electrical stimulation (FES) in patients with detrusor instability (DI) secondary to obstructive Benign Prostatic Hyperplasia (BPH). SUBJECTS, MATERIAL & METHODS: Nine patients with urodynamically proven DI secondary to BPH were investigated. Sensory and pudendo-anal reflex thresholds were determined in each patient to individually optimise FES. A standard fill cystometry was then performed and individually optimised FES was given when an unstable detrusor contraction occurred. Non stimulated contractions were used as controls. The effects of FES were analysed by measuring the mean area under the unstable pressure curves with and without FES and were expressed as percentage suppression. RESULTS: The percentage suppression in the mean area under the curves after stimulation was < 10%. There was no statistically significant difference between controls and FES using a two tailed, paired students t-Test (p > 0.1) at 95% confidence level (p > or = 0.05). CONCLUSION: FES did not significantly suppress unstable bladder contractions in patients with DI secondary to BPH. This finding suggests that obstructive DI does not depend on sacral reflex mechanisms and supports the view that it has a peripheral pathophysiological origin (myogenic and/or nerve endings).

Action of 5 Hz repetitive transcranial magnetic stimulation on sensory, motor and autonomic function in human spinal cord injury.

OBJECTIVE: To assess the effectiveness of physiological outcome measures in detecting functional change in the degree of impairment of spinal cord injury (SCI) following repetitive transcranial magnetic stimulation (rTMS) of the sensorimotor cortex. METHODS: Subjects with complete or incomplete cervical (or T1) SCI received real and sham rTMS in a randomised placebo-controlled single-blinded cross-over trial. rTMS at sub-threshold intensity for upper-limb muscles was applied (5 Hz, 900 stimuli) on 5 consecutive days. Assessments made before and for 2 weeks after treatment comprised the ASIA (American Spinal Injuries Association) impairment scale (AIS), the Action Research Arm Test (ARAT), a peg-board test, electrical perceptual test (EPT), motor evoked potentials, cortical silent period, cardiovascular and sympathetic skin responses. RESULTS: There were no significant differences in AIS outcomes between real and sham rTMS. The ARAT was increased at 1h after real rTMS compared to baseline. Active motor threshold for the most caudally innervated hand muscle was increased at 72 and 120 h compared to baseline. Persistent reductions in EPT to rTMS occurred in two individuals. CONCLUSIONS: Changes in cortical motor threshold measures may accompany functional gains to rTMS in SCI subjects. SIGNIFICANCE: Electrophysiological measures may provide a useful adjunct to ASIA impairment scales.

Development of quantitative and sensitive assessments of physiological and functional outcome during recovery from spinal cord injury: a clinical initiative.

The ability to detect physiological changes associated with treatments to effect axonal regeneration, or novel rehabilitation strategies, for spinal cord injury will be challenging using the widely employed American Spinal Injuries Association (ASIA) impairment scales (AIS) for sensory and motor function. Despite many revisions to the AIS standard neurological assessment, there remains a perceived need for more sensitive, quantitative and objective outcome measures. The purpose of Stage 1 of the Clinical Initiative was to develop these tools and then, in Stage 2 to test them for reliability against natural recovery and treatments expected to produce functional improvements in those with complete or incomplete spinal cord injury (SCI). Here we review aspects of the progress made by four teams involved in Stage 2. The strategies employed by the individual teams were (1) application of repetitive transcranial magnetic stimulation (rTMS) to the motor cortex in stable (chronic) SCI with intent to induce functional improvement of upper limb function, (2) a tele-rehabilitation approach using functional electrical stimulation to provide hand opening and grip allowing incomplete SCI subjects to deploy an instrumented manipulandum for hand and arm exercises and to play computer games, (3) weight-assisted treadmill walking therapy (WAT) comparing outcomes in acute and chronic groups of incomplete SCI patients receiving robotic assisted treadmill therapy, and (4) longitudinal monitoring of the natural progress of recovery in incomplete SCI subjects using motor tests for the lower extremity to investigate strength and coordination.

Effects of repeated ejaculations on semen characteristics following spinal cord injury.

STUDY DESIGN: Prospective randomised controlled study. OBJECTIVE: To evaluate the effects of repeated ejaculation on semen characteristics following spinal cord injury (SCI) in a prospective randomised controlled study. SETTING: Spinal Research Centre, Stanmore, UK and Institute of Urology and Nephrology, London, UK. METHODS: A total of 74 patients with SCI above T10 were tested by vibro-ejaculation using a Ferticare penile vibrator (Multicept A/S Horsholm, Denmark) using a standardised technique. The ejaculate was examined according to WHO protocol. The successfully vibro-ejaculated subjects (n = 32) were randomised into a study group (n = 18) and a control group (n = 14). The patients in the study group vibro-ejaculated weekly for 3 months with semen analysis performed at baseline and then monthly. The control group vibro-ejaculated at baseline and at the end of the 3-month period. Two experienced observers performed the semen analysis independently. All measures were compared for statistical significance across the two groups at the beginning and at the end of the 3-month period using a two-tailed student t-test. Significance was determined at the 95% confidence interval (P < 0.05). RESULTS: In total, 10 patients in the study group and nine in the control group have completed the study so far. Six patients have dropped out of the study group and three from the control group for varied reasons. Two patients are currently enrolled in the study and control groups. The morphology and forward progression of sperm shows a statistically significant increase in the study group. The motility improves but is not statistically significant in the study group. No significant adverse effects were reported. CONCLUSIONS: We have shown in this unique randomised controlled study that repeated ejaculation does improve the sperm characteristics in SCI patients. It is suggested that SCI men should undergo repeated ejaculation for at least 3 months before trying intravaginal or intrauterine insemination techniques. If this fails then in vitro fertilisation can be used. This method promotes natural conception, is intimate and cost effective.

A technique for anodally blocking large nerve fibres through chronically implanted electrodes.

If a spinal root of a baboon or rhesus monkey is trapped in an initially loose-fitting silicone rubber channel containing two or more platinum electrodes, electrical pulses sent through these electrodes can stimulate nerve fibres close to the cathode and block the resulting impulses close to the anode. We show (1) how anodal break excitation and excitation of fibres outside the silicone rubber channel can be avoided; (2) that an implant 26 months old behaves like a recent one; (3) that in a root containing somatic motor fibres and parasympathetic fibres, all somatic motor fibres can be blocked and most or all parasympathetic fibres excited but not blocked; (4) that provided that the electrodes pass no net direct current, prolonged stimulation with block can be harmless; (5) how block can be achieved in one direction only along a root; (6) that a peripheral nerve can be blocked by the same techniques.

The real bladder electromyogram.

The nature of bladder electrical activity was investigated in anaesthetised cats and 1 baboon. A time-locked muscle response to sacral ventral root stimulation was most clearly detected within a 10-40 Hz frequency band, the response preceding the rise in intravesical pressure. During reflex voiding only activity in the 10-40 Hz band was consistently related to reflex voiding and to the small contractions leading up to voiding. It is concluded that only a very limited part of the wide band electrical activity recorded from the bladder can be considered genuine electromyogram and that the 10-40 Hz frequency band probably excludes the worst of the artefact. Possible sources of artefact and their relation to changes in intravesical pressure are presented in Table I.

Bladder electromyograms and function in monkeys after atropine.

Voiding induced in conscious monkeys by infusion of sterile saline into the bladder via a chronically implanted bladder catheter was stable over many months. Artefact-free recordings of electrical activity were obtained from the bladder neck and dome of these animals during bladder filling and voiding. Characteristic voiding electromyograms were recorded from both sites but were seen first in the record from the neck. Small doses of methyl-atropine abolished both voiding and the electromyograms; evoked responses to sacral ventral root stimulation were similarly prevented. Therefore the bladders of both man and monkey are very sensitive to atropine, unlike the bladders of most other animals.