The understanding of the impact of tethered cord syndrome (TCS) on the physiology of the colorectal area is limited. Our aim was to describe anorectal and colonic motility in children with TCS and compare the findings to those of children with functional constipation (FC).

We conducted a retrospective review of children with TCS who had an anorectal manometry (ARM) performed at our institution from January 2011 to September 2023. We recorded demographics, medical and surgical history, clinical symptoms, and treatment at time of ARM, ARM findings (resting pressure, push maneuver, rectal sensation, rectoanal inhibitory reflex [RAIR], and RAIR duration), and the final interpretation of colonic manometry (CM) if performed. We identified age and sex-matched control groups of children with FC.

We included 24 children with TCS (50% female) who had ARM testing (median age at ARM 6.0 years, interquartile range 4.0-11.8 years). All children had constipation at time of ARM. Nineteen children had detethering surgery before ARM was performed. No significant differences in ARM parameters were found between children who had detethering surgery before ARM and children with FC. Among the 24 children, 14 also had a CM performed (13/14 after detethering surgery). No significant differences in colonic motility were found between children with a history of TCS and children with FC.

Anorectal physiology and colonic motility are similar between children with a history of TCS and children with FC, suggesting that the underlying pathophysiology of defecatory disorders in children with and without history of TCS is similar.

Effect of biofeedback on improving anorectal manometric parameters in incomplete spinal cord injury is unknown. A short-term biofeedback program investigated any effect on anorectal manometric parameters without correlation to bowel symptoms.

This prospective uncontrolled interventional study comprised three study subject groups, Group 1: sensory/motor-complete American Spinal Injury Association Impairment Scale (AIS) A SCI (n = 13); Group 2 (biofeedback group): sensory incomplete AIS B SCI (n = 17) (n = 3), and motor-incomplete AIS C SCI (n = 8), and AIS D SCI (n = 6); and Group 3: able-bodied (AB) controls (n = 12). High-resolution anorectal manometry (HR-ARM) was applied to establish baseline characteristics in all subjects for anorectal pressure, volume, length of pressure zones, and duration of sphincter squeeze pressure. SCI participants with motor-incomplete SCI were enrolled in pelvic floor/anal sphincter bowel biofeedback training (2 × 6-week training periods comprised of two training sessions per week for 30-45 min per session). HR-ARM was also performed after each of the 6-week periods of biofeedback training.

Compared to motor-complete or motor-incomplete SCI participants, AB subjects had higher mean intra-rectal pressure, maximal sphincteric pressure, residual anal pressure, recto-anal pressure gradient, and duration of squeeze (p < 0.05 for each of the endpoints). No significant difference was evident at baseline between the motor-complete and motor-incomplete SCI groups. In motor-incomplete SCI subjects, the pelvic floor/anal sphincter biofeedback protocol failed to improve HR-ARM parameters.

Biofeedback training program did not improve anal manometric parameters in subjects with motor-incomplete or sensory-incomplete SCI. Biofeedback did not change physiology, and its effects on symptoms are unknown.

Utility of biofeedback is limited in patients with incomplete spinal cord injury in terms of improving HR-ARM parameters.

Faecal incontinence, which is defined by the unintentional loss of solid or liquid stool, has a worldwide prevalence of ≤7% in community-dwelling adults and can markedly impair quality of life. Nonetheless, many patients might not volunteer the symptom owing to embarrassment. Bowel disturbances, particularly diarrhoea, anal sphincter trauma (obstetrical injury or previous surgery), rectal urgency and burden of chronic illness are the main risk factors for faecal incontinence; others include neurological disorders, inflammatory bowel disease and pelvic floor anatomical disturbances. Faecal incontinence is classified by its type (urge, passive or combined), aetiology (anorectal disturbance, bowel symptoms or both) and severity, which is derived from the frequency, volume, consistency and nature (urge or passive) of stool leakage. Guided by the clinical features, diagnostic tests and therapies are implemented stepwise. When simple measures (for example, bowel modifiers such as fibre supplements, laxatives and anti-diarrhoeal agents) fail, anorectal manometry and other tests (endoanal imaging, defecography, rectal compliance and sensation, and anal neurophysiological tests) are performed as necessary. Non-surgical options (diet and lifestyle modification, behavioural measures, including biofeedback therapy, pharmacotherapy for constipation or diarrhoea, and anal or vaginal barrier devices) are often effective, especially in patients with mild faecal incontinence. Thereafter, perianal bulking agents, sacral neuromodulation and other surgeries may be considered when necessary.

Our objectives were to better characterize the colorectal function of patients with Spina Bifida (SB). Patients with SB and healthy volunteers (HVs) completed prospectively a standardized questionnaire, clinical evaluation, rectal barostat, colonoscopy with biopsies and faecal collection. The data from 36 adults with SB (age: 38.8 [34.1-47.2]) were compared with those of 16 HVs (age: 39.0 [31.0-46.5]). Compared to HVs, rectal compliance was lower in patients with SB (p = 0.01), whereas rectal tone was higher (p = 0.0015). Ex vivo paracellular permeability was increased in patients with SB (p = 0.0008) and inversely correlated with rectal compliance (r = - 0.563, p = 0.002). The expression of key tight junction proteins and inflammatory markers was comparable between SB and HVs, except for an increase in Claudin-1 immunoreactivity (p = 0.04) in SB compared to HVs. TGFβ1 and GDNF mRNAs were expressed at higher levels in patients with SB (p = 0.02 and p = 0.008). The levels of acetate, propionate and butyrate in faecal samples were reduced (p = 0.04, p = 0.01, and p = 0.02, respectively). Our findings provide evidence that anorectal and epithelial functions are altered in patients with SB. The alterations in these key functions might represent new therapeutic targets, in particular using microbiota-derived approaches.Clinical Trials: NCT02440984 and NCT03054415.

To investigate whether the urogenital and bowel functional gains previously demonstrated post-locomotor step training after chronic spinal cord injury could have been derived due to weight-bearing alone or from exercise in general.

Prospective cohort study; pilot trial with small sample size.

Urogenital and bowel scientific core facility at a rehabilitation institute and spinal cord injury research center in the United States.

Men and women (N=22) with spinal cord injury (American Spinal Injury Association Impairment Scale grades of A-D) participated in this study.

Approximately 80 daily 1-hour sessions of either stand training or nonweight-bearing arm crank ergometry. Comparisons were made with previously published locomotor training data (step; N=7).

Assessments at both pre- and post-training timepoints included cystometry for bladder function and International Data Set Questionnaires for bowel and sexual functions.

Cystometry measurements revealed a significant decrease in bladder pressure and limited improvement in compliance with nonweight-bearing exercise but not with standing. Although International Data Set questionnaires revealed profound bowel dysfunction and marked deficits in sexual function pretraining, no differences were identified poststand or after nonweight-bearing exercise.

These pilot trial results suggest that, although stand and weight-bearing alone do not benefit pelvic organ functions after spinal cord injury, exercise in general may contribute at least partially to the lowering of bladder pressure and the increase in compliance that was seen previously with locomotor training, potentially through metabolic, humoral, and/or cardiovascular mechanisms. Thus, to maximize activity-based recovery training benefits for functions related to storage and emptying, an appropriate level of sensory input to the spinal cord neural circuitries controlling bladder and bowel requires task-specific stepping.

Objective: To provide an overview of clinical assessments and diagnostic tools, self-report measures (SRMs) and data sets used in neurogenic bladder and bowel (NBB) dysfunction and recommendations for their use with persons with spinal cord injury /disease (SCI/D).Methods: Experts in SCI/D conducted literature reviews, compiled a list of NBB related assessments and measures, reviewed their psychometric properties, discussed their use in SCI/D and issued recommendations for the National Institutes of Health (NIH), National Institute of Neurological Disorders and Stroke (NINDS) Common Data Elements (CDEs) guidelines.Results: Clinical assessments included 15 objective tests and diagnostic tools for neurogenic bladder and 12 for neurogenic bowel. Following a two-phase evaluation, eight SRMs were selected for final review with the Qualiveen and Short-Form (SF) Qualiveen and the Neurogenic Bowel Dysfunction Score (NBDS) being recommended as supplemental, highly-recommended due to their strong psychometrics and extensive use in SCI/D. Two datasets and other SRM measures were recommended as supplemental.Conclusion: There is no one single measure that can be used to assess NBB dysfunction across all clinical research studies. Clinical and diagnostic tools are here recommended based on specific medical needs of the person with SCI/D. Following the CDE for SCI studies guidelines, we recommend both the SF-Qualiveen for bladder and the NBDS for bowel as relatively short measures with strong psychometrics. Other measures are also recommended. A combination of assessment tools (objective and subjective) to be used jointly across the spectrum of care seems critical to best capture changes related to NBB and develop better treatments.

Neurogenic bowel dysfunction (NBD) is a highly prevalent problem after spinal cord injury, with potential for significant impact on health and quality of life. The international standards to document remaining autonomic function after SCI were developed to standardize communication between professionals regarding neurogenic bowel and other autonomic function after SCI. To improve understanding of the bowel subsection, illustrative cases are presented.

Three cases are presented which illustrate differences in presentation and scoring of the elements in the data set based upon varying injury severity and location.

Determination of neurologic level of injury is insufficient for assessment of autonomic function and there is no direct method of assessment. Hence, surrogate makers are needed. The bowel subsection of the International standards to document remaining autonomic function in persons with SCI is an easy-to-use tool for this purpose.

Narrative review.

The purpose is to review the organisation of the nerve pathways that control defecation and to relate this knowledge to the deficits in colorectal function after SCI.

A literature review was conducted to identify salient features of defecation control pathways and the functional consequences of damage to these pathways in SCI.

The control pathways for defecation have separate pontine centres under cortical control that influence defecation. The pontine centres connect, separately, with autonomic preganglionic neurons of the spinal defecation centres and somatic motor neurons of Onuf's nucleus in the sacral spinal cord. Organised propulsive motor patterns can be generated by stimulation of the spinal defecation centres. Activation of the somatic neurons contracts the external sphincter. The analysis aids in interpreting the consequences of SCI and predicts therapeutic strategies.

Analysis of the bowel control circuits identifies sites at which bowel function may be modulated after SCI. Colokinetic drugs that elicit propulsive contractions of the colorectum may provide valuable augmentation of non-pharmacological bowel management procedures.

To investigate whether MR-defecography can be employed in sensorimotor complete spinal cord injury (SCI) subjects as a potential diagnostic tool to detect defecational disorders associated with neurogenic bowel dysfunction (NBD) using standard parameters for obstructed defecation.

In a prospective single centre clinical trial, we developed MR-defecography in traumatic sensorimotor complete paraplegic SCI patients with upper motoneuron type injury (neurological level of injury T1 to T10) using a conventional 3T scanner. Defecation was successfully induced by eliciting the defecational reflex after rectal filling with ultrasonic gel, application of two lecicarbon suppositories and digital rectal stimulation. Examination was performed with patients in left lateral decubitus position using T2-weighted turbo spin echo sequence in the sagittal plane at rest (TE 89ms, TR 3220ms, FOV 300mm, matrix 512×512, ST 4mm) and ultrafast-T2-weighted-sequence in the sagittal plane with repeating measurements (TE 1.54ms, TR 3.51ms, FOV 400mm, matrix 256×256, ST 6mm). Changes of anorectal angle (ARA), anorectal descent (ARJ) and pelvic floor weakness were documented and measured data was compared to reference values of asymptomatic non-SCI subjects in the literature to assess feasibility.

MR-defecography provides evaluable imaging sequences of the induced evacuation phase in SCI patients. Measurement results for ARA, ARJ, hiatal width (H-line) and hiatal descent (M-line) deviate significantly from reference values in the literature in asymptomatic subjects without SCI. The overall mean values in our study for SCI patients were: ARA (rest) 127.3°, ARA (evacuation) 137.6°, ARJ (rest) 2.4cm, ARJ (evacuation) 4.0cm, H-line (rest) 7.6cm, H-line (evacuation) 8.1cm, M-line (rest) 2.6cm, M-line (evacuation) 4.2cm.

MR-defecography is feasible in sensorimotor complete SCI patients. Individual MR-defecography findings may help to determine specific therapeutical options for respective patients suffering from severe NBD.

Longitudinal study with postal survey.

To describe changes in the patterns of neurogenic bowel dysfunction and bowel management in a population of people with spinal cord injury (SCI) followed for two decades.

Members of the Danish SCI Association.

In 1996, a validated questionnaire on bowel function was sent to the members of the Danish SCI Association (n=589). The same questionnaire was sent to all the surviving members in 2006 (n=284) and in 2015 (n=178). A total of 109 responded to both the 1996 and 2015 questionnaires.

Comparing data from 2015 with those from the exact same participants in 1996, the proportion of respondents needing more than 30 min for each defaecation increased from 21 to 39% (P<0.01), the use of laxatives increased (P<0.05) and the proportion considering themselves very constipated increased from 19 to 31% (P<0.01). In contrast, the proportion suffering from faecal incontinence remained stable at 18% in 1996 and 19% in 2015. During the 19-year period, there had been no significant change in the methods for bowel care, but 22 (20%) had undergone surgery for bowel dysfunction, including 11 (10%) who had some form of stoma.

Self-assessed severity of constipation increased but quality of life remained stable in a cohort of people with SCI followed prospectively for 19 years. Methods for bowel care remained surprisingly stable but a large proportion had undergone stoma surgery.

Supraconal spinal cord injury (SCI) and lower motor neurone spinal cord injury (LMN-SCI) cause bowel dysfunction; colorectal compliance may further define its pathophysiology. The aim of this study was to investigate rectal (RC) and sigmoid (SC) compliance and anorectal physiology parameters, in these subjects.

Twenty-four SCI subjects with gut symptoms (14 RC, 10 SC) and 13 LMN-SCI subjects (9 RC, 4 SC) were compared with 20 spinal intact controls (10 RC, 10 SC). Staircase distensions were performed using a barostat. Anorectal manometry, including rectoanal inhibitory reflex (RAIR) measurement, was performed in all. Data presented as mean±standard error (SCI/LMN-SCI vs. controls).

SCI subjects had a higher RC (17.0±1.9 vs. 10.7±0.5 ml/mm Hg, P<0.05) and SC (8.5±0.6 vs. 5.2±0.5 ml/mm Hg, P=0.002). LMN-SCI subjects had a lower RC (7.3±0.7 ml/mm Hg, P=0.0021) while SC was unchanged (8.3±2.2 ml/mm Hg, P>0.05). Anal resting pressure was decreased in SCI (55±5 vs. 79±7 cmH2O, P=0.0102). Anal squeeze pressure was decreased in LMN-SCI (76±13 vs. 154±21 cmH2O, P=0.0158). In SCI and LMN-SCI, the amplitude reduction of the RAIR was greater (62±4% and 70±6% vs. 44±3%, P=0.0007).

Colorectal compliance abnormalities may explain gut symptoms: increased RC and SC contributing to constipation in SCI, reduced rectal compliance contributing to fecal incontinence (FI) in LMN-SCI. Reduced resting anal pressure in SCI and reduced anal squeeze pressure in LMN-SCI along with a greater RAIR amplitude reduction may be factors in FI. These co-existing abnormalities may explain symptom overlap, and represent future therapeutic targets to ameliorate neurogenic bowel dysfunction.

Spinal cord injury (SCI) results not only in motor and sensory deficits but also in autonomic dysfunctions. The disruption of connections between higher brain centers and the spinal cord, or the impaired autonomic nervous system itself, manifests a broad range of autonomic abnormalities. This includes compromised cardiovascular, respiratory, urinary, gastrointestinal, thermoregulatory, and sexual activities. These disabilities evoke potentially life-threatening symptoms that severely interfere with the daily living of those with SCI. In particular, high thoracic or cervical SCI often causes disordered hemodynamics due to deregulated sympathetic outflow. Episodic hypertension associated with autonomic dysreflexia develops as a result of massive sympathetic discharge often triggered by unpleasant visceral or sensory stimuli below the injury level. In the pelvic floor, bladder and urethral dysfunctions are classified according to upper motor neuron versus lower motor neuron injuries; this is dependent on the level of lesion. Most impairments of the lower urinary tract manifest in two interrelated complications: bladder storage and emptying. Inadequate or excessive detrusor and sphincter functions as well as detrusor-sphincter dyssynergia are examples of micturition abnormalities stemming from SCI. Gastrointestinal motility disorders in spinal cord injured-individuals are comprised of gastric dilation, delayed gastric emptying, and diminished propulsive transit along the entire gastrointestinal tract. As a critical consequence of SCI, neurogenic bowel dysfunction exhibits constipation and/or incontinence. Thus, it is essential to recognize neural mechanisms and pathophysiology underlying various complications of autonomic dysfunctions after SCI. This overview provides both vital information for better understanding these disorders and guides to pursue novel therapeutic approaches to alleviate secondary complications.

Clinical study.

To explore how supraconal spinal cord injury (SCI) affects colorectal emptying at defecation. Further, to relate findings to subject symptomatology expressed by bowel function scores and gastrointestinal transit time (GITT).

Aarhus University Hospital, Denmark.

Colorectal contents were marked by oral intake of (111)In-coated resin pellets. Movement of stools at defecation was assessed by comparing scintigrams performed before and just after defecation. Results from 15 subjects with SCI (14 males, median age=47 years (range: 22-74 years), SCI level: C5-Th9) were compared with those from 16 healthy volunteers (12 males, median age=31 years (range: 24-42 years)). Bowel symptoms were described from standard symptom scores, and GITT was assessed by radiopaque markers.

Median emptying at defecation was 31% of the rectosigmoid (range: 0% to complete emptying of the rectosigmoid and 49% of the descending colon) in subjects with SCI and 89% of the rectosigmoid (range: 53% to complete emptying of the rectosigmoid and the descending colon, and 3% of the transverse colon) in the control group (P<0.01). Colorectal emptying at defecation was associated with the St Mark's fecal incontinence score (P=0.02) but not with the Cleveland constipation score (P=0.17), the neurogenic bowel dysfunction score (P=0.12) or GITT (P=0.99).

Supraconal SCI results in significantly reduced emptying of stools at defecation. This is independent of changes in GITT.

Bowel dysfunction amongst multiple sclerosis (MS) and spinal cord injury (SCI) patients often manifests as fecal incontinence (FI) or constipation, but the pathophysiology is poorly understood. Anorectal physiology provides an objective assessment of lower bowel functions and is increasingly being used in clinical practice.

The purpose of this study was to correlate symptoms of bowel dysfunction in patients with spinal cord disease with findings in anorectal physiology. We hypothesized that specific abnormalities will correlate with symptoms: prolonged recto-anal inhibitory reflex in patients with incontinence and decreased rectal mucosal blood flow in patients with constipation.

Forty-nine patients with MS (35 with predominant FI and 14 constipation), 46 supraconal SCI (mixed symptom load), and 21 healthy volunteers matched for age and sex were studied. Subjects completed validated constipation and FI symptom questionnaires. Patients underwent standard anorectal physiology, including assessment of rectal mucosal blood flow and recto-anal inhibitory reflex (RAIR).

Severity of constipation correlates significantly with distension sensitivity (urge volume [r = 0.68, p = 0.002] and maximal volume [r = 0.39, p = 0.03]). Severity of constipation also correlated with diminished rectal mucosal blood flow in both patient groups (r = -0.51, p = 0.006). In both groups, constipation correlated with diminished relaxation of the sphincters in the RAIR whilst fecal incontinence correlated with a prolonged duration of RAIR (r = 0.33, p = 0.009) and recovery phase (r = 0.37, p = 0.05).

Bowel symptoms in patients with MS and SCI correlate with specific alterations of anorectal physiology. This provides objective assessment of bowel symptoms and may allow tailored treatment to individual patients.

Intestinal motor and sensory dysfunctions in traumatic complete or incomplete spinal cord injury (SCI) are frequent and result in altered mechanisms of defecation. The aim of this study is to investigate sigmoid compliance and perception in chronic SCI patients. Sigmoid responses to fixed-tension distentions were assessed using a tensostat in six patients (six men, 42 ± 4 years) with chronic complete transection of the spinal cord (high-SCI; five tetraplegic C5-C7 and one paraplegic T4-T6) and impaired evacuation (i.e. constipation). A group of 10 healthy individuals (six men, 25 ± 1 years) served as controls. SCI patients had higher sigmoid compliance at the highest distention level than the controls (10.3 ± 2.4 vs. 5.1 ± 0.8 ml/mmHg; P<0.05). Perception scores at first sensation were higher in SCI patients (2.3 ± 0.7 vs. 1.1 ± 0.1; P<0.05), but were not different at the highest distention levels (3.7 ± 0.8 vs. 3 ± 1; NS). The most commonly reported sensation by patients was distention/bloating and was referred less commonly to the hypogastrium compared with distention/bloating in controls. An increased sigmoid compliance can be detected in constipated SCI patients. The preservation of some degree of visceral sensations, although abnormally referred, could imply the occurrence of sensory input remodeling at the spinal level.

We previously showed that approximately 10% of patients with intractable constipation have spinal abnormalities without any other physical findings. Given that spinal magnetic resonance imaging is costly and often requires deep sedation in children, it would be useful to find a screening tool to determine who has a higher likelihood of having a spinal abnormality. The aim of the study was to determine whether anorectal manometry is a useful screening test in predicting which patients will have abnormal spinal MRIs.

This is a case-control study comparing the anorectal manometries of 10 children with constipation who had abnormal spinal MRIs (cases) to the manometries of 10 age-matched children with normal MRIs (controls).

The maximum relaxation of the sphincter after balloon distention was achieved with a significantly smaller balloon in the cases as compared with the controls (35 ± 20 vs 60 ± 23 mL; P = 0.02). The dose-response curve of sphincter relaxation at different balloon distention was shifted to the left in patients with spinal lesions. Anal spasms after balloon distention were noted in 60% of the patients with abnormal magnetic resonance images compared with 0% of the controls (P < 0.003). There were no other differences.

Patients with spinal cord abnormalities may show changes in anorectal manometry. Anal spasms on anorectal manometry are significant predictors of spinal abnormalities. Also, patients with spinal abnormalities have maximum sphincter relaxations with smaller balloon sizes. Further studies are needed to determine the utility of anorectal manometry as a screening test for spinal abnormalities in patients with constipation.

Constipation in patients with mild spinal cord disease is not well investigated yet. We aimed to investigate anorectal function and the effect of biofeedback therapy in constipated patients with mild spinal cord diseases.

A total of 14 constipated patients with myelopathy and 32 with radiculopathy were enrolled retrospectively. All patients were able to walk independently. The control group comprised of 100 constipated patients without any neurologic problem. Colonic transit time and the presence of dyssynergia were assessed before biofeedback therapy. All patients answered structured questionnaires on constipation, before and after biofeedback therapy.

The mean rectosigmoid colonic transit time of the myelopathy group was significantly delayed (myelopathy, 18.6 ± 14.6 h; radiculopathy, 12.8 ± 11.9 h; control, 9.6 ± 11.2 h; p = 0.032). Delay in total colonic transit time was more frequent in the myelopathy group (myelopathy, 57.1%; radiculopathy, 23.3%; control, 18.5%; p = 0.004). On anorectal manometry, the squeezing pressure of the anal sphincter was decreased in the myelopathy group (myelopathy, 132.3 ± 73.3 mmHg; radiculopathy, 179.9 ± 86.1 mmHg; control 200.4 ± 82.4 mmHg; p < 0.05). The success rate of biofeedback therapy was lower in the myelopathy group (28.6% for myelopathy vs. 62.0% for control group; p = 0.034). The response rate to biofeedback therapy was similar between radiculopathy and control group (62.5% for radiculopathy vs. 62.0% for control group; p = 1.000).

In constipation associated with mild myelopathy, delayed colonic transit and dyssynergic defecation were major pathophysiologic abnormalities and biofeedback was less effective compared with control group. However, in the radiculopathy group, biofeedback was as effective as in the control group.

Transanal irrigation for treatment of disordered defecation has been widely used among caregivers. Unique in its simplicity, reversible and minimally invasive, transanal irrigation has begun to find its place in the treatment hierarchy. Scheduled transanal irrigation aims to ensure emptying of the left colon and rectum. This prevents faecal leakage between washouts, providing a state of pseudocontinence, and re-establishes control over the time and place of defecation. Furthermore, regular evacuation of the rectosigmoid prevents constipation. The studies presented in this review represent the continuum of increasing evidence and knowledge of transanal irrigation for disordered defecation: from proof in principle through better knowledge of the physiology, towards establishing the indications and ensuring the safety of the treatment. Evidence of the superiority of transanal irrigation in spinal cord injury patients with neurogenic bowel dysfunction is provided, also from a health-economic perspective. Finally, a proposal is presented for an algorithm for the introduction of transanal irrigation for disordered defecation before irreversible surgery is considered.

The specific white matter location of all the spinal pathways conveying penile input to the rostral medulla is not known. Our previous studies using rats demonstrated the loss of low but not high threshold penile inputs to medullary reticular formation (MRF) neurons after acute and chronic dorsal column (DC) lesions of the T8 spinal cord and loss of all penile inputs after lesioning the dorsal three-fifths of the cord. In the present study, select T8 lesions were made and terminal electrophysiological recordings were performed 45-60 days later in a limited portion of the nucleus reticularis gigantocellularis (Gi) and Gi pars alpha. Lesions included subtotal dorsal hemisections that spared only the lateral half of the dorsal portion of the lateral funiculus on one side, dorsal and over-dorsal hemisections, and subtotal transections that spared predominantly just the ventromedial white matter. Electrophysiological data for 448 single unit recordings obtained from 32 urethane-anaesthetized rats, when analysed in groups based upon histological lesion reconstructions, revealed (1) ascending bilateral projections in the dorsal, dorsolateral and ventrolateral white matter of the spinal cord conveying information from the male external genitalia to MRF, and (2) ascending bilateral projections in the ventrolateral white matter conveying information from the pelvic visceral organs (bladder, descending colon, urethra) to MRF. Multiple spinal pathways from the penis to the MRF may correspond to different functions, including those processing affective/pleasure/motivational, nociception, and mating-specific (such as for erection and ejaculation) inputs.

Investigation of bowel function in 55 patients and 26 healthy volunteers using radiological, anorectal physiological and laser Doppler blood flow monitoring.

Bowel dysfunction is common after spinal cord injury (SCI). We aimed to determine whether hindgut testing of autonomic innervation provides insight into presence of symptoms, altered motor function (transit) and level of injury.

St Mark's Hospital, UK and The Spinal Injuries Unit, Royal National Orthopaedic Hospital, UK.

A total of 55 patients with chronic complete SCI and 26 healthy volunteers were studied. Twenty-four patients had lesions above T5 and 31 had lesions below T5. Thirty-five patients complained of constipation: 75% (18/24) of patients with lesions above T5 and 55% (17/31) of those with lesions below T5. Gut transit, rectal electrosensitivity and rectal blood flow were measured.

Slow gut transit occurred in 65% of patients and in all the 35 patients complaining of constipation. Delay was pancolonic. All patients had an elevated sensory threshold. The threshold was significantly higher in those with subjective constipation (P<0.01), slow transit (P<0.04) and high SCI (P=0.046). Mucosal blood flow was lower in SCI patients with constipation (P<0.04) and slow transit (P<0.03). It was higher than normal in high-SCI volunteers (P=0.056), reflecting loss of sympathetic inhibition.

In SCI, subjective constipation correlates closely with slow gut transit. Delay is pancolonic, regardless of the site of lesion. Sensory testing provides evidence for completeness of lesion, offering further evidence for pain transmission through sympathetic pathways. Studies in SCI patients provide further evidence of mucosal blood flow as a marker of altered autonomic innervation.

International expert working group.

To develop an International Bowel Function Extended Spinal Cord Injury (SCI) Data Set presenting a standardized format for the collection and reporting of an extended amount of information on bowel function.

Working group consisting of members appointed by the American Spinal Injury Association (ASIA) and the International Spinal Cord Society (ISCoS).

A draft prepared by the working group was reviewed by Executive Committee of the International SCI Standards and Data Sets and later by the ISCoS Scientific Committee and the ASIA Board. Relevant and interested scientific and professional organizations and societies (around 40) were also invited to review the data set and it was posted on the ISCoS and ASIA websites for 3 months to allow comments and suggestions. The ISCoS Scientific Committee, ISCoS Council and ASIA Board received the data set for final review and approval.

The International Bowel Function Basic SCI Data Set includes 26 items providing a thorough description of bowel-related symptoms as well as clinical assessment of anal sphincter function and description of total gastrointestinal or segmental colorectal transit times.

An International Bowel Function Extended SCI Data Set has been developed. This Data Set is mainly for research purposes and it should be used in combination with the information obtained from the International SCI Core Data Set and the International Bowel Function Basic SCI Data Set.

International expert working group.

To develop an International Bowel Function Basic Spinal Cord Injury (SCI) Data Set presenting a standardized format for the collection and reporting of a minimal amount of information on bowel function in daily practice or in research.

Working group consisting of members appointed by the American Spinal Injury Association (ASIA) and the International Spinal Cord Society (ISCoS).

A draft prepared by the working group was reviewed by Executive Committee of the International SCI Standards and Data Sets, and later by ISCoS Scientific Committee and the ASIA Board. Relevant and interested scientific and professional (international) organizations and societies (approximately 40) were also invited to review the data set and it was posted on the ISCoS and ASIA websites for 3 months to allow comments and suggestions. The ISCoS Scientific Committee, Council and ASIA Board received the data set for final review and approval.

The International Bowel Function Basic SCI Data Set includes the following 12 items: date of data collection, gastrointestinal or anal sphincter dysfunction unrelated to SCI, surgical procedures on the gastrointestinal tract, awareness of the need to defecate, defecation method and bowel care procedures, average time required for defecation, frequency of defecation, frequency of fecal incontinence, need to wear pad or plug, medication affecting bowel function/constipating agents, oral laxatives and perianal problems.

An International Bowel Function Basic SCI Data Set has been developed.

Faecal incontinence (FI) is a socially devastating problem. Sacral nerve modulation (SNM) has proven its place in the treatment of patients with FI. In this study, the first 100 definitive SNM implants in a single centre have been evaluated prospectively.

Patients treated between March 2000 and May 2005 were included. Faecal incontinence was defined as at least one episode of involuntary faecal loss per week confirmed by a 3-week bowel habit diary. Patients were eligible for implantation of a permanent SNM when showing at least a 50% reduction in incontinence episodes or days during ambulatory test stimulation. Preoperative workup consisted of an X-defaecography, pudendal nerve terminal motor latency measurement, endo-anal ultrasound and anal manometry. The follow-up visits for the permanent implanted patients were scheduled at 1, 3, 6 and 12 months and annually thereafter. The bowel habit diary and anal manometry were repeated postoperatively during the follow-up visits.

A total of 134 patients were included and received a subchronic test stimulation. One hundred patients (74.6%) had a positive test stimulation and received a definitive SNM implantation. The permanent implantation group consisted of 89 women and 11 men. The mean age was 55 years (range 26-75). The mean follow-up was 25.5 months (range 2.5-63.2). The mean number of incontinence episodes decreased significantly during the test stimulation (baseline, 31.3; test, 4.4; P < 0.0001) and at follow-up (36 months postoperatively, 4.8; P < 0.0001). There was no significant change in the mean anal resting pressure. The squeeze pressures were significantly higher at 6 months (109.8 mmHg; P = 0.03), 12 months (114.1 mmHg; P = 0.02) and 24 months postoperatively (113.5 mmHg; P = 0.007). The first sensation, urge and maximum tolerable volume did not change significantly. Twenty-one patients were considered late failures and received further treatment.

Sacral neuromodulation is an effective treatment for FI. The medium-term results were satisfying.

The study consisted of a clinical evaluation of bowel dysfunction and the relation with neurological patterns in spinal cord injury (SCI).

109 patients; 30% tetraplegics and 70% paraplegics; ASIA Impairment Scale: 65% A (complete), 12% B (sensitive incomplete), 11% C (motor incomplete with muscle grade <3), 13% D (motor incomplete with muscle grade >or= 3). 83% had spinal sacral reflexes (SSR). An interview and ano-rectal examination were performed.

77% patients required laxatives and 68% digital stimulation; 10% had bowel movements less than thrice a week and 18% spent more than one hour; 27% presented constipation, 31% fecal incontinence, 31% had ano-rectal pathology and 18% had autonomic dysreflexia (AD). Patients ASIA A,B,C with SSR took more suppositories, evacuated less frequently and spent more time than patients without SSR. Tetraplegics ASIA A,B,C had more constipation. Only patients with high level SCI and ASIA A,B,C with SSR had AD. ASIA D patients also needed laxatives, digital stimulation and presented colo-rectal symptoms.

The prevalence of colo-rectal symptoms is high in SCI patients and neurogenic bowel characteristics are related to neurological patterns.

For this study, a descriptive, explorative design was used.

As a result of spinal cord injury (SCI) patients may have a partial or complete loss of the sensations of defecation. To compensate this impairment, nurses initiate bowel management programs. Therefore, they need information about sensations of defecation. Accordingly, the research questions explore which sensations of defecation are reported by patients with SCI and whether they can be used to improve bowel care.

The Gemeinschaftskrankenhaus Herdecke and the Berufsgenossenschaftlichen Kliniken Bergmannsheil in Bochum, Germany.

A convenience sample of 27 patients with SCI was interviewed using a semistructured questionnaire. For data analysis, the frequency of the reported sensations was counted.

The results of the study show that the participants' defecation was indicated by abdominal sensations (n=20) or a prickling sensation (n=11) emerging mainly in the head. Additional signals comprised increased spasticity (n=10), cutis anserina (n=8) and sweating (n=6). Seventeen participants sensed actual defecation and 15 perceived its cessation. Six participants were able to initiate defecating according to their sensations.

The assessment of sensations of defecation in patients with SCI may indicate whether a bowel-management program with a consistent schedule for defecation is needed or if physiological defecation can be trained.

Abnormal bowel function is a key problem in patients with spinal cord injury (SCI). Previous works provided only partial information on colonic transit time (CTT) or anal dysfunction but did not identified a comprehensive neurogenic bowel pattern.

To evaluate clinical, neurological, and pathophysiological counterparts of neurogenic bowel in patients with motor complete SCI.

Fifty-four patients (56% men, mean age 35 yr) with chronic motor complete SCI (mean evolution time 6 yr) were evaluated: 41% with injuries above T7 (> T7) and 59% with injuries below T7 (< T7); patients were also classified according to the presence or not of sacral spinal reflexes. Clinical assessment, total and segmental CTT quantification, anorectal function evaluation by manometry, intrarectal balloon distension, and surface electromyography were performed.

Three different neuropathophysiological patterns were observed: Pattern A, present in > T7 injuries, characterized by very frequent constipation (86%) with significant defecatory difficulty and not very severe incontinence (Mean Wexner score 4.5); it was related to moderate delay in CTT (mainly in the left colon and recto-sigma), incapacity to increase the intra-abdominal pressure, and the absence of anal relaxation during the defecatory maneuvre; Pattern B, present in < T7 injuries with preserved sacral reflexes, characterized by not so frequent constipation (50%) but very significant defecatory difficulty and not very severe incontinence (Wexner 4.8); the pathophysiological counterpart was a moderate delay in CTT, capacity to increase intra-abdominal pressure, increased anal resistance during the defecatory maneuver, and presence of external anal sphincter (EAS) contraction when intra-abdominal pressure increased and during rectal distension; Pattern C, present in < T7 injuries without sacral reflexes, characterized by not very frequent constipation (56%) with less defecatory difficulty and greater severity of incontinence (Wexner 7.2); this was associated with severe delay in CTT (mainly in the left colon), capacity to increase intra-abdominal pressure, absence of anal resistance during the defecatory maneuver, and absence of EAS contraction when intra-abdominal pressure increased and during rectal distension.

In patients with motor complete SCI, we were able to define three different neuropathophysiological patterns that are associated with bowel function abnormalities and clinical complaints; this might be of help when designing therapeutic strategies.

Bowel dysfunction in patients with spinal cord injury often causes constipation, fecal incontinence, or a combination of both with a significant impact on quality of life. Transanal irrigation improves bowel function in selected patients. However, controlled trials of different bowel management regimens are lacking. The aim of the present study was to compare transanal irrigation with conservative bowel management (best supportive bowel care without irrigation).

In a prospective, randomized, controlled, multicenter trial involving 5 specialized European spinal cord injury centers, 87 patients with spinal cord injury with neurogenic bowel dysfunction were randomly assigned to either transanal irrigation (42 patients) or conservative bowel management (45 patients) for a 10-week trial period.

Comparing transanal irrigation with conservative bowel management at termination of the study, the mean (SD) scores were as follows: Cleveland Clinic constipation scoring system (range, 0-30, 30 = severe symptoms) was 10.3 (4.4) versus 13.2 (3.4) (P = .0016), St. Mark's fecal incontinence grading system (range, 0-24, 24 = severe symptoms) was 5.0 (4.6) versus 7.3 (4.0) (P = .015), and the Neurogenic Bowel Dysfunction Score (range, 0-47, 47 = severe symptoms) was 10.4 (6.8) versus 13.3 (6.4) (P = .048). The modified American Society of Colorectal Surgeon fecal incontinence scores (for each subscale, range is 0-4, 4 = high quality of life) were: lifestyle 3.0 (0.7) versus 2.8 (0.8) (P = .13), coping/behavior 2.8 (0.8) versus 2.4 (0.7) (P = .013), depression/self perception 3.0 (0.8) versus 2.7 (0.8) (P = .055), and embarrassment 3.2 (0.8) versus 2.8 (0.9) (P = .024).

Compared with conservative bowel management, transanal irrigation improves constipation, fecal incontinence, and symptom-related quality of life.

Rectal hyposensitivity (RH) relates to a diminished perception of rectal distension that is diagnosed during anorectal physiologic investigation. There have been few direct studies of this physiologic abnormality, and its contribution to the development of functional bowel disorders has been relatively neglected. However, it appears to be common in patients with such disorders, being most prevalent in patients with functional constipation with or without fecal incontinence. Indeed, it may be important in the etiology of symptoms in certain patients, given that it is the only "apparent" identifiable abnormality on physiologic testing. Currently, it is usually diagnosed on the basis of elevated sensory threshold volumes during balloon distension in clinical practice, although such a diagnosis may be susceptible to misinterpretation in the presence of altered rectal wall properties, and thus it is uncertain whether a diagnosis of RH reflects true impairment of afferent nerve function. Furthermore, the etiology of RH is unclear, although there is limited evidence to support the role of pelvic nerve injury and abnormal toilet behavior. The optimum treatment of patients with RH is yet to be established. The majority are managed symptomatically, although "sensory-retraining biofeedback" appears to be the most effective treatment, at least in the short term, and is associated with objective improvement in the rectal sensory function. Currently, fundamental questions relating to the contribution of this physiologic abnormality to the development of functional bowel disorders remain unanswered. Acknowledgment of the potential importance of RH is thus required by clinicians and researchers to determine its relevance.

Following spinal cord injury, colorectal problems are a significant cause of morbidity, and chronic gastrointestinal problems remain common with increasing time after injury. Although many cord-injured patients achieve an adequate bowel frequency with drugs and manual stimulation, the risk and occurrence of fecal incontinence, difficulties with evacuation, and need for assistance remain significant problems. The underlying physiology of colorectal motility and defecation is reviewed, and consequences of spinal cord injury on defecation are reported. A discussion of present management techniques is undertaken and new directions in management and research are suggested. There is need for more intervention in regard to bowel function that could improve quality of life, but there is also a need for more research in this area.

The impact of spinal cord injury on an individual's gastrointestinal tract function is often poorly understood by the general public and also by those involved with persons with spinal cord injury. This chapter reviews the anatomy, physiology and function of the gastrointestinal tract, with particular emphasis on neurological control mechanisms. In turn, it relates the effect that spinal cord injury has on the neurological control of the gastrointestinal tract. The symptoms that are encountered by patients in the acute phase following injury, and by individuals in the months/years after injury, with particular reference to the effect of altered autonomic nervous system control of the gastrointestinal tract, are discussed. Together with a following summary of current bowel management regimens and techniques, this chapter aims to provide an overall view of the effect that autonomic dysfunction due to spinal cord injury has on gastrointestinal function.

This chapter describes the results of investigations of the upper and lower gastrointestinal tract in subjects with complete and incomplete spinal cord injury. In one study, gastric emptying was investigated and found delayed. The delay was tentatively attributed to a colo-gastric inhibitory reflex triggered by inappropriate colonic emptying. In another study, anorectal motor and sensory functions were measured. Decreased tone of the internal anal sphincter, exaggerated recto-anal reflexes following rectal distension and spontaneous high-amplitude rectal contractions at low distension volumes were among the findings of the study. Some of the subjects, classified as having a complete injury according to usual clinical criteria (American Spinal Injury Association, ASIA), reported sensation of distension of the rectum. This raises the issue of the need for better methods for the clinical assessment of sensory transmission in the spinal cord. Promising results obtained with functional magnetic resonance imaging of the brain during rectal stimulation in a small group of paraplegics, with complete injuries by ASIA criteria, showed evidence of activation of several brain regions.

Previous surveys of gastrointestinal symptoms after spinal cord injury have not used validated questionnaires and have not focused on the full spectrum of such symptoms and their relationship to factors, such as level of spinal cord injury and psychologic dysfunction. This study was designed to detail the spectrum and prevalence of gastrointestinal symptoms in spinal cord injury and to determine clinical and psychologic factors associated with such symptoms.

Established spinal cord injury patients (>12 months) randomly selected from a spinal cord injury database completed the following three questionnaires: 1) Rome II Integrative Questionnaire, 2) Hospital Anxiety and Depression Scale, and 3) Burwood Bowel Dysfunction after spinal cord injury.

A total of 110 patients participated. The prevalence of abdominal bloating and constipation were 22 and 46 percent, respectively. Bloating was associated with cervical (odds ratio = 9.5) and lumbar (odds ratio = 12.1) level but not with thoracic level of injury. Constipation was associated with a higher level of injury (cervical odds ratio = 5.6 vs. lumbar) but not with psychologic factors. In contrast, abdominal pain (33 percent) and fecal incontinence (41 percent) were associated with higher levels of anxiety (odds ratio = 6.8, and odds ratio = 2.4) but not with the level of injury.

There is a high prevalence and wide spectrum of gastrointestinal symptoms in spinal cord injury. Abdominal bloating and constipation are primarily related to specific spinal cord levels of injury, whereas abdominal pain and fecal incontinence are primarily associated with higher levels of anxiety. Based on our findings, further physiologic and psychologic research studies in spinal cord injury patients should lead to more rational management strategies for the common gastrointestinal symptoms in spinal cord injury.

The inability to control bowel discharge is not only common but extremely distressing. It has a negative impact on a patient's lifestyle, leads to a loss of self-esteem, social isolation and a diminished quality of life. Faecal incontinence is often due to multiple pathogenic mechanisms and rarely due to a single factor. Normal continence to stool is maintained by the structural and functional integrity of the anorectal unit. Consequently, disruption of the normal anatomy or physiology of the anorectal unit leads to faecal incontinence. Currently, several diagnostic tests are available that can provide an insight regarding the pathophysiology of faecal incontinence and thereby guide management. The treatment of faecal incontinence includes medical, surgical or behavioural approaches. Today, by using logical approach to management, it is possible to improve symptoms and bowel function in many of these patients.

Electrophysiological and physiological studies have suggested that the ventral medullary gigantocellular reticular nuclei (composed of the gigantocellular ventralis and pars alpha nuclei as well as the adjacent lateral paragigantocellular nucleus; abbreviated Gi-LPGi complex) provide descending control of pelvic floor organs (Mackel [1979] J. Physiol. (Lond.) 294:105-122; Hubscher and Johnson [1996] J. Neurophysiol. 76:2474-2482; Hubscher and Johnson [1999] J. Neurophysiol. 82:1381-1389; Johnson and Hubscher [1998] Neuroreport 9:341-345). Specifically, this complex of paramedian reticular nuclei has been implicated in the inhibition of sexual reflexes. In the present study, an anterograde fluorescent tracer was used to investigate direct descending projections from the Gi-LPGi complex to retrogradely labeled pudendal motoneurons (MN) in the male rat. Our results demonstrated that, although a high density of arborizations from Gi-LPGi fibers appears to be in close apposition to pudendal MNs, this relationship also applies to other MNs throughout the entire spinal cord. The Gi-LPGi also projects to spinal autonomic regions, i.e., both the intermediolateral cell column and the sacral parasympathetic nucleus, as well as to regions of the intermediate gray, which contain interneurons involved in the organization of pelvic floor reflexes. Lastly, throughout the length of the spinal cord, numerous neurons located primarily in laminae VII-X, were retrogradely labeled with Fluoro-Ruby after injections into the Gi-LPGi. The diffuse descending projections and arborizations of this pathway throughout the spinal cord suggest that this brainstem area is involved in the direct, descending control of a variety of spinal activities. These results are in contrast with our observations of the discrete projections of the caudal nucleus raphe obscurus, which target the autonomic and somatic MNs involved specifically in sexual and eliminative functions (Hermann et al. [1998] J. Comp. Neurol. 397:458-474).

Parasympathetic afferent nerves are thought to mediate rectal filling sensations. The role of sympathetic afferent nerves in the mediation of these sensations is unclear. Sympathetic nerves have been reported to mediate nonspecific sensations in the pelvis or lower abdomen in patients with blocked parasympathetic afferent supply. It has been reported that the parasympathetic afferent nerves are stimulated by both slow ramp (cumulative) and fast phasic (intermittent) distention of the rectum, whereas the sympathetic afferent nerves are only stimulated by fast phasic distention. Therefore, it might be useful to use the two distention protocols to differentiate between a parasympathetic and sympathetic afferent deficit.

Sixty control subjects (9 males; median age, 48 (range, 20-70) years) and 100 female patients (median age, 50 (range, 18-75) years) with obstructed defecation entered the study. Rectal sensory perception was assessed with an "infinitely" compliant polyethylene bag and a computer-controlled air-injection system. This bag was inserted into the rectum and inflated with air to selected pressure levels according to two different distention protocols (fast phasic and slow ramp). The distending pressures needed to evoke rectal filling sensations, first sensation of content in the rectum, and earliest urge to defecate were noted, as was the maximum tolerable volume.

In all control subjects, rectal filling sensations could be evoked. Twenty-one patients (21 percent) experienced no sensation at all in the pressure range between 0 and 65 mmHg during either slow ramp or fast phasic distention. The pressure thresholds for first sensation, earliest urge to defecate, and maximum tolerable volume were significantly higher in patients with obstructed defecation (P < 0.001). In each subject, the pressure thresholds for first sensation, earliest urge to defecate, and maximum tolerable volume were always the same, regardless of the type of distention.

Rectal sensory perception is blunted or absent in the majority of patients with obstructed defecation. The observation that this abnormality can be detected by both distention protocols suggests that the parasympathetic afferent nerves are deficient. Because none of the patients experienced a nonspecific sensation in the pelvis or lower abdomen during fast phasic distention, it might be suggested that the sympathetic afferents are also deficient. This finding implies that it is not worthwhile to use different distention protocols in patients with obstructed defecation.

Patients with spinal cord lesion suffer from complex disorders of bladder and anorectal function. We assessed the value of urodynamics and anorectal manometry as prognostic and diagnostic tools in these patients and evaluated the usefulness of these techniques for the differentiation between complete and incomplete spinal cord lesions. Thirty patients with suprasacral spinal cord injury (six women, 24 men; mean age, 31 years) underwent anorectal manometry and urodynamics within the first 40 days after injury. The findings were compared to the results of a clinical neurologic evaluation. Fifteen patients were classified as complete lesions on their clinical signs, three of these lesions were incomplete according to urodynamic testing and five were incomplete according to visceral sensory testing by anorectal manometry. Despite significant differences in maximum bladder capacity (589 versus 465 mL), maximum detrusor pressure (18 versus 31 cm H2O) was not significantly different between patients with complete and patients with incomplete spinal cord injury. Anorectal manometry did not reveal any significant differences in resting pressure, abdominal pressure, and maximal rectum volume between these groups. Urodynamics and anorectal manometry may be superior to neurologic assessment of completeness of spinal cord lesions. Urodynamics and anorectal manometry were not helpful in the prediction of onset or severity of detrusor hyperreflexia. Thus, we do not regard anorectal manometry as a standard diagnostic tool in spinal cord injury patients.

Bowel dysfunction is common in patients with spinal cord lesions. This study aims to determine whether there are any discriminatory findings at anorectal physiologic testing in patients with spinal cord lesions.

Twelve consecutive patients (6 females) with significant spinal cord lesions who had mixed symptoms of constipation, fecal impaction, and fecal incontinence were evaluated by perfusion manometry and pudendal nerve terminal motor latency. None of the patients had a sphincter defect as evaluated by endoanal ultrasonography.

The median age was 54 (range, 40-87) years. Eight (67 percent) of them had had traumatic spinal cord injuries. Other spinal cord lesions included spina bifida, syringomyelia, arachnoid cyst, and spinal cord ischemia after abdominal aortic aneurysm repair. In patients with spinal cord lesions, the mean (range) resting anal canal pressure and maximum squeeze anal canal pressure were 46 (10-100) mmHg and 76 (30-120) mmHg respectively compared with 62 (50-70) mmHg, and 138 (100-180) mmHg, respectively, in healthy controls. Eleven (92 percent) patients had prolonged pudendal nerve terminal motor latency (9 bilateral and 2 unilateral) whereas rectoanal inhibitory reflex was abolished in all 9 patients tested.

Spinal patients with severe bowel symptoms tended to have lower anal canal pressures than healthy controls. Pudendal netropathy and impaired rectoanal inhibitory reflex are common and may be important in the pathogenesis of bowel dysfunction in patients with spinal cord lesions.

In functional disorders it is unknown whether disturbed function is due to an intrinsic gut abnormality or altered extrinsic innervation.

To study whether measurement of mucosal blood flow could be used as a quantitative direct measure of gut extrinsic nerve autonomic activity in patients with idiopathic constipation.

Seventy two patients with idiopathic constipation and 26 healthy volunteers had rectal mucosal blood flow measurements by a laser Doppler flowmetry probe applied 10 cm from the anus. Measurements were made at rest and after inhaled placebo and ipratropium 40 microg.

Constipated subjects had lower baseline rectal blood flow than controls. Patients with slow transit had lower mucosal blood flow than normal transit. The number of retained markers on x-ray was inversely correlated with blood flow. Ipratropium reduced blood flow compared with placebo, reduced it less in constipated patients than controls, and reduced it less in patients with slow compared with normal transit. Constipated patients, not controls, showed a significantly attenuated RR interval (the interval between successive R waves on the ECG) variability, and blood flow correlated with vagal function.

Laser Doppler mucosal flowmetry is a gut specific, quantitative measure of extrinsic autonomic nerve activity. The technique has shown that patients with idiopathic constipation have impaired extrinsic gut nerve activity, and this is more notable in those with slow transit. The degree of slow transit correlates with the degree of impaired extrinsic innervation.

Acute hyperglycaemia affects the perception of sensations arising from the gastrointestinal tract. The mechanisms responsible for this effect are unknown. Recordings of cerebral evoked potentials (EPs) can be used to assess the integrity of visceral afferent pathways. Our aim was to determine whether hyperglycaemia affects EPs elicited by rectal distension in healthy humans.

Twelve healthy men, aged 19-31 years, were studied. A manometric catheter, incorporating a rectal balloon, was positioned 7-10 cm from the anal verge. Balloon distensions at both 'low' ( approximately 20 mL) and 'high' ( approximately 28 mL) volumes were performed, in a single-blind, randomized order, during both euglycaemia (4 mmol L-1) and hyperglycaemia (12 mmol L-1). EPs were recorded from a midline scalp electrode (Cz, International 10-20 system) and averaged for each series of 50 distensions. EP latencies and interpeak amplitudes were calculated.

Polyphasic EPs were recorded in all but one subject. Although the blood glucose concentration had no significant effect on the latencies of the EP peaks elicited by either 'low'- or 'high'-volume balloon distension, the interpeak amplitude (P1-N1) was greater during hyperglycaemia than during euglycaemia at the 'low' balloon volume (6.3 +/- 1.2 microV vs. 4.8 +/- 1.0 microV, P < 0.05). The blood glucose concentration had no significant effect on the perception of rectal balloon distension.

We conclude that in normal subjects acute hyperglycaemia increases the amplitude of the cerebral EP elicited by rectal balloon distension at low balloon volumes, suggesting that the effects of hyperglycaemia on gastrointestinal sensation may be mediated by central mechanisms.

Perception of, and adaptation of the rectum to, distension probably play an important role in the maintenance of continence, but perception studies in faecal incontinence provide controversial conclusions possibly related to methodological biases. In order to better understand perception disorders, the aim of this study was to analyse anorectal adaptation to rectal isobaric distension in subjects with incontinence.

Between June 95 and December 97, 97 consecutive patients (nine men and 88 women, mean (SEM) age 55 (1) years) suffering from incontinence were evaluated and compared with 15 healthy volunteers (four men and 11 women, mean age 48 (3) years). The patients were classified into three groups according to their perception status to rectal isobaric distensions (impaired, 22; normal, 61; enhanced, 14). Anal and rectal adaptations to increasing rectal pressure were analysed using a model of rectal isobaric distension.

The four groups did not differ with respect to age, parity, or sex ratio. Magnitude of incontinence, prevalence of pelvic disorders, and sphincter defects were similar in the incontinent groups. When compared with healthy controls, anal pressure and rectal adaptation to distension were decreased in incontinent patients. When compared with incontinent patients with normal perception, patients with enhanced perception experienced similar rectal adaptation but had reduced anal pressure. In contrast, patients with impaired perception showed considerably decreased rectal adaptation but had similar anal pressure.

Abnormal sensations during rectal distension are observed in one third of subjects suffering from incontinence. These abnormalities may reflect hyperreactivity or neuropathological damage of the rectal wall.

We wished to establish anorectal functions in patients with spinal cord lesions, related to the level of lesion and its completeness. We also wished to determine the value of neurophysiological tests for completeness of transsections in comparison with manometry and visceral sensory testing. In 32 patients (31.5 +/- 14.1 years, 25 males) with spinal trauma, completeness of transsection was assessed clinically. In 16 of these patients (30 +/- 15.6 years, nine males), a neurological work-up included recording of somatosensory evoked potentials (SEP) and motor evoked potentials (MEP) from the pudendal nerve within the first week after trauma. Also, anal sphincter EMG and pudendal nerve terminal motor latency (PNTML) were assessed. All patients also underwent conventional anorectal manometry and visceral sensory testing. Of all 32 patients, 15 were judged as 'complete' based on their clinical signs. Of those 16 tested neurologically, seven were labelled 'complete' since no MEP or SEP were detectable; one had pudendal SEP and MEP present, while SEP were present but delayed (47.0 +/- 8.8 msec) in the remaining patients. In four of these patients, also MEP were recorded (27.9 +/- 5.2 msec) and normal. PNTML was present in 12/16 patients independent of the completeness of lesion, and was rated normal in nine and delayed in three patients. EMG was normal in five, and pathological in 11 cases. In 5/15 cases of those judged as 'complete' (in 3/7 evaluated neurologically), visceral sensory testing revealed a minimal threshold for rectal perception of distension of 44 mL (range: 10-130), which sometimes was also perceived as urge to defecate. In a further case, manometry showed major voluntary action of the anal sphincter. These patients had lesions at all levels of the spinal column, ranging from cervical (C4,C6,C7) via thoratical (2 x T7,T8,T12) to lumbar segments. Anorectal function testing, and specifically visceral sensory testing may be superior to neurological assessment of 'completeness' of spinal cord lesions. It may be that visceral afferent pathways others than spinothalamic tract are involved in rectal perception that are less accessible to conventional neurophysiological diagnostic work-up.

Sacral reflexes consist of motor responses in the pelvic floor and sphincter muscles evoked by stimulation of sensory receptors in pelvic skin, anus, rectum, or pelvic viscera. These responses may be elicited by physical or electrical stimuli. They have been used in research studies of the pathophysiology of pelvic floor and anorectal disorders and many have been recommended for diagnostic use. These reflexes are described and discussed in this review. More rigorous evaluation of their value in the clinical assessment and care of patients with pelvic floor and sphincter disorders is required. Currently direct comparisons of the value of particular responses are generally not available, and few of these reflexes have proven validity for use in clinical diagnosis.