Clinical effects of childbirth with median episiotomy and anal sphincter injury on fecal incontinence of primiparous women

Obstetric damage of the anorectal continence organ can lead to impaired anal continence. To assess the effect of birth, either with or without direct injury of the anal sphincter, 123 primiparae were studied. 41 patients with a midline episiotomy and 82 patients with an additional injury of the anal sphincter were assessed at a median of 21 weeks postpartum and compared with 18 healthy volunteers. Anorectal manometry as well as a standardized questionnaire were employed. Patients with an additional injury of the anal sphincter reported persistent flatus incontinence significantly more often (p = 0.0069) than patients with a midline episiotomy only. Incontinence of solid or liquid stool occurred only transiently. Compared to nulliparae in all primiparae a significant shortening of anal canal and a decreased squeeze pressure were observed. In addition, a significantly reduced resting pressure was seen in patients with an anal sphincter injury. The rectoanal inhibitory reflex was absent significantly more often following anal sphincter tear (p = 0.0023). Vaginal delivery, both with and without anal sphincter injury, leads to early detectable changes in anorectal sphincter function.     

Functional results following the antegrade continence enema procedure

BACKGROUND: Forty children who underwent the antegrade continence enema (ACE) procedure for faecal soiling were studied to determine factors predictive of outcome. METHODS: There were four patient groups: (1) ambulant with spinal dysraphism (n = 13), (2) wheelchair bound with spinal dysraphism (n = 14), (3) ambulant with miscellaneous disorders (n = 11) and (4) wheelchair bound with miscellaneous disorders (n = 2). Effectiveness of the procedure was assessed using technical evaluation and quality-of-life improvement (QOLI) scores (0-5). Objective assessment included colonic transit time (CTT) and anorectal manometry. Median follow-up was 21 (range 5-37) months. RESULTS: Some 28 of 40 children achieved continence. The procedure was reversed in four of 40 children. Of the other 36 children with a functioning ACE stoma, all reported improvement in quality of life (mean QOLI score 3.5). There were no significant differences in technical evaluation score, QOLI score, CTT, manometry findings or continence between ambulant groups and the wheelchair-bound group with miscellaneous disorders. QOLI score, anorectal squeeze pressure and continence were significantly poorer in those who were wheelchair bound with spinal dysraphism. Absent squeeze pressure was associated with poor outcome. CONCLUSION: Wheelchair-bound children with spinal neuropathy have a poorer outcome following the ACE procedure. Although ACE is an effective method of promoting faecal continence, it is essential to determine the aetiology of incontinence and sphincter function before operation.     

Third-degree obstetric perineal tear: long-term clinical and functional results after primary repair

BACKGROUND: This study was designed to investigate the long-term clinical and anorectal functional results after primary repair of a third-degree obstetrical perineal rupture. METHODS: One hundred and fifty-six consecutive women who had a primary repair of a third-degree perineal rupture were sent a questionnaire and asked to undergo anorectal function testing (anal manometry, anorectal sensitivity, anal endosonography and pudendal nerve terminal motor latency (PNTML)) RESULTS: Some 117 women (75 per cent) responded. Anal incontinence was present in 47 women (40 per cent); however, in most cases only mild symptoms were present. In 40 women additional anorectal function tests were performed and compared with findings in normal controls. Mean(s.d.) maximum squeeze pressure (31(15) versus 63(17) mmHg, P< 0.001) was decreased and first sensation to filling of the rectum (88(47) versus 66(33) ml, P=0.03) and anal mucosal electrosensitivity (4.7(1.7) versus 2.5(0.8) mA, P=0.003) were increased compared with values in normal controls. In 35 women (88 per cent) a sphincter defect was found with anal endosonography. Factors related to anal incontinence were the presence of a combined anal sphincter defect (relative risk (RR) 1.7 (95 per cent confidence interval (c.i.) 1.1-2.8)) or subsequent vaginal delivery (RR 1.6 (95 per cent c.i. 1.1-2.5)). CONCLUSION: Anal incontinence prevails in 40 per cent of women 5 years after primary repair of a third-degree perineal rupture. The presence of a combined sphincter defect or subsequent vaginal delivery increase the risk of anal incontinence.     

Prevalence and determinants of carotid atherosclerosis in healthy postmenopausal women

Fecal incontinence is an under-reported complication of scleroderma. Ten incontinent patients with scleroderma were evaluated through anorectal manometry and compared with 20 incontinent patients without scleroderma who were matched for age and sex as controls. The scleroderma patients had a higher voluntary external anal squeeze pressure, whereas the resting internal anal sphincter pressure was similar to that of the control group. The threshold for rectal sensation in the scleroderma group was significantly less than that in controls. Episodes of fecal incontinence, anal canal length, and maximal tolerable volume were not significantly different between the study groups. The rectoanal inhibitory response was abnormal in 80% of patients with systemic sclerosis but was normal in 70% of the controls. Stool consistency was significantly looser in the scleroderma patients. Treatment of fecal incontinence in scleroderma patients may be successful in many patients using a combination of dietary and pharmacologic manipulation because diarrhea is an important etiologic cofactor superimposed on reduced internal anal sphincter pressure.     

Diagnosing anal sphincter injury with transanal ultrasound and manometry

PURPOSE: This study was undertaken to evaluate how well anorectal manometry and transanal ultrasonography diagnose anal sphincter injury. METHODS: Anorectal manometry and transanal ultrasonography were performed in 20 asymptomatic nulliparous women and 20 asymptomatic parous women, and the results were compared with those obtained in 31 incontinent women who subsequently underwent sphincteroplasty and, thus, had operatively verified anal sphincter injury. By using computerized manometry analysis, mean maximum resting and squeeze pressures, sphincter length, and vector symmetry were determined in all women. All transanal ultrasounds were interpreted blinded as to the patient's history, physical examination, and manometry results. RESULTS: Manometric resting and squeeze pressures were significantly higher in the asymptomatic nulliparous women than in the asymptomatic parous women, and both groups had significantly higher pressures than the incontinent women (P < 0.001). Anal sphincter length and vector symmetry index were significantly decreased in incontinent women compared with asymptomatic women (P < 0.01). Decreased resting and squeeze pressures suggestive of possible sphincter injury were found in 90 percent of incontinent women with known anal sphincter injury. Decreased anal sphincter length and vector symmetry were found in only 42 percent of women with known anal sphincter injury. Transanal ultrasound was able to identify 100 percent of the known sphincter injuries but also falsely diagnosed injury in 10 percent of the asymptomatic nulliparous women with intact anal sphincters. False identification of sphincter injury increased when transanal ultrasound scanning was performed proximal to the distal 1.5 cm of the anal canal. CONCLUSION: Although nonspecific, decreased resting and squeeze pressures were found in 90 percent of patients with anal sphincter injury. Decreased anal sphincter length or vector symmetry index were present in only 42 percent of patients with known sphincter injury. When limited to the distal 1.5 cm of the anal canal, transanal ultrasound identified all known sphincter injuries but falsely identified injury in 10 percent of women with intact anal sphincters. Transanal ultrasound in combination with decreased anal pressures correctly identified all intact sphincters and 90 percent of known anal sphincter injuries.     

Technic of overlapping sphincter anal repair in the treatment of traumatic anal incontinence

Faecal incontinence is an important disabling symptom in the affected patients. Classically, we divide faecal incontinence in two main types: neurogenic faecal incontinence and traumatic anal incontinence. Traumatic anal incontinence is due to causes damaging sphincteric mechanism directly. The aim of the present study was to evaluate the outcome of overlapping sphincter anal repair procedure in the management of traumatic anal incontinence. To this end we studied 27 patients with traumatic anal incontinence who underwent an overlapping sphincter anal repair procedure according to the method described by Parks and McPartlin in 1971. Mean follow up was up three years and was based mainly both on clinical evaluation with anorectal exploration and manometric values carried out on a 6 monthly basis. When the outcome was evaluated in terms of faecal continence our date were similar to those reported by Parks and Fang. In the subjects studied we haven't reported any major complications apart from one case of abscess, one case of wound's infection and one case of stenosis which were efficaciously treated. Our findings supported the view that overlapping sphincter anal repair procedure is the surgical approach of choice in the patients with traumatic anal incontinence.     

Metabolism of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in isolated rat lung and liver

PURPOSE: Assessment of sustained voluntary contraction of the external sphincter is helpful in evaluating the patient who has a defecation disorder on presentation. A new index of external sphincter function is described. METHOD: A prospective registry of patients referred for computerized anal manometry using standard protocols was reviewed. Patients were grouped by primary symptoms; those with overlapping complaints were excluded. The rate of fatigue, defined as the change in stationary squeeze over a 40-second period of voluntary contraction, was calculated by linear regression analysis. Fatigue rate index, a calculated measure of time necessary for the external sphincter to become completely fatigued, was determined to permit comparison of external sphincter fatigue in patients with different complaints. RESULTS: Twenty-six healthy volunteers (15 women; mean age, 45 years), 33 patients with a primary complaint of anal seepage (13 women; mean age, 53 years), 75 patients with gross incontinence (61 women; mean age, 53 years), and 49 patients with severe constipation (41 women; mean age, 45 years) were evaluated. Mean resting and squeeze pressures were 55 mmHg and 107 mmHg for volunteers, 37 mmHg and 97 mmHg for patients with seepage, 30 mmHg and 49 mmHg for incontinent patients, and 56 mmHg and 93 mmHg for constipated patients. Pudendal neuropathy, as evidenced by a prolonged pudendal nerve terminal motor latency (> 2.4 ms), was identified in 13 percent of volunteers, 32 percent of patients with seepage, 54 percent of incontinent patients, and 38 percent of constipated patients. Mean fatigue rate index was 3.3 minutes for volunteers, 2.3 minutes for seepage patients, 1.5 minutes for incontinent patients, and 2.8 minutes for constipated patients. Compared with volunteers and patients with seepage, the incontinent patients had a significantly shorter fatigue rate index (P < 0.05; Student's t-test), which was independent of the variations in resting pressure (P < 0.05; two-way analysis of variance). CONCLUSION: The external anal sphincter is normally subject to fatigue. Patients with worsening degrees of incontinence have a predictably lower fatigue rate index. Fatigue rate index is a simple measure of external sphincter integrity, which may be used in assessment of sphincter function and future treatment protocols.     

Gluteus maximus augmentation for the treatment of fecal incontinence

Fecal incontinence is a devastating problem for school-aged children and adults. Medical and biofeedback therapies are unsuccessful in most patients who have severely defective internal and external sphincters. Continued fecal incontinence frequently leads to social isolation and withdrawal. Gluteus maximus augmentation of the sphincter mechanism is one surgical method for treating fecal incontinence. The authors present their results with gluteus maximus augmentation of the anal sphincter and describe patient selection criteria. From 1992 through 1996, seven patients underwent gluteus maximus augmentation of the anal sphincter for fecal incontinence. Six of these patients were children 5 to 6 years of age who had major deficiencies of their anorectal sphincter demonstrated by manometry. One patient was a 56-year-old adult woman who had acquired idiopathic fecal incontinence. Four of the six children (67%) had imperforate anus and two had cloacal anomalies (33%). The augmentation was performed in three stages. A sigmoid-end colostomy with a Hartman's pouch was followed 1 month later by rotation of a portion of the gluteus maximus for anorectal sphincter augmentation. A colostomy take down was performed 2 to 4 months later. All patients underwent dilatation after sphincter augmentation and were taught muscle exercises for using their neosphincter during the period before colostomy take down. Four of six children and the adult are continent postoperatively (71%). Both patients who remain incontinent are unable to sense rectal distention clinically or on anal manometric analysis but have excellent voluntary sphincter tone. Fecal incontinence can be successfully treated with gluteus maximus augmentation in carefully selected patients. Patients unable to sense rectal distension are unlikely to benefit from this procedure. The presence of a rectal reservoir and a skin-lined anal canal also appear to be important in attaining fecal continence.     

Glutaraldehyde cross-linked collagen in the treatment of faecal incontinence

BACKGROUND: The treatment of faecal incontinence secondary to internal anal sphincter dysfunction is unsatisfactory. The aim of the study was to evaluate the efficacy of anal glutaraldehyde cross-linked (GAX) collagen injections in patients with a surgically incorrectable disorder. METHODS: Seventeen patients were studied: nine had idiopathic faecal incontinence, three had incontinence following haemorrhoidectomy, two following internal sphincterotomy, two following an internal sphincter defect from obstetric injury and one following treatment for fistula in ano. All patients were refractory to conservative treatment and were unsuitable for surgical repair. All had anorectal physiology and endoanal ultrasonography before and after GAX collagen injections. RESULTS: All patients tolerated the injection without side-effects. All patients had an intact external anal sphincter. Following injection, 11 patients showed marked symptomatic improvement. One patient reported symptomatic improvement but remained in clinical grade 3, and two reported minimal improvement. There was no improvement in three patients, but one of these had a repeat injection and showed significant improvement subsequently. CONCLUSION: Injection of GAX collagen in the anal canal is a simple and well tolerated method of treating faecal incontinence due to internal sphincter dysfunction. Early results suggest it provides an easy and reliable alternative to the currently available methods that are often unsuccessful and at best unpredictable.     

A retrospective study of the effects of pelvic irradiation for gynecological cancer on anorectal function

PURPOSE: To evaluate the prevalence of anorectal dysfunction following therapeutic pelvic irradiation. METHODS AND MATERIALS: Anorectal function was evaluated in 15 randomly selected patients (aged 47-84 years) who had received pelvic irradiation for treatment of carcinoma of the uterine body and cervix 5 and 10 years earlier. The following parameters were assessed in each patient: (a) anorectal symptoms (questionnaire), (b) anorectal pressures at rest and in response to rectal distension, voluntary squeeze, and increases in intraabdominal pressure (multiport anorectal manometry with concurrent electromyography of the anal sphincters), (c) rectal sensation (rectal balloon distension) and, (d) anal sphincteric morphology (ultrasound). Results were compared with those obtained in nine female control subjects. RESULTS: Ten of the 15 patients had urgency of defecation and 4 also suffered fecal incontinence. Basal anorectal pressures measured just proximal to the anal canal (p = 0.05) and anorectal pressures generated in response to voluntary squeeze measured at the anal canal were less (p < 0.01) in the patients. The fall in anal pressures in response to rectal distension was greater in the patients (p < 0.05) and the desire to defecate occurred at lower rectal volumes (p < 0.05). The slope of the pressure/volume relationship in response to rectal distension was greater (p < 0.05) in the patients, suggestive of a reduction in rectal compliance. In 14 of the 15 patients at least one parameter of anorectal motor function was outside the control range. There was no difference in the thickness of the anal sphincters between the two groups. CONCLUSION: Abnormal anorectal function occurs frequently following pelvic irradiation for gynecological malignant diseases and is characterized by multiple dysfunctions including weakness of the external anal sphincter, stiffness of the rectal wall, and a consequent increase in rectal sensitivity.     

Clonazepam in the treatment of panic disorder: a double-blind, placebo-controlled trial investigating the correlation between clonazepam concentrations in plasma and clinical response

The aim of this study was to investigate the possibility of neuromuscular dysfunction in patients with faecal incontinence by measuring interference patterns in the external anal sphincter and puborectalis muscles with quantitative electromyography. The design was an open study including 20 patients with faecal incontinence; in 14 the aetiology was idiopathic and 6 had rupture of the external anal sphincter. Electromyographic interference patterns (turns/amplitude analysis) measured at rest and during maximum voluntary contraction in all patients were recorded together with fibre density measured by single fibre electromyography (n = 10) and anal pressure measured at rest and at maximum contraction (n = 17). A comparison was made with results of a previously published series of reference values taken from normal volunteers. The density of the interference pattern on maximum contraction of the puborectalis muscle was significantly lower among the patients with idiopathic faecal incontinence than among the reference group (137 compared with 241 turns/second, p < 0.01). There was also a significant difference on maximum contraction of the anal sphincter muscle among the group in whom it was ruptured compared with the reference group (76 compared with 165 turns/second, p < 0.05). Fibre density increased with age and was significantly higher among those with idiopathic incontinence (1.64 (0.2) compared with 1.33 (0.1) in the reference group, p < 0.01). There were no significant differences in anal manometry measurements between the groups. In conclusion, in patients with faecal incontinence the role of central activation of the perineal muscles is important, though other factors may play a part.     

Improve the quality of vaginal delivery]

Between 1990 and 1992, external sphincter repair was performed in 20 patients rendered faecally incontinent after earlier fistula surgery. All were improved, 13 (65%) achieving Grade 1 or 2 continence. Postoperative ultrasound was useful in explaining the sub-optimal outcome of 3 patients who still had defects. Clinical outcome in female patients was better than in male patients. Clinical outcome was not related to the results of preoperative manometry, the site of external sphincter damage, the use of a stoma, or the occurrence of wound complications. External sphincter repair for faecal incontinence after fistula surgery achieves good results in the majority of patients.     

HLA-DRB1 alleles and beta 2 glycoprotein I-dependent anticardiolipin antibodies in Japanese patients with systemic lupus erythematosus

PURPOSE: This study was designed to evaluate the anatomic and functional consequences of lateral internal sphincterotomy in patients who developed anal incontinence and in matched controls. METHODS: The study includes 13 patients with anal incontinence after lateral internal sphincterotomy and 13 controls who underwent the same operation and were continent and satisfied with the results of the procedure. Patients underwent clinical evaluation, anorectal manometry, pudendal nerve terminal motor latency testing, and endoanal ultrasonography. RESULTS: Sphincterotomies were longer in incontinent patients (75 vs. 57 percent), but the resting pressure and length of the high-pressure zone were not different between groups. Surprisingly, maximum voluntary contraction was higher in incontinent patients than in continent controls (136 vs. 100 mmHg). Rectal sensation and pudendal nerve terminal motor latency were similar in both groups. The defect in the internal sphincter was wider in incontinent patients than in continent controls (17.3 vs. 14.4 mm), but these differences were not statistically significant. The thickness of the internal sphincter measured by endoanal ultrasound was identical in both groups, but the external sphincter was thinner in incontinent patients both at the site of the sphincterotomy (6.8 vs. 8.1 mm) and in the posterior midline (7.1 vs. 8.6 mm). CONCLUSIONS: Anal incontinence after lateral internal sphincterotomy is directly related to the length of the sphincterotomy. Whether secondary to preoperative sphincter abnormality or the result of lateral internal sphincterotomy, the external sphincter is thinner in incontinent patients than in continent controls.     

Anorectal manometry in the assessment of anorectal function in Parkinson's disease: a comparison with chronic idiopathic constipation

We investigated the role of anorectal manometry in evaluating constipation and anorectal function in 15 patients with Parkinson's disease (PD) and compared results with those of 9 patients with idiopathic constipation (IC) and 8 control (C) subjects. Anal sphincter pressures on voluntary squeeze were lower in the PD patients. Sustained squeeze pressures (mm Hg C versus IC versus PD: 46.8 +/- 5.2 versus 31.2 +/- 3.6 versus 26.6 +/- 3.9; p < 0.05 PD versus C), squeeze duration (seconds: 53.6 +/- 2.5 versus 48.5 +/- 4.1 versus 33.6 +/- 9; p < 0.05 PD versus C) and squeeze index (area under the squeeze curve: 44.0 +/- 2.9 versus 34.5 +/- 3.3 versus 21.4 +/- 2.9; p < 0.001 PD versus C) were significantly lower in the PD group in comparison to the control group. In contrast, none of the parameters of anorectal manometry differed between controls and patients with idiopathic constipation. Some Parkinson's disease patients demonstrated an abnormal, hypercontractile response on testing of the rectoanal inhibitory reflex. Anal sphincter length, basal sphincter pressures, maximal squeeze pressures, extent of relaxation on rectoanal inhibitory reflex and threshold volume for rectal sensation were similar in the three groups. We conclude that an impaired squeeze response is a specific feature of anorectal function in Parkinson's disease. This may indicate direct involvement of the pelvic floor musculature by the parkinsonian disease process.     

Dynamic anal manometry in the assessment of patients with obstructed defecation

Patients with obstructed defecation show no consistent abnormalities when assessed by standard anorectal physiologic methods. With a recently developed technique for dynamic anal manometry, we studied 13 female patients with obstructed defecation and 20 healthy volunteers. Seven parameters of anal function were measured. There were no differences between the median values for the two groups. Seven patients (54 percent; 95 percent confidence limits, 25-81 percent) had anal compliance below the normal range, either during opening or closing of the sphincter at rest (five patients), during squeeze (one patient), or both (one patient). Opening and closing pressures of the sphincter at rest, maximal closing pressure during squeeze, and anal hysteresis were normal. Standard anal manometry did not show any differences between patients and controls. Rectal compliance was lower in patients with obstructed defecation, median difference 5 ml/cm H2O (95 percent confidence limits, 1-9 ml/cm H2O). In conclusion, the more detailed method of dynamic anal manometry shows that some patients with obstructed defecation have a less compliant anal sphincter and a less compliant rectum, but in many patients no abnormal findings can be made.     

Serial evaluation of anorectal function following low anterior resection of the rectum

PURPOSE: This prospective study was performed to serially assess the changes in anorectal function after low anterior resection of the rectum, and to elucidate the mechanisms of functional impairment and the recovery process. MATERIALS AND METHODS: Thirty-two patients undergoing low anterior resection for rectal cancer were evaluated prospectively. Standardized interviews concerning anorectal function and physiologic studies consisting of manometry and balloon proctometry were performed preoperatively, then at 1, 3, and 6 months, and 1 year after the operation. Depending on the length of the residual rectum, patients were divided into two groups: (1) shorter than 4 cm (the short group, n = 18), and (2) longer than or equal to 4 cm (the long group, n = 14). RESULTS: Postoperatively, stool frequency increased and urgency to defecate occurred, which continued until 3-6 months had passed and was more remarkable in the short group. Overall incontinence score increased, which was more remarkable in the short group. Anal resting pressure showed a moderate reduction after 3 months, whereas squeeze pressure did not decrease significantly. Rectoanal inhibitory reflex was postoperatively abolished in almost all patients in the short group, which showed nearly no recovery for 1 year. In the long group, it persisted postoperatively in half the cases, and the reflex returned in a few cases within 1 year. Balloon proctometry revealed overall reduction in rectal capacity and compliance. Although the values tended to recover steadily, they did not reach the preoperative level for 1 year. Urgent volume and maximal tolerable volume remarkably declined, which continued for 1 year and for 6 months, respectively. Rectal compliance also decreased considerably, which continued for 6 months. Most values of rectal capacity tended to be smaller in the short group. CONCLUSION: Impairment of continence after low anterior resection seemed multifactorial, including diminished rectal capacity and compliance, impaired internal anal sphincter tone, and loss of rectoanal inhibitory reflex. Clinical outcome was better and reduction in rectal capacity was less in patients whose rectum remained more than 4 cm. Most of the functional impairments clinically recovered by 6 months postoperation. In the process of clinical recovery of continence, restoration of rectal capacity and compliance and internal anal sphincter tone seemed to contribute a significant degree, while the rectoanal inhibitory reflex did not contribute as much.     

Pudendal nerve terminal motor latency influences surgical outcome in treatment of rectal prolapse

PURPOSE: This study was undertaken to document the effect of pudendal nerve function on anal incontinence after repair of rectal prolapse. METHODS: Patients with full rectal prolapse (n = 24) were prospectively evaluated by anal manometry and pudendal nerve terminal motor latency (PNTML) before and after surgical correction of rectal prolapse (low anterior resection (LAR; n = 13) and retrorectal sacral fixation (RSF; n = 11)). RESULTS: Prolapse was corrected in all patients; there were no recurrences during a mean 25-month follow-up. Postoperative PNTML was prolonged bilaterally (> 2.2 ms) in six patients (3 LAR; 3 RSF); five patients were incontinent (83 percent). PNTML was prolonged unilaterally in eight patients (4 LAR; 4 RSF); three patients were incontinent (38 percent). PNTML was normal in five patients (3 LAR; 2 RSF); one was incontinent (20 percent). Postoperative squeeze pressures were significantly higher for patients with normal PNTML than for those with bilateral abnormal PNTML (145 vs. 66.5 mmHg; P = 0.0151). Patients with unilateral abnormal PNTML had higher postoperative squeeze pressures than those with bilateral abnormal PNTML, but the difference was not significant (94.8 vs. 66.5 mmHg; P = 0.3182). The surgical procedure did not affect postoperative sphincter function or PNTML. CONCLUSION: Injury to the pudendal nerve contributes to postoperative incontinence after repair of rectal prolapse. Status of anal continence after surgical correction of rectal prolapse can be predicted by postoperative measurement of PNTML.     

Experimental model of pudendal nerve innervation of a skeletal muscle neosphincter for faecal incontinence

BACKGROUND: Faecal incontinence is difficult to treat. A variety of reconstructive procedures has been described, but none is entirely satisfactory. This study evaluated the feasibility of cross-innervating a skeletal muscle neosphincter with the pudendal nerve in a canine model. METHODS: Thirty dogs were rendered surgically incontinent (the pudendal nerve was cut and the external sphincter was partially excised). A neosphincter was then created using the semitendinosus muscle. In ten dogs pudendal nerve transposition (PNT) to the nerve to the semitendinosus muscle was performed. Ten dogs were given a dynamic neosphincter by inserting a pulse generator at 6 weeks. The remaining ten dogs served as controls with passive semitendinosus wraps. Anal manometry was performed before operation and monthly for 5 months. Muscle biopsies, performed at the initial operation and at 5 months, were stained for slow- and fast-twitch fibres, and were examined histologically. RESULTS: At 1 month, mean sphincter function was 32 per cent of the preoperative value in the control animals, 34 per cent in the PNT group and 27 per cent in the electrostimulation group; all dogs were incontinent. At 5 months the mean recovery of sphincter function was 42 per cent of the preoperative value in controls, 100 per cent in dogs with PNT (P < 0.001) and 63 per cent in dogs having electrostimulation (stimulator on) (P = 0.02). Six dogs with PNT had squeeze pressures equal to or greater than preoperative levels. At 5 months the ratio of slow to fast fibres was significantly greater in all dogs (control P = 0.01, PNT P < 0.005, electrostimulation P < 0.001). CONCLUSION: Use of the pudendal nerve to innervate a canine skeletal muscle anal wrap produced a functional anal sphincter that was superior to electrically stimulated and passive wraps.     

Functional results after treatment of rectal prolapse with rectopexy and sigmoid resection

Constipation and incontinence are frequent complications of rectal prolapse. Surgery should not only aim to correct prolapse but also improve bowel and sphincter function. From 1986-1991 42 patients with procidentia were treated by rectopexy and sigmoid resection. The mean age was 61.1 years. Thirty-nine patients were available for follow-up examination. Mean follow-up was 54 months. Functional data were collected prospectively before the operation and at follow-up and included clinical parameters, a constipation score, an incontinence score, anal manometry [mean resting pressure (MRP), mean maximum pressure (MMP)], proctography [anorectal angle (ARA)] and colonic transit studies [mean transit time (MTT), rectosigmoid transit time (RSTT)]. The postoperative complication rate was 7.1% (n = 3), mortality was 0%. No recurrence was seen. Constipation complaints improved from 43.6% to 25.6% (p < 0.001) and incontinence from 66.6% to 23.1% (p < 0.001). MRP increased from 36.5 mmHg to 46.0 mmHg and MMP from 90.5 mmHg to 103.0 mmHg (p < 0.001). ARA changed from 102 to 98 degrees (p < 0.001) and correlated with sphincter tone and continence. MTT decreased from 47.8 to 38.5 hours, segmental transit (RSTT) from 21.1 to 12.7 hours (p < 0.001). Our results indicate that rectopexy with sigmoid resection is a safe and effective procedure for rectal prolapse and improves functional disorders of bowel and sphincter.     

The longitudinal muscle of the anal canal

The longitudinal muscle (LM) represents a strong muscular structure of the anal canal situated between the internal (IAS) and the external anal sphincter (EAS). Terminal fibres of this muscle insert at the submucosa of the anal canal, representing the m. canalis ani. Others cross the subcutaneous part of the EAS to become the m. corrugator ani. Thus, the LM connects the visceral and somatic parts of the anal sphincter complex. Histologically ganglionic cells and as Vater-Pacinian corpuscles can be identified inside the LM. Morphology, topography and histology of the LM suggest that this muscle participates in maintaining anorectal continence. It is mandatory that the exact functions of this muscular structure be to elaborated upon, if we are to understand the mechanism of anorectal continence.