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At least 19 recordsLinked to original sources

The relative proportions of type I and type II muscle fibers in the external sphincter ani muscle at different ages and stages of development--observations on the development of continence.

The external sphincter ani muscles were partially or completely removed from 11 fetuses, 3 infants, 2 children and 12 adults, none of whom had had anorectal disease and all of whom had died of diseases not affecting the anorectal organ of continence. Muscle fiber-typing was carried out. In the fetuses ages 26-40 weeks, we found a predominance of Type II (rapid) fibers. With increasing gestational age Type II fibers started to diminish along with a simultaneous increase in Type I (slow) fibers. At the same time, stromal restructuring took place. Three infants, ages 1, 2 and 10 months, showed further increases of Type I fibers, until finally, in the two older children studied (5 and 8 years), there was a predominance of Type I fibers. This persisted in adults between ages 56 to 70, but after age 70 Type I fibers diminished, so that the ratio of slow to rapid fibers in the 78 to 81 year-old group was 3:2. This study shows that in contrast to other skeletal muscles the fiber distribution in the external sphincter ani muscle is not established from the beginning, but is the result of a developmental process. The predominance of Type II (twitching) fibers explains the state of reflex continence of the young infant. With increasing maturation of tonic Type I fibers, an additional voluntary component to continence is made possible with the help of the supporting pelvic musculature. This maturation is determined by the increasing strain on the pelvic floor as the child learns to sit and walk.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Early repair of an external sphincter ani muscle and rectal mucosal dehiscence.

Little information is available to assist in the management of a dehiscence subsequent to a fourth degree episiotomy repair. Delayed repair of the external sphincter ani muscle and rectal mucosa may result in weeks or months of disability and inconvenience for these women. A series of eight women is presented whose fourth degree episiotomy repair dehiscence was managed by early puerperal repair. The details of wound and bowel preparation, the operative technique, and postoperative care are described. Because all eight women had a successful repair, the authors believe that early surgical correction is an acceptable treatment for this puerperal complication.

Anal Canal↗

A wrap-around procedure using the gluteus maximus muscle for the functional reconstruction of the sphincter in a case of anal incontinence.

A successful case in which a wrap-around procedure using the gluteus maximus muscle for the functional reconstruction of anal incontinence has been described. The case was a 38-year-old woman whose sphincter ani muscle was severed by the perineal incision at the time of delivery. Muscle-tightening of the levator ani and sphincter ani muscles was performed, and the distally based bilaterally split gluteus maximus muscle flap produced a forceful rectal contracting function.

Adult↗

Development of the reproductive system in turkeys with a high or low susceptibility to prolapse of the oviduct.

Lines of turkeys selected for rapid growth and high meat yield have an increased incidence of prolapse of the oviduct compared with unselected or traditional strains of turkeys. The development of the reproductive system and changes in plasma estrogen concentrations were compared in sire line and traditional turkeys with the aim of identifying any morphological or hormonal differences that could be associated with the high incidence of prolapse in the male line. Four turkeys from each strain were killed weekly from 0 to 7 wk postphotostimulation, and samples from prolapsed birds were obtained from field cases. There were no differences in the rate of development of the ovary, oviduct, uterus, vagina, sphincter ani muscle, or muscular cord of the ventral ligament between the two strains that could predispose the sire line to prolapse. Histological investigation of the uterus, vagina, muscular cord of the ventral ligament, and sphincter ani muscle 5 wk postphotostimulation in traditional, sire line, and prolapsed sire line turkeys did not reveal any differences that could be associated with prolapse. No prelay peak in plasma estradiol concentration was observed in either strain, and there was no evidence to suggest that plasma estradiol was higher in the sire line compared with the traditional turkeys. It was concluded that prolapse of the oviduct in sire line turkeys was not associated with any anatomical abnormalities or high plasma estradiol during reproductive development.

Anal Canal↗

[Muscle grafts in the reconstructive surgery of rectal sphincter].

Analysis of experimental (146 operations) and clinical (14 patients) material provides the grounds for recommending plastics with muscles on a mobile neurovascular pedicle to be included in the complex of surgical rehabilitation of patients with incompetence of the sphincter ani muscles. Optimization of the functional results of such operations holds much promise for the use of the method of muscular plastics on a mobile neurovascular pedicle in proctology.

Anus Diseases↗

A comparative study of the human external sphincter and periurethral levator ani muscles.

Specimens from the human male and female external urethral sphincter and the periurethral levator ani muscle have been examined using histochemical and electron microscopic techniques. In both sexes the external sphincter consists of a single population of type I (slow twitch) fibres with a mean diameter of 17.47 +/- 0.7 micrometers in the absence of muscle spindles. In contrast, the periurethral levator ani possesses muscle spindles and the constituent fibres form a heterogeneous population of type I and type II (fast twitch) fibres, with mean diameters of 45.5 +/- 0.8 micrometer and 59.5 +/- 3.4 micrometers respectively. These findings indicate that the external urethral sphincter is functionally adapted to maintain tone over prolonged periods and may be of considerable importance in producing active urethral closure during continence. The anatomical location and fibre characteristics of the levator ani muscle suggest that these fibres actively assist in urethral closure, particularly during events which cause elevation of intra-abdominal pressure. In view of the differences in fibre characteristics between the external urethral sphincter and the levator ani, EMG activity recorded from a single site in the levator ani may not be representative of the functional status either of other levator ani muscle fibres or of the external urethral sphincter.

Adenosine Triphosphatases↗

Quantitative electromyographic analysis of levator ani and external anal sphincter muscles of nulliparous women.

OBJECTIVES: Our aims were to introduce a method of digital quantitative electromyography of the levator ani and external anal sphincter muscles and to establish reference values. STUDY DESIGN: Fifteen nulliparous, symptom-free women underwent concentric needle electromyographic examination of the levator ani and external anal sphincter. We sampled the levator ani transvaginally at 4 sites and the external anal sphincter at 2 sites. The signal was filtered and amplified, and digital recordings were made at 3 levels of voluntary activation at each site. Analyses of motor unit action potentials and interference patterns were performed with the use of these taped signals. Normal ranges were generated and compared with those established for other striated muscles. RESULTS: The mean age of the subjects was 28.7+/-7.5 years. A median of 24 motor unit action potentials was recorded in each levator ani, and a median of 6 was recorded in each external anal sphincter. Parameters of the levator ani action potentials were significantly greater than those of the external anal sphincter in amplitude (0.48 vs. 0.37 mV; P =.001), duration (10.40 vs. 8.27 ms; P =.002), number of turns per second (2. 80 vs. 2.28; P<.001), and area (0.65 vs. 0.36; P<.001). Parameters of the interference patterns were significantly greater in the levator ani than in the external anal sphincter in number of turns per second (241.6 vs. 183.9; P =.015), amplitude (302.7 vs. 225.3 microV; P<.0001), activity (95.6 vs 61.2; P =.004), envelope size (861.1 vs 567.6 microV; P<.0001), and number of small segments (105. 8 vs 81.4; P =.047). There were no significant differences between levator ani, external anal sphincter, and published parameters from the biceps muscle with regard to amplitude and duration of motor unit action potentials. CONCLUSIONS: Electromyography of the levator ani and external anal sphincter is feasible and well tolerated. Our findings confirm that the levator ani muscle has larger, more readily recruited motor units than does the external anal sphincter. Ranges for important quantitative electromyographic parameters for these muscles are similar to those published for the biceps.

Action Potentials↗

[Electrophysiologic diagnosis of neurogenic bladder in children with myelodysplasia].

Ninety-seven children with neurogenic bladder and myelodysplasia were subjected to complex examination. The somatic innervation of the sphincter urethrae externus and sphincter ani muscles was appraised by the method of sacral guided reactions by a CT-01 electromyograph and by an original method consisting in registration of the reflex response of the named anatomical structures according to the fluctuations of the intraurethral and intraanal pressure. It was established that maintained, partly disturbed, and absolutely absent somatic innervation of the sphincters of the bladder and rectum is encountered in patients with myelodysplasia. The more the innervation of the sphincters disturbed is, the more the urinary bladder is excluded from the "accumulation-evacuation" urodynamic cycle and the lesser the probability of disorders of urodynamics of the upper urinary tract is, and vice versa. The obtained information is important in choosing the therapeutic tactics for patients with a neurogenic bladder.

Anal Canal↗

Topography of the inferior rectal artery: a possible cause of chronic, primary anal fissure.

The authors believed that it might be possible to explain the local frequency of the anal fissure at the posterior commissure by an anatomic relationship, and examined the blood supply of the anus. The inferior rectal artery is demonstrated by postmortem angiography and by manual preparations (N = 41) and histologic study after angiography of the vessels (N = 10). The blood supply at the different sites of the anal canal are demonstrated by a morphometric study (N = 20). The inferior rectal artery presents two variants in the postmortem angiographies, type 1 (85.4 percent) and type 2 (14.6 percent). In type 1, the posterior commissure is less perfused than the other sections of the anal canal. In addition, the blood supply may be more compromised by contusion of the vessels passing vertically through the muscle fibers of the sphincter ani internus muscle during increased sphincter tone. The role of topography in the pathogenesis of the primary anal fissure is illustrated in a model.

Anal Canal↗

Updated recommendations on ultrasonography in urogynecology.

Ultrasound is a supplementary, indispensable diagnostic procedure in urogynecology; perineal, introital, and endoanal ultrasound are the most recommended techniques. The position and mobility of the bladder neck can be demonstrated. In patients undergoing diagnostic work-up for urge symptoms, ultrasound occasionally demonstrates urethral diverticula, leiomyomas, and cysts in the vaginal wall. These findings will lead to further diagnostic assessment. The same applies to the demonstration of bladder diverticula, foreign bodies in the bladder, and bullous edema. With endoanal ultrasound, different parts of the sphincter ani muscle can be evaluated. Recommendations for the standardized use of urogenital ultrasound are given.

Female↗

[Perineo-transano-abdominal resection of the rectum (author's transl)].

The operative procedure described by the author, is a combined perineal and abdominal procedure for resection of the rectum. The first step is a perineal approach: patient placed in lithotomy position. The rectum is dissected free of the sphincter ani muscle. The second step perineal and abdominal: patient being placed in a semilithotomy position draped for work in the abdomen and at the same time, in perineum: the sigmoid brought down preferably if it found free of any pathology. On 18 cases of cancer, of the rectum, even some of large volume: when the inferior limit of the lesion was from 6 to 12 mc, above the anus, this procedure was carried on with good post-operative results.

Abdomen↗

The pathogenesis of hereditary congenital malformations of the anorectum in the pig.

The pathogenesis of anorectal malformations was studied in 41 abnormal embryos, foetuses and newborn pigs descended from a herd in which this anomaly was caused by a hereditary trait. The principal development error was found to be situated in the cloacal plate, of which a dorsal part of variable size was missing. This defect impeded the normal migration of the dorsal cloaca and adjacent structures along the dorsal border of the plate to the body surface of the tailgroove. Correlated to the size of the cloacal plate defect diverse types of anorectal malformations may develop ranging from slight abnormalities such as anal stenosis and perineal or vulvar ectopic anus to more serious anomalies such as imperforate anus of low, intermediate and high types. In the cases with imperforate anus a communication with the urogenital system is always formed, although it may disappear later in some animals. This communication which represents a persistent cloaca, has to be considered as an ectopic anorectal canal according to its origin and structure. The abnormalities of the internal and external sphincter ani muscles and puborectal muscles are secondary although distinctly correlated to the malformations of the epithelial structures.

Abnormalities, Multiple↗