“Learn from yesterday, live for today, hope for tomorrow. The important thing is not to stop questioning.”—Albert Einstein
The purpose of this review was to examine the historical aspects of the surgical treatment of anorectal anomalies, and the contributions of “modern” surgeons to the management of these developmental problems. Anorectal anomalies remain among the more complex congenital problems that are seen frequently by the pediatric surgeon. However, pediatric gastroenterologists, adult gastroenterologists, as well as pediatric and adult surgeons can see long-term complications in the treatment of this defect. In the best of all possible worlds, a child would have a normal defecatory pattern without soilage or incontinence. Although treatment outcomes have improved over the last 50 years because of novel and varied approaches to this problem, the majority of children with intermediate or high anorectal defects continues to have debilitating social problems as a consequence of this congenital anomaly. This review looks at the past approaches to the correction of this complex anorectal defect, recognizes the surgical innovators who have addressed problems associated with this congenital anomaly and consequent surgery, and tries to stimulate fresh thoughts in the treatment of this problematic disease.
Until the early 18th century, treatment of anorectal anomalies was confined to surgeries intended to allow evacuation of the meconium and to establish a fecal stream. Typically, these procedures used surgical instruments to make a perineal incision at the site where the anus would be located. Then, by stabbing a bistoury or by plunging a trocar through the pelvic musculature, the surgeon hopefully entered a nearby rectal pouch. Once the rectal opening was created, it was recognized that the surgical tract would close. Repeated dilations of the tract were performed, occasionally treating the dilator with a cicatricial agent to promote fibrosis and thus create a permanent opening. Reports of successful treatment by this means were anecdotally noted into the beginning of the 19th century, although it would be presumed that these were low or possibly intermediate defects. Newborns with high imperforate anus would almost invariably die in the neonatal period.
By the early 1800s, European surgeons, and in particular French physicians, became major innovators in the treatment of these congenital lesions. In 1833, immediately after the skin incision but before dissecting superiorly in an attempt to find the rectal pouch, J.-N. Roux noted forcefully contracting elliptical muscles in the perineum in a nonanesthesized infant. He wrote that these muscles could be important in continence and should be preserved.1 However, the greater surgical community largely rejected his observations as surgery in the preanesthesia era was necessarily performed quickly. Time to more carefully dissect these muscles was felt to be unnecessary and to risk death from the stress of the surgical procedure. The importance of these muscles would not be truly appreciated for another 120 years.
In 1835, Amussat (Fig. 1) described a radically different method of addressing this defect.2 He recognized that the current treatment, basically an incision and drainage of the rectal pouch with creation of a rectocutaneous fistula, was destined to fail in most instances as the pathway created by the surgical dissection would close. To prevent that complication, he recommended performing a larger perineal incision. His incision, an inverted “T” with the horizontal incision located between the ischial tuberosities and the longitudinal limb extended upward toward the coccyx from the transverse limb, exposed the rectal pouch. Identifying the pouch by this exposure, he secured the mucosa and muscular wall of the rectal pouch to the skin, a proctoplasty. Dr. Amussat (in an interpretation of that early report) noted that “… the artificial opening that I have practiced lacks a sphincter… .” Nonetheless, he was optimistic that some form of continence would be achieved eventually. He felt that the morbidity associated with routine surgical incision, but which depended on repeated dilations of the surgically created rectocutaneous fistula, would be avoided. His procedure and modifications of it were the primary operations performed throughout the 1800s. Matas at the end of the century wrote “… The new operation proposed by Amussat … is to be regarded as one of the most conspicuous landmarks in the history of this branch of surgery.”3 Even today this approach of extending the perineal incision upward toward the coccyx and sacrum forms the basis of the procedures in our current era. Survival was achieved, but at a high cost in terms of continence.
Through the latter portion of the 19th century, surgeons became increasingly creative in trying to establish the rectocutaneous anastomosis. Excision of the coccyx, splitting of the sacrum, and even sacrectomy, based on the approach used by Kraske for rectal tumors, was performed in instances of particularly high imperforate anus. Mortality from the treatment of imperforate anus toward the end of the 19th century before the introduction of aseptic techniques was greater than 60%. With asepsis, operative mortality associated with Amussat’s proctoplasty lessened but still approximated 30%.3
Through the 19th century and into the mid 20th century, there was controversy about the use of an “inguinal” colostomy. This idea of entering the abdomen, diverting the fecal stream by securing the bowel to the abdominal skin and opening the colon, was first proposed on the basis of observations and autopsy studies of an infant with rectal atresia by Littre in 1710.4 His proposed procedure came to fruition at the end of the century when first Duboise5 and subsequently Duret6 performed sigmoid colostomies in infants with imperforate anus. Duboise’s patient, whose procedure was performed at 3 days of age, was to pass away 10 days after the procedure, but with a functioning colostomy. Duret’s patient, also an infant with imperforate anus, lived into adult life. A small number of other surgeons also used left-sided colostomies (sigmoidostomies) to relieve the immediate bowel obstruction and allow the infant to grow. At a Paris meeting in the mid 19th century, Chassaignac proposed that a probe passed through the colostomy into the distal colon segment and pressed toward the perineum would facilitate the identification of the distal rectal pouch.7 The surgeon would create the new anal opening over the palpated pouch and then later close the “iliac” colostomy. Others would try this technique through the late 1800s without much success and with reports of rectal perforation.8 However, Rehbein would use a variant of this technique in 1959 and place his finger into the distal colon through the colostomy to identify the sphincter complex.
Most surgeons, with fear of infection seeding the peritoneal cavity, avoided colostomies. Some, including Amussat, used an extraperitoneal approach to form a descending colon stoma (lumbar colostomy).9, 10 This route would prevent bacterial seeding of the abdominal parietes. However, this dissection was technically difficult and rarely used. Even with aseptic technique in the late 1800s, mortality remained greater than 50% if a colostomy was performed, significantly higher than the perineal proctoplasty. This mortality figure pushed surgeons to consider a primary perineal approach to the problem and not use the sigmoid colostomy as a temporizing measure. Until the mid-20th century, colostomies would not be routinely used in the treatment of imperforate anus and would be performed only if the pelvic approach failed.
With the more aggressive perineal operations to address the high rectal pouch, entrance into the abdominal peritoneum was feared. In that era, peritonitis had a prohibitive mortality exceeding that of pelvic sepsis. MacLeod, after having an infant die after a failed perineal approach, wrote of the possibility of doing a celiotomy to free the distal colon and allow it to be brought to the perineum.11 Delagenière in an autopsy series found that MacLeod’s theorized approach was possible and lesions terminating as high as the distal sigmoid could be mobilized and brought to the perineum.12 Despite this “proof” that the procedure was possible, the difficulty of an abdominoperineal operation, in both perioperative and postoperative management, was such that the surgical community regarded this as an operation of last resort.13
Surgical approaches to the imperforate anus became increasingly concentrated at hospitals dedicated to the care of infants and children. However, the surgical technique did not change and the perineal approach was preferred. Through 1932, in 162 cases of anorectal malformations treated at Boston Children’s Hospital, Ladd and Gross reported only a single case using a combined abdominoperineal approach, with most infants approached by a pelvic dissection. Only if the rectum was not readily identified was sigmoid colostomy performed.14 Mortality remained high with imperforate anus, although newborns with anorectal malformations often have multiple congenital anomalies: the VACTERL association.15 Ladd and Gross reported that the mortality of all children with anorectal defects was 26% but they felt that 12 of the deaths were directly related to the other severe associated anomalies. These surgeons estimated in this review of their experience that the mortality directly related to the anorectal malformation was 19%.14
Rhoads and coworkers in 1948 and Norris and coworkers in 1949 reported their results using an abdominoperineal operation to address high rectal lesions.16, 17 Both surgeons described technically successful abdominoperineal procedures, although in both centers the operation was associated with a high perioperative mortality rate. However, the benefits of achieving adequate length to bring the rectum to the pelvis and establish intestinal continuity in the newborn period without a colostomy seemed to outweigh the persistent perioperative mortality. They placed the pulled-through colon by a blind passage through the pelvic musculature, aiming toward the anal dimple. Although Stephens was to shortly present his work regarding the muscles of continence, the abdominoperineal operation was to become the first major change in the operative approach to anorectal anomalies since Amussat’s proctoplasty. The rapid acceptance of this “new” operative approach by the surgical community likely stems from the difficulty and frustration of trying to find a high rectal pouch by the perineal approach in a newborn’s narrow pelvis. It was to become the primary technique used for the next decade and formed the basis of many of the current approaches (ie, Rehbein, Swenson, Mollard).
While the Rhoads and Norris articles addressed the problem of mobilizing the distal large intestine to the perineum, Stephens’ operative approach, reported in 1953 and based on his observations at autopsies and in the laboratory, led to a greater appreciation of the pelvic musculature and the importance of the puborectalis sling in achieving continence.18 It was with this article that the purpose of surgery changed from achieving survival to achieving continence. Stephens’ approach included two incisions. The superior sacral incision, performed at the sacrococcygeal junction, exposed the rectum as well as its frequently associated fistula to the genitourinary system and created a space between the urethra and the anteriorly located puborectalis muscle. Once this path was created, the mobilized rectum would be brought down anterior to the pelvic musculature to the second perineal incision that would act as a neoanus. Stephens’ approach, revolutionary in the dissection of pelvic musculature, failed to address or include the external sphincter complex, which he believed based on his dissections to be absent or deficient. Stephens felt that the puborectalis muscle was the most important muscular component of continence and little effort was expended in trying to identify the external sphincter that more recently is believed to be important in fine continence. He also recommended this definitive operation be performed at 1 year of age after a newborn colostomy had been performed, an unorthodox approach at the time. Before his report, colostomies in the newborn were performed only if the definitive procedure, either as an abdominoperineal or perineal approach, could not be performed in the newborn period.
The great German pediatric surgeon, Fritz Rehbein, published his thoughtful approach to this problem in 1959.19, 20 Different from the posterior approach recommended by Stephens and more in line with the abdominal approach practiced by Rhoads and Norris, he added a pouch “mucosectomy” of the distal rectum to avoid possible disruption of the sacral plexus. Injury to this delicate plexus might lead to urinary and fecal incontinence, a problem that had previously been theorized by Gross. Rehbein proposed to avoid this complication by performing an endorectal pull-through of the more proximal colon through the muscular rectal sleeve and denuded pouch. In his original report, Rehbein felt that the pouch would naturally lead the surgeon to the correct path through the pelvis. By placing a finger in the rectal pouch, a second finger on the perineum and palpating between the two, Rehbein felt he could accurately identify the musculature important in fecal continence. By this “touch” technique, the anal opening would be determined. Unfortunately, in follow-up, it was apparent in some children, particularly with rectal atresias, that the pouch did not pass through the puborectalis sling and simple palpation would not direct the surgeon through the muscles of continence accurately. Rehbein later added Stephens’ method of identifying the puborectalis sling to achieve improved continence with a combination of endorectal pull-though with mucosectomy and sacroperineal dissection, an abdomino-sacro-perineal approach.21
Kiesewetter (Fig. 2) and Turner in Pittsburgh noted fair to poor continence in a number of patients who had an abdominoperineal pull-through operation as initially reported by Rhoads.22 He modified their approach to include identification of the puborectalis sling by a subcoccygeal posterior pelvic dissection, only slightly different from Stephens’ approach. For high rectal atresias, he subsequently added an abdominal mobilization after closure of this sagittal pelvic incision after the pelvic-to-abdominal pathway had been identified with a red rubber catheter. The infant was then returned to a supine position. The distal rectosigmoid was mobilized and the “pathway” identified in the initial sacroperineal dissection was used to guide the distal colon through the puborectalis sling to the previously determined anal opening.23, 24 This approach was based on discussions with Rehbein and was very similar in many aspects. Kiesewetter referred to his approach as the sacroabdominoperineal approach, but most surgeons now refer to these similar techniques as the Kiesewetter–Rehbein approach.
In the late 1960s, Drs. Swenson and Donnellan reported an operation that included features of Rhoads’ initial abdominal procedure as well as realizing the merit of Stephens’ observations about the puborectalis sling.25 Swenson and Grana had previously reported the disappointing results for continence using an abdominoperineal approach.26 The Swenson procedure used an abdominal dissection to mobilize the rectosigmoid and divide the rectourethral fistula. Unlike the widely used posterior sacroperineal dissection, Swenson and Donnellan used a limited anterior pelvic dissection beginning close to the scrotum to pass a clamp between the urethra and puborectalis muscle. With this path bluntly dissected, the mobilized colon was passed from the abdominal cavity through the puborectalis sling. Another major difference in this surgical iteration was that the procedure was performed in the newborn period without a diverting colostomy, similar to Rhoads’ earlier recommendation.
In 1978, the French surgeons, Mollard (Fig. 3), Marechal, and Jaubert de Beaujeu, reported a variation of Swenson’s approach.27 An anterior perineal flap was used to identify the rectourethral fistula, carefully dissecting and displacing the puborectalis sling posteriorly. This approach differed from Swenson’s blunt dissection and was dramatically different from the posterior pelvic dissection advocated by Stephens and largely performed by surgeons of that era. Mollard’s dissection also included the endorectal mucosectomy, as initially proposed by Rehbein and subsequently advocated in North America by Kiesewetter. This technique re-created the anorectal angle by sewing the rectum to a posterior cutaneous location away from the anteriorly based flap. Mollard further modified this technique to tubularize a portion of the cutaneous flap to bring the skin internally to the pulled-through rectum and re-create an anal dimple.28, 29 Laberge and colleagues with a long-standing interest in this anterior approach30 has further modified the Mollard procedure using a sagittal incision as opposed to the retroscrotal flap described in the original operation.31, 32
A major addition to the modern surgical approach to this anomaly came from the works of deVries and Peña (Figure 4, Figure 5), who were to publish their approach, a posterior sagittal anorectoplasty, in 1982.33, 34 Their dissections and anatomical studies led them to believe that there is almost invariably an external sphincter present albeit smaller and more posteriorly located.35, 36 These surgeons used a nerve stimulator to better identify the appropriate anal location. Their posterior sagittal dissection was performed in a subcoccygeal plane, slightly caudal to Stephens’ opening and more similar to Kiesewetter’s dissection, and allowed an identification of the puborectalis and external sphincter complexes. These muscular complexes were divided, if necessary, to mobilize the rectal pouch and ligate the rectourethral fistula. Peña and deVries stressed that opening the rectal pouch and looking inward to the fistula often best identifies the site of the rectourethral fistula. Once identified, the surgeon could leave a small cuff of rectal mucosa and muscularis propria around the fistula and then lift the rectum off the prostate and bladder neck away from the rectourethral fistula site. The authors stressed finally that the rectal pouch may be ectatic, thickened, and abnormal. A wedge resection of the pouch with tubularization of the distal rectum to fit through the sphincter complex is often necessary.
This posterior sagittal approach, popularized by Peña and deVries, with direct visualization of the rectum and genitourinary tract has been used successfully in the treatment of cloacal anomalies, the most complex of anorectal malformations. More intricate in their reconstruction, these infants are more likely to experience problems with fecal and urinary incontinence, although successful reconstruction has been shown to occur in experienced hands.37, 38, 39, 40, 41, 42, 43, 44
The most recently described approach uses laparoscopy to visualize and ligate the rectourethral fistula and minimal pelvic dissection to mobilize the rectal pouch.45, 46 The anorectal sphincter complex is identified on the perineum and serially dilated to allow the rectum to be advanced to the new anal opening. It will need to be determined if continence is better and rectal inertia with constipation is avoided.47, 48
Despite these innovative approaches to this difficult problem, infants with imperforate anus have problems following the “successful” correction of the defect. Surprisingly, it is difficult to compare these various techniques. A factor that has hindered the identification of a universally preferred repair is confusion in the categorization of the anomaly, which has not achieved an internationally recognized standard despite past classifications by several authors, including Stephens and Smith (Fig. 6), pioneers in the management of this problem.14, 49, 50 A recent gathering of international experts in Krickenbeck, Germany, hoped to address these confusions and offer a standardized classification of the defect as well as a consistent assessment of the postoperative course regarding constipation and continence.51
In the current era, approximately half of the children with intermediate or high imperforate anus will have problems related to incontinence, soiling, and/or constipation. Only half will achieve total continence.52, 53, 54, 55, 56, 57 Many of these children will need long-term follow-up by pediatric gastroenterologists and pediatric surgeons, aggressive bowel management programs, and occasionally additional surgery to achieve a reasonable quality of life.58, 59, 60 Most need additional supportive care and have a higher risk of behavioral and emotional disorders.61 At least one author noted that there was improvement in continence based on interviews conducted 10 to 15 years after surgical correction,23 but that optimistic improvement has not been borne out in more recent studies. Adults who had their surgery before surgeons appreciated the importance of the muscles of continence were interviewed and most are incontinent. Eighty-five percent of these adults report significant social difficulties because of their incontinence.62 Although not addressed in this article, many of the children with “low” anorectal defects have problems with constipation.
It becomes apparent as one reviews these outcome studies that the ideal surgical procedure of this anomaly has not been identified.54, 63 This gold standard, as a single operation or staged procedures, would allow the vast majority of children born with anorectal malformations to have normal bowel movements without incontinence. This elusive operation remains the Holy Grail for pediatric surgeons who treat infants with this anomaly. However, these surgical scientists and innovators who have thoughtfully and courageously addressed this complex congenital problem have at least pointed the way.
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