Controversy of Single versus Staged Management of Anorectal Malformations
Anorectal malformations’ (ARMs) management has taken strides over the past few decades. The advent of Posterior sagittal anorectoplasty (PSARP) and its acceptance by most people across the globe as standard procedure has given way to a debate of single vs. three-staged repair. After initial hesitancy and lot of skepticism, single-staged repair has very well established its role because of its advantages over the staged procedure. There is enough evidence which suggests that single-staged repair has got equally good outcome as that of staged repair (if not better). Further, one-staged repair offers advantages of lesser morbidity, lesser cost, and lesser burden to the family. The initially thought disadvantages of higher chances of injuries, wound infection and stress to neonates have been countered by growing evidences. The authors agree that staged procedure will continue to stay around for few specific indications like perforation peritonitis, extreme prematurity and special anatomical entities. Further, it can have more important role with advent of laparoscopy and better health infrastructure in future. But with new developments in imaging, scopes and neonatal care, single-staged repair is a feasible and safe modality for treatment of these anomalies.
KeywordsAnorectal malformation Primary PSARP Staged repair PSARP
Anorectal malformations (ARMs) are common pediatric surgical entity with an approximate incidence ranging between 1 in 2000 to 1 in 5000 live births . The incidence varies in different parts of the world; the malformation is more common in few countries like India. There are a few variants which are more common in northern India i.e., pouch colon .
Apart from variations in anatomical type and incidence, the disorder itself has a huge spectrum with simple anomalies requiring one-staged corrective procedure with excellent outcome to complex variants requiring multiple procedures with a guarded prognosis.
As factors like basic health infrastructure, referral delays and neonatal surgical setup vary across different countries; the management of this problem also varies and poses a unique challenge to treating pediatric surgeons. The ultimate goal is to achieve a good functional outcome. With this aim the management has evolved with time based on scientific evidence and understanding of anatomy of these disorders. These things have created a long and colorful history of changing management principle for the achievement of the ideal treatment of ARM and debate among different groups regarding different points.
The selection of the one- or three-stage surgical procedure to treat the disease is the current debate which has divided the pediatric surgery community in two groups; both have their arguments and counterarguments. This article aims to bring out and critically evaluate the advantages and disadvantages of these two methods.
Pre PSARP and PSARP Era
The anatomy of pelvic floor muscle and their variation in ARM patients has evolved ever since the first description of anorectal malformations. Most of the procedures and description of anatomy of ARM were governed by the traditional concepts of pelvic floor muscles which included the puborectalis, pubococcygeous, pubourethralis, iliococcygeous, superficial and deep portion of the external sphincter and internal sphincter muscles [3, 4]. Before the anatomical description of the pelvic floor and its muscles in ARM patients by Alberto Pena, Prof Douglas Stephens’s puborectalis concept formed the backbone of all surgical procedures for ARM [5, 6]. This initially created lot of controversies as all of the previously existing concepts were challenged by Peña et al. [5, 6]. Peña’s group came with the idea of “what one sees, should believe”. They proposed that there is no natural distinction of pelvic muscles responsible for continence into puborectalis, ischiococcygeous, pubourethralis, iliococcygeous muscles or deep and superficial external sphincter muscles. Rather, it is only a theoretical description [7, 8, 9]. As scientific evidence kept growing in favour of Posterior sagittal anorectoplasty (PSARP), it became primary modality at most centers across the world. Though previously performed procedures like Abdominoperineal pull through (APPT), especially for high ARM (where the abdominal approach is required to tackle the fistula) have equally good outcome as PSARP , the utility of such procedures has been enhanced by methods that give a better idea about the site of fistula preoperatively . Further with the advent of Laparoscopic assisted anorectal pull through (LAARP), the advantage of non-division of the muscle has surfaced again. The principle of pulling the bowel through the levator sling under vision forms the backbone of the procedure . This is also followed in previously described procedures like APPT. A meta-analysis has proven that LAARP has equally good outcome as that of PSARP, which reinforces the surgical principle of previously described procedures and their validity .
Advent of Single-stage Repair
Newborn anatomy is not very well developed and the structures are very tiny. One needs to get familiar with anatomy before possibility of performing such a repair.
The chances of wound contamination and dehiscence are very high in single-stage repair. As most believe that first chance is the best chance to achieve good structural correction and scarring from one episode of infection could hamper the life of children by compromising the chances of obtaining optimal bowel function.
Surgeons should be aware about the exact site of the fistula before perineal exploration. In search of rectum, which sometimes lies high in the abdomen, one can easily damage vital structures like posterior urethra, seminal vesicles, vas deferens, and ectopic ureters.
One cannot have distal cologram in one-staged repair which is still considered as the best investigation to delineate the fistula site.
Single-stage Repair: From Possibility to Reality
Studies highlighting the results of primary repair
Total no. of patients and fistula type
Demirbileka S et al. 
47 (Rectovestibular fistula)
Good continence in 96% cases
Liu G et al. 
65 patients (54 boys, 11 girls)
(High - 48, Intermediate - 17)
Not mentioned separately
53.8%: Excellent and good
41.7%: Fair and poor
Adeniran JO et al. 
13 (Boys; Intermediate)
Upadhyaya VD et al. 
27 (Girls; Rectovestibular fistula)
Gangopadhyay AN et al. 
102 (Pouch colon)
Gangopadhyay AN et al. 
Zheng S et al. 
22 (17 boys, 5 girls)
100%- Voluntary bowel movement
Chan K et al. 
27 (Perineal fistula, Krickenbec classification)
100%- Voluntary control
The other advantages of single-stage repair are easier dissection in the neonatal period due to virgin tissue planes with no fibrosis due to pouchitis and no need for bowel preparation. Further, the dilation in neonates is very easy to perform and these children do not remember any kind of procedure performed in the past once they grow up.
In females with vestibular or perineal fistula, both single-stage and staged-repair have been used. Adeniran reported that rectovestibular fistular repair can be safely performed as a one-stage anterior sagittal anorectoplasty with all the above mentioned advantages of one-staged procedure . Wakhlu et al., in their series of 1206 females with single-stage repair reported an overall complication rate of 5% with postoperative wound disruption in 0.68% . Such infections are hugely detrimental for overall continence. Another study by Menon and Rao reported nil wound dehiscence rates in their vestibular fistula patients with one-staged repair . Higher incidence of wound dehiscence has been reported in children with higher mean age. These children have hugely dilated bowel and there are very high chances of contamination. So the single-staged repair should only be reserved for children presenting early and without much dilated bowel. Further, all the patients with intraoperative contamination of the wound should be diverted.
Controversies of Single vs. Staged Management of Anorectal Malformations
The advent of single-staged repair was not unopposed and all the oppositions were not fictitious also. Lots of problems were highlighted with the single-stage management of these anomalies based on facts and evidence.
The opponents argue that significant urologic injuries such as transaction of the bladder neck or urethra, and injury to the vas deferens, seminal vesicles and ureters can occur during primary PSARP. Hong et al. found that 129 of 1003 children had urologic injuries following reconstruction of anorectal malformations. Twenty-six of these children had urethral injuries . This is usually due to lack of a precise anatomy prior to posterior sagittal dissection. For avoiding such injuries, a good distal cologram should be performed in all the cases [35, 36]. Further, the chances of injury are higher in patients with recto bladder neck fistula as the urethra is exposed . If one is not careful, division of presacral fascia can lead to damage to serosa of the bowel at proximal level. Since there is no diversion, such injuries can be detrimental and may lead to significant loss of a healthy bowel and can have a devastating long term impact.
Surgical Site Infection and Dehiscence
A higher chance of wound infection and dehiscence leading to scarring and poor continence is one of most feared complication. Though superficial wound infection is common, it rarely causes deep infection resulting in wound dehiscence (Table 1).
Stress to Neonate
Primary PSARP is performed in a jack-knife position (prone and knee-elbow position with buttocks elevated) which is known to cause vomiting with aspiration, even with nasogastric tube in-situ. This has been observed as the major drawback to positioning for PSARP [37, 38]. Further, the procedures like neonatal PSARP or APPT can cause a large amount of blood loss and also the duration of surgery is long. These all add to the stress in a physiologically compromised child and due to splinted diaphragm during surgery; it may be impossible for the anesthesiologists to maintain an adequate saturation during the procedure. The staged procedure holds a distinct advantage in this respect. So authors have included congenital heart disease, aspiration pneumonitis, evidence of sepsis and deranged blood picture as the criteria that contradict single-stage repair [37, 38].
But with the advent of better neonatal care and advances in anesthesia, most of these cases can be successfully managed in the neonatal period. In authors’ experience of management of these children with single-stage, they have observed that depriving such children of one-staged correction merely based on the time of presentation is not correct. Sometimes wide fistula in urethra tends to decompress their abdomen very effectively .
Problems with Dilated Bowel
One of the major problems cited as hindrance for one-staged correction is the dilated distal bowel [11, 12]. The delayed presentation is very common in few setups like that in developing countries and even if presentation is at birth, the terminal bowel is dilated. In staged procedure, there is effective decompression of the gut at the time of colostomy. Further, Peña et al. proposed tapering enteroplasty during the PASRP to bring the bowel in the sphincter complex. Tapering during one-staged procedure is associated with very high chances of wound dehiscence.
In authors’ experience and as per other authors like Moore et al., there is absolutely no problem in closing the bowel within the premise of sphincter as the terminal portion is not dilated and placation is not required to achieve good results [13, 20].
PSARP has got a multiple procedure related complications. PSARP performed in the infancy period has a distinct advantage as the structures are much larger as compared to the neonatal period. Further, the identification is usually facilitated by preoperative pressure augmented distal cologram and technical modifications as distension of the distal bowel loop with saline preoperatively. In neonatal PSARP, these advantages are definitely lacking.
But in authors’ experience, the dilated terminal bowel with meconium gives a distinct visual edge, which makes its identification extremely easy. However, it is cautioned that the younger surgeons shall definitely have a longer learning curve than that required for a staged procedure.
Per-operative Abdominal Decompression
Another distinct disadvantage of single-stage procedure is persistent abdominal distension in the postoperative period. As the procedure is performed in jack knife position and buttock is higher in position, adequate decompression is usually not achieved preoperatively.
This can be very well managed by careful pressure on the abdomen after the sagittal wound repair is complete and just before the anoplasty. In authors’ experience, this maneuver leads to very good abdominal decompression without increasing the chances of infection.
Single-staged vs. Staged Repair in Next Decades
The biggest argument in favour of three-staged repair of an ARM is pre-operative better knowledge of the anatomy [35, 36]. The pressure augmented distal cologram provides an excellent way to delineate the exact site of the fistula . Every single child out of hundreds is precious, and it is not acceptable even if a single case with complication occurs because of exploration in the neonatal period.
No doubt, the chances of such mishaps are slightly higher with single-staged repair, but these can be minimized by proper training and most of these complications are amenable to surgical repair in the same sitting with good outcome. Further, authors have observed cases with rupture and spillage of dye intra peritoneally with intense inflammatory response in a few of their cases which were performed by inexperienced radiologists. The advent of excellent new imaging modalities has taken away or nullified this advantage of staged-repair in a great way. Pre-operative neonatal pelvic MRI scans are able to delineate the relation of the fistula and bowel extent with great success . Further, in the same sitting it is helpful in providing other vital information like tethering of cord, sacral agenesis or other associated anomalies with great accuracy. It would not be an exaggerated statement that with refinements in future, MRI pelvis would become a routine investigation in cases of ARM and has the potential to very well become the gold standard for cases of single-staged repair.
Taking the argument to one step ahead is the development of excellent neonatal cystoscopes for preoperative diagnosis of the site of the fistula. Though different reports have given variable figures about their sensitivity and specificity and their utility at present, technological advancements are definitely going to increase their use in such cases with great success .
Last but not the least, staged repair is the only way to proceed in cases with bowel perforation, common cloacae and extreme prematurity. Further, anomalies like common cloaca can only be managed by staged repair. It can be argued that said that staged repair holds good in all conditions and has no distinct contraindication and can be life saving in a lot of situations. Further, with increasing awareness, better medical infrastructure, decrease in the number of drop outs and the advent of laparoscopy, staged repair can be performed with a lot of advantages and very low risk for complications. The staged repair has led the path for improved outcome in patients with ARM.
The single-staged repair of ARM has slowly but surely taken the centre stage. In the backdrop of advances in neonatal care, imaging and endoscopes, one-staged repair is bound to become more popular modality for the management of ARM. But staged repair is going to hang around for specific physiological and anatomical entities and may have a distinct advantage in the future with improved medical infrastructure, decreasing poverty and the advent of laparoscopy.
Both authors have equally contributed in writing the manuscript. ANG will act as guarantor for the paper.
Compliance with Ethical Standards
Conflict of Interest
Source of Funding
- 2.Narasimharao KL, Yadav K, Mitra SK, Pathak IC. Congenital short colon with imperforate anus (pouch colon syndrome). Ann Pediatr Surg. 1984;1:159–67.Google Scholar
- 3.Stephens D, Smith D. Ano-rectal malformation in children. Chicago: Year Book Medical Publisher Inc; 1972. p. 14–32.Google Scholar
- 8.deVries PA, Peña A. Posterior sagittal anorectoplasty. J Pediatr Surg. 1982;17:638–43.Google Scholar
- 10.Gangopadhyay AN, Pandey V, Gupta DK, et al. Assessment and comparison of fecal continence in children following primary posterior sagittal anorectoplasty and abdominoperineal pull through for anorectal anomaly using clinical scoring and MRI. J Pediatr Surg. 2016;51:430–4.CrossRefPubMedGoogle Scholar
- 14.Freeman NV, Burge DM, Soar JS, et al. Anal evoked potentials. Z Kinderchir. 1980;31:22–30.Google Scholar
- 23.Peña A. Advances in anorectal malformations. Semin Pediatr Surg. 1997;6:165–9.Google Scholar
- 31.Elhalaby EA. Primary repair of high and intermediate anorectal malformations in the neonates. Ann Pediatr Surg. 2006;2:117–221.Google Scholar
- 37.Hutson JM, van der Putte SCJ, Penington E, Kluth D, Fiegel H. The embryology of anorectal malformations. In: Holschneider AM, Hutson JM, editors. Anorectal malformations in children. Heidelberg: Springer; 2006. p. 49–63.Google Scholar