Sacroperineal mobilization versus posterior sagittal anorectoplasty: A study on outcome

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1 Original Article Full text online at Sacroperineal mobilization versus posterior sagittal anorectoplasty: A study on outcome K. Sivakumar Department of Pediatric Surgery, SAT Hospital, Medical College, Trivandrum, IMCH, Medical College, Calicut, India Correspondence: K. Sivakumar, ANUSHAM, GRA-48, Main Road, Gowrisapattom, Pattom, Trivandrum, Kerala , India. kskdranusham@yahoo.co.in ABSTRACT The two main surgical procedures for high and intermediate anorectal malformations (ARM), namely, Stephens and Peña s procedure, are compared in terms of their outcome. Materials and Methods: Fifty-eight patients who had Stephens procedure and 28 patients who had posterior sagittal anorectoplasty (PSARP) are clinically analyzed in terms of associated anomalies, procedural complications, anatomical reconstruction and functional results. Functional results were assessed by Kelly score, voluntary bowel movements and sensation. Statistical analysis of data was done by Chi-square test. Results: There were 34 high and 52 intermediate ARM. Associated anomalies were noted in 32%. Procedure- related complications of urethral injury, bladder injury, neurogenic bladder, anal stenosis and mucosal prolapse were seen in both procedures. Ectopic positioning of anus was seen in 25% of PSARP and 19% of sacroperineal mobilization (SPM). Good circular sphincter creation was seen in 43% of PSARP and 40% of Stephens. Noncontractile sphincter was found more with SPM. In functional results, when assessed by Kelly score, VBM and sensation, there was no difference for high ARM, whereas results were better with SPM for intermediate anomalies. Discussion: A few reports are available in literature comparing PSARP and SPM. Procedural complications of urethral injury and neurogenic bladder are slightly more with PSARP. Ectopic positioning, poor contraction of sphincter are associated with poor results, and creation of good circular sphincter with good squeeze is associated with good results. Functional assessment by Kelly score, VBM and sensation doesn t reveal any difference between two procedures for high ARM, whereas for intermediate anomalies, Stephens procedure seems to give better functional results. KEY WORDS: Anatomical reconstruction, Kelly score, Peña s PSARP, sensation, sphincter, Stephens sacroperineal mobilization, voluntary bowel movements Prof. Douglas Stephens pubo-rectalis sling revolutionized management of anorectal malformations (ARM) in 1953 and remained so for next 30 years till Alberto Peña introduced the concept of posterior sagittal anorectoplasty (PSARP). [1] Most of the centers now practice PSARP, and the question of which procedure is better is still debated. There are several papers published comparing PSARP with other procedures, in terms of complications and functional results, and most of them favor PSARP. There are several objective and subjective studies, but functional result comparison is most difficult due to different scoring systems employed by each surgeon. The aim of this study is to compare and contrast two main surgical procedures for high and intermediate anorectal malformations namely, sacroperineal mobilization (SPM-Stephen s procedure) and posterior sagittal anorectoplasty (PSARP-Peña s procedure) in terms of anatomical reconstruction, complications and functional results. MATERIALS AND METHODS Patients who had either SPM or sacroabdominoperineal (SAP) procedure and those who had PSARP or Abd- PSARP are studied. This study was conducted in patients who were operated during the period of 1988 to 1997, and they were analyzed in 2001 and There were J Indian Assoc Pediatr Surg / Jul-Sept 2006 / Vol 11 / Issue 3 140

2 63 patients who had Stephen s procedure and 28 patients who had Peña s procedure. All cases were done by experienced surgeons or under their supervision. The sex, the type of anomaly based on Wingspread classification, age at which definitive procedure and colostomy closure were done, associated anomalies, immediate and late complications are tabulated. The assessment includes clinical assessment of anatomical reconstruction in terms of cosmetic appearance of anus, lining of anus, prolapse, stricture, location of anus in relation to sphincter, anorectal angle, closing mechanism and squeeze of sphincter assessed by per-rectal examination by a single person. Per-operative and late urogenital complications were analyzed. Functional results were assessed by Kelly score (good is 5-6 points, fair 3-4 points and poor 0-2 points), voluntary bowel movements and sensation. No manometric study was done due to lack of it. The squeeze pressure during perrectal examination was purely subjective and was graded as poor when absent, weak when partially closing and good when completely closing. Level of sphincter squeeze in relation to anal verge was also noted. Voluntary bowel movements and sensation are assessed since according to Peña, if there is VBM and sensation and if there is no need for enema, it is taken as good continence. Patients were followed up till 3-17 years of age. (Mean follow-up 7.3 years) Statistical analysis of data was done by Chi-square test. The result was considered significant if Pearson (P) value was <0.05, and if it was <0.01, it implied much greater significant difference between two variables. RESULTS A total of 91 patients with intermediate or high ARM was studied. Sixty-three patients had SPM/SAP (but only 58 cases were taken up for study since in 5 patients, the anal stenosis was so severe that per-rectal examination was not possible for assessment) and 28 had PSARP. There was no case of Abd-PSARP in this series. Types of anomalies and surgical techniques are illustrated in Tables 1 and 2 Associated anomalies were noted in 32% of cases; of these, 31% were renal anomalies (renal agenesis, crossed fused kidneys, horseshoe kidneys, VUR, hydronephrosis); 21% congenital heart disease (ASD, VSD, DORV, endocardial cushion defects); 17% vertebral anomalies (partial sacral agenesis, lumbar and sacral hemi vertebra); trisomy 21 in 3 patients. Other anomalies seen were undescended testis, hypospadias, cleft lip, cleft palate, deaf-mutes, albinism, etc. Complications: Anal stenosis (those required anoplasty later), mucosal prolapse and bladder injury, more with Stephen s procedure; whereas neurogenic bladder problem more after PSARP; incidence of urethral injury was almost same [Table 3]. One patient with urethral injury later developed recurrent recto-urethral fistula, another developed stricture, all others healed without any problem. Anatomical reconstruction: False positioning of rectum, evident by finding more muscle mass on one side of anus, was seen in 25% of Pena s and 19% Stephen s procedure. Interestingly in PSARP, in 5 out of 7 situations, muscle mass was felt more towards left (false Table 1: Types of anomalies where Stephens procedure done; twenty-three of high ARM had SAP and rest 35 cases had SPM Males-39 Females-19 High-18 Intermediate-21 High-9 Intermediate-10 Rectovesical-8 Recto bulbar Recto-high Recto-low vaginal-2 Recto prostaticurethral-3 urethral-13 vaginal-7 Rectovestibular-8 Anorectal agenesis Anal agenesis High cloaca-2 with out fistula-7 without fistula-8 Table 2: Types of anomalies where PSARP done; none had APSARP Males-23 Females-5 High-5 Intermediate-18 High-2 Intermediate-3 Rectovesical-1 Recto bulbar Recto-high vaginal-1 Recto-low vaginal-2 Rectoprostatic-2 urethral-13 High cloaca-1 Rectovestibular-1 Anorectal agenesis Anal agenesis without fistula-2 without fistula-5 Table 3: Complications seen with Peña s and Stephens procedures Surgery Anal stenosis Mucosal prolapse Urethral injury Bladder injury Neurogenic bladder PSARP-28 2 (7%) 1 (3.5%) 3 (11%) 0 2 (7%) SPM SAP SPM+SAP=63 13 (21%) 8 (13%) 4 (6%) 4 (6%) 1 (1.5%) 141 J Indian Assoc Pediatr Surg / Jul-Sept 2006 / Vol 11 / Issue 3

3 position of rectum more towards right), whereas in Stephen s procedure, in 9 out of 11 cases, muscle mass was felt more towards right (false positioning of rectum more towards left). Good circular sphincter at anal verge with development of good anorectal angle was seen in 43% after Pena s procedure and 40% after Stephen s procedure. The difference is not statistically significant (P value 0.865). Noncontractile taut band-like sphincter was felt in 25% of cases after PSARP and 48% of cases after SPM / SAP. The difference is not statistically significant (P value 0.48). Most of the time, such sphincter tissues are felt 1-3 cm above anal verge. Functional assessment by Kelly Score: No significant difference was seen between two procedures for high ARM [Figure 1]. In case of Intermediate ARM, when good and poor scores are considered, SPM is better [Figure 2]. Functional assessment by voluntary bowel movements and sensation: No difference was seen in case of high ARM [Table 4], whereas there was a highly significant difference (p <0.01) in case of intermediate anomalies [Table 5], favoring Stephens. % of Cases High ARM Kelly Score Good Fair Poor Stephens'(n=27) Peña's(n=8) Figure 1: Kelly Score in high ARM; P value (no significant difference) % of cases Intermediate ARM - Kelly Score Good(p 0.035) Fair(p 0.332) Poor(p 0.042) Stephens'(n=31) Peña's (n=20) Figure 2: Kelly Score in intermediate ARM; P < 0.05 for good and poor results Table 4: High ARM functional assessment by VBM and sensation; difference not significant Procedure VBM Sensation SPM/SAP (n-27) PSARP (n-7) 1 1 P-value Table 5: Intermediate ARM functional assessment by VBM and sensation; difference highly significant Procedure VBM Sensation SPM (n-31) PSARP (n-21) P-value DISCUSSION SPM / SAP is based on the concept of D. Stephens and D. Smith. PSARP is based on the concept of Alberto Peña and Pieter A. de Vries. The concept of puborectalis sling and levator ani sleeve was introduced by D. Stephens in 1953, and this profoundly influenced the management of ARM for next 30 years. Later by 1980, Pieter A. de Vries and Alberto Peña highlighted the functional importance of external sphincter and started PSARP. In this study, an attempt was made by the author to find out the outcome of each procedure based only on clinical parameters, and he arrived at some interesting conclusions. A few reports are available in literature comparing functional results of PSARP and SPM. The associated anomalies are less frequent in our state, which are only 32% as compared to other reports of 40 60%; [2,3] moreover, cardiac anomalies are more than vertebral anomalies in this series. It may be noted that chance of conversion of SPM to SAP in high ARM is nearly 85%, whereas none of the high ARM in PSARP had combined laparotomy. Per-operative complications of urethra injury were slightly more in PSARP, whereas chance of bladder injury was more in cases of SPM. Neurogenic bladder disturbances were more after PSARP. Postoperative neurogenic bladder disturbances were higher after PSARP, probably because all high anomalies are tackled more aggressively through PSARP instead of Abdomino-PSARP. It is stated that PSARP, because it provides a wide exposure, is deceptively prone to complications. Nakayama et al. reported 26% of complications specifically related to the procedure. [4] However, de Vries did not have these complications. [5] In our series also, these injures occurred in early cases of PSARP and they decreased thereafter. There was a question whether neurovesical dysfunction is an association of ARM or whether it occurs J Indian Assoc Pediatr Surg / Jul-Sept 2006 / Vol 11 / Issue 3 142

4 postoperatively. In a study, cystometry and EMG study didn t reveal any difference in neurovesical dysfunction after SPM or PSARP, and no additional neurovesical dysfunction was detected after PSARP. [6] Late problems of anal stenosis and mucosal prolapse were seen more after SAP / SPM. However, anal stenosis and mucosal prolapse were found to be problems common to all. [5] Anatomical reconstruction was assessed mainly on clinical basis in this study, and it revealed that false positioning of rectum occurred in PSARP and SPM. Interestingly, ectopic positioning was more toward right in cases of PSARP and more toward left in cases of SPM. Good circular sphincter with good anorectal angle was seen in nearly 40% of both groups. Noncontractile taut band-like sphincter, usually felt 1-3 cm above the anal verge was seen in nearly 48% of SPM / SAP cases and only in 25% of PSARP cases. So does it mean muscle damage is more after Stephens technique as predicted by Peña? In cases of laparoscopy-assisted anorectoplasty for high ARM, the principle is similar to that of Stephens, where dilatation of tunnel through sphincter done. So are lap surgeons defying the concept of Peña? Literature does not have much data on objective assessment. One such study assessed 16 cases of PSARP by MRI and found 14 anatomical, 4 near-anatomical and 1 ectopic. No such reports are available regarding SPM. Regarding muscle damage, objective assessment by neuroelectrophysiological studies of external anal sphincter revealed that latency of pudento-anal reflex and spino-anal reflex is longer after PSARP compared to SPM, [7] but later another study reported that latency is generally more in ARM before surgery and gets prolonged after PSARP and returns back to pre-operative level by 1-5 months. [8] Manometric evaluation of sphincter contraction is found studied extensively, and several reports are available. No difference in maximum resting pressure is seen between different procedures. [9] R. J. Rintala et al. found that anorectal resting pressure, squeeze pressure were higher in PSARP compared to SPM, and recto-anal reflex was seen in most cases of PSARP, indicating functional internal anal sphincter and in none of SPM cases. [10] But generally speaking, correlation of objective assessment with clinical score is poor and clinical scoring system is different from surgeon to surgeon, so it is not possible to compare the two. Functional results: For high ARM, there was no difference in functional results of SPM and PSARP as assessed by Kelly score [Figure 1], whereas for intermediate anomalies, SPM seems superior [Figure 2]. On assessment by VBM and sensation for high ARM, 143 there was no difference between SPM and PSARP [Table 4], whereas for intermediate anomalies, SPM was far superior [Table 5]. There are various reports comparing PSARP with other procedures. In Pieter A. de Vries series, high and intermediate anomalies treated by PSARP or Abd- PSARP are compared using Kelly score with Stephens and Smiths 25 own cases treated by one of several techniques and 22 treated only by the sacral route. The results are quite similar. [5] In one of Pena s series, with functional assessment by VBM and sensation, it was found that 17 / 22 intermediate RUF had VBM, 23 / 29 high RUF had VBM and 3 / 9 APSARP and 24 / 39 secondary PSARP had VBM. In another study, a comparison of 23 PSARP for high and intermediate with 14 other procedures revealed good Kelly score of 48% vs. 21%, fair score of 48% vs. 58% and poor score 4% vs. 21%. [9] When anatomical reconstruction and functional results were compared, in 7 cases of PSARP where there was ectopic location of anus in relation to the sphincter, 2 had fair and 5 had poor Kelly score. In the case of SPM, out of 11 cases of ectopic location, 3 had fair, 7 had poor and 1 had good score (but this patient is 14 years old now). When there was good circular sphincter with good anorectal angle, the Kelly score was good in 78% of cases and fair in rest of them. Majority of patients with noncontractile sphincter had a poor Kelly score and two patients had a good score, but then, one of them was 8 years old and the other 14 years old at the time of assessment. An attempt was made to see at what age Kelly score improved; the questionnaire in this regard was found difficult for the parents to answer properly. However, most of the good scores were attained by 5-7 years in cases of intermediate anomalies. Noteworthy were the dramatic changes in score that occurred by 5-7 years and when these patients were reviewed by 9-10 years of age; both patients and parents were happy with the results. Fair score inclined to improve as age advanced, whereas most of the poor score cases remained static. Kieswetter and Chang found that there is an evolutionary process in their state of continence, which was not good in early years but became better with each passing year through puberty. [5] Rintala and Lindahl found that fecal continence in patients who had PSARP for high ARM improved by adolescence as constipation disappeared. In their study, 68% of 22 cases, constipated before puberty, came down to 9% by post-pubertal age and the study of manometric correlation established that only the force of voluntary sphincter squeeze correlated with functional results. [11] This was also found to be true in our study where squeeze was assessed by per-rectal examination, and a good squeeze was definitely found associated with good results. In PSARP, out of 12 cases with good squeeze, 7 had good Kelly score and 5 had fair score. In SPM, 21 J Indian Assoc Pediatr Surg / Jul-Sept 2006 / Vol 11 / Issue 3

5 out of 35 had good squeeze and of these, 19 had a good score and 2 had a fair score. Two cases of SAP who had good squeeze had a fair score. For intermediate anomalies, SPM seemed to give better results in this study, but it is to be noted that these cases were done by pioneers in the field or under their supervision. Can others reproduce the results? It is definitely not a procedure meant for a beginner, and new generation of pediatric surgeons are rarely exposed to this procedure since PSARP is in limelight. When those who do PSARP face the situation of LAARP for high ARM, the procedure is like Stephens technique. In this context, it will be appropriate to quote the statement of Prof. F. Douglas Stephens: There are conflicting concepts; you are left to accept or reject such views based on personal knowledge and experience. ACKNOWLEDGMENTS I thank Prof. K. K. Varma, Prof. M. I. Sreekumaran, Prof. Rex Thomas, Prof. Akbar Sherif from Medical College, Calicut; Prof. S. Hariharan, Prof. Noor Sathar and Prof. R. R. Varma form Medical College, Trivandrum, whose case I have followed up for this study. REFERENCES 1. Pieter A. de Vries MD. Historical update. In: F. Douglas Stephens, E. Durham Smith, Anorectal Malformations in children: Update. Alan. R. Liss INC: New York; p Smith ED, Saeki M. Associated Anomalies. In: Stephens FD, Smith ED. Anorectal Malformations in children: Update. Alan. R. Liss INC: New York; p Chalapathi G, Chowdary SK, Rao KL, Samujh R, Narasimhan KL, Mahajan JK, et al. Risk factors in the primary management of Anorectal malformations in North India. Pediat Surg Int 2004;20: Nakayama DK, Templeton JM, Ziegler MM, O Neill JA, Walker AB. Complications of posterior sagittal anorectoplasty. J Pediatr Surg 1986;21: Devries PA. Results of Treatment and Their Assessment. In: Stephens FD, Smith ED. Anorectal Malformations in children: Update. Alan. R. Liss INC: New York; p Kilic N, Emir H, Sander S, Elicevik M, Celayir S, Soylet Y. Comparison of urodynamic investigation before and after posterior sagittal anorectoplasty for anorectal malformations. J Pediatr Surg 1997;32: Yuan Z, Bai Y, Zhang Z, Ji S, Li Z, Wang W. Neural elctro physiological studies on the external anal sphincter in children with anorectal malformations. J Pediatr Surg 2000;35: Kubota M, Suita S. Assessment of Sphincter muscle function before and after posterior sagittal anorectoplasty using a magnetic spinal stimulation technique. J Pediatr surg 2002;37: Tsuji H, Okada A, Nakai H, Azuma T, Yagi M, Kubota A. Follow up studies of anorectal malformations after posterior sagittal anorectoplasty. J Pediatr Surg 2002;37: Rintala RJ, Lindahl HG. Posterior sagittal anorectoplasty is superior to sacroperineal-sacroabdomino perineal pull-through. A long term follow up study in boys with high anorectal anomalies. J Pediatr Surg 1999;34: Rintala RJ, Lindahl HG. Fecal continence is patients having undergone posterior sagittal anorectoplasty procedure for high anorectal malformation improves at adolescence as constipation disappears. J Pediatr Surg 2001;36: Author Help: Sending a revised article 1) Include the referees remarks and point to point clarification to those remarks at the beginning in the revised article file itself. In addition, mark the changes as underlined or coloured text in the article. Please include in a single file a. referees comments b. point to point clarifications on the comments c. revised article with text highlighting the changes done 2) Include the original comments of the reviewers/editor with point to point reply at the beginning of the article in the Article File. To ensure that the reviewer can assess the revised paper in timely fashion, please reply to the comments of the referees/editors in the following manner. There is no data on follow-up of these patients. Authors Reply: The follow up of patients have been included in the results section [Page 3, para 2] Authors should highlight the relation of complication to duration of diabetes. Authors Reply: The complications as seen in our study group has been included in the results section [Page 4, Table] J Indian Assoc Pediatr Surg / Jul-Sept 2006 / Vol 11 / Issue 3 144