pelvic organ prolapse ( pop ) is extremely common , affecting up to 50% of parous women . a reoperation rate within 10 years of the primary prolapse surgery has been reported as high as 17% . the unacceptable surgical failure rate led surgeons to enforce the native tissue repairs with biological graft or synthetic mesh . level 1 evidence has proved that the use of synthetic mesh increased the anatomical cure rate in anterior vaginal wall repair but not in posterior vaginal wall repair . yet , mesh - related complications , including dyspareunia , mesh exposure , and mesh erosion are being reported with increasing frequency and negatively impacted patient quality - of - life . these findings suggest that urogynecologists should make a balance between anatomical cure and patient quality - of - life when using synthetic mesh to repair the pelvic floor . improvement in patient quality - of - life involves functional recovery , such as improvement of urinary , bowel , and sexual function . however , few studies have looked at the effect of posterior vaginal wall repair with mesh on bowel function . the aims of the study were to use anorectal manometry to compare bowel function outcome in pop patients who underwent prolapse repair with or without trans - vaginal synthetic mesh in the posterior vaginal compartment and specifically to determine whether the use of mesh was better for retention and improvement of anorectal function . between december 2011 and may 2012 , 22 women were referred to our outpatient clinic at the peking union medical college hospital for trans - vaginal mesh surgical correction of severe symptomatic pop ( overall stage iii or iv ) using trans - vaginal mesh ; all 22 were enrolled in the study . exclusion criteria were gynecological pathology in addition to prolapse and previous prolapse surgery or hysterectomy . in addition , patients would be excluded from the study if they had medical conditions , such as diabetes mellitus , hypothyroidism or irritable bowel syndrome that could affect anorectal physiology or cause bowel symptoms . the study was approved by the medical ethics board at the peking union medical college hospital ( s-453 ) . preoperative evaluations included medical history , the pop - quantification ( pop - q ) score measured determining prolapse severity , a chinese validated quality - of - life questionnaire ( the pelvic floor impact questionnaire short form-7 [ pfiq-7 ] ) and anorectal manometry . two surgeons performing all the procedures were blinded to the allocation , and another urogynecologist who neither participated in the surgeries nor knew the mesh status achieved anorectal measurements , pfiq-7 and pop - q scores pre- and post- operatively . the data were finally collected and analyzed by the investigator who knew the group information . anorectal manometry was performed using the solar gi pressure measurement system ( mms , enschede , the netherlands ) . the rectum was emptied before anorectal manometry , and the patient was put in the left lateral decubitus position . during the test , a catheter with four water - perfusion channels was inserted into the anus and placed in the zone of the anal canal with the highest pressure . the maximal anal resting pressure ( marp , a function of the internal anal sphincter ) and the maximal anal squeeze pressure ( masp ) ( a function of the external anal sphincter ) were measured by asking the subjects to rest for 2 min and voluntarily contract the anal sphincter as long as possible . the subject was then instructed to voluntary bowel movements ( straining test ) so we could measure intra - rectal pressure and anal canal residual pressure during defecation . while straining to defecate , the maximal intra - rectal pressure ( a ) clearly exceeded the anal residual pressure ( b ) in order for a bowel movement to occur , so the pressure difference ( p ) between a and b reflected defecation physiology . the straining test result was considered a dyssynergic defecation pattern if there was an inappropriate increase or if the relaxation was < 20% of the basal resting pressure . the operative methods included posterior compartment repair with or without synthetic mesh along with anterior and apical compartment reconstruction if necessary . the choice of operation method was made based on each patient 's pop - q stage , age , and sexual function , and the patient 's preference was considered as well . based on the use of mesh , the patients were divided into two groups that are , a mesh group and a nonmesh group . in the mesh group , we performed total pelvic floor reconstruction with commercial mesh kits such as total prolift ( ethicon , somerville , nj , usa ) or prosima ( ethicon , somerville , nj , usa ) . for the nonmesh group , we performed traditional colporrhaphy for posterior pelvic floor , but reinforced the anterior and the apical pelvic floor using the modified pelvic floor reconstructive surgical method or sacrospinous ligament fixation ( sslf ) . modified pelvic floor reconstructive surgery is a method for repairing the anterior and apical vaginal wall using two pieces of mesh that are cut from one 15 cm  10 cm piece of gynemesh ( ethicon , somerville , nj , usa ) . the same subjective and objective assessments of surgical outcome were repeated 3 months after surgery . anorectal manometry values were also reexamined , including anal canal resting and maximal squeeze pressures , rectal and anal pressure change during defecation . pop - q stage ii or a greater prolapse in any compartment postoperatively was usually defined as failure of the procedure . a two - tailed t - test was used for comparison of continuous data between posterior repair in the mesh and nonmesh groups . the two - tailed , paired t - test was used to calculate probability values for change from baseline to the 3 months postoperative follow - up . a value of p < 0.05 was considered as statistically significant . all statistical analyses were performed using statistical software ( spss version 17.0 ; spss inc . , chicago , il , usa ) . the operative methods included posterior compartment repair with or without synthetic mesh along with anterior and apical compartment reconstruction if necessary . the choice of operation method was made based on each patient 's pop - q stage , age , and sexual function , and the patient 's preference was considered as well . based on the use of mesh , the patients were divided into two groups that are , a mesh group and a nonmesh group . in the mesh group , we performed total pelvic floor reconstruction with commercial mesh kits such as total prolift ( ethicon , somerville , nj , usa ) or prosima ( ethicon , somerville , nj , usa ) . for the nonmesh group , we performed traditional colporrhaphy for posterior pelvic floor , but reinforced the anterior and the apical pelvic floor using the modified pelvic floor reconstructive surgical method or sacrospinous ligament fixation ( sslf ) . modified pelvic floor reconstructive surgery is a method for repairing the anterior and apical vaginal wall using two pieces of mesh that are cut from one 15 cm  10 cm piece of gynemesh ( ethicon , somerville , nj , usa ) . the same subjective and objective assessments of surgical outcome were repeated 3 months after surgery . anorectal manometry values were also reexamined , including anal canal resting and maximal squeeze pressures , rectal and anal pressure change during defecation . pop - q stage ii or a greater prolapse in any compartment postoperatively was usually defined as failure of the procedure . a two - tailed t - test was used for comparison of continuous data between posterior repair in the mesh and nonmesh groups . the two - tailed , paired t - test was used to calculate probability values for change from baseline to the 3 months postoperative follow - up . a value of p < 0.05 was considered as statistically significant . all statistical analyses were performed using statistical software ( spss version 17.0 ; spss inc . , chicago , il , usa ) . in this study , 22 patients underwent surgery for pop . of these , 17 patients were available for a 3 months follow - up examination . of the 17 patients , 5 underwent pelvic floor reconstruction with prosima , 2 underwent using total prolift , 8 had modified pelvic floor reconstructive surgery , and 2 underwent sslf . concomitantly , we performed vaginal hysterectomies in all 17 patients [ figure 1 ] . based on whether mesh was used to reinforce the posterior compartment , the subjects were divided into two groups , the mesh group ( n = 7 ) and the nonmesh group ( n = 10 ) . the baseline patient characteristics are shown in table 1 ; none of the characteristics were significantly different between the groups ( p > 0.05 for all comparisons ) . a total of 3 patients ( 42.9% ) in the mesh group and 5 patients ( 50% ) in the nonmesh group had constipation according to the rome iii criteria . patient characteristics sd : standard deviation ; bmi : body mass index ; pop - q : pelvic organ prolapse - quantification . there were no significant differences between the mesh group and the nonmesh group in terms of the pop - q measurements and pfiq scores either at baseline or at the 3 months follow - up . at follow - up , the pop - q measurements aa , ba , ap , bp , c , and d had improved significantly in both two groups compared to baseline ( p < 0.05 ) [ table 2 ] . the pfiq-7 scores were lower at the 3 months follow - up than at baseline in both groups , but the difference was only significant for the nonmesh group ( p < 0.05 ) . objective and subjective measures before and 3 months after surgery sd : standard deviation ; pfiq-7 : pelvic floor impact questionnaire short form-7 ; preop : preoperative ; postop : postoperative ( 3 months after 
 surgery ) . values are reported as mean  sd . the anorectal manometry results are shown in table 3 . for the mesh group , the preoperative maximum anal resting pressure ( marp ) and the masp values were 38.27  19.56 mmhg and 85.29  37.88 mmhg , respectively . for the nonmesh group , the preoperative marp and masp values were 39.61  11.36 mmhg and 93.78  20.67 mmhg , respectively . postoperatively , the marp value or the masp value increased slightly from the baseline level in the two groups , but the differences were not significant ( p > 0.05 ) . anorectal manometry outcomes before and 3 months after surgery marp : maximum anal resting pressure ; masp : maximum anal squeeze pressure ; p : anorectal pressure difference during defecation . * p < 0.05 compared with preoperative marp for the nonmesh group . at baseline , the anal residual pressure during defecation was significantly higher than the maximal resting level ( p < 0.05 ) for the nonmesh group . postoperatively , the anal residual pressure had decreased significantly compared with the preoperative level ( p < 0.05 ) and became not significantly different from the resting status ( p > 0.05 ) . there was a statistically significant increase in rectal pressure in the mesh group 3 months after surgery ( p < 0.05 ) . the postoperative p increased from 8.12  22.19 mmhg to 25.71  27.20 mmhg and from 0.87  25.47 mmhg to 17.66  16.19 mmhg in the mesh and nonmesh groups , respectively ; only the difference in the nonmesh group was significant ( p < 0.05 ) . before the surgery , 2 of the 7 patients ( 28.6% ) in the mesh group had dyssynergic defecation and had not improved at all 3 months after the surgery ; however , in the nonmesh group , the percentage of patient with defecation dyssynergia decreased sharply from 80.0% ( 8/10 ) to 20.0% ( 2/10 ) . in china , posterior colporrhaphy is considered the standard procedure for correcting the prolapse of the posterior compartment . however , this procedure carries a high risk of failure , especially for advanced pop . to date , a number of synthetic meshes have been used in posterior pelvic compartment repair to reinforce the intrinsic tissue defect . notably , repairs that use synthetic mesh have an 8197% anatomical success rate at > 1-year follow - up and have lower recurrence rates compared with traditional vaginal colporrhaphy . although the evidence shows better anatomical cure of prolapse with the use of synthetic mesh , the short- and long - term functional effects after repair must also be considered in clinical practice as mesh - related complications can develop . huang et al . reported that trans - vaginal pelvic reconstructive surgery using the prolift kit improves urogenital distress inventory-6 scores significantly after a median of 24.5 months of postoperative follow - up . another study demonstrated that the vaginal repair using the prosima system offers significant improvements in pelvic symptoms , quality - of - life , and sexual function 1-year after surgery . however , a cochrane review that was updated in 2010 and that included 40 randomized or quasi - randomized controlled trials concluded that there was no improvement in functional and patient - centered outcomes , as measured by validated pelvic floor questionnaires , for anterior compartment repair using polypropylene mesh . research related to improved function or improved quality - of - life outcomes after posterior vaginal wall repair is sparse , and very few manometry studies have evaluated anorectal function after pop correction surgery . to our knowledge , this is the first study to compare bowel functional outcome of posterior vaginal wall repair with mesh versus without mesh using both subjective and objective measures . we found that the nonmesh group had a significantly lower anal residual pressure and a significantly increased rectum - anus p postoperatively . these changes suggest that when self - tissue rather than synthetic mesh is used in posterior vaginal wall repair , the anal sphincter could relax more during evacuation , helping the rectum squeeze contents out of the anus and improving defecation coordination toward normal physiology . in the mesh group , however , relaxation of the anus remained impaired after the operation , as there was no significant alteration in anal pressure during defecation . these patients had to increase rectal pressure to compensate in order to maintain the anorectal p and therefore achieve a bowel movement . this is why the percentage of patients with defecation dyssynergia decreased sharply from 80.0% to 20.0% in the nonmesh group , while no such decrease was seen in the mesh group . these findings indicate that posterior vaginal wall repair without mesh could improve the anorectal motor function of pop patients better than repair using mesh . there are two possible explanations for the differences we found between mesh versus nonmesh repairs . first , a bridge repair that reconstructs the posterior vaginal wall using self - tissue has less of an effect on anorectal physiology compared to repair with synthetic mesh , which involves the placement of foreign material into the retro - vaginal space . in fact , some patients in the mesh group complained that they felt incapable of straining during evacuation after undergoing posterior pelvic repair with mesh . second , the vaginal bridge repair benefited from apical support with mesh even when there was no synthetic mesh to enforce the posterior pelvic floor . these outcomes illustrate petro 's integrity theory that there is a complex interplay that is , independence but divergence , among different pelvic compartments and delancey levels . the support that was given to the most important level , the vagina apex , was strong and sufficient ; therefore , this support indirectly helped reinforce the other levels . however , our measures did not show corresponding changes in the maximal anal resting pressure and squeeze pressure following anatomical repair , either with or without mesh . also reported that there is no relationship between preoperative manometry pressure changes and postoperative surgery outcome . taken together , these data suggest that there are factors other than structural changes that are involved in the development of pelvic floor dysfunction and may further suggest that the anorectal p might be a better index than resting and squeeze pressure for predicting the effects of posterior pelvic floor repair . repair with and without mesh both successfully cured pop , and no surgical failure was found in either group at the 3 months follow - up . furthermore , the pfiq-7 scores for both groups improved postoperatively , but only the nonmesh group showed a significant change ( p < 0.05 ) . these results indicate that as long as there is adequate apical / middle compartment support , posterior repair without mesh can achieve the same anatomic recovery as that of repair with mesh , along with better improvement in pelvic floor symptoms . moreover , repairs without the use of mesh avoid mesh - related complications and provide greater improvement in anorectal function . this is rarely mentioned in other reports , which simply note that these symptoms improve satisfactorily with the use of the prolift and prosima systems . one possible explanation for the difference we saw in anorectal function is that subjective symptom improvement does not necessarily mirror changes in objective parameter changes ; in addition , mesh exposure or erosion impairs bowel function recovery . one strength of this study was the use of an objective measure to assess the recovery of bowel function after pelvic floor reconstructive surgery , thus avoiding bias from subjective measures . the major drawbacks are the relatively small sample size and the relatively short follow - up time of 3 months . a larger sample size and/or randomized study with longer follow - up in addition , the two study groups were not the same size . despite the limitations , these objective anatomical and functional data will be useful for physicians to consider when counseling patients about the procedures used to treat posterior vaginal wall prolapse . in conclusion , as long as there is sufficient support for the anterior wall and apex of vagina with synthetic mesh , posterior vaginal compartment repair without mesh may be as effective as repair with mesh for anatomical recovery while providing better postoperative anorectal motor function and while avoiding mesh - related complications .
background : although repair augmented with mesh has been proved its priority in anatomical and functional recovery after anterior compartment reconstruction , the data about posterior compartment are scarce . the aim of this study was to compare bowel functional outcome of posterior vaginal compartment repair with and without mesh in patients with pelvic organ prolapse ( pop).methods : this was a prospective , double - blind , clinical pilot study of 22 postmenopausal women with symptomatic pop ( overall pop - quantification [ pop - q ] stage iii - iv ) who underwent total pelvic floor reconstruction . 
 patients were grouped according to the use of mesh for posterior vaginal compartment repair : a mesh group and a nonmesh group . 
 pop - q stage , the pelvic floor impact questionnaire short form-7 ( pfiq-7 ) and anorectal manometry were evaluated before and 3 months after surgery . 
 anatomical success was defined as pop - q stage ii or less . 
 a t - test was used to compare preoperative with postoperative data in the two groups.results:totally , 17 ( 71% ) were available for the follow - up . 
 pop - q measurements improved significantly compared to baseline ( p < 0.05 ) in both groups . no recurrence was observed . 
 subjects in both groups reported improvement in pelvic floor symptoms , and there was no significant difference in the pfiq-7 score between groups at follow - up ( p > 0.05 ) . compared with baseline , the nonmesh group exhibited a statistically significant decrease in anal residual pressure , a significant increase in the anorectal pressure difference during bowel movement , and a reduced rate of dyssynergia defecation pattern ( p < 0.05).conclusions : provided there is sufficient support for the anterior wall and apex of vagina with mesh , posterior compartment repair without mesh may be as effective as repair with mesh for anatomical recovery while providing better anorectal motor function .