A New Suture Material for Hypospadias Surgery: A Comparative Study

Retrospective Comparative Study between Duplay and Koff Methods in Repair of Distal Hypospadias

BACKGROUND

Hypospadias repair is a complicated surgery even in the best of hands. To date, there is a lack of consensus on which surgical technique offers more favourable post-operative outcomes. The present work was undertaken to evaluate and compare the outcomes and complications rates of two single-stage techniques widely used to repair primary anterior hypospadias, namely Thiersch-Duplay Tubularized Plate Urethroplasty and Koff Urethral Mobilisation and Advancement.

MATERIALS AND METHODS

Data from the medical records of 120 patients operated on for primary anterior hypospadias were retrospectively analysed and compared. The patients were divided into two groups: 60 patients underwent Thiersch-Duplay procedure (Group A) and 60 patients underwent Koff procedure (Group B). They were compared using the Chi-squared or Fisher's exact test to assess the relationship between the adopted surgical technique and the complications' development with a P < 0.05.

RESULTS

Neither intraoperative complications nor acute post-operative complications occurred, whereas 28.3% ( n = 34/120) cases have exhibited at least one late post-operative surgical complication, including 38.3% ( n = 23/60) in Group A and 18.3% ( n = 11/60) in Group B, revealing a better outcome of the Koff procedure despite the statistical insignificance ( P = 0.102). We did not objectify any other complication besides meatal stenosis (MS), urethro-cutaneous fistula (UCF) and wound dehiscence.

CONCLUSION

Overall, our study could not demonstrate the superiority of one technique above another. At the same time, it established the versatility, satisfactory cosmetic and functional results, low MS and UCF rates of Koff urethral mobilization and advancement technique in primary anterior hypospadias repair.

Post-urethroplasty complications in hypospadias repair: a systematic review and meta-analysis comparing polydioxanone and polyglactin sutures

Background

Polyglactin (PG) and polydioxanone (PDS) sutures are extensively used based on the surgeon's preference. The development of post-reconstruction urethrocutaneous fistula (UCF) is variably attributed to the choice of suture material for urethroplasty. This meta-analysis compares complications of hypospadias repair using PG and PDS sutures.

Methods

The systematic review and meta-analysis were performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. The authors conducted thorough searches in databases including MEDLINE, EMBASE, CENTRAL, Scopus, Google Scholar, and clinical trial registries. Outcome measures included UCF, meatal stenosis, wound infection, urethral stricture, glans dehiscence, and overall complications. Quantitative analysis was used with fixed or random-effect models to find the pooled risk ratio and I2 heterogeneity.

Results

The criteria for inclusion were met by five comparative studies with the inclusion of 1244 children altogether. Pooled analysis failed to show a statistically significant difference in the incidence of meatal stenosis, urethral stricture, wound infection, and total complications using PG and PDS sutures. However, it showed a reduction in the incidence of UCF with PDS suture hypospadias repairs (risk ratio=0.66, 95% CI 0.48 to 0.92).

Conclusions

PDS sutures are associated with decreased incidence of UCF than PG after hypospadias repair. The incidence of meatal stenosis, urethral stricture, wound infection, and total complications was not affected by the type of suture material used for repair.

Clinical implications

This meta-analysis suggests decreased incidence of UCF when PDS sutures are used for hypospadias repair which may impact the choice of suture material for repair.

PROSPERO registration number

CRD42023409710.

Comparison of post-urethroplasty complication rates in pediatric cases with hypospadias using Vicryl or polydioxanone sutures

Objective

Hypospadias is a common congenital problem among male newborns. Both rapid absorbable sutures (polyglactin, Vicryl) and delayed absorbable sutures (polydioxanone, PDO) are used in hypospadias repair based on the surgeon's preference. This study was conducted to compare post-urethroplasty complication rates in pediatric patients with hypospadias using Vicryl or PDO sutures.

Methods

This is a retrospective study which was designed and performed on 583 children aged 1–7 years old who had undergone hypospadias repair from January 2012 to December 2018. Required data were obtained from the patients' medical records.

Results

Overall, post-surgical complications were observed in 60 (10.3%) patients comprising urethro-cutaneous fistula (n=39, 6.7%), meatal stenosis (n=10, 1.7%), urethral stricture (n=7, 1.2%), and glans dehiscence (n=4, 0.7%). The mean age of the children with complications was 3.0±1.3 years. According to Kaplan-Meier estimate, the interval between surgery and development of complications was significantly shorter in the Vicryl group (p=0.037). Overall, complications were more prevalent in Vicryl suture than PDO suture (15.1% vs. 5.3%, p<0.001). Regression model revealed that in comparison to the distal type, proximal hypospadias (odds ratio [OR]:103.9, 95% confidence interval [CI]: 32.2–334.9, p<0.001) and mid-shaft hypospadias (OR: 82.9, 95% CI: 25.9–264.6, p<0.001) while using Vicryl suture instead of PDO suture (OR: 62.4, 95% CI: 21.2–183.8, p<0.001) increased the odds of developing post-urethroplasty complications.

Conclusion

We suggest PDO suture in the repair of hypospadias due to its lower complication rate, especially in cases of proximal and mid-shaft hypospadias which can get more complicated than the distal type.

Association between intra-operative meatal mismatch and urethrocutaneous fistula development in hypospadias repair

INTRODUCTION

The Glans-Meatus-Shaft (GMS) Score is a pre-operative phenotypic scoring system used to assess hypospadias severity and risk for post-operative complications. The 'M' component is based on pre-operative meatal location, but meatal location sometimes changes after penile degloving, resulting in 'meatal mismatch.'

OBJECTIVE

To identify: 1) the incidence and clinical predictors of meatal mismatch, and 2) the association of meatal mismatch with post-operative urethrocutaneous fistula development.

STUDY DESIGN

We performed a retrospective cohort study on patients who underwent primary hypospadias repair at a single center from 2011 to 2018. Meatal mismatch was defined as: upstaging (meatus moving more proximally after degloving), downstaging (moving more distally after degloving), or none. Covariates included: pre-degloving meatal location, chordee severity, penoscrotal anatomy, pre-operative testosterone, and number of stages for repair. To test the association between meatal mismatch and fistula development, we constructed two, nested, multivariable Cox proportional hazards regression models with and without meatal mismatch and compared them with the likelihood ratio test. A sensitivity analysis excluded patients with <6 months of follow-up.

RESULTS

Of 485 patients, 99 (20%) exhibited meatal mismatch, including 75 (15%) with upstaging and 24 (5%) patients with downstaging (Figure). Meatal mismatch was significantly associated with penoscrotal webbing, number of stages for repair, and pre-degloving meatal location, with downstaging being associated with more proximal meatal location. Over a median follow-up of 7.3 months (interquartile range 2.0-20.9), fistulae developed in 56 (12%) patients. On multivariable analysis, meatal upstaging was associated with a 3-fold increased risk of fistula development (Hazards Ratio [HR]: 3.04, 95% Confidence Interval [CI]: 1.44-6.45) compared to no mismatch. Meatal downstaging had similar risk of fistula development compared to no mismatch (HR: 0.99, 95% CI: 0.29-3.35). Multi-stage compared to single-stage repair was associated with reduced risk of fistula development (HR: 0.24, 95% CI: 0.09-0.66). The likelihood ratio test favored the model that included meatal mismatch. The sensitivity analysis showed similar findings.

DISCUSSION

Our short-term results suggest that meatal mismatch may be an important additional consideration to the GMS score as a tool to assess hypospadias severity, counsel families, and predict outcomes. Longer-term studies are needed to enhance the precision of risk stratification in hypospadias.

CONCLUSIONS

Meatal mismatch occurred in 20% of patients undergoing hypospadias repair. Among this cohort, meatal upstaging was associated with a 3-fold increased risk of post-operative urethrocutaneous fistula development.

Complications Following Primary Repair of Non-proximal Hypospadias in Children: A Systematic Review and Meta-Analysis

Purpose: The aim of this study was to systematically review the literature on the complications and postoperative outcomes of children with non-proximal hypospadias. Methods: Electronic databases including PubMed, Embase, and Cochrane Library CENTRAL were searched systematically from January 1990 to June 2020 for the literature that reported the postoperative outcomes of patients with non-proximal hypospadias. Non-proximal hypospadias encompassed distal and mid-penile hypospadias. Results: We included 44 studies involving 10,666 subjects. Urethrocutaneous fistula (UCF) was the most common complication with an incidence of 4.0% (95% CI, 3.1-5.0%). Incidence of overall complications was 8.0% (95% CI, 6.3-9.8%). Meta-regression analysis revealed that length of urethral stent indwelling (coefficient 0.006; 95% CI, 0.000-0.011; p = 0.036) and penile dressing (coefficient 0.010; 95% CI, 0.000-0.021; p = 0.048) were two risk factors for UCF. Multivariate meta-regression analysis did not identify any independent risk factors for UCF. No differences were found between stent and stentless groups in non-proximal hypospadias regarding incidences of UCF (OR, 0.589; 95% CI, 0.267-1.297), meatal stenosis (OR, 0.880; 95% CI, 0.318-2.437), and overall complications (OR, 0.695; 95% CI, 0.403-1.199). No differences were found between foreskin preservation and circumcision in terms of complications either. Conclusions: UCF is the most common complication following hypospadias repair with an incidence of 4.0%. Independent risk factors for UCF were not identified in the current research. Distal hypospadias repair without stent indwelling is not likely to compromise the postoperative outcome. Further studies should be designed to explore the differences between different surgical approaches and the potential risk factors for complications following hypospadias repair.

In Vivo Comparison of "V-Loc 90 Wound Closure Device" With "Vicryl" and "Monocryl" in Regard to Tissue Reaction in a Rabbit Bladder Model

OBJECTIVE

To compare the barbed polyglyconate suture (BPS) with 2 commonly used conventional sutures, this prospective randomized trial was designed. The sutures applied in the urinary collecting system, in terms of long-term histopathologic and macroscopic suture material features.

MATERIALS AND METHODS

Eight female and 6 male New Zealand rabbits were included in the study. Each animal served as its own control and was subjected to cystotomy. Watertight running cystorrhaphies were performed using 3 different sutures in a randomized fashion, namely Monocryl, Vicryl, and V-Loc 90. Seven animals were sacrificed after the third and 7 after the sixth week. Macroscopic and histopathologic examinations were performed. Tissue reaction, like inflammation and fibrosis, around the sutures were evaluated. Friedman and Wilcoxon signed ranks test was used for the statistical analysis.

RESULTS

The BPS demonstrated no adhesion. However, in the six-week group, stone formation was recorded on 4 BPS and 1 Vicryl thread, a difference being statistically significant (P = .039). Additionally, in the third- and in the sixth-week group, 1 (P = .368) and 3 (P = .050) BPS threads migrated, respectively. The histopathologic analysis revealed less inflammation and fibrosis associated with the BPS thread in both the third and the sixth-week groups (P = .010 and P = .002, respectively).

CONCLUSION

The BPS appears to be superior to conventional sutures in terms of local inflammation and fibrosis. However, suture migration and stone formation following collecting system closure could be potential predicaments.

Application of the STROBE statement to the hypospadias literature: Report of the international pediatric urology task force on hypospadias

INTRODUCTION

Observational studies, particularly case series, represent the majority of the current hypospadias research. As a result, this literature lacks standardization of surgical techniques, uniform definitions of hypospadias complications, and consistency of outcome reporting, which may make it difficult to compare results across studies. A modified version of the STROBE statement, containing 20 items, was presented at the International Pediatric Urology Task Force on Hypospadias meeting to assist with clear and transparent reporting of hypospadias studies. The adoption and implementation of this modified tool will allow investigators and health care providers to critically evaluate quality and identify bias within the literature. In addition this instrument will ensure consistency of reporting, improving objective comparisons between studies, unification of results, and development of evidence-based clinical guidelines.

METHODS

In this article, we have applied the modified STROBE statement to the hypospadias literature, aiming to create a guide on study reporting for pediatric urologists, and ultimately improve the quality of research in our field. We present itemized recommendations for adequate reporting of hypospadias studies and case series, ranging from drafting the abstract to addressing biases and potential sources of confounding. Included with each item is a brief explanation of its importance and potential effect on the study, as well as pertinent examples of hypospadias articles.

RESULTS

A modified STROBE summary table containing 20 items is presented in (Supplementary Table 1).

CONCLUSIONS

If properly conducted and reported, hypospadias studies have the potential to provide useful information to clinicians and surgeons. However, authors should recognize the inherent limitations of these observational studies, especially in the form of bias, which may introduce invalid data or limit generalizability. Thus, we expect that the use of this guiding tool will not only improve transparency of hypospadias reporting, but also improve its methodological quality, allowing proper comparison and interpretation of data across different institutions.

Grade of hypospadias is the only factor predicting for re-intervention after primary hypospadias repair: a multivariate analysis from a cohort of 474 patients

BACKGROUND

There is an ongoing quest on how to minimize complications in hypospadias surgery. There is however a lack of high-quality data on the following parameters that might influence the outcome of primary hypospadias repair: age at initial surgery, the type of suture material, the initial technique, and the type of hypospadias.

OBJECTIVES

The objective of this study was to identify independent predictors for re-intervention in primary hypospadias repair.

STUDY DESIGN

We retrospectively analyzed our database of 474 children undergoing primary hypospadias surgery. Univariate and multivariate logistic regression was performed to identify variables associated with re-intervention. A p-value <0.05 was considered statistically significant and therefore considered as a prognostic factor for re-intervention.

RESULTS

Distal penile hypospadias was reported in 77.2% (n = 366), midpenile in 11.4% (n = 54) and proximal in 11.4% (n = 54) of children. Initial repair was based on an incised plate technique in 39.9% (n = 189), meatal advancement in 36.0% (n = 171), an onlay flap in 17.3% (n = 82) and other or combined techniques in 5.3% (n = 25). In 114 patients (24.1%) re-intervention was required (n = 114) of which 54 re-interventions (47.4%) were performed within the first year post-surgery, 17 (14.9%) in the second year and 43 (37.7%) later than 2 years after initial surgery. The reason for the first re-intervention was fistula in 52 patients (46.4%), meatal stenosis in 32 (28.6%), cosmesis in 35 (31.3%) and other in 14 (12.5%). The median time for re-intervention was 14 months after surgery [range 0-114]. Significant predictors for re-intervention on univariate logistic regression (polyglactin suture material versus poliglecaprone, proximal hypospadias, lower age at operation and other than meatal advancement repair) were put in a multivariate logistic regression model. Of all significant variables, only proximal hypospadias remained an independent predictor for re-intervention (OR 3.27; p = 0.012).

DISCUSSION

The grade of hypospadias remains according to our retrospective analysis the only objective independent predicting factor for re-intervention in hypospadias surgery. This finding is rather obvious for everyone operating hypospadias. Curiously midpenile hypospadias cases were doing slightly better than distal hypospadias in terms of re-intervention rates. Our study however has also some shortcomings. First of all, data was gathered retrospectively and follow-up time was ill-balanced for several variables. We tried to correct this by applying sensitivity analysis, but possible associations between some variables and re-intervention might still be obscured by this. Standard questionnaires to analyze surgical outcome were not available. Therefore, we focused our analysis on re-intervention rate as this is a hard and clinically relevant end point.

CONCLUSIONS

This retrospective analysis of a large hypospadias database with long-term follow-up indicates that the long-lasting debate about factors influencing the reoperation rate in hypospadias surgery might be futile: in experienced hands, the only variable that independently predicts for re-intervention is the severity of hypospadias, the only factor we cannot modify. This retrospective multivariate analysis of a large hypospadias database with long-term follow-up suggests that the only significant independent predictive factor for re-intervention is proximal hypospadias. In our series, technique did not influence the re-intervention rate.

Recent advances in understanding/management of hypospadias

Hypospadias is the second most common birth anomaly, affecting 1 of every 300 males. The abnormal position of the urinary opening, and associated downward curvature of the penis in some cases, potentially impact both urinary and sexual function. Modern surgical correction most often involves tubularization of the urethral plate, those tissues which normally should have completed urethral development. This article discusses recent progress in hypospadias repair. Prospective data collection in consecutive patients promotes better understanding of both patient and technical factors that influence surgical complications. Patients with a proximal urinary opening near or within the scrotum, those failing prior to repairs, and/or those with a small glans diameter have increased likelihood for urethroplasty complications. Quality review of reliable data led to two layer urethroplasty covered with tunica vaginalis in proximal repairs, significantly reducing postoperative fistulas. Neither preoperative androgens used to grow a small diameter glans, nor a change in sutures used to approximate the glans wings reduced wound dehiscence, but a recent technical modification of the glansplasty with more extensive dissection before suturing has. The observation that reoperation increases risk for further complications three-fold suggests the less common proximal repairs and reoperations should be subspecialized so that designated surgeons can gain greater expertise. In addition, surgeons performing hypospadias repair must better define the complications that occur so that scientific reporting of outcomes becomes more standardized. Standardized objective means to assess results are also needed so that surgeons performing different repairs can compare outcomes.

Failed hypospadias in paediatric patients

Failed hypospadias refers to any hypospadias repair that leads to complications or causes patient dissatisfaction. The complication rate after hypospadias repairs ranges from 5-70%, but the actual incidence of failed hypospadias is unknown as complications can become apparent many years after surgery and series with lifelong follow-up data do not exist. Moreover, little is known about uncomplicated repairs that fail in terms of patient satisfaction. Risk factors for complications include factors related to the hypospadias (severity of the condition and characteristics of the urethral plate), the patient (age at surgery, endocrine environment, and wound healing impairment), the surgeon (technique selection and surgeon expertise), and the procedure (technical details and postoperative management). The most important factors for preventing complications are surgeon expertise (number of cases treated per year), interposition of a barrier layer between the urethroplasty and the skin, and postoperative urinary drainage. Major complications associated with failed hypospadias include residual curvature, healing complications (preputial dehiscence, glans dehiscence, fistula formation, and urethral breakdown), urethral obstruction (meatal stenosis, urethral stricture, and functional obstruction), urethral diverticula, hairy urethra, and penile skin deficiency.

Effect of human urine on the tensile strength of sutures used for hypospadias surgery

INTRODUCTION

Hypospadias is the most common congenital condition affecting between 1 in 250 and 300 live births. Even in experienced hands, surgery to repair this congenital defect can have a high complication rate. Wound dehiscence is reported to occur in 5% and fistula formation in 6%-40% depending on technique. The choice of suture material has been shown to affect the complication rate although there is (currently) no consensus about the best suture material to use. Ideally, the sutures used for urethroplasty should be absorbable while maintaining sufficient mechanical strength to support the wounds until they are self-supporting and able to resist urinary flow. Previous studies have compared the effects of human urine on different suture materials especially catgut. However, catgut is now banned in Europe. Our study examined the tensile and breaking strength as well as rate of degradation for four types of absorbable suture now commonly used for hypospadias repairs in the UK.

MATERIAL AND METHODS

We examined the effect of prolonged storage (up to 27 days) in human urine on 6/0 gauge Vicryl, Vicryl Rapide, Monocryl and polydioxanone (PDS) sutures. These four suture materials are commonly used by the senior plastic consultant surgeon (NK) for hypospadias repairs. 50 mm sections of these suture materials were stored in either urine or saline as control. At specified time points, each suture was placed in a uniaxial load testing machine to assess the stress-strain profile and the mechanical load required to break the suture was measured.

KEY RESULTS

Exposure to urine reduced the tensile and breaking strength of all the suture materials tested. PDS demonstrated the greatest resilience. Vicryl Rapide was the weakest suture and degraded completely by day 6. Vicryl and Monocryl had similar degradation profiles, but Vicryl retained more of its tensile strength for longer.

CONCLUSIONS

There is a balance to be struck between the duration that a suture material must remain in any surgical wound and the risk that it causes foreign body effects. The results of this study suggest that Vicryl has the best characteristics for urethroplasty of the four suture materials tested.

Hypospadias surgery past, present and future

PURPOSE OF REVIEW

Hypospadias surgery has been in continuous evolution for many years with steadily improving reported results. Despite this many unanswered questions on its cause, management and outcomes remain. Recent research has done little to clarify most matters.

RECENT FINDINGS

There is increasing evidence of a balance of genetic and developmental factors in the development of hypospadias, but there is doubt whether the incidence of hypospadias is increasing or not. Many technical aspects of hypospadias repair and variations of perioperative management seem to have little effect on outcome, whereas the age at which surgery is performed may. Although efforts are being made to relate anatomical findings to outcome, a lack of objective assessment and standardization is a handicap. Severe hypospadias, particularly that associated with significant chordee, remains challenging although strategies for management are being developed. The future may lie in development of autologous tissue culture for these severe cases.

SUMMARY

Further development of hypospadias surgery would benefit from objective, standardized methods of describing anatomy and outcome measures to facilitate effective comparison of techniques and procedures.

Review Paper: Absorbable Polymeric Surgical Sutures: Chemistry, Production, Properties, Biodegradability, and Performance

Among biomaterials used as implants in human body, sutures constitute the largest groups of materials having a huge market exceeding $1.3 billion annually. Sutures are the most widely used materials in wound closure and have been in use for many centuries. With the development of the synthetic absorbable polymer, poly(glycolic acid) (PGA) in the early 1970s, a new chapter has opened on absorbable polymeric sutures that got unprecedented commercial successes. Although several comparative evaluations of suture materials have been published, there were no serious attempts of late on a comprehensive review of production, properties, biodegradability, and performance of suture materials. This review proposes to bring to focus scattered data on chemistry, properties, biodegradability, and performance of absorbable polymeric sutures.