Narrow urethral plate augmentation in anterior and middle hypospadias repair: Onlay flap VS. Inlay graft. A prospective randomized comparative study

Published:November 24, 2020DOI:



      The measurement of the urethral plate width (as an objective parameter) and its effect of this width on the results of tubularized incised plate urethroplasty (TIPU) have been reported in two series and both authors reported that a urethral plate width < 8 mm is associated with higher complication rates.
      The augmentation of the urethral plate either by dorsal inlay graft urethroplasty (DIGU) or Onlay flap has been compared with the original TIPU in different degrees of hypospadias with better surgical results in augmented cases.


      To evaluate the surgical results of longitudinal Onlay preputial flap (LOF) vs (DIGU) techniques in augmentation of the narrow urethral plate.

      Study design

      Primary anterior and middle hypospadias cases with narrow urethral plates were randomly allocated into two groups; group one operated by DIGU and group two operated by (LOF). The Success rate, individual complication rate, and operative times were compared.


      39 cases completed the study. No significant differences in patients' characteristics were detected.
      In the DIGU group, one case (5.3%) complicated with fistula and glandular dehiscence wherein in the LOF group, 7 cases (35%) Complicated with 5 fistulae, 2 glanular dehiscences, one flap loss, one diverticulum (p= .02). No significant differences in the rates of individual complications.


      Variables affecting the success of hypospadias repairs are many. Urethral plate quality is an important variable among these variables. The definition of urethral plate quality is usually subjective.
      In the DIGU group, only 1/19 (5.3%) case had two complications, fistula and glandular dehiscence. Mouravas et al., in their comparative study between TIPU and G-TIP without mention of urethral plate width reported a significant reduction of the overall complications and urethral stenosis without significant reduction in fistula rate. In their G-TIP group, only 2 cases out of 24 (8.3%) were complicated with one fistula and one glandular dehiscence where in the TIPU group, 7 cases (30.4%) were complicated with one glandular dehiscence and 6 cases with urethral stenosis.
      In the LOF group, fistula in 5/20 cases (25%) was the commonest complication followed by glandular dehiscence in 2 cases (10%). Diverticulum and flap loss occurred in one case for each (5%).
      In the multivariate analysis of 474 patients' cohort by Spinoit et al., there were no significant differences between the risk of re-intervention after TIP and Onlay flap in anterior and middle hypospadias (25.8% vs. 18.8%), and (22.2% vs. 20%) respectively.


      Summary Figure


      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Journal of Pediatric Urology
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Springer A.
        • Krois W.
        • Horcher E.
        Trends in hypospadias surgery: results of a worldwide survey.
        Eur Urol. 2011; 60: 1184-1189
        • Cook A.
        • Khoury A.E.
        • Neville C.
        • Bagili D.
        • Farhat W.
        • Pippi Salli J.
        • et al.
        A multicenter evaluation of technical preferences for primary hypospadias repair.
        J Urol. 2005; 174: 2354
        • Pfistermullera K.L.M.
        • McArdleb A.J.
        • Cuckow P.M.
        Meta-analysis of complication rates of the tubularized incised plate (TIP) repair.
        J Pediatr Urol. 2015; 11: 54-59
        • Holland A.J.
        • Smith G.H.
        • Ross F.I.
        • Cass D.T.
        HOSE: an objective scoring system for evaluating the results of hypospadias surgery.
        BJU Int. 2001; 88: 255-258
        • Sarhan O.
        • Saad M.
        • Helmy T.
        • Hafez A.
        Effect of suturing technique and urethral plate characteristics on complication rate following hypospadias repair: a prospective randomized study.
        J Urol. 2009; 182: 682-686
        • Bhat A.
        • Bhat M.
        • Kumar V.
        • Kumar R.
        • Mittal R.
        • Saksena G.
        Comparison of variables affecting the surgical outcomes of tubularized incised plate urethroplasty in adult and pediatric hypospadias.
        J Pediatr Urol. 2016; 12: 1-7
        • Mouravas V.
        • Filip popoulos A.
        • Sfoungaris D.
        Urethral plate grafting improves the results of tubularized incised plate urethroplasty in primary hypospadias.
        J Pediatr Urol. 2014; 10: 463-468
        • Gundeti M.
        • Queteishat A.
        • Desai D.
        • Cuckow P.
        Use of an inner preputial free graft to extend the indications of Snodgrass hypospadias repair (Snodgraft).
        J Pediatr Urol. 2005; 1: 395
        • Silay M.S.
        • Sirin H.
        • Tepeler A.
        • Karatag T.
        • Armagan A.
        • Horasanli K.
        • et al.
        “Snodgraft” technique for the treatment of primary distal hypospadias: pushing the envelope.
        J Urol. 2012 Sep; 188: 938-942
        • Braga L.
        • Pippi Salle J.
        • Lorenzo A.
        • Skeldon S.
        • Dave S.
        • Farhat W.
        • et al.
        Comparative analysis of tubularized incised plate versus onlay island flap urethroplasty for penoscrotal hypospadias.
        J Urol. 2007; 178: 1451-1457
        • Moradi M.
        • Moradi A.
        • Ghaderpanah F.
        Comparison of Snodgrass and Mathieu surgical techniques in anterior distal shaft hypospadias repair.
        Urol J. 2005; 2: 28-31
        • Snodgrass W.
        • Cost N.
        • Nakonezny P.
        • Bush N.
        Analysis of risk factors for glans dehiscence after tubularized incised plate hypospadias repair.
        J Urol. 2011; 185: 1845-1851
        • Bush N.C.
        • Snodgrass W.
        Pre-incision urethral plate width does not impact short-term tubularized incised plate urethroplasty outcomes.
        J Pediatr Urol. 2017; 13 (e1e6): 625
        • Weber D.M.
        • Schonbucher V.B.
        • Landolt M.A.
        • Gobet R.
        The Pediatric Penile Perception Score: an instrument for patient self-assessment and surgeon evaluation after hypospadias repair.
        J Urol. 2008; 180: 1080
        • Ozturka H.
        • Onena A.
        • Otcu S.
        • Kaya M.
        • Ozturk H.
        The outcome of one-stage hypospadias repairs.
        J Pediatr Urol. 2005; 1: 261-266
        • Shimotakahara A.
        • Nakazawa N.
        • Wada A.
        • Nagata S.
        • Koga H.
        • Takahashi T.
        • et al.
        Tubularized incised plate urethroplasty with dorsal inlay graft prevents meatal/neourethral stenosis: a single surgeon's experience.
        J Pediatr Surg. 2011; 46: 2370-2372
        • Snodgrass W.
        • Macedo A.
        • Hoebeke P.
        • Mouriquand P.D.
        Hypospadias dilemmas: a round table.
        J Pediatr Urol. 2011; 7: 145-157
        • Nguyen M.T.
        • Snodgrass W.T.
        • Zaontz M.R.
        Effect of urethral plate characteristics on tubularized incised plate urethroplasty.
        J Urol. 2004; 171: 1260-1262
        • Helmy T.E.
        • Ghanem W.
        • Orban H.
        • Omar H.
        • El-Kenawy M.
        • Hafez A.T.
        • et al.
        Does grafted tubularized incided plate improve the outcome after repair of primary distal hypospadias: a prospective randomized study?.
        J Pediatr Surg. 2018; 53: 1461-1463
      1. Seleim HM, El Sheemy MS, Abdalazeem YY, Abdullateef KS, Arafa MA, Shouman AM, et al. Comprehensive evaluation of grafting the preservable narrow plates with consideration of native plate width at primary hypospadias surgery. J Pediatr Urol.

        • Kolon T.F.
        • Gonzales E.T.
        The dorsal inlay graft for hypospadias repair.
        J Urol. 2000; 163: 1941
        • Ferro F.
        • Vallasciani S.
        • Borsellino A.
        • Atzori P.
        • Martini L.
        Snodgrass urethroplasty: grafting the incised plate–10 years later.
        J Urol. 2009; 182: 1730-1734
        • Asanuma H.
        • Satoh H.
        • Shishido S.
        Dorsal inlay graft urethroplasty for primary hypospadiac repair.
        Int J Urol. 2007; 14: 43-47
        • Gupta Vipul
        • Yadav Sunil Kumar
        • Alanzi Talal
        • Islam Amer
        • Salah Mohmmad
        • Ahmed Mamdouh
        Grafted tubularised incised-plate urethroplasty: an objective assessment of outcome with lessons learnt from surgical experience with 263 cases.
        Arab J Urol. 2016 Dec; 14: 299-304
        • Spinoit A.F.
        • Poelaert F.
        • Van Praet C.
        • Groen L.A.
        • Van Laecke E.
        • Hoebeke P.
        Grade of hypospadias is the only factor predicting for re-intervention after primary hypospadias repair: a multivariate analysis from a cohort of 474 patients.
        J Pediatr Urol. 2015; 11: 70 1-6
        • Elder J.S.
        • Duckett J.W.
        • Snyder H.M.
        Onlay island flap in the repair of mid and distal penile hypospadias without chordee.
        J Urol. 1987; 138: 376
        • Baskin L.S.
        • Duckett J.W.
        • Ueoka K.
        • Seibold H.
        • Snyder M.H.
        Changing concepts of hypospadias curvature lead to more onlay island flap procedures.
        J Urol. 1994; 151: 191
        • Shuzhu C.
        • Min W.
        • Yidong L.
        • Weijing Y.
        Selecting the right method for hypospadias repair to achieve optimal results for the primary situation.
        SpringerPlus. 2016; 5: 1624
        • Xu N.
        • Xue X.Y.
        • Li X.D.
        • Wei Y.
        • Zheng Q.S.
        • Jiang T.
        Comparative outcomes of the tubularized incised plate and transverse island flap onlay techniques for the repair of proximal hypospadias.
        Int Urol Nephrol. 2014; 46: 487-491
        • Castagnetti M.
        • Zhapa E.
        • Rigamonti W.
        Primary severe hypospadias: comparison of reoperation rates and parental perception of urinary symptoms and cosmetic outcomes among 4 repairs.
        J Urol. 2013; 189: 1508-1513

      Linked Article