Outcomes of hypospadias reconstruction with buccal mucosal graft in children — a systematic review of randomized controlled trials and primary studies

Introduction

Buccal mucosal graft (BMG) is the dominant extragenital substitute for urethral reconstruction in severe, proximal and re-operative (“redo”) hypospadias, yet paediatric evidence remains fragmented across small single-centre series, and pooled estimates of its complication profile, its performance against preputial/skin and lingual grafts, and its durability through puberty are lacking. This review aimed to quantify surgical, functional, cosmetic and donor-site outcomes of BMG urethroplasty in children and to compare BMG with alternative substitutes.1–3 Methods: Following PRISMA 2020, primary studies published between January 2011 and September 2026 were identified using eight structured queries. Randomised controlled trials (RCTs), prospective and retrospective cohorts, case–control, cross-sectional and observational series of boys (≤18 years) undergoing BMG urethroplasty for hypospadias or its sequelae were eligible.4–7 Results: Twenty-six studies (4 RCTs, 8 comparative non-randomised studies, 14 non-comparative series; 2011–2025; 12 countries) were included, 23 of which contributed to meta-analysis. Across 1,080 BMG repairs (k = 20) the pooled composite adverse-outcome rate was 25.5% (95% CI 18.8–33.6) (I² = 83.3%; 95% prediction interval 6.1–64.4%), corresponding to a primary success rate of 74.5% (95% CI 66.4–81.2). Pooled rates were: urethrocutaneous fistula 8.4% (95% CI 6.2–11.4) (I² = 0%), meatal stenosis 8.1% (95% CI 3.6–17.2), urethral stricture 7.6% (95% CI 4.0–14.0) after excluding the tubularised-graft outlier, glans dehiscence 11.8% (95% CI 7.6–17.7), residual curvature 6.1% (95% CI 3.5–10.3), and unplanned re-intervention 14.8% (95% CI 8.3–24.9). Composite adverse outcomes were lowest after single-stage inlay/onlay BMG (16.8% (95% CI 9.9–27.1)), intermediate after staged Bracka repair (27.2% (95% CI 20.8–34.6)) and highest after free tubularised BMG (62.4% (95% CI 12.5–95.1)). Against preputial/skin grafts, BMG showed no significant difference in composite complications (RR 0.88 (95% CI 0.61–1.26); k = 5) or fistula (RR 1.07 (95% CI 0.37–3.09)), with a non-significant trend toward less meatal stenosis/stricture (RR 0.46 (95% CI 0.17–1.24)); BMG and lingual mucosal grafts performed equivalently (RR 1.01 (95% CI 0.46–2.23)). Persistent donor-site morbidity was rare (0/54). No small-study effect was detected (Egger p = 0.31). Certainty of evidence was low to very low.