Stretched penile length in boys with hypospadias: Population-based analysis using validated nomogram.

Abstract

BACKGROUND: Hypospadias affects 1 in 200-300 male births. Parents are often concerned about penile adequacy beyond the urethral defect itself, yet few studies have systematically compared stretched penile length (SPL) in hypospadias against population-based reference standards. OBJECTIVE: To evaluate SPL distribution patterns in boys with Types I and II hypospadias and compare them with established normative data. METHODS: The authors studied 876 consecutive boys aged 1-14 years with unoperated Types I (distal) and II (mid-shaft) hypospadias. Two observers independently measured SPL using the validated SPLINT technique. The SPL measurements were compared against age-matched normative data from 1276 Indian children. Exact binomial probability tests were used for percentile distributions, chi-square tests for subtype comparisons and t-tests for mean deviations. RESULTS: The cohort included 479 Type I and 397 Type II cases. SPL distribution showed a marked leftward shift: 71% fell below the 50th percentile (expected 50%, p < 0.001) and 41.5% below the 25th percentile. Lower percentiles were overrepresented, 20.7% were below the 10th percentile and 20.8% in the 10th-25th range. Upper percentiles were depleted: only 7.4% in the 75th-90th range and 1.7% above the 90th percentile (all p < 0.001). Mean SPL was reduced by 6.8% (95% CI: -8.18 to -5.42%) in Type I and 7.5% (95% CI: -9.05 to -5.92%) in Type II. The two subtypes showed no significant distributional difference (&#x3c7;2 = 6.22, p = 0.18), suggesting that meatal position does not predict SPL reduction. CONCLUSIONS: Boys with distal and mid-shaft hypospadias show clinically meaningful SPL reduction that follows a continuous distribution rather than an all-or-none pattern. SPL reduction appears independent of meatal position. These findings support routine SPL assessment using population-specific references and can guide preoperative counselling.