[Effect of surgical steps in primary hypospadias repair on penile length]

To document the effect of surgical steps, including penile degloving, plate transection, dorsal plication, and fasciocutaneous coverage, in primary hypospadias repair on penile length.

A consecutive series of 209 prepubertal boys with primary hypospadias repair was included with the age ranged from 10 to 97 months (mean, 31.7 months). Intraoperative stretched penile length (SPL) was measured before operation ( n=209), and after each step, namely penile degloving ( n=152), plate transection ( n=139), dorsal plication ( n=170), and fasciocutaneous coverage ( n=209). SPLs before and after each steps or the entire operation were analyzed. The SPL was compared between plate transection group and plate preservation group, dorsal plication group and non-plication group, and plate preservation with plication group and plate preservation without plication group, respectively. Differences of SPL between before and after each steps were analyzed with factors including neourethra length, rest dorsal penile length, rest ventral penile length, preoperative SPL, and the degree of penile curvature after penile degloving, with multivariate linear regression analysis.

All the four steps resulted in SPL difference. The SPL increased after penile degloving and plate transection ( P<0.05), and decreased after dorsal plication and fasciocutaneous coverage ( P<0.05). The SPL increased after all steps were completed ( P<0.05). In patients with plate transection, postoperative SPL increased when compared with that before operation ( P<0.05). No significant difference was noted in patients without plate transection ( P>0.05). And there was significant difference in the increased length of SPL between patients with and without plate transection ( P<0.05). In patients with dorsal plication, a significant increase of postoperative SPL ( P<0.05) was noted. No significant difference was noted in patients without dorsal plication ( P>0.05). And there was no significant difference in increased length between patients with and without dorsal plication ( P>0.05). When patients with plate transection were excluded, dorsal plication resulted in no significant difference on postoperative SPL ( P>0.05). The increased length of SPL after penile degloving, dorsal plication, or cutanofascial coverage was not related to the neourethra length, the rest dorsal penile length, the rest ventral penile length, the preoperative SPL, and the degree of penile curvature ( P>0.05). However, the neourethra length and preoperative SPL were the influencing factors for the increased length of SPL after plate transection ( P<0.05).

The main steps in primary hypospadias repair can change SPL. The lengthening effect of plate transection would not be counteracted by dorsal plication. Dorsal plication makes no significant difference on postoperative SPL.