Between 1976 and 1987, 22 children aged 3 to 17 years (mean age, 9.5 years) were admitted to our institution with major perineal trauma. There were 14 urethral ruptures and 9 rectal lesions. The lesions were multiple and combined: vaginal and urethral or vaginal and rectal injuries were found in 10 females, while only 1 of 12 males had both urethral and rectal lesions. In most instances, perineal physical signs did not reflect the severity of the lesion. Among the patients with urethral lesions, there was no sex or age predominance; complete rupture occurred in four females and eight males. The insertion of a urethral catheter was of no diagnostic help. Retrograde urethrogram demonstrated a lesion in seven of eight cases. The intravenous pyelogram (IVP) showed evidence of extravasation in two of the eight cases, and in four instances there were indirect rupture signs. A suprapubic cystostomy was performed in 12 of the 14 urethral injuries. A primary repair with urethral stenting was carried out twice without bladder drainage. Immediate repair was performed in eight cases and delayed in five others. Within this last group, two patients were cured without sequelae by stenting without suture, while the three others who underwent only cystostomy necessitated multiple reconstructive operations with poor results. It is of interest that the four treatment failures occurred in the youngest patients (4 to 7 years of age). The rectal lesions were related to impalement in seven of nine patients. Rectoscopy allowed localization of perforations but did not permit identification of sphincter injuries when the mucosa was intact. Primary repair was possible in all cases.(ABSTRACT TRUNCATED AT 250 WORDS)