Importance of urethral length, bladder neck position and vestibulovaginal stenosis in sphincter mechanism incompetence in the incontinent bitch.

The urethral length, bladder neck position and presence of vestibulovaginal stenosis were recorded in 42 continent bitches and 57 incontinent bitches diagnosed as having sphincter mechanism incompetence. Incontinent animals had significantly shorter urethras and tended to have intrapelvic rather than intraabdominal bladder necks. There was no statistical difference in the incidence of vestibulovaginal stenosis between continent and incontinent bitches.