Treatment Strategies for Urinary Sphincter Mechanism Incompetence

A large proportion of patients with urethral sphincter mechanism incompetence (USMI) responds to medical management and many dogs with ureteral ectopia complicated by USMI may require adjunctive medical management to become continent after ectopic ureteral repair. Estrogen therapy has also been investigated as a treatment for the USMI due the known association between spaying and USMI. A variety of surgical procedures have been described for treatment of the USMI in dogs when medical treatment failures occur. Open surgical options are primarily aimed at relocating the bladder neck and proximal urethra into the abdomen to expose the bladder neck and proximal urethra to increases in intraabdominal pressure or increasing the resistance to urine outflow in the urethra by direct pressure or constriction. The surgical procedures for female dogs are colposuspension, urethropexy and cystourethropexy, and male dogs are vas deferentopexy and prostatopexy.