Injuries to the bladder can be divided into blunt trauma (such as a blow to the body) or penetrating wounds (such as bullet or stab wounds). The nature of the injury to the bladder depends on the fullness of the bladder at the time of injury as well as the mechanism of the injury. Traumatic injury to the bladder is uncommon. Only about 8-10% of pelvic fractures are associated with bladder injury. Because the bladder is located within the bony structures of the pelvis, it is protected from most external forces. Injury may occur if there is a blow to the pelvis that is severe enough to break the bones and cause bone fragments to penetrate the bladder wall. Other causes of bladder injury include surgeries of the pelvis or groin, including hernia repair and abdominal hysterectomy. Injury to the urethra (the tube that carries urine out of the body) is slightly more common, especially in men. It is rare in women. Injury to the urethra includes cuts, tears, bruises, and similar injuries.
Injury to the bladder or urethra may cause urine to leak into the abdomen, leading to infection (peritonitis). This type of injury is more common if the bladder is full. There may be severe bleeding and loss of fluids. Scarring (stricture) or obstruction of the bladder or urethra from swelling may develop, leading to urinary stricture, obstruction, and retention. This may eventually cause vesicoureteric reflux or bilateral obstructive nephropathy (a type of kidney damage). There is an increased chance of developing urinary tract infections (UTI) after injury to the tissues of the urethra or bladder because of retained urine.
| 
