0022-534 7/79/1214-0455$2.00/0 THE JOURNAL OF UROLOGY
Vol. 121, April
Copyright © 1979 by The Williams & Wilkins Co.
Printed in U.S.A.
UROLOGICAL INJURIES ASSOCIATED WITH PELVIC TRAUMA MILTON POKORNY, J. EDSON PONTES
AND
JAMES M. PIERCE, JR.
From the Department of Urology, Wayne State University School of Medicine and Detroit General Hospital Research Corporation, Detroit, Michigan
ABSTRACT
We reviewed 100 consecutive cases of pelvic fractures at our hospital to establish the relationship between bone injuries and urological lesions. There were 11 major urological injuries found: 6 patients had bladder laceration, 4 had rupture of the membranous urethra and 1 had a ureteral injury. Emphasis is placed on the physiopathology of the urological injuries. Frequently in the medical literature emphasis is placed on statistical reviews of certain subjects, such as numbers of 'urological injuries, while the pathologic mechanism of these entities is relegated to a secondary plan. This attitude leads to a poor understanding of the factors responsible for a certain pathology and a superficial view of the problems involved. Our study was done in an attempt to postulate the relationship between pelvic fractures and urological injuries. MATERIAL
A detailed review was made of 100 cases of major pelvic fractures seen at our hospital within the last 2112 years. The records of each patient were evaluated as to age, sex, cause of injury, type of fracture, and urological symptoms and signs. Urological diagnostic evaluation was done on every patient as described previously. 1 The radiographic records of each patient were evaluated to determine the type of injury and its possible relationship to the urinary tract involvement. RESULTS
Among the 100 patients there were 62 male and 38 female subjects, ranging in age from 13 to 80 years. Automobile accidents were responsible for 68 per cent of the injuries. Hematuria was present in 66 per cent of the patients and it was microscopic in 66 per cent of these. Two patients were seen for urinary retention after the fractures, 1 of whom underwent prostatectomy 6 months later. Further evaluation of the pelvic fractures revealed that 71 patients had fractures involving the pubic bone and 20 of these patients had both pubic bones fractured. Of particular interest are the unstable fractures of the pelvis caused by disruption of the anterior and posterior aspect of the pelvic ring, which are referred to as diametric2 or Malgaigne's fracture. This type of injury was seen in 14 patients and in 6 of these patients the displacement of the hemipelvis was owing to rupture of the sacroiliac joint and pubic symphysis without bone fracture (fig. 1). Diastasis of the pubic bones without any fracture was seen in 3 patients, none of whom had urological injuries. Associated injuries included fractures elsewhere in 42 patients, liver injuries in 2, rupture of the gallbladder in 1, laceration of mesenteric vessels in 1, head injuries in 7, rupture of the diaphragm in 1, rupture of the spleen in 2 and rupture of the right main bronchus in 1. Three patients died of the severity of the trauma before complete evaluation could be done. Among the 100 patients we found 11 major urological injuries in 10 patients. These included 6 ruptures of the bladder, 4 ruptures of the posterior urethra and 1 ureteral injury. One female subject had bladder and urethral lacerations owing to a comminuted pubic fracture. Accepted for publication July 28, 1978. 455
MECHANISM OF INJURY
Bladder injury. The probability of bladder injury is related to its distension. An empty bladder will be injured seldomly. Anatomically, bladder ruptures are either intraperitoneal or extraperitoneal. Of the 6 patients with rupture of the bladder 4 had intraperitoneal and 2 had extraperitoneal ruptures. The mechanism responsible for each type of injury is quite different. A full bladder frequently is involved in intraperitoneal ruptures. A sudden increase of pressure leads to rupture of the least supported surface of the bladder, the dome, with resulting intraperitoneal extravasation (fig. 2, A). Although this is the most common mechanism we postulate that a high fracture of the pelvic ring also could lead to a bladder rupture secondary to a bone fragment. The extent of pelvic fracture in intraperitoneal ruptures varied from a small fracture without displacement to a complex fracture. One patient had an intraperitoneal rupture associated with diastasis of the pubis and a fracture of the pubic rami. We believe that the common link among all of these patients was a full bladder. Extraperitoneal ruptures of the bladder in pelvic fractures commonly are associated with fracture of the pubis. Because of its close anatomical relationship a bony spicule often perforates the bladder. Another mechanism causing rupture is stress over the hypogastric wing and/or puboprostatic ligament and, finally, to the bladder wall. 3- 5 This occurs in diastasis of the pubis, associated or not with a diametric fracture. In 1 case the diastasis was accomplished by a comminuted fracture of the pubic rami with the possibility that a bony spicule was responsible for rupture at the bladder neck (fig. 2, B). Urethral injury. There are 4 mechanisms responsible for injury of the posterior urethra in pelvic trauma. The most common situation occurs in a diametric fracture when there is displacement of the hemipelvis upward, exerting traction on the hypogastric wing attached to the base of the bladder and prostate. 6 This upward displacement of the symphysis leads to the rupture of the puboprostatic ligament and stretching of the prostatomembranous urethra to the point of rupture. The bulbous urethra is not involved in the injury because it is fixed to the corpus spongiosum and central tendon. This type of fracture often is caused by a force acting over the ipsilateral femur. Of our patients 2 with rupture of the prostatomembranous urethra had this type offracture (fig. 3). Diametric fracture alone, without urological injury, was found in 10 additional patients, in some of whom stretching of the membranous urethra was noted without rupture. The second mechanism postulated occurs in bilateral fracture of the superior and inferior pubic rami. The fractured segment is displaced postero-inferiorly owing to a force acting over the pubis (fig. 4). We postulate that the sudden retrocession of the urogenital diaphragm against the membranous
Fm. 2 Origin of hypogastric artery
Fm. 3 456
UROLOGICAL INJURIES ASSOCIATED WITH PELVIC TRAUMA
457
G) Fm. 4
Fm. 5
urethra acts as a guillotine causing the urethral injury. One patient in this series had this type of injury (fig. 5). The third mechanism involves diastasis of the symphysis pubis with rupture of 1 puboprostatic ligament and tearing of the urogenital diaphragm from the contralateral bone. During the diastasis the membranous urethra will be pulled in 2 directions opposite to the point ofrupture. 7 The fourth mechanism proposed involves direct injury of the posterior urethra by a bony spicule during fractures of the pubis close to the midline. Ureteral injury. Rupture of the lower third of the ureter in blunt trauma is rare. A patient with multiple pelvic fractures and a partial laceration of the right ureter was encountered in this series. We postulate that the injury was caused most likely by a bony spicule after fracture of the right acetabulum. COMMENTS
Although the final picture seen on radiological examination does not reflect the dynamic forces at the time of injury we attempted to correlate the types of pelvic fractures most likely associated with urological injuries. Proper urological evaluation is necessary in order to decide the extent of injury and management. Although all of our 10 patients with major injury had gross hematuria we believe that all patients with hematuria, either gross or microscopic, need complete evaluation. Injuries of the bladder are often the result of forces acting upon a full bladder causing intraperitoneal rupture.
Extraperitoneal ruptures of the bladder are caused either by the direct impact of a bony spicule or by forces applied to anatomical ligaments of the bladder. Urethral injuries are the most serious complication of pelvic fractures. Mechanisms described to explain those ruptures include diametric fracture, bilateral fracture of the pubic rami with guillotine-like action at the membranous urethra, diastasis of the symphysis pubis with rupture of 1 puboprostatic ligament and direct injury owing to a bony spicule. REFERENCES
1. Pontes, J. E.: Urologic injuries. Surg. Clin. N. Amer., 57: 77,
1977. 2. Trunkey, D. D., Chapman, M. W., Lim, R. C., Jr. and Dunphy, J.E.: Management of pelvic fractures in blunt trauma injury. J. Trauma, 14: 912, 1974. 3. Monfort, J., Bainverl, J. V., Auvigne, J. and Buzelin, J.M.: Les complications urinaires immediates au cours des disjonctions de la symphyse pubienne. J. Urol. Nephrol., 79: 245, 1974. 4. Morehouse, D. D. and MacKinnon, K. J.: Urological injuries associated with pelvic fractures. J. Trauma, 9: 479, 1969. 5. Prather, G. C. and Kaiser, T. F.: The bladder in fracture of bony pelvis; the significance of a "tear drop bladder" as shown by cystogram. J. Urol., 63: 1019, 1950. 6. Uhlenhuth, E.: Problems in the Anatomy of the Pelvis. Philadelphia: J.B. Lippincott, 1953. 7. Mitchell, J. P.: Injuries to the urethra. Brit. J. Urol., 40: 649, 1968.
Vol. 121, April
Copyright © 1979 by The Williams & Wilkins Co.
Printed in U.S.A.
UROLOGICAL INJURIES ASSOCIATED WITH PELVIC TRAUMA MILTON POKORNY, J. EDSON PONTES
AND
JAMES M. PIERCE, JR.
From the Department of Urology, Wayne State University School of Medicine and Detroit General Hospital Research Corporation, Detroit, Michigan
ABSTRACT
We reviewed 100 consecutive cases of pelvic fractures at our hospital to establish the relationship between bone injuries and urological lesions. There were 11 major urological injuries found: 6 patients had bladder laceration, 4 had rupture of the membranous urethra and 1 had a ureteral injury. Emphasis is placed on the physiopathology of the urological injuries. Frequently in the medical literature emphasis is placed on statistical reviews of certain subjects, such as numbers of 'urological injuries, while the pathologic mechanism of these entities is relegated to a secondary plan. This attitude leads to a poor understanding of the factors responsible for a certain pathology and a superficial view of the problems involved. Our study was done in an attempt to postulate the relationship between pelvic fractures and urological injuries. MATERIAL
A detailed review was made of 100 cases of major pelvic fractures seen at our hospital within the last 2112 years. The records of each patient were evaluated as to age, sex, cause of injury, type of fracture, and urological symptoms and signs. Urological diagnostic evaluation was done on every patient as described previously. 1 The radiographic records of each patient were evaluated to determine the type of injury and its possible relationship to the urinary tract involvement. RESULTS
Among the 100 patients there were 62 male and 38 female subjects, ranging in age from 13 to 80 years. Automobile accidents were responsible for 68 per cent of the injuries. Hematuria was present in 66 per cent of the patients and it was microscopic in 66 per cent of these. Two patients were seen for urinary retention after the fractures, 1 of whom underwent prostatectomy 6 months later. Further evaluation of the pelvic fractures revealed that 71 patients had fractures involving the pubic bone and 20 of these patients had both pubic bones fractured. Of particular interest are the unstable fractures of the pelvis caused by disruption of the anterior and posterior aspect of the pelvic ring, which are referred to as diametric2 or Malgaigne's fracture. This type of injury was seen in 14 patients and in 6 of these patients the displacement of the hemipelvis was owing to rupture of the sacroiliac joint and pubic symphysis without bone fracture (fig. 1). Diastasis of the pubic bones without any fracture was seen in 3 patients, none of whom had urological injuries. Associated injuries included fractures elsewhere in 42 patients, liver injuries in 2, rupture of the gallbladder in 1, laceration of mesenteric vessels in 1, head injuries in 7, rupture of the diaphragm in 1, rupture of the spleen in 2 and rupture of the right main bronchus in 1. Three patients died of the severity of the trauma before complete evaluation could be done. Among the 100 patients we found 11 major urological injuries in 10 patients. These included 6 ruptures of the bladder, 4 ruptures of the posterior urethra and 1 ureteral injury. One female subject had bladder and urethral lacerations owing to a comminuted pubic fracture. Accepted for publication July 28, 1978. 455
MECHANISM OF INJURY
Bladder injury. The probability of bladder injury is related to its distension. An empty bladder will be injured seldomly. Anatomically, bladder ruptures are either intraperitoneal or extraperitoneal. Of the 6 patients with rupture of the bladder 4 had intraperitoneal and 2 had extraperitoneal ruptures. The mechanism responsible for each type of injury is quite different. A full bladder frequently is involved in intraperitoneal ruptures. A sudden increase of pressure leads to rupture of the least supported surface of the bladder, the dome, with resulting intraperitoneal extravasation (fig. 2, A). Although this is the most common mechanism we postulate that a high fracture of the pelvic ring also could lead to a bladder rupture secondary to a bone fragment. The extent of pelvic fracture in intraperitoneal ruptures varied from a small fracture without displacement to a complex fracture. One patient had an intraperitoneal rupture associated with diastasis of the pubis and a fracture of the pubic rami. We believe that the common link among all of these patients was a full bladder. Extraperitoneal ruptures of the bladder in pelvic fractures commonly are associated with fracture of the pubis. Because of its close anatomical relationship a bony spicule often perforates the bladder. Another mechanism causing rupture is stress over the hypogastric wing and/or puboprostatic ligament and, finally, to the bladder wall. 3- 5 This occurs in diastasis of the pubis, associated or not with a diametric fracture. In 1 case the diastasis was accomplished by a comminuted fracture of the pubic rami with the possibility that a bony spicule was responsible for rupture at the bladder neck (fig. 2, B). Urethral injury. There are 4 mechanisms responsible for injury of the posterior urethra in pelvic trauma. The most common situation occurs in a diametric fracture when there is displacement of the hemipelvis upward, exerting traction on the hypogastric wing attached to the base of the bladder and prostate. 6 This upward displacement of the symphysis leads to the rupture of the puboprostatic ligament and stretching of the prostatomembranous urethra to the point of rupture. The bulbous urethra is not involved in the injury because it is fixed to the corpus spongiosum and central tendon. This type of fracture often is caused by a force acting over the ipsilateral femur. Of our patients 2 with rupture of the prostatomembranous urethra had this type offracture (fig. 3). Diametric fracture alone, without urological injury, was found in 10 additional patients, in some of whom stretching of the membranous urethra was noted without rupture. The second mechanism postulated occurs in bilateral fracture of the superior and inferior pubic rami. The fractured segment is displaced postero-inferiorly owing to a force acting over the pubis (fig. 4). We postulate that the sudden retrocession of the urogenital diaphragm against the membranous
Fm. 2 Origin of hypogastric artery
Fm. 3 456
UROLOGICAL INJURIES ASSOCIATED WITH PELVIC TRAUMA
457
G) Fm. 4
Fm. 5
urethra acts as a guillotine causing the urethral injury. One patient in this series had this type of injury (fig. 5). The third mechanism involves diastasis of the symphysis pubis with rupture of 1 puboprostatic ligament and tearing of the urogenital diaphragm from the contralateral bone. During the diastasis the membranous urethra will be pulled in 2 directions opposite to the point ofrupture. 7 The fourth mechanism proposed involves direct injury of the posterior urethra by a bony spicule during fractures of the pubis close to the midline. Ureteral injury. Rupture of the lower third of the ureter in blunt trauma is rare. A patient with multiple pelvic fractures and a partial laceration of the right ureter was encountered in this series. We postulate that the injury was caused most likely by a bony spicule after fracture of the right acetabulum. COMMENTS
Although the final picture seen on radiological examination does not reflect the dynamic forces at the time of injury we attempted to correlate the types of pelvic fractures most likely associated with urological injuries. Proper urological evaluation is necessary in order to decide the extent of injury and management. Although all of our 10 patients with major injury had gross hematuria we believe that all patients with hematuria, either gross or microscopic, need complete evaluation. Injuries of the bladder are often the result of forces acting upon a full bladder causing intraperitoneal rupture.
Extraperitoneal ruptures of the bladder are caused either by the direct impact of a bony spicule or by forces applied to anatomical ligaments of the bladder. Urethral injuries are the most serious complication of pelvic fractures. Mechanisms described to explain those ruptures include diametric fracture, bilateral fracture of the pubic rami with guillotine-like action at the membranous urethra, diastasis of the symphysis pubis with rupture of 1 puboprostatic ligament and direct injury owing to a bony spicule. REFERENCES
1. Pontes, J. E.: Urologic injuries. Surg. Clin. N. Amer., 57: 77,
1977. 2. Trunkey, D. D., Chapman, M. W., Lim, R. C., Jr. and Dunphy, J.E.: Management of pelvic fractures in blunt trauma injury. J. Trauma, 14: 912, 1974. 3. Monfort, J., Bainverl, J. V., Auvigne, J. and Buzelin, J.M.: Les complications urinaires immediates au cours des disjonctions de la symphyse pubienne. J. Urol. Nephrol., 79: 245, 1974. 4. Morehouse, D. D. and MacKinnon, K. J.: Urological injuries associated with pelvic fractures. J. Trauma, 9: 479, 1969. 5. Prather, G. C. and Kaiser, T. F.: The bladder in fracture of bony pelvis; the significance of a "tear drop bladder" as shown by cystogram. J. Urol., 63: 1019, 1950. 6. Uhlenhuth, E.: Problems in the Anatomy of the Pelvis. Philadelphia: J.B. Lippincott, 1953. 7. Mitchell, J. P.: Injuries to the urethra. Brit. J. Urol., 40: 649, 1968.
