Internal trauma to the ureter is uncommon, but is more common than external trauma. Surgeons are the culprits! The ureters are most vulnerable to 'surgical' injury in the pelvis. Consider the anatomical relationships of the ureters. The left ureter is crossed by the left colic vessels and by those to the sigmoid colon at the pelvic brim. In the pelvis, the ureters pass anterior to the iliac vessels, and then they turn medially at the level of the ischial spines to approach the bladder. In females, the ureter lies at the base of the broad ligament and is crossed anteriorly by the uterine artery just before entering the bladder. Not surprisingly, therefore, the ureters are vulnerable to injury during hysterectomy, oophorectomy, and sigmoid colectomy. The other obvious source of surgical injury, (probably the commonest cause) is ureteroscopy. Less commonly, the ureter may be damaged during caesarean section, aortoiliac vacular graft placement, laparo-scopic procedures, and orthopaedic operations including spinal surgery and total hip replacement (Fig. 5.5). The ureter may be cut in one place, a segment may be excised along with the organ being removed, it may be ligated or angulated by a suture, or it may sustain a diathermy injury or undergo ischaemic necrosis if the blood supply to one segment is damaged.
Making the Diagnosis
This requires a high index of suspicion, particularly in cases of external trauma where the focus of attention may be on other, obvious injuries. In the case of hysterectomy or colectomy, injury to the ureter is usually, but not always, apparent at the time of surgery. The cut ureter has a characteristic appearance—familiar to those who have inadvertently divided it! It looks like no
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FIGURE 5.5. Extruded cement from a total hip replacement with a JJ stent in the ureter. There was no ureteric injury in this case, but it demonstrates that the anatomical path of the ureter may be distorted, and therefore the ureter potentially injured, during total hip replacement.