The ureter is frequently injured during difficult abdominal or pelvic operations when the normal anatomy has been changed. It may also be injured when an ectopic kidney has altered the expected course of the ureter. Ureteral injury is a rare complication of operations on lumbar discs, and only a few cases of ureteral injury during lumbar laminectomy through a posterior approach have been described1.
In a search of the English-language literature, we found no case reports in which an injury of the ureter was associated with an anterior lumbosacral arthrodesis in a patient who had crossed renal ectopia with fusion and malrotation of the kidneys. We report the case of a patient who had such an injury in order to alert the reader to this rare cause of intraoperative injury of the ureter and to describe the successful treatment of this complication.
*No benefits in any form have been received or will be received from a commercial party related directly or indirectly to the subject of this article. No funds were received in support of this study.
†Markeweg 7, 9756 BZ, Glimmen, The Netherlands.
‡Departments of Urology (G. A. E. M. B. and A. F. G. V. M. Y.) and Orthopaedics (D. M. W.), St. Deventer Ziekenhuizen, Deventer, The Netherlands.
A forty-four-year-old woman who had had episodes of severe, chronic low-back pain for nineteen years was referred to one of us (D. M. W.), an orthopaedic surgeon, by her neurologist in 1988. She had had numerous evaluations and operations, including an appendectomy in 1953, an abdominal hysterectomy in 1982, and an excision of the most distal part of the os coecygis in 1984, without relief of the symptoms. In 1979, she had also reported dysuria, frequency of urination, nocturia, recurrent infection of the urinary tract, and constipation. In 1986, a urologist had had an intravenous urogram made during one of the evaluations. It showed crossed renal ectopia with fusion of the kidneys as well as malrotation of the left kidney, which was situated in the right part of the pelvis (Fig. 1).
When she was first seen by the orthopaedic surgeon (D. M. W.), the patient had a thorough orthopaedic and neurological evaluation, including a physical examination, computerized tomography, myelography, and discography. The presence of a herniated disc at any of the cephalad levels of the lumbar spine was excluded, and a diagnosis of severe disease of the disc between the fifth lumbar and first sacral vertebrae was made.
In May 1988, an anterior lumbosacral arthrodesis was performed with use of autogenous bone chips obtained from the region of the anterior superior iliac spine. Both the orthopaedic surgeon and the general surgeon reported that the procedure was completely uneventful in all respects.
Four weeks later, in June 1988, the patient began to have pain, abdominal distention, and a fever of more than 37.7 degrees Celsius that was associated with nausea and vomiting. Computerized tomography of the abdomen demonstrated a large mass (Fig. 2). An immediate exploration was performed by the same orthopaedic and general surgeons, and a urinoma was revealed. A urologist (G. A. E. M. B.) was consulted during the operation, and a ureteral catheter was inserted into the left ureter with use of a cystoscope. The catheter was easily identified in the center of the urinoma. After excision of all fibrous tissue, the defect in the left ureter was repaired with use of a tension-free but not watertight end-to-end anastomosis in combination with a double-J catheter.
The postoperative course was complicated by urosepsis, which caused a periodic elevation of temperature as well as an increased white blood-cell count and erythrocyte sedimentation rate. An intra-venous urogram demonstrated leakage of contrast medium at the site of the anastomosis. Operative exploration was performed in September 1988, nine weeks after the end-to-end uretero-ureterostomy, and the left ureter was found to be entrapped in edematous fibrotic tissue. The ureter was freed from the encasing tissue. The proximal portion of the left ureter was brought to the right ureter, which was situated nearby, and a transuretero-ureterostomy was performed without tension on the anastomosis and with sufficient ureteral blood supply (Fig. 3). The postoperative course was uneventful.
At a follow-up examination in July 1993, the findings of intravenous urography and ultrasonography were unremarkable. At the most recent follow-up examination, six years after the reconstructive procedure, the clinical condition of the patient was satisfactory.
An injury of an ectopic ureter associated with an anterior lumbosacral arthrodesis is an unusual but important finding. Our patient had a malrotated ectopic kidney in the right side of the pelvis that was fused with the upside-down, malrotated left kidney—crossed renal ectopia with fusion. Crossed renal ectopia is a condition in which renal tissue is drained by a ureter that crosses the midline before emptying distally3.
There are several types of fusion in crossed renal ectopia. Our patient had crossed renal ectopia with malrotation of the left kidney and fusion of the kidneys. To our knowledge, we are the first to describe this configuration. We suggest that this type of renal ectopia be termed malrotated, fused, and crossed renal ectopia.
The abnormal anatomical situation had not been identified by the surgeons during the first operation, and they were not aware of the urological findings. Therefore, an injury occurred easily. In addition, an injury of the ureter is asymptomatic. Symptoms do not occur until the urinoma, which is produced by a ureteral laceration, causes inflammation and infection, as occurred in our patient. Although computerized tomography revealed a urinoma in our patient, we believe that intravenous urography is a better imaging technique for patients who have a suspected ureteral injury. Intravenous urography has been reported to show abnormal findings, with extravasation of contrast medium at the site of injury, in 90 to 95 per cent of such patients4.
A wide variety of abnormal conditions, both congenital and acquired, can be associated with crossed renal ectopia or fusion anomalies. Serious non-urological disorders, such as orthopaedic (the most common), cardiovascular, gastrointestinal, respiratory, and other severe anomalies, can develop in as many as one in three affected individuals2,5. However, the unusual injury in our patient may have occurred because the surgeons were not familiar with the abnormal anatomical situation at the time of the anterior lumbosacral arthrodesis.
The reconstruction of the ureter at the second operation was not adequate. Although a double-J catheter was used, leakage of urine occurred at the site of the anastomosis. In general, a proper uretero-ureterostomy should consist of a watertight and tension-free anastomosis made of viable, non-dilated ureteral tissue that is provided with an adequate blood supply. The transuretero-ureterostomy that was performed nine weeks after the failed uretero-ureterostomy was successful. However, we were aware that, had it failed, a left nephrectomy might have been necessary.