Anterior lumbar interbody fusion in the setting of ectopic pelvic kidney

Abstract

Objective

We present the case of a 69-year-old female with an ectopic pelvic kidney (EPK) who was indicated for an anterior lumbar interbody fusion (ALIF). We describe the use of a trans-abdominal transperitoneal approach with medial visceral rotation and the details of this patient’s unique renal anatomy.

Summary of background data

ALIF has been associated with decreased pain, enhanced recovery, and increased fusion rates compared with other lumbar fusion techniques. This approach involves dissection through the lower abdomen to the spine, requiring a thorough understanding of relevant anatomy and anatomic variations.

Methods

A 69-year-old female with an EPK presented with left lower extremity radicular pain. She had failed conservative management and an ALIF was recommended. Preoperative MRI and CT imaging delineated the unique location of the kidney and numerous renal vascular anatomic variations. However, other anomalous vascular and ureterovesical structures could not be excluded. For this reason, the authors opted to use a transabdominal transperitoneal approach.

Results

Our approach consisted of a midline-transabdominal-transperitoneal incision to include the skin, subcutaneous tissue, and linea alba. Once the peritoneum was entered, the omentum was packed cephalad, and the small bowel was wrapped and mobilized to the right. The EPK was rotated cephalo-medially and its three renal arteries were located, dissected, and carefully protected. After adequate exposure of the L4-L5 interbody space, a discectomy was performed, followed by implantation of a lumbar interbody fusion cage filled with allograft bone. The patient proceeded to have an uneventful recovery, with a mild increase in creatinine on postoperative day one, which normalized by her discharge on postoperative day four.

Conclusion

EPK is a congenital anomaly that can present with complex and variable anatomy. When planning to perform an ALIF in the setting of EPK, complex and anomalous vascular anatomy should be expected. Therefore, strong consideration may be given to imaging, though underlying vascular structure cannot be ruled out. We describe a trans-abdominal transperitoneal approach with medial visceral rotation, as this approach may provide the highest flexibility to avoid inadvertent complications during ALIF in patients with EPK.

Level of evidence

Level IV.