V1-01: Radial Forearm Free Flap Substitution Urethroplasty for the Treatment of a Long Urethral Defect
We describe the surgical steps for performing a radial forearm free flap (RFFF) substitution urethroplasty in a patient with an obliterated urethral defect after failing an excision and primary anastomotic (EPA) urethroplasty for a pelvic fracture urethral injury (PFUI).
A 9-year old male involved in an all-terrain vehicle accident was initially treated at an outside hospital for non-operative pelvic fractures and a urethral disruption. He was managed with a suprapubic catheter. The patient was referred 5 months after the injury with a 3 cm obliterated bulbar urethral defect. We performed a posterior EPA urethroplasty with corporal splitting and partial inferior pubectomy. One month after surgery, an anastomotic leak was identified on retrograde urethrogram (RUG) imaging. The urethral catheter was removed and the patient was managed with a SPT. Two months after surgery, repeat imaging was performed and an obliterated urethral defect was identified. Due to the early failure of the repair, suggesting vascular compromise and/or technical failure, we proceeded with RFFF substitution urethroplasty.
The patient underwent RFFF urethroplasty under the coordinated care of the urology and microvascular plastic surgery team. Major steps included the following: 1) dissecting the urethra and measuring the length of the urethral defect, 2) harvesting the radial forearm free flap, 3) tubularizing the flap over a catheter, 4) preparing the recipient femoral vessels in the inguinal region, 5) performing the urethral-flap anastomoses, and 6) performing the microvascular anastomoses. Following excision of scar, the urethral defect measured 10 cm. The flap was harvested from the left forearm which was closed primarily. The operation was 8:45 with 180 cc of blood loss. During the microvascular anastomoses, an acoustic microvascular coupler was placed to audibly monitor the vascular flow of the flap during the post-operative period. The patient was kept on bed rest for 48 hours, and the patient was discharged home on post-operative day 4. After 3 weeks, the urethral catheter was removed and the SPT was kept to drainage since a small leak was visualized at the proximal anastomosis on RUG imaging. The SPT was removed 3 weeks later following no visual evidence of leak on imaging. The patient continues to void without obstructive symptoms 3 months after surgery.
Radial forearm free flap urethroplasty is a treatment option for long, obliterated urethral defects and should be performed in a multidisciplinary manner with the assistance of a microvascular plastic surgeon.