Is It Possible to Draw a Risk Map for Obturator Nerve Injury During Pelvic Lymph Node Dissection? The Heilbronn Experience and a Review of the Literature.

Objective: Obturator nerve injury (ONI) is a rare complication during pelvic lymph node dissection (PLND), in extraperitoneal laparoscopic radical prostatectomy (e-LRP), and/or extraperitoneal robotic-assisted laparoscopic radical prostatectomy (e-RALP). It is important to recognize ONI during the initial operation, maximizing the feasibility of simultaneous repair. Here we report our experience with ONI during e-LRP/e-RALP procedures and draw an injury risk map.

Materials And Methods: Between December 1999 and November 2014, 2531 e-LRPs and 1027 e-RALPs were performed. Five patients (3 during e-LRP, 2 during e-RALP) experienced ONI in the proximal part of the nerve. Obturator nerves were clipped during the 3 e-LRP cases. Clips were immediately removed, and patients received physiotherapy with medical treatments in the postoperative period. During e-RALP, two obturator nerves were transected and subsequently repaired using the robotic Da Vinci(®) Surgical System (Intuitive Surgical, Inc., Sunnyvale, CA). ONI types were investigated in detail in these patients, and current published studies were analyzed in order to draw a risk map.

Results: Mean follow-up was 18.8 ± 2.7 months. In total, 3558 cases (2531 e-LRPs, 1027 e-RALPs) were performed. ONI occurred in 3 e-LRP (0.1%) and 2 e-RALP (0.1%) patients. Simultaneous repair was performed successfully in all cases, as clips were removed in e-LRP cases and obturator nerves were repaired using 6/0 polypropylene (Prolene(®); Ethicon, Somerville, NJ) suture in e-RALP cases. There was no complication associated with obturator nerve functions such as adductor function and/or neurologic deficiency during long-term follow-up. In view of published studies in the literature, the proximal part of the obturator nerve is at highest risk for injury during PLND, representing 77.8% of reported cases of ONI.

Conclusions: According to our ONI risk map, the proximal part of the obturator nerve is at higher risk for injury during PLND. Careful dissection and a good knowledge of pelvic anatomy are essential for preventing ONI. Successful ONI management can be performed simultaneously in experienced hands.