Incisional Hernia After Midline Versus Transverse Specimen Extraction Incision

A Randomized Trial in Patients Undergoing Laparoscopic Colectomy

Lawrence Lee, MD, PhD; Juan Mata, MD; Raoul A. Droeser, MD; Pepa Kaneva, MSc; Sender Liberman, MD; Patrick Charlebois, MD; Barry Stein, MD; Gerald M. Fried, MD; Liane S. Feldman, MD


Annals of Surgery. 2018;268(1):41-47. 

In This Article

Abstract and Introduction


Objective: To compare the incidence of incisional hernia (IH) between midline and transverse specimen extraction site in patients undergoing laparoscopic colectomy.

Background: Midline specimen extraction incision is most commonly used in laparoscopic colectomy, but has high IH risk. IH may be lower for transverse incision.

Methods: A single-center superiority trial was conducted. Eligible patients undergoing laparoscopic colectomy were randomly assigned to midline or transverse specimen extraction. Primary outcome was IH incidence at 1 year. Power calculation required 76 patients per group to detect a reduction in IH from 20% to 5%. Secondary outcomes included perioperative outcomes, pain scores, health-related quality of life (SF-36), and cosmesis (Body Image Questionnaire).

Results: A total of 165 patients were randomly assigned to transverse (n = 79) or midline (n = 86) specimen extraction site, of which 141 completed 1-year follow-up (68 transverse, 73 midline). Patient, tumor, surgical data, and perioperative morbidity were similar. Pain scores were similar on each postoperative day. On intention-to-treat analysis, there was no difference in the incidence of IH at 1 year (transverse 2% vs midline 8%, P = 0.065) or after mean 30.3 month (standard deviation 9.4) follow-up (6% vs 14%, P = 0.121). On per-protocol analysis there were more IH after midline incision with longer follow-up (15% vs 2%, P = 0.013). On intention-to-treat analysis, SF-36 domains body pain and social functioning were improved after transverse incision. Cosmesis was higher after midline incision on per-protocol analysis, but without affecting body image.

Conclusions: Per-protocol analysis of this trial demonstrates that a transverse specimen extraction site has a lower incidence of IH compared to midline with longer follow-up but has worse cosmesis.


Minimally invasive approaches to colon resection have many advantages over open surgery, including less pain, shorter duration of ileus and improved quality of life.[1] A reduction in the rate of incisional hernia (IH) was a hoped for benefit of the smaller incisions enabled by laparoscopic surgery. However, long-term follow-up of laparoscopic versus open colectomy randomized trials have not demonstrated a difference in the incidence of IH.[2,3] A small midline laparotomy remains the most commonly used incision for specimen extraction in laparoscopic colorectal surgery,[4] but the rate of IH after midline laparotomy may be as high as 20%,[5] of which an important proportion are symptomatic.[6,7] There is some suggestion that IH may be reduced after transverse compared to midline laparotomy incision, which may offer an alternative specimen extraction incision for laparoscopic colectomy. Several prospective studies have reported a rate of IH after unilateral transverse laparotomy between 2% and 8%.[8–11] A Cochrane review of randomized trials comparing midline with transverse incisions concluded that transverse incisions were less painful, had less effect on pulmonary function, and were associated with decreased incidence of IH compared to midline incisions,[12] but these data involved open surgery only.[8–11]

Much of the data comparing the incidence of IH between different specimen extraction incisions in laparoscopic colorectal surgery report lower IH for off-midline incisions, although mostly consisting of heterogeneous observational studies.[13] To date, there exists a single randomized trial comparing midline and left lower quadrant transverse specimen extraction incisions for laparoscopic anterior resection. This trial did not report any difference in IH, but was limited by low numbers (20 per group) and short follow-up.[14] A reduction in IH would result in less long-term morbidity, reoperations, lower costs, and improved quality of life and functional outcomes.[15–18] Therefore, a randomized trial was undertaken to investigate the incidence of IH after midline versus transverse extraction incision for specimen extraction in patients undergoing laparoscopic colectomy.