I read with great interest the article by Aasvang et al.  1on predictive risk factors for persistent postherniotomy pain. I congratulate the authors for their attention to a major problem associated with hernia repair. I would like to share some brief comments.

Herniotomy  means the separation, high ligation, and cutting of the hernial sac. It is a procedure done for infants and children as well as adults. In adults, and whenever suture is used to repair or strengthen the posterior inguinal canal wall, herniorrhaphy  is the more appropriate term. The Greek-based suffix “-rrhaphy” means “repair by suture.” Alternatively, mesh repair of inguinal hernia is a type of hernioplasty .

The authors detailed their methodology regarding measurements of sensory function before and after surgery, but they do not present adequate intraoperative data on Lichtenstein-sutured mesh repair. For example, was high ligation of the hernial sac done for all patients in this study group? The answer to this question may have had an impact on patient outcomes in that group.

In a randomized study of 477 patients undergoing herniorrhaphy, Delikoukos et al.  2found that pain levels were statistically significant in the study group that had high ligation of hernial sac compared with those in whom the sac as well as the herniated viscera was returned into the abdomen without opening the sac. Thus, high ligation and excision of the hernial sac may cause postherniorrhaphy pain, meaning that mesh is not the only causative factor in postherniorrhaphy pain.

In addition, many researchers have been unable to find statistically significant differences in postherniorrhaphy pain in relation to mesh use.3,4Many articles address the differences between heavy- and lightweight mesh with large pores in postoperative and long-term pain.5,6In the study by Aasvang et al. ,1two types of mesh were used, making a comparison of posthernioplasty pain levels difficult. Therefore, pain ratings in that study may have been the result of mesh type (lightweight in laparoscopy group, unknown in Lichtenstein group) in addition to operation type (laparoscopy vs.  Lichtenstein). In fact, mesh type may have had the major role.

In addition, Aasvang et al.  1present no data regarding postoperative complications observed. Postoperative complications may serve as an important intermediary variable. They were linked to increased risk for long-term pain in a study by Fränneby et al.  7Postoperative complications also increase the risk of recurrence, an independent risk factor for chronic postoperative pain after hernia surgery.8 

Finally, I believe the article would have benefited from the addition of information about the surgeons assigned to the Lichtenstein group. Specifically, how was nerve identification and preservation addressed by these surgeons? Caliskan et al.  9found that prophylactic ilioinguinal neurectomy decreases the incidence of physical activity–induced postoperative chronic pain without increasing the risk of sensory changes or postoperative complications. Others10claim that, when all three nerves are identified and preserved, no cases of chronic pain were identified at 6-month follow-up.

Although postherniorrhaphy pain decreases in frequency and intensity over time, researchers3,11,12have found that postintervention pain may persist for as long as 10 yr in postherniorrhaphy patients. In light of these data, I believe that the short, 6-month investigational course undertaken by Aasvang et al.  1does not fully address the aspect of persistence for postherniorrhaphy pain noted in the article's title.

Ayatollah Kashani Social Security Hospital, Tehran, Iran. bmh@irimc.org

Aasvang EK, Gmaehle E, Hansen JB, Gmaehle B, Forman JL, Schwarz J, Bittner R, Kehlet H: Predictive risk factors for persistent postherniotomy pain. Anesthesiology 2010; 112:957–69
Delikoukos S, Lavant L, Hlias G, Palogos K, Gikas D: The role of hernia sac ligation in postoperative pain in patients with elective tension-free indirect inguinal hernia repair: A prospective randomized study. Hernia 2007; 11:425–8
van Veen RN, Wijsmuller AR, Vrijland WW, Hop WC, Lange JF, Jeekel J: Randomized clinical trial of mesh versus  non-mesh primary inguinal hernia repair: Long-term chronic pain at 10 years. Surgery 2007; 142:695–8
Poobalan AS, Bruce J, Smith WC, King PM, Krukowski ZH, Chambers WA: A review of chronic pain after inguinal herniorrhaphy. Clin J Pain 2003; 19:48–54
O'Dwyer PJ, Alani A, McConnachie A: Groin hernia repair: Postherniorrhaphy pain. World J Surg 2005; 29:1062–5
Nienhuijs S, Staal E, Strobbe L, Rosman C, Groenewoud H, Bleichrodt R: Chronic pain after mesh repair of inguinal hernia: A systematic review. Am J Surg 2007; 194:394–400
Fränneby U, Sandblom G, Nordin P, Nyrén O, Gunnarsson U: Risk factors for long-term pain after hernia surgery. Ann Surg 2006; 244:212–9
Aasvang E, Kehlet H: Chronic postoperative pain: The case of inguinal herniorrhaphy. Br J Anaesth 2005; 95:69–76
Caliskan K, Nursal TZ, Caliskan E, Parlakgumus A, Yildirim S, Noyan T: A method for the reduction of chronic pain after tension-free repair of inguinal hernia: Iliohypogastric neurectomy and subcutaneous transposition of the spermatic cord. Hernia 2010; 14:51–5
Ferzli GS, Edwards E, Al-Khoury G, Hardin R: Postherniorrhaphy groin pain and how to avoid it. Surg Clin North Am 2008; 88:203–16
Bay-Nielsen M, Perkins FM, Kehlet H, Danish Hernia Database: Pain and functional impairment 1 year after inguinal herniorrhaphy: A nationwide questionnaire study. Ann Surg 2001; 233:1–7
Danish Hernia Database
Aasvang EK, Bay-Nielsen M, Kehlet H: Pain and functional impairment 6 years after inguinal herniorrhaphy. Hernia 2006; 10:316–21