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Inguinal hernia surgery

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Title: Inguinal hernia surgery  
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Subject: Digestive system surgery, Lower anterior resection, Hartmann's operation, Surgery, Hernia repair
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Inguinal hernia surgery

Surgical repair of a right inguinal hernia

Inguinal hernia surgery refers to a surgical operation for the correction of an inguinal hernia. Surgery is not advised in most cases, watchful waiting being the recommended option.[1][2] In particular, elective surgery is no longer recommended for the treatment of minimally symptomatic hernias due to the significant risk (>10%) of chronic pain (Post herniorraphy pain syndrome) and the low risk of incarceration (<0.2% per year).[3] As general advice in surgery, the choice of the surgeon and hospital are more important than the choice of a particular surgical technique or material.[4]


  • Mesh repairs 1
    • Open repair (Lichtenstein, Shouldice, Bassini) 1.1
    • Laparoscopic repair 1.2
    • Meshes 1.3
      • Permanent mesh 1.3.1
        • Commercial mesh
        • Mosquito-net mesh
        • Complications
      • Absorbable mesh 1.3.2
  • Suture repairs 2
    • Tension repairs 2.1
      • Bassini 2.1.1
      • McVay/Cooper's ligament 2.1.2
      • Shouldice 2.1.3
    • Tension-free repairs 2.2
      • Desarda 2.2.1
      • Guarnieri 2.2.2
  • References 3

Mesh repairs

Open repair (Lichtenstein, Shouldice, Bassini)

The most commonly performed inguinal hernia repair today is the Lichtenstein repair. A flat mesh is placed on top of the defect.[5]

It is a "tension-free" repair that does not put tension on muscles, contrary to Bassini and Shouldice suture repairs (but there are also tension-free suture repairs, like Desarda). It involves the placement of a mesh to strengthen the inguinal region. Patients typically go home within a few hours of surgery, often requiring no medication beyond paracetamol (Tylenol/acetaminophen). Patients are encouraged to walk as soon as possible postoperatively, and they can usually resume most normal activities within a week or two of the operation. Complications include chronic pain (varying from 10-50% depending on source), foreign-body sensation, stiffness, ischemic orchitis, testicular atrophy, dysejaculation, anejaculation or painful ejaculation in around 12%. They are often under-reported.[6][7][8][9] Recurrence rate is low, <2%.

Laparoscopic repair

Intraoperative view by TEP Operation. 1. Genital ramus of genitofemoral nerve. 2. Preperitoneal lipom and spermatic cord.

There are mainly two methods of laparoscopic repair: transabdominal preperitoneal (TAPP) and totally extra-peritoneal (TEP) repair. When performed by a surgeon experienced in hernia repair, lucrative and cause smaller incisions, resulting in less bleeding, less infection, faster recovery, reduced hospitalization, and reduced chronic pain.[10][11]

Laparoscopic mesh surgery, as compared to open mesh surgery
Advantages Disadvantages
  • Quicker recovery[11][12]
  • Less pain during first days[11]
  • Fewer postoperative complications[12]
such as infections, bleeding and seromas[11]
  • Less risk of chronic pain[11]
  • Needs surgeon highly experienced

(>200 operations/year) in inguinal hernia repairs

  • Longer operating time[12]
  • Increased recurrence of primary hernias if

surgeon not experienced enough[12]

There is no difference in cost between laparoscopic and open repair as the increased costs of operation are offset by the decreased recovery period. Recurrence rates are identical when laparoscopy is performed by an experienced surgeon.[11] When performed by a surgeon less experienced in inguinal hernia lap repair, recurrence is larger than after Lichtenstein.[13]


Permanent mesh

Commercial mesh
Polypropylene mesh used for inguinal hernia surgery

Commercial meshes are typically made of prolene (polypropylene) or polyester. Marlex, Gore-Tex or Teflon meshes are sold by some companies. Lightweight meshes seem to cause less discomfort than heavyweight meshes.[14] Some repair kits combine a plug and a patch. Some plug-and-patch kits combine an absorbable plug with a nonabsorbable patch, like Bio-A, manufactured by W. L. Gore.[15][16]

Mosquito-net mesh

Meshes made of mosquito net cloth, in copolymer of polyethylene and polypropylene have been used for low-income patients in rural India and Ghana.[17] Each piece costs $0.01, 3700 times cheaper than an equivalent commercial mesh.[18][19] They give results identical to commercial meshes in terms of infection and recurrence rate at 5 years.[18]

Therefore, it remains to be shown that despite their considerably higher cost, standard commercial meshes could offer any practical improvement over mosquito-net cloth in inguinal hernia surgery.[20]


Complications are frequent (>10%). They include, but are not limited to: foreign-body sensation,

  1. ^ Simons, M. P.; Aufenacker, T.; Bay-Nielsen, M.; Bouillot, J. L.; Campanelli, G.; Conze, J.; Lange, D.; Fortelny, R. et al. (2009). "European Hernia Society guidelines on the treatment of inguinal hernia in adult patients". Hernia 13 (4): 343–403.  
  2. ^ Rosenberg, J; Bisgaard, T; Kehlet, H; Wara, P; Asmussen, T; Juul, P; Strand, L; Andersen, FH et al. (2011). "Danish Hernia Database recommendations for the management of inguinal and femoral hernia in adults". Danish medical bulletin 58 (2): C4243.  
  3. ^ Fitzgibbons, R. J.; Giobbie-Hurder, Anita; Gibbs, James O.; Dunlop, Dorothy D.; Reda, Domenic J.; McCarthy, Martin; Neumayer, Leigh A.; Barkun, Jeffrey S. T.; Hoehn, James L.; Murphy, Joseph T.; Sarosi, George A.; Syme, William C.; Thompson, Jon S.; Wang, Jia; Jonasson, Olga (2006). "Watchful Waiting vs Repair of Inguinal Hernia in Minimally Symptomatic Men: A Randomized Clinical Trial". JAMA: the Journal of the American Medical Association 295 (3): 285–92.  
  4. ^ Flood, AB; Scott, WR; Ewy, W; Forrest Jr, WH (1982). "Effectiveness in professional organizations: The impact of surgeons and surgical staff organizations on the quality of care in hospitals". Health services research 17 (4): 341–66.  
  5. ^ Lichtenstein, IL; Shulman, AG (1986). "Ambulatory outpatient hernia surgery. Including a new concept, introducing tension-free repair". International surgery 71 (1): 1–4.  
  6. ^ Wantz, GE (1993). "Testicular atrophy and chronic residual neuralgia as risks of inguinal hernioplasty". The Surgical clinics of North America 73 (3): 571–81.  
  7. ^ Ridgway, P.F.; Shah, J.; Darzi, A.W. (2002). "Male genital tract injuries after contemporary inguinal hernia repair". BJU International 90 (3): 272–6.  
  8. ^
  9. ^ Aasvang, Eske Kvanner; Møhl, Bo; Bay-Nielsen, Morten; Kehlet, Henrik (2006). "Pain related sexual dysfunction after inguinal herniorrhaphy". Pain 122 (3): 258–63.  
  10. ^
  11. ^ a b c d e f "Hernia - laparoscopic surgery (review)". National Institute for Health and Clinical Excellence. 2004. Retrieved 2007-03-26. 
  12. ^ a b c d Trudie A Goers; Washington University School of Medicine Department of Surgery; Klingensmith, Mary E; Li Ern Chen; Sean C Glasgow (2008). The Washington manual of surgery. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins.  
  13. ^ Neumayer, Leigh; Giobbie-Hurder, Anita; Jonasson, Olga; Fitzgibbons, Robert; Dunlop, Dorothy; Gibbs, James; Reda, Domenic; Henderson, William; Veterans Affairs Cooperative Studies Program 456 Investigators (2004). "Open Mesh versus Laparoscopic Mesh Repair of Inguinal Hernia". New England Journal of Medicine 350 (18): 1819–27.  
  14. ^ Agarwal, Brij B.; Agarwal, Krishna A.; Sahu, Tapish; Mahajan, Krishan C. (2010). "Traditional polypropylene and lightweight meshes in totally extraperitoneal inguinal herniorrhaphy". International Journal of Surgery 8 (1): 44–7.  
  15. ^ Negro, P.; Gossetti, F.; Dassatti, M. R.; Andreuccetti, J.; d’Amore, L. (2011). "Bioabsorbable Gore BIO-A plug and patch hernia repair in young adults". Hernia 16 (1): 121–2.  
  16. ^ Instructions for Use - English - Gore Medical
  17. ^ Clarke, M. G.; Oppong, C.; Simmermacher, R.; Park, K.; Kurzer, M.; Vanotoo, L.; Kingsnorth, A. N. (2008). "The use of sterilised polyester mosquito net mesh for inguinal hernia repair in Ghana". Hernia 13 (2): 155–9.  
  18. ^ a b Tongaonkar, Ravindranath R.; Reddy, Brahma V.; Mehta, Virendra K.; Singh, Ningthoujam Somorjit; Shivade, Sanjay (2003). "Preliminary Multicentric Trial of Cheap Indigenous Mosquito-Net Cloth for Tension-free Hernia Repair". Indian Journal of Surgery 65 (1): 89–95. 
  19. ^ Wilhelm, T.J.; Freudenberg, S.; Jonas, E.; Grobholz, R.; Post, S.; Kyamanywa, P. (2007). "Sterilized Mosquito Net versus Commercial Mesh for Hernia Repair". European Surgical Research 39 (5): 312–7.  
  20. ^ Yang, J.; Papandria, D.; Rhee, D.; Perry, H.; Abdullah, F. (2011). "Low-cost mesh for inguinal hernia repair in resource-limited settings". Hernia 15 (5): 485–9.  
  21. ^ Amid, P. K. (2004). "Radiologic Images of Meshoma: A New Phenomenon Causing Chronic Pain After Prosthetic Repair of Abdominal Wall Hernias". Archives of Surgery 139 (12): 1297–8.  
  22. ^ Crespi, G; Giannetta, E; Mariani, F; Floris, F; Pretolesi, F; Marino, P (2004). "Imaging of early postoperative complications after polypropylene mesh repair of inguinal hernia". La Radiologia medica 108 (1–2): 107–15.  
  23. ^ Parra, J A; Revuelta, S; Gallego, T; Bueno, J; Berrio, JI; Fariñas, MC (2004). "Prosthetic mesh used for inguinal and ventral hernia repair: Normal appearance and complications in ultrasound and CT". British Journal of Radiology 77 (915): 261–5.  
  24. ^ Aguirre, D. A.; Santosa, A. C.; Casola, G.; Sirlin, C. B. (2005). "Abdominal Wall Hernias: Imaging Features, Complications, and Diagnostic Pitfalls at Multi-Detector Row CT". Radiographics 25 (6): 1501–20.  
  25. ^ a b Costello, C.R.; Bachman, S.L.; Grant, S.A.; Cleveland, D.S.; Loy, T.S.; Ramshaw, B.J. (2007). "Characterization of Heavyweight and Lightweight Polypropylene Prosthetic Mesh Explants from a Single Patient". Surgical Innovation 14 (3): 168–76.  
  26. ^ a b Ostergard, Donald R. (2011). "Degradation, infection and heat effects on polypropylene mesh for pelvic implantation: What was known and when it was known". International Urogynecology Journal 22 (7): 771–4.  
  27. ^ Klosterhalfen, B.; Klinge, U.; Hermanns, B.; Schumpelick, V. (2000). "Pathologie traditioneller chirurgischer Netze zur Hernienreparation nach Langzeitimplantation im Menschen" [Pathology of traditional surgical nets for hernia repair after long-term implantation in humans]. Der Chirurg (in German) 71 (1): 43–51.  
  28. ^ Shin, David; Lipshultz, Larry I.; Goldstein, Marc; Barm??, Gregory A.; Fuchs, Eugene F.; Nagler, Harris M.; McCallum, Stewart W.; Niederberger, Craig S. et al. (2005). "Herniorrhaphy with Polypropylene Mesh Causing Inguinal Vasal Obstruction". Annals of Surgery 241 (4): 553–8.  
  29. ^ Weyhe, Dirk; Belyaev, Orlin; Müller, Christophe; Meurer, Kirsten; Bauer, Karl-Heinz; Papapostolou, Georgios; Uhl, Waldemar (2006). "Improving Outcomes in Hernia Repair by the Use of Light Meshes—A Comparison of Different Implant Constructions Based on a Critical Appraisal of the Literature". World Journal of Surgery 31 (1): 234–44.  
  30. ^ Hallén, Magnus; Westerdahl, Johan; Nordin, Pär; Gunnarsson, Ulf; Sandblom, Gabriel (2012). "Mesh hernia repair and male infertility: A retrospective register study". Surgery 151 (1): 94–8.  
  31. ^ Fitzgibbons, Robert J. (2005). "Can We Be Sure Polypropylene Mesh Causes Infertility?". Annals of Surgery 241 (4): 559–61.  
  32. ^ Edelman, DS; Hodde, JP (2006). "Bioactive prosthetic material for treatment of hernias". Surgical technology international 15: 104–8.  
  33. ^ Ansaloni, Luca; Catena, Fausto; Coccolini, Federico; Gazzotti, Filippo; d'Alessandro, Luigi; Pinna, Antonio Daniele (2009). "Inguinal hernia repair with porcine small intestine submucosa: 3-year follow-up results of a randomized controlled trial of Lichtenstein's repair with polypropylene mesh versus Surgisis Inguinal Hernia Matrix". The American Journal of Surgery 198 (3): 303–12.  
  34. ^ Koopmann, M. C.; Yamane, B. H.; Starling, J. R. (2011). "Long-term Follow-up After Meshectomy with Acellular Human Dermis Repair for Postherniorrhaphy Inguinodynia". Archives of Surgery 146 (4): 427–31.  
  35. ^ Inguinal Hernia Repair with Biodesign® (Surgisis®) -- David Edelman, MD [1]
  36. ^
  37. ^ Hjort, H.; Mathisen, T.; Alves, A.; Clermont, G.; Boutrand, J. P. (2011). "Three-year results from a preclinical implantation study of a long-term resorbable surgical mesh with time-dependent mechanical characteristics". Hernia 16 (2): 191–7.  
  38. ^ Ansaloni, L.; Catena, F.; Coccolini, F.; Negro, P.; Campanelli, G.; Miserez, M. (2008). "New "biological" meshes: The need for a register. The EHS Registry for Biological Prostheses". Hernia 13 (1): 103–8.  
  39. ^ US Markets for Soft Tissue Repair Devices 2012,
  40. ^ doctor/3213 at Who Named It?
  41. ^ Bassini E, Nuovo metodo operativo per la cura dell'ernia inguinale. Padua, 1889.
  42. ^ Gordon, T. L. (1945). "Bassini's Operation for Inguinal Hernia". BMJ 2 (4414): 181–2.  
  43. ^ Arlt, G.; Schumpelick, V. (2002). "Die Leistenhernienoperation nach Shouldice – Aktuelle Technik und Ergebnisse" [The shouldice repair for inguinal hernia – Technique and results]. Zentralblatt für Chirurgie (in German) 127 (7): 565–9.  
  44. ^ Mittelstaedt, WE; Rodrigues Júnior, AJ; Duprat, J; Bevilaqua, RG; Birolini, D (1999). "Treatment of inguinal hernias. Is the Bassani's technique current yet? A prospective, randomized trial comparing three operative techniques: Bassini, Shouldice and McVay". Revista da Associacao Medica Brasileira 45 (2): 105–14.  
  45. ^ Mulholland MW and Doherty GM, ed. (2005). Complications in Surgery. Hagerstown, Maryland: Lippincott Williams & Wilkins. p. 533.  
  46. ^ Wennström, I; Berggren, P; Akerud, L; Järhult, J (2004). "Equal results with laparoscopic and Shouldice repairs of primary inguinal hernia in men. Report from a prospective randomized study". Scandinavian journal of surgery 93 (1): 34–6.  
  47. ^ a b Desarda, Mohanp (2008). "No-mesh inguinal hernia repair with continuous absorbable sutures: A dream or reality? (a study of 229 patients)". Saudi Journal of Gastroenterology 14 (3): 122–7.  
  48. ^ a b Desarda, M. P. (2005). "Physiological repair of inguinal hernia: A new technique (study of 860 patients)". Hernia 10 (2): 143–6.  
  49. ^ a b Manyilirah, W.; Kijjambu, S.; Upoki, A.; Kiryabwire, J. (2011). "Comparison of non-mesh (Desarda) and mesh (Lichtenstein) methods for inguinal hernia repair among black African patients: A short-term double-blind RCT". Hernia 16 (2): 133–44.  
  50. ^ Mitura, Kryspin; Romańczuk, Mikołaj (2008). "Porównanie dwóch metod operacyjnego leczenia przepuklin pachwinowych – sposobem Lichtensteina i Desarda" [Comparison between two methods of inguinal hernia surgery – Lichtenstein and Desarda]. Polski Merkuriusz Lekarski (in Polish) 24 (143): 392–5.  
  51. ^ Rodríguez, Pedro Rolando López; Herrera, Pablo Pol; Estrada, Jaime Strachan; Román, Jorge Caiñas; González, Olga León (2009). "Comparación entre la reparación abierta con malla y la técnica de Desarda en la hernia inguinal" [Comparison between open repair with mesh and the Desarda technique in inguinal hernia]. Revista Cubana de Cirugía (in Spanish) 48 (4). 
  52. ^ Desarda, Mohan P (2003). "Surgical physiology of inguinal hernia repair--a study of 200 cases". BMC Surgery 3: 2.  
  53. ^ Moneer, MM (1997). "A new preperitoneal repair for inguinal hernia using a transpositioned external oblique aponeurotic flap". Surgery today 27 (11): 1022–5.  
  54. ^ Lipton, S; Estrin, J (1991). "The aponeurotic repair of inguinal hernia". Today's OR nurse 13 (8): 26–32.  
  55. ^ Lipton, S; Estrin, J; Nathan, I (1994). "A biomechanical study of the aponeurotic inguinal hernia repair". Journal of the American College of Surgeons 178 (6): 595–9.  
  56. ^ Kuśnierczyk, R.; Piątkowski, W.; Wójcik, A. (2008). "Inguinal hernia repair with the peduncled fascial flap: A new surgical technique". Hernia 13 (2): 161–6.  
  57. ^ Guarnieri, A.; Guarnieri, F.; Moscatelli, F. (1997). "The functional repair of inguinal hernia". Hernia 1 (3): 117.  
  59. ^ Guarnieri, Antonio; Moscatelli, Franco; Guarnieri, Francesco; Ravo, Biagio (1992). "A new technique for indirect inguinal hernia repair". The American Journal of Surgery 164 (1): 70–3.  


Guarnieri technique appeared in 1988. It can be used with or without mesh.[57][58] Like Desarda technique, the Guarnieri method pays attention to the physiology, and it is also tension-free.[59]


The Desarda technique is an emerging suture-based technique.[48] It can be performed with absorbable sutures.[47] It is simpler and faster to perform than Shouldice and Lichtenstein.[49] It also gives similar results to Lichtenstein in terms of recurrence, with the significant benefit of not introducing permanent foreign-body material.[49][50][51] Moreover, this technique is tension-free,[52] mesh-free, and it pays attention to the physiology.[48] Other techniques using a flap from the external oblique aponeurosis were proposed independently by other surgeons.[53][54][55][56]


Tension-free repairs

Another advantage of suture-based repairs over permanent mesh repairs is that they do not introduce significant permanent foreign-body material, at worst, only polypropylene non-absorbable sutures. Permanent meshes can cause additional long-term complications due to this fact.

Moreover, if the surgeon is not experienced enough with the Shouldice technique, as is the case for most surgeons nowadays, mesh-based repair can be advised. For example, in developing countries, where commercial meshes are expensive, but where surgeons might also be less qualified, a mosquito-net mesh open repair can be better than Shouldice. Indeed, both have a similar cost (a mosquito-net mesh costs less than $0.01. Its sterilization costs less than $1), and mesh repair is easier to perform than Shouldice. Desarda repair is also another option, but it is less widely known.[47]

The main advantage of the Shouldice technique remains the relatively low report of chronic pain (10% incidence), as compared with mesh-based open repair (Lichtenstein) (20% incidence). However, the risk of chronic pain with this method is comparable to a laparoscopic repair performed by a surgeon experienced with inguinal hernia repair (i.e. >200 hernias/year) (8% incidence) (and not simply a surgeon experienced with laparoscopy. This difference is important).[46]

Shouldice repairs are less commonly used today than in previous years, especially in developed countries. This is mostly due to the fact that mesh-based Lichtenstein method is easier to perform. The Shouldice repair has a higher rate of hernia recurrence in the hands of surgeons inexperienced with them (<200 operations/year). Another drawback is the post-operative pain due to the tension on muscles, which generally lasts some weeks. However, this pain is well-managed with analgesics, and this short-term pain must be balanced with the much lower risk of long-term pain of the Shouldice technique, which is half Lichtenstein (but similar to laparoscopic). This is why few tension repairs are still in use today; these include the Shouldice and the Cooper's ligament/McVay repair.[44][45]

The Shouldice technique is the mainstream suture-based repair. It is a relatively difficult four layer reconstruction of fascia transversalis; however, it has relatively low reported recurrence rates in the hand of a surgeon experienced with this method.[43]


The floor of the canal is reinforced by approximating the transversus abdominal aponeurosis and transverse fascia to pectineal (Cooper's) ligament medially from the pubic tubercle to the femoral vein. Lateral to this the floor is restored by approximating the femoral sheath to the inguinal ligament. It is also used in femoral hernia repairs.

McVay/Cooper's ligament

The first efficient inguinal hernia repair was described by Edoardo Bassini in the 1880s.[40][41] The Bassini technique is a "tension" repair, in which the edges of the defect are sewn back together, without any mesh. In the Bassini technique, the conjoint tendon (formed by the distal ends of the transversus abdominis and internal oblique muscles) is approximated to the inguinal ligament and closed.[42] Today, Bassini's main interest is historical. It remains performed in some developing countries, if surgeons do not have knowledge of the mosquito-net alternative to commercial meshes in Lichtenstein repair, or if they ignore more efficient suture-based repairs.

Bassini technique, first suture. 1. Aponeurosis musculi obliq. ext.; 2. Musculus obliquus internus; 3. Musculus transversalis; 4. Fascia transversalis; 5. Peritoneum; 6. Ligamentum inguinale.


Tension repairs

Suture repairs

Though their benefit is not fully established yet,[38] the market of biological meshes is exploding, and if the current trend is confirmed, they may replace synthetic meshes in the US by 2016[39]

Biomeshes are increasingly popular since their first use in 1999[32] and their subsequent introduction on the market in 2003. Their use is an instance of regenerative medicine. Contrary to synthetic non-absorbable meshes, they are absorbable and they can be used for repair in infected environment, like for an incarcerated hernia. Moreover, they seem to improve comfort and presumably, they reduce the risk of inguinodynia.[33] They have been tested after mesh-related inguinodynia.[34] Some meshes have a comparable price to high end of synthetic meshes, the cheapest ($500) being Surgisis-Biodesign, manufactured by Cook Group, made from the extra cellular matrix of pig small intestinal submucosa.[35] Currently, there exist also one synthetic totally absorbable mesh, Tigr Matrix, manufactured by Novus Scientific, on the US market (510(k) Food and Drug Administration clearance)[36] since 2010 and on the EU market since 2011. It only has one 3-year pre-clinical evidence on sheep.[37]

Absorbable mesh

Cases of obstructive azoospermia have been related with the use of polypropylene mesh, due to the obstruction of the vas deferens as a result of the fibroblastic reaction to the mesh.[28][29] However, a recent study finds that this risk seems to be less than 1% [30] and therefore, it does not need to be notified in an informed consent.[31]

In the long term, polypropylene meshes face degradation,[25][26] due to heat effects. This increases the risk of stiffness and chronic pain.[25][26] Persistent inflammation and increased cell turnover at the mesh-tissue interface raised the possibility of cancer transformation.[27]

[24][23].bowel obstruction, or fistula, abscess Such complications usually become apparent weeks to years after the initial repair, presenting as [22]

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