The use of a mesh in diastasis recti surgeryin order to provide support for the abdominal wall and reduce the incidence of recurrenceshas in recent years become one of the cornerstones of the surgical treatment of diastasis.
This, however, has given rise to a debate that is now more heated than ever, topical and of primary importance for patients: where should be placed the mesh?
In fact, there are numerous sites for placing a mesh in the abdominal wall, as can be seen in the figure below. What is the right place for the mesh in diastasis surgery?
In many respects, it is easier to say where one should never put it.
One of the principles of good practice that has been gaining ground in recent years is that of minimise and, if possible, proscribe the use of intra-abdominal meshes.
This is because no type of material is currently available that is completely non-stick, and nets implanted in an intraperitoneal situation tend to induce adhesions between the prosthetic material and the peritoneum of the viscera. There is an increasing amount of reporting in the literature about this topic, often in journals with a high Impact Factor.
This is also one of the 'hot' topics in the Abdominal Wall Surgery Congresses: the placement of an intraperitoneal mesh (we could also say a 'intraperitoneal foreign body') has long been the basic technical prerequisite for laparoscopic repair of abdominal wall defects: the first laparoscopic technique proposed for wall defect surgery was the IPOM (Intra Peritoneal Onlay Mesh), in which the mesh is placed as a 'bridge' over the wall defect, as seen in the image below.
Over time, it became apparent that bridge' repair is inefficient: in fact, a dead space is left between the mesh and the abdominal wall in which seromas form with a certain frequency; bulging of the mesh through the herniary defect can occur, which tends to form pseudo-hernias; shrinking (i.e. the retraction of the mesh, which occurs with all prosthetic materials) can lead to the formation of recurrences.
For this reason, in 2014 Jan Kukleta, one of the 'holy monsters' of European wall surgery, proposed the 'IPOM plus' (Surg Endosc. 2014;28:2-29), technique in which the defect, before being 'covered' with intraperitoneal mesh, is sutured. With the IPOM plus technique, dead spaces between the mesh and the abdominal wall are eliminated, thus reducing the incidence of seromas. The incidence of recurrences due to shrinkage of the prosthesis is also reduced, provided that the suture of the herniated defect is tension-free. IPOM plus does not, however, solve the main problem intrinsic to the technique itself: the presence of a mesh in contact with the peritoneal viscera.
I would like to introduce at this point a text that I will refer to constantly from now on. It is the beautiful volume "The Art of Hernia Surgery. A Step-by-Step Guide" published by Springer in 2018, whose Editor, Prof. Giampiero Campanelli of the University of Insubria, is not to be missed by anyone involved in abdominal wall surgery, as he has been one of the undisputed European leaders in this discipline for decades, and has held central roles including President of the European Hernia Society (EHS, the most important abdominal wall surgery society on our continent) and Editor-in-chief of Hernia, the leading abdominal wall surgery journal published today.
The chapter on IPOM and IPOM plus techniques in this book (ch. 58, pp. 572-581) was written by Jan Kukleta himself; the two pictures above are taken from that very chapter. In the conclusion, Kukleta writes: "Both IPOM classic and IPOM Plus have a common weak point: the intraperitoneal mesh and its fixation"Kukleta himself, the official 'creator' of IPOM Plus, acknowledges that the intraperitoneal mesh is a limitation. Kukleta ends his chapter by writing: "There are several techniques how to use augmenting mesh in extraperitoneal position using minimally invasive approach. Until we'll learn to differentiate their potential and to find out which one fits best to which condition, I would propose to name this new group-'Minimally Invasive Non-Intraperitoneal Mesh Repair' -MINIM Repair".
This, then, is the marked path: placing the mesh outside the peritoneum.
I could at this point cite quite a bit of literature on the risks and complications of intraperitoneal mesh placement in wall repairs: I will just take a 'bird's eye view' of a few important articles, and then turn to another chapter in Campanelli's book.
- Gray SH, Vick CC, Graham LA, Finan KR, Neumayer LA, Hawn MT. Risk of complications from enterotomy or unplanned bowel resection during elective hernia repair. Arch Surg. 2008;143(6):582-6. Archives of Surgery is the former name of the current JAMA Surgeryimpact factor 14.8, 'the highest ranking surgery journal in the world' as stated on the journal's own website. The cited article reviews 1124 elective incisional hernia repair surgeries realized between 1998 and 2002. In 13.3% of the cases, these were patients with recurrence of prosthetic wall defect plastics. In these patients, the risk of intestinal injury due to mesh-induced lysis of adhesions was 20.3% versus 5.3% in patients who had undergone first laparocele plastic surgery and 5.7% in patients who had undergone recurrence plastic surgery but in whom a mesh had not been placed in the first operation.
- Kokotovic D, Bisgaard T, Helgstrand F. Long-term Recurrence and Complications Associated With Elective Incisional Hernia Repair. JAMA. 2016;316(15):1575-1582. Still from JAMA. Analysis of 3242 patients who underwent hernia repair surgery (open without prosthesis, open with prosthesis, laparoscopic with prosthesis) between 2007 and 2010 and followed up until 2014. I report the conclusions verbatim: "For the entirety of the follow-up duration, there was a progressively increasing number of mesh-related complications for both open and laparoscopic procedures. At 5 years of follow-up, the cumulative incidence of mesh-related complications was 5.6%(95%CI, 4.2%-6.9%) for patients who underwent open mesh hernia repair and 3.7%(95%CI, 2.8%-4.6%) for patients who underwent laparoscopic mesh repair. The long-term repair-related complication rate for patients with an initial nonmesh repair was 0.8%". That is, throughout the follow-up, there was a progressively increasing number of mesh-related complications for both open and laparoscopic procedures. At 5-year follow-up, the cumulative incidence of mesh-related complications was 5.6% (CI 95%, 4.2%-6.9%) for patients undergoing open hernia repair and 3.7% (CI 95%, 2.8%-4.6 %) for patients undergoing laparoscopic repair. The long-term repair-related complication rate for patients undergoing initial repair without mesh was 0.8%.
- Muysoms FE, Bontinck J, Pletinckx P. Complications of mesh devices for intraperitoneal umbilical hernia repair: a word of caution. Hernia. 2011;15(4):463-8. As already mentioned, Hernia is the most important journal exclusively dedicated to abdominal wall surgery published today. Its latest Impat factor, for 2020. is 4.739. The editor-in-chief is Prof. Giampiero Campanelli. In this article, the authors present a personal case history of complications (intestinal perforation, herniated recurrence) that occurred to them following the use of intraperitoneally placed dualmesh nets. In one case the mesh had migrated into the intestine. This is the image published by the authors. Among the authors' conclusions, one is central and hugely significant: "There is a complete lack of convincing data on these mesh devices in the medical literature. No long-term data have been published and, for three of the four mesh devices available, no publications on their use in humans were found.. That is the point: there is no independent, peer reviewed information on these meshes: we only know what we are told about them by the companies that produce them. On the other hand, reports on the complications caused by them are increasingly important and authoritative.
The problem of mesh migration within the intestine is well present in literature. Here are some bibliographical references:
Nelson EC, Vidovszky TJ. Composite mesh migration into the sigmoid colon following ventral hernia repair. Hernia. 2011;15(1):101-3
Horzic M, Vergles D, Cupurdija K, Kopljar M, Zidak M, Lackovic Z. Spontaneous mesh evacuation per rectum after incisional ventral hernia repair. Hernia. 2011;15(3):351-2.
Carpelan-Holmström M, Kruuna O, Salo J, Kylänpää L, Scheinin T. Late mesh migration through the stomach wall after laparoscopic refundoplication using a dual-sided PTFE/ePTFE mesh. Hernia. 2011;15(2):217-20
Rodrigues-Pinto E, Costa-Moreira P, Santos AL, Dias E, Macedo G. Endoscopic removal of migrated Nissen fundoplication mesh. VideoGIE. 2020;5(6):238-240
Li J, Cheng T. Mesh erosion after hiatal hernia repair: the tip of the iceberg? Hernia. 2019;23(6):1243-1252
Cunningham HB, Weis JJ, Taveras LR, Huerta S. Mesh migration following abdominal hernia repair: a comprehensive review. Hernia. 2019;23(2):235-243
The list is necessarily incomplete, but I would like to draw attention to the title of Li and Cheng's work: "The tip of the iceberg?"One of the cruxes of the matter is exactly this: the follow-up of patients undergoing abdominal wall surgery is usually short, often very short, and therefore insufficient to determine exactly what and how many long-term complications intraperitoneal mesh may cause. An adverse event may be reported when a patient who has already undergone this particular type of repair is re-operated (for example, as in the reported cases, for intestinal occlusion or perforation), but how many patients with adherence syndrome, subocclusive crises, chronic abdominal pain, etc. are lost along the way? The reports in the literature are chilling, but in all likelihood they are really only the tip of the iceberg.
I would now like to turn to another chapter of Prof. Campanelli's book; namely chapter 57 (pages 563-569) written by Prof. Francesco Corcione. Prof. Corcione, a world-renowned surgeon and former president of SIC (Italian Society of Surgery), needs no introduction. The chapter is entitled "Laparoscopic Ventral Hernia Repair: Where Is the Border?".
I will quote some excerpts, to summarise would be a shame.
"If we affirm that the safety of the intraperitoneal meshes is supported by the results of more than 20 years of laparoscopic surgery in abdominal wall surgery, it is difficult to understand why the companies has developed always new meshes, even replacing the previous ones, saying that the new one is the best one; and some meshes have been recalled from the market by the companies themselves!" it is difficult to understand why companies have developed new networks all the time, even replacing the previous ones, saying that the new one is the bestand some networks have been withdrawn from the market by the companies themselves!"
" The adhesions are practically always present after any kind of mesh implant, regardless of the type of material used, and we can be sure that a real anti-adherent mesh still doesn't exist." - "Adhesions are practically always present after any type of mesh implant, regardless of the type of material usedand we can be sure that a true non-stick net does not yet exist."
"The introduction of the Goretex mesh started a new era for the surgeons, although the mesh being very expensive. As a matter of fact, it has to be said that the Rives technique was difficult to be perceived by surgeons, who probably thought it was more logical, quick, and equally safe placing a mesh in the abdomen that was described as anti-adherent. But only a few surgeons systematically used this prosthesis, which soon revealed to be "adherent," causing a large number of obstructive complications and cases of migration into the jejunum, bladder, colon, etc." probably considered it more logical, quicker and equally safe to place a defined non-stick mesh in the abdomen. But only a few surgeons systematically used this prosthesis, which soon turned out to be 'adherent', causing a large number of obstructive complications and cases of migration into the small intestine, bladder, colon, etc..".
"I have personally experienced intra-abdominal mesh-related complications at a distance of 1-15 years from their implantation. I saw the formation of a parietal abscess 7 years after laparoscopic ventral hernia repair, sustained by a very late infection of the mesh. I have seen recurrences appeared 1 month (probably technical error) and 20 years after the surgery. I have treated many intra-abdominal prostheses migrations. I also saw migration of a mesh into the oesophagus after hiatal hernia repair that required an oesophagectomy." formation of a parietal abscess 7 years after laparoscopic repair of a ventral hernia, sustained by a very late net infection. I saw recurrences 1 month (probably a technical error) and 20 years after surgery. I have treated many migration of intra-abdominal prostheses. I also saw the migration of a network into the oesophagus after repair of a hiatal herniawhich required a oesophagectomy“.
"For decades a lot of patients (particularly complex cases and complications very difficult to deal with) referred to our hospital. As can be seen from the table, we have treated 37 patients with complex and risky interventions, with long postoperative stay. In the table the complications due to the previous mesh are described. - "For decades, many patients (particularly complex cases and very difficult to treat complications) have turned to our hospital. As can be seen from the table, we have treated 37 patients with complex and risky operations and long postoperative stays. Complications due to the network are described in the table'.
The network in rectus diastasis surgery: conclusions.
"Laparoscopic surgery, which in our experience is largely adopted for the treatment of most major abdominal diseases, has now strict and limited indications for the treatment of ventral hernia." – 'Laparoscopic surgery, which in our experience is widely adopted for the treatment of major abdominal pathologies, now has strict and limited indications for the treatment of ventral hernia'.
Prof. Corcione's words are lapidary and leave little room for appeal. It should be noted, however, that he means the adjective 'laparoscopic' in the literal sense of the term, i.e. as intra-abdominal surgical field. Today, several advanced techniques, more accurately defined as 'endoscopic', are available and allow the principles of minimally invasive surgery to be applied to abdominal hernias as well, positioning the mesh well away from the peritoneum.
REPA is the main one among these techniques: with a mesh placed on the external surface of the abdominal wall, well away from the pritoneal viscera, the unfavourable events we have mentioned so far are 0. This is one of the reasons why REPA today, even in some guidelines (such as that of the Sociedad Hispanoamericana de Hernia), is beginning to be considered the gold standard for minimally invasive rectus diastasis surgery.