1. Background {#sec1}
=============

Since laparoscopic surgery was introduced in 1987 by Mouret and more frequently employed, it has rapidly evolved as a major innovation in the history of surgery \[[@B1]\], offering an important contribution to the reduction of all the typical complications related to open surgery. On the other hand, laparoscopic surgery can be associated with a specific type of incisional hernia through the trocar site causing complications such as small bowel obstruction. Trocar site hernia (TSH) is defined as an incisional hernia which occurs after minimally invasive surgery on the trocar incision site \[[@B2]\]; some authors also define this condition as a port site hernia.

In 2004 Tonouchi classified trocar site hernias into 3 types \[[@B3]\] as follows.

\(i\) Early onset typeDehiscence of anterior and posterior fascial plane and peritoneum characterized by early onset after surgery. It usually occurs as a small bowel obstruction. An example of this type is the so-called Richter\'s hernia.

\(ii\) Late onset typeDehiscence of anterior and posterior fascial plane. Peritoneum constitutes the hernia sac. Hernias usually develop several months after surgery and they are not associated with small bowel obstruction. They appear as an asymptomatic swelling by the wound site.

\(iii\) Special typeDehiscence of the whole abdominal wall. Intestine and/or omentum protrusion. There is no sac, being not a typical herniation. Its onset is very early, immediately after surgery.

2. Case Report {#sec2}
==============

We report the case of a 76-year-old woman who underwent a laparoscopic left hemicolectomy for a sigmoid tumour. The patient was discharged in good general conditions and with open alvus on the 7th postoperative day.

Three days after discharge, the patient was affected by colicky abdominal pain mostly localized in the left upper quadrant, vomiting, and constipation which required a rehospitalization. On the clinical examination the abdomen was distended and tender particularly in the left upper quadrant; an oval mass (5 cm) was detected in the same abdominal quadrant near the 12 mm trocar site. The ultrasound scan showed a swelling constituted by entrapped intestinal loops, and the abdominal X-ray revealed multiple small bowel gas-fluid levels. Because of the clinical, US and radiological signs of obstruction, the patient underwent an emergency explorative laparotomy which showed a small bowel herniation through the trocar incision site in the left upper quadrant ([Figure 1](#fig1){ref-type="fig"}); the intestinal loop appeared necrotic and had to be resected, and the hernia orifice was repaired. The patient was discharged on the 8th postoperative day.

3. Discussion {#sec3}
=============

Trocar site hernia is a complication that is likely to be minimized \[[@B4]\].

The clinical onset of a trocar site hernia is usually early as it often occurs within the 30th postoperative day, and it is due to the omentum or small bowel entrapment into the trocar wound. The intestinal occlusion clinical presentation is often insidious, with progression to an acute abdomen, and an early and emergency surgical approach is often required \[[@B3]--[@B5]\].

The first trocar site hernia case was described by Fear in 1968 \[[@B6]\]. In this report, herniation of a small bowel loop was noticed in the immediate postoperative time. This was also the first case of the "special type hernia" described by Tonouchi. So this first report tended to express a protrusion of the bowel and/or omentum as a "hernia,\" although in the described type no hernia sac was detected \[[@B1]--[@B3]\].

In 1974 Schiff and Naftolin reported two cases of small bowel herniation occurred between the 14th and 21st postoperative days that required laparotomy with small bowel resection \[[@B7]\].

One of the first multicentric reports of operative laparoscopy revealed six incisional hernias out of 3560 cases (0.17%). These included four small bowel herniations and two omental herniations. Five of the six herniations were detected through a 12 mm port site, showing that the risk of herniation through a 12 mm trocar site was approximately 3-fold greater than that of a 10 mm trocar site. All the herniations were extraumbilical, and in three of the four cases of small bowel herniation, the fascia had been sutured. In this report Kadar et al. described cases of extraumbilical port site hernia, and for the first time two of the patients were treated laparoscopically \[[@B8]\].

In 1994 an amount of 933 hernias was reported from a 4,385,000 estimated laparoscopic procedures (0,02%) by the American Association of Gynecologic Laparoscopists. 167 (17.9%) were reported to have occurred despite fascial closure. 665 patients (71.3%) required a following surgical repair. 725 (86.3%) of the 840 hernias in which the size of the original fascial defect was noted occurred in sites where 10 mm or larger diameter trocars had been placed. Only 10.9% (92/840) were related to the use of 8--10 mm trocars and only 2.7% (23/840) to minor diameter trocars. The hernias occurrence in this report is a function of the number of the performed laparoscopic procedures (*P* \< .0001), and it is not related to the surgeon\'s experience (*P* = .41) \[[@B9]\].

These data are shared by the study reported by Tonouchi; indeed, according to his work, 78.3% of hernias occurred on the 10--12 mm trocar site, while 21.7% occurred on the site of a trocar whose diameter was ≤5 mm \[[@B3]\].

In 1995, Boike et al. described 19 cases with 21 bowel herniation from 11 participating institutions. Two patients showed incisional herniation simultaneously on two port sites. Of the 21 herniations, 12 (57%) occurred on 12 mm port sites, 8 (38%) on 10 mm port sites, and one on 11 mm port site. Fascial screws were used to anchor ports in 11 (57%) patients with herniations. An attempt to close the fascia was performed in 9 patients (43%) during primary surgery. 16 herniations (76%) occurred on extraumbilical sites and 5 (23%) on the umbilical port site. The hernia contained small bowel in 18 cases (21%), cecum in 2 cases (0.9%), and ascending colon in 1 case (0.4%). The average interval to second operation was 8.5 days (range 2 to 42 days). In 3 patients (14%) the bowel herniation was repaired laparoscopically, while two patients (0,9%) required small bowel resection \[[@B4]\].

From 1995 till 1996, on a total of 32,205 gynaecological laparoscopies, 130 major complications were registered by the National Patient Insurance Association and 8 incisional hernias were reported (0.025%). The complications following operative laparoscopies included 48% urethral injuries, 19% bladder injuries, 13% intestinal injuries, 7% incisional hernias, 2% large-vessel injuries, and 11% different injuries. Incisional hernias were diagnosed between the 2nd and 14th postoperative days. The size of the trocars ranged from 5 to 12 mm; small bowel resection was needed in three patients (38%) \[[@B10]\].

Boughey et al. in 2003 described four cases of Richter\'s hernia after laparoscopy, two of which were repaired by open procedure and two by laparoscopy. The authors concluded that a laparoscopic hernia repair is an acceptable treatment at the time of diagnosis, especially in obese patients, as long as the incarcerated bowel is not severely compromised or ischemic \[[@B11]\].

In 2006, Immè and Cardi. studied 600 patients undergoing laparoscopic surgery. The incidence of incisional hernia was estimated around 2%, exclusively in the periumbilical area. No incisional hernia in extra-umbilical areas was registered, despite the authors did not use to perform fascial suture on extraumbilical sites. This study underlined the fact that particular attention needs to be paid to periumbilical gap suture which is exposed to the trauma of trocar fixing, especially in obese and diabetic patients. In selected cases the other gaps should be sutured, including the 5 mm ones \[[@B12]\].

Trocar site hernia is also one of the major complications after laparoscopic ventral hernia repair (LVHR). Its incidence was reported around 22% in a recent study published by Boldò et al. in 2007. This report showed a higher incidence in the TSH group of female gender, patients treated with large meshes, and patients affected by diabetes; but the use of meshes larger than 10 × 15 cm for LVHR was the only TSH risk factor to reach statistical significance. The cause for this finding is probably due to the dilatation of the trocar orifice during the introduction of the mesh and also to a postoperative mesh retraction \[[@B13]\].

Although trocar site hernias are well-known postoperative complications after laparoscopic surgery in adult patients, they have also been reported in preschool children. In 2008 Paya et al. conducted a retrospective reviewed of 293 laparoscopic procedures performed at a pediatric surgical tertiary care unit during a period of 4 years. 8 severe postoperative complications (2.7%) were described, and three of those were trocar site hernias (1.0%). All of them were omental hernias, and in all cases they were treated between the 3rd and 4th postoperative day. In all the patients, sharp-edged or pointedly round tips 2 to 5 mm sized trocars were used. Trocar site closure was performed using double-layer sutures for the first trocar, while the other trocar sites closure was performed carrying out one single suture including all layers \[[@B14]\].

Before this work there was only one published series, for children and adolescents up to 19 years of age, reporting an incidence of trocar site hernia of 0.3% (2 out of 574 patients) \[[@B15]\].

Although TSH in adult patients is mostly limited to ≥10 mm trocars, in 1999 Eltabbakh. reported the case of a 54-year-old woman who presented small bowel obstruction and herniation through a 5-mm trocar site 1 week after a laparoscopically assisted vaginal hysterectomy and bilateral salpingo-oophorectomy \[[@B16]\].

Since 1999 the purpose of several reports has been to focus on trocar-related problems with special respect to the tip design, concluding that port sites created by nonbladed trocars could not require fascial closure. Indeed, Kolata demonstrated that the wounds made by nonbladed trocars were narrower than those created by cutting tip trocars in a pig experimental model \[[@B17]\].

Leibl et al. compared two groups of patients treated in a nonrandomized design with either sharp cutting single-use trocars or cone-shaped noncutting reusable trocars. This trial showed an incisional hernia in 1.83% of patients treated with a sharp trocar tip, a complication which could be significantly lowered down to 0.17%, by using a conic tip design. So they demonstrated a reasonable benefit for a conic tip design, which enables an atraumatic insertion through the abdominal wall \[[@B18]\].

In 2000 Liu and McFadden reported 180 laparoscopic port sites performed with nonbladed trocars without fascial closure. Upon removal of large laparoscopic ports, the fascial defect was less than 6 to 8 mm, and the muscles of the abdominal wall covered the port site defect. The anterior fascial defect did not line up with the posterior fascial defect after removal of CO2 insufflation. No patient developed ventral incisional hernias in the postoperative period. The conclusion of the study was that the use of nonbladed laparoscopic trocars appears to be a safe technique, allowing to visualize dissection through the abdominal wall layers and to create the smallest port dissection without cutting muscle fibers and with no bleeding risk. The possibility to disrupt the abdominal wall musculature allows the surgeon to avoid the closure of the small fascial defect \[[@B19]\].

Johnson et al. performed a retrospective review of 747 operative procedures using VersaStep trocar system, one of nonbladed laparoscopic trocars, in patients undergoing Roux-en-Y gastric bypass surgery. There were no hernias detected at any of the 1494 12-mm or 2241 5-mm VersaStep trocar sites, despite lack of suture closure. At the Hasson port site, there was a hernia incidence of 1.20% \[[@B20]\].

In 2007 Shaher reviewed different wound closure techniques by a literature search \[[@B21]\]. In this review, old methods using classical instruments including Reverdin and Deschamps needles appeared to be cost effective and also useful as well as special wound devices designed for port site closure. Moreover, Elashry et al. and Nakada et al. showed in two randomized control studies that the Carter-Thomason device and the eXit puncture set both rated slightly higher than other devices; the Carter-Thomason device is also faster than all the tested techniques, results in lower port closure-related complications, and provides a leak-proof closure \[[@B21]--[@B23]\]. Insertion of a SURGICEL plug into the muscular layer of trocar wounds has also been proposed by Chiu et al. \[[@B24]\]. Alternatively, tangential insertion of a trocar through the abdominal wall might be effective in reducing the size of fascial defects \[[@B25], [@B26]\]. Moreover, different data from the literature have demonstrated that radially expanding type trocars could be useful to avoid the necessity of closing the fascial defect \[[@B27]\].

4. Conclusions {#sec4}
==============

Trocar site hernia (TSH) is one of the potentially severe complications of operative laparoscopy with large-bore trocar ports. TSH has been infrequently reported in the setting of two-trocar procedures but appears to be more common in operative procedures with multiple large bore ports, and it may occur at both umbilical and extraumbilical sites ([Table 3](#tab3){ref-type="table"}).

The incidence of TSH is lower than incisional hernias after open surgery, even if the actual incidence could be probably higher. Indeed, our literature review points out at least 14 reports of TSH whose incidence is not reported ([Table 1](#tab1){ref-type="table"}). Moreover, TSH was not listed or reported as a complication of laparoscopic surgery in several recent surveys. In addition, some patients, loss from followup is also to be considered, other patients may remain asymptomatic, while in other cases herniation might not be evident because of obesity. Besides all these underestimated cases, the incidence of TSH resulting from our review ranges from 0.007% to 22% ([Table 1](#tab1){ref-type="table"}) with an average of 1.85%.

The risk factors associated with the occurrence of TSH are related both to the patient\'s characteristics and the surgical technique. An important predisposing factor is obesity because of obese patients\' thicker peritoneum, but advanced age, gender, nutritional status, diabetes, anaemia, steroid therapy, renal insufficiency, cancer, and wound infections also contribute to the occurrence of TSH. Different factors related to the surgical technique may also increase the risk of herniation by widening the fascial defect, such as the use of "fascial screws\" to secure the port within the abdominal wall; longer procedures that result in excessive manipulation of port sites may also widen the fascial defect and increase the risk of herniation; large ports; cutting trocars; undetected omentum or bowel entrapment into the intraperitoneal defect after trocar removal; not sutured larger fascial defects ([Table 2](#tab2){ref-type="table"}).

Omental herniation, a type 3 complication according to the classification of Tonouchi, may be an expected postoperative complication of laparoscopic surgery for young children. In adult surgery incisions ≤ 5 mm are sometimes not sutured at all, as in infants they are only sutured by one cutaneous stitch. According to most of the authors, despite the evidence that some types of trocars prevent or are better at avoiding trocar site herniation, closure of both the fascia and the peritoneum of the site should be, however, recommended if the incision is greater than 7 mm in adult patients and ≥5 mm in young children.

Different authors believe that inserting the 10 mm lateral trocar in an oblique way or as a Z-tract will reduce hernia formation by placing the external and internal fascias at different levels; instead, according to recent reports, tangential insertion of a trocar through the abdominal wall might be effective in reducing the size of fascial defects making it easier to close the fascia and peritoneum at the same time.

Unfortunately, although properly currently performed, closure is not always completely protective. Prevention of extraumbilical incisional hernias and dehiscences appears to be more effective when suture is performed under laparoscopic vision keeping the trocar inserted. Moreover, both the aponeurosis and the peritoneal membrane should be treated as carefully as possible, and different methods or devices should be employed to simplify and minimize the risk of hernia formation.

A careful postoperative management is recommended especially for patients with risk factors such as obesity, extensive manipulation of the trocar, and longer procedures. Bowel occlusion clinical presentation is often insidious, as in the case of a partial Richter\'s hernia. When in laparoscopic surgery a resolution of postoperative ileus after a period of 7--14 days of medical therapy and observation is not obtained, a differential diagnosis between postoperative ileus and pathologic postoperative occlusions (trocar site hernia, adhesions) is to be assessed. In these patients observation alone could be not enough appropriated to perform a well-timed diagnosis, making abdominal CT still play a key role for a right differential diagnosis.

Authors\' Contributions {#sec5}
=======================

All authors contributed equally to this work.

![](SURGERY2011-725601.001){#fig1}

###### 

Trocar site hernia frequency.

                          Pub.   Patients undergoing VLS        Trocar site hernia/ Tot-VLS   TSH %
  ----------------------- ------ ------------------------------ ----------------------------- -------
  Fear                    1968   Gynaecological surgery         1/NS                          
  Schiff and Naftolin     1974   Gynaecological surgery         2/NS                          
  Mintz (Review)          1977   Abdominal surgery              7/100000                      0.007
  Bourke                  1977   Abdominal surgery              1/NS                          
  Sauer and Jarrett       1984   Diagnostic laparoscopy         1/NS                          
  Hogdall and Rosen       1987   Gynaecological surgery         1/NS                          
  Kiiholma, and Makinen   1988   Gynaecological surgery         1/NS                          
  Thomas et al.           1990   Abdominal surgery              1/NS                          
  Voyles                  1991   Cholecystectomy                1/500                         0.20
  Larson                  1992   Cholecystectomy                3/1983                        0.15
  Baird                   1992   Cholecystectomy                1/800                         0.13
  Kadar et al.            1993   Gynaecological surgery         4/NS                          
  Multicentrico           1993   Gynaecological surgery         6/3560                        0.17
  Multicentrico           1994   Gynaecological surgery         933/4.385.000                 0.021
  George                  1994   hysterectomy                   3/NS                          
  Multicentrico           1995   Gynaecological surgery         19/NS                         
  Le Bouëdec              1995   Hysterectomy                   1/NS                          
  Azurin                  1995   Cholecystectomy                10/1300                       0.77
  Mike et al.             1996   Pediatric surgery              2/574                         0.35
  Mayol                   1997   Abdominal surgery              6/403                         1.48
  Ahmad                   1997   Cholecystectomy                11/1300                       0.84
  Nassar                  1997   Cholecystectomy                16/870                        1.83
  Multicentric            1999   Gynaecological surgery         8/32.205                      0.025
  Sanz-Lopez              1999   Cholecystectomy                2/123                         1.62
  Berthou                 1999   Colectomy for diverticulitis   1/110                         0.90
  Eltabbakh               1999   Gynaecological surgery         1/NS                          
  Coda                    2000   Abdominal surgery              13/1287                       1
  Schauer                 2000   Gastric bypass                 1/257                         0.36
  Bowrey                  2001   Fundoplication                 9/320                         2.8
  Schmedt et al.          2001   Ventral hernia repair          301/6023                      4.99
  Berger et al.           2002   Incisional hernia repair       4/150                         2.66
  Al-Haijar               2002   Cholecystectomy                10/1453                       0.68
  Lumley                  2002   Colectomy for neoplasm         1/152                         0.65
  Dresel                  2002   Gastric banding                1/100                         1
  Susmallian,             2002   Gastric banding                3/459                         0.65
  Boughey et al           2003   Abdominal surgery              4/NS                          
  Immè, and Cardì F.      2006   Abdominal surgery              12/600                        2
  Boldó et al.            2007   Ventral hernia repair          6/27                          22.2
  ten Duis et al.         2008   Abdominal surgery              3/NS                          
  Paya et al.             2008   Pediatric surgery              8/293                         2.73
  Our experience          2009   Abdominal surgery              2/4387                        0.045

VLS: laparoscopy

###### 

Fascia closure.

  Report            Cases      Fascia closure   Year
  ----------------- ---------- ---------------- ------
  Kadar et al.      6          50%75%SBH        1993
  George            3          100%             1994
  Multicenter       933        17.9%            1994
  Multicenter       19         42%              1995
  Eltabbakh.        1 (5 mm)   0                1999
  Immè and Cardì.   12         100%             2006
  Our experience    2          0                2009

###### 

TSH review.

  --------------------------------------------------------------------------------------------------------
  Report                  Cases         Port size           Site          PO day   Lap/VLS   SBR    Year
  ----------------------- ------------- ------------------- ------------- -------- --------- ------ ------
  Schiff, Naftolin        2             NS                  Umb           17.5     2/0       100%   1974

  Bourke                  1             12 mm               Umb           13       1/0              1977

  Sauer, Jarret           1             NS                  Umb           54       1/0              1984

  Hogdall, and Rosen      1             12 mm               Umb           1        1/0       100%   1987

  Kiiholma, and Makinen   1             10 mm               Umb           5        1/0              1988

  Thomas et al.           1             NS                  Umb           2        1/0       100%   1993

  Kadar et al.            6             0.23% 10 mm\        Ex-Umb        5        4/2              1993
                                        3.1% 12 mm                                                  

  Kurtz et al.            1             12 mm               Ex-Umb        6        1/0              1993

  Montz                   850           \>10 mm (86.3%)\                                            
                                        8--10 mm (10.9%)\                                           
                                        \<8 mm (2.7%)                                               

  George                  3             12 mm               NS            2        0/3              1994

  Multicentric            21*(19+ 2)*   12 mm (61%)\        Umb (23.8)\   8.5      17/2      9.5%   1995
                                        11 mm (4.8%)\       Ex-Umb\                                 
                                        10 mm (47,7%)       (76.2%)                                 

  Le Bouëdec              1             12 mm               Ex-Umb        6        0/1              

  Eltabbakh.              1             5 mm                Ex-Umb        7        1/0              1999

  Multicentric            8             5 mm (12.5%)\       Umb           8        8/0       38%    1999
                                        10 mm (62.5%)\                                              
                                        12 mm (25%)                                                 

  Immè, and Cardi F       12            \>10 mm             Umb           NS       12/0             2000

  Our experience          2             12 mm               Ex-umb        12       2/0       50%    2009
  --------------------------------------------------------------------------------------------------------

LAP: laparotomy; VLS: laparoscopy.

SBR: small bowel resection.

Umb: Umbilical; Ex-Umb: extraumbilical.

[^1]: Academic Editors: A. Mansour and E. C. Tsimoyiannis
