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Table of Contents
ORIGINAL ARTICLES
Year : 2022  |  Volume : 5  |  Issue : 2  |  Page : 53-58

A novel hybrid approach to the repair of flank hernias


1 Department of Surgery, Division of General Surgery, Louisiana State University Health Science Center, New Orleans, USA
2 Department of Surgery, Surgeons Group of Baton Rouge, Our Lady of the Lake Physicians Group, Baton Rouge, Louisiana, USA
3 Department of Surgery, Division of General Surgery, Louisiana State University Health Science Center, New Orleans, USA; Department of Surgery, Surgeons Group of Baton Rouge, Our Lady of the Lake Physicians Group, Baton Rouge, Louisiana, USA

Date of Submission27-Oct-2021
Date of Acceptance16-Nov-2021
Date of Web Publication19-May-2022

Correspondence Address:
Brendan P Chou
Department of Surgery, Division of General Surgery, Louisiana State University Health Science Center, 5000 Hennessy Blvd, Baton Rouge, Louisiana 70808
USA
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijawhs.ijawhs_76_21

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  Abstract 

Background: Flank hernias are uncommon and challenging to repair. Discussion of flank hernia repair is scarce in the literature. We present a novel approach to repair flank incisional, traumatic, and denervation hernias with a “hybrid” approach using an open repair in conjunction with the robotic platform for laparoscopic intraperitoneal mesh fixation. Materials and Methods: A retrospective analysis was conducted on all patients who received a “hybrid” repair from April 2014 through January 2020 by a single surgeon. Patient and hernia characteristics, operative techniques, and outcomes were evaluated. Each patient underwent a similar operation with an intraperitoneal mesh as well as an onlay mesh. Minor technique changes including quilting and wound vac placement were developed and compared. Results: Twenty-five patients were included in the study. Outcomes analyzed included wound infection (8.0%), seroma formation (16.0%), hematoma formation (12.0%), mesh infection (0.0%), weight gain (16.0%), hernia recurrence (4.0%), reoperation (12.0%), and chronic pain (25.0%). Compared to the drain placement group, quilting of the subcutaneous tissue was more likely to result in seroma (17.6% vs. 12.5%, P = 0.618) and hematoma (17.6% vs. 0.0%, P = 0.296). Use of negative pressure incisional wound vac did not impact the incidence of wound infection (12.5% vs. 6.2%, P = 0.565), seroma (12.5% vs. 17.6%, P = 0.618), or hematoma formation (12.5% vs. 11.8%, P = 0.704). Conclusion: The “hybrid” repair represents a novel approach to flank hernias. Improved visualization of the intraperitoneal portions of the operation using the robotic platform allows for accurate mesh fixation. In experienced hands, this approach provides safe and satisfactory outcomes similar to a purely open repair.

Keywords: Denervation, flank hernia, hematoma, hybrid, lumbar hernia, robotic, seroma


How to cite this article:
Chou BP, Bentley K, LeBlanc KA. A novel hybrid approach to the repair of flank hernias. Int J Abdom Wall Hernia Surg 2022;5:53-8

How to cite this URL:
Chou BP, Bentley K, LeBlanc KA. A novel hybrid approach to the repair of flank hernias. Int J Abdom Wall Hernia Surg [serial online] 2022 [cited 2022 Jul 1];5:53-8. Available from: http://www.herniasurgeryjournal.org/text.asp?2022/5/2/53/345513




  Introduction Top


Flank and lumbar hernias represent a unique subset of hernias for both the patient and the operating surgeon. True lumbar hernias are congenital anatomic defects located in the superior (Grynfeltt) and inferior (Petit) lumbar triangles.[1],[2] These are traditionally approached from an open technique directly overlying the hernia with the patient prone or in a lateral recumbent position. More recent advances in laparoscopy and robotic surgery have allowed these defects to be repaired from a minimally invasive approach.[3],[4] Flank hernias, however, are defects in the lateral abdominal wall and may be classified as either primary (spontaneous) or secondary hernias with a true fascial defect.[5] Incisional hernias resulting from operations to the lateral retroperitoneum or back may result in a secondary hernia with a true fascial defect. Such operations include nephrectomy, open retroperitoneal aortic surgery, spinal surgery, or trauma.[6],[7] Denervation hernias represent spontaneous primary hernias and may result from injury to the nervous supply to the lateral abdominal wall, specifically the intercostal nerves of nerve roots T7–T12. This results in muscular atony and atrophy producing a bulge and asymmetric abdominal contour without a true fascial defect, often made worse with the Valsalva maneuver.[8],[9],[10] Flank hernias may additionally result from prior trauma in which the muscles have been torn from the iliac crest. Examples of this include motor vehicle accidents in which seatbelt injuries have resulted in flank hernias secondary to the shear stress of the lateral abdominal wall muscles tearing from the pelvic girdle.[7]

Patients with flank hernias, either incisional, traumatic, or denervation, suffer the same limiting functional impairments as patients with midline or anterior abdominal wall hernias. However, the approach to repair flank hernias must be necessarily different than anterior abdominal wall hernias due to the overlapping anatomic compartments involved in the hernia.[9] The need to dissect laterally into the retroperitoneal space requires the patient to be positioned appropriately in a partially decubitus position. Finally, the location for mesh placement must address the anatomy of the lateral abdominal wall and limitations provided by boney structures such as the iliac crest and the lower rib cage.[10]

Traditionally, these hernias have been repaired with a purely open approach with attempts made to stay extraperitoneal. A synthetic mesh is placed in the preperitoneal space extending to the retroperitoneum. The mesh is secured with trans-fascial sutures with or without the aid of bone anchors. The choice of onlay mesh or the need for muscle plication is individualized to the patient.[11],[12] Laparoscopic repairs have been developed for the secondary flank hernias as well as advances in technology allow for improved technique.[13],[14] Pure laparoscopic repairs suffer from the inability to easily plicate the muscles, making the recurrence of denervation hernias much more likely to recur. With the introduction of the robotic platform, larger and more complex defects are being successfully addressed.[15]

We present a novel approach in the repair of flank hernias, combining the traditional open approach with the robotic surgery platform to aid in mesh fixation. Here, we outline the “hybrid” surgical approach along with patient outcomes from one surgeon’s practice at a single institution beginning with the introduction of the robotic platform by the surgeon in April 2014 through January 2020.


  Materials and Methods Top


This was a single-center retrospective review of prospectively collected data. The Institutional Review Board at our institution approved the study. The requirement for informed consent was waived because of the retrospective nature of the study.

The study cohort comprised all patients who underwent the combination of an open and robotic surgical approach to repair the flank hernias performed by this surgeon from April 2014 through January 2020. Identified etiologies of flank hernia included true incisional flank hernias, denervation flank hernias, or traumatic flank hernias. Many of the incisional and traumatic patients had injuries to the nervous supply to the posterolateral muscles and therefore a denervation element to their hernia; however, they were categorized by their primary defect type. Patient risk factors for hernia complications included medical comorbidities, body mass index (BMI), smoking history, and surgical history.

Perioperative variables included defect size, type of intraperitoneal and onlay meshes used, use of subcutaneous drain placement, subcutaneous skin flap quilting, or negative pressure wound vac placement. Outcome variables included hospital length of stay, postoperative complications of seroma formation, hematoma formation, wound infection, mesh infection, persistent pain, and hernia recurrence through 1-year follow-up after surgery. The hospital length of stay was defined as the total number of nights spent in the hospital postoperatively. Chronic pain was defined as continuous pain for greater than 90 days after the operation. All patients were followed postoperatively in the outpatient clinic by the senior author.

Patient demographics, preoperative and perioperative characteristics, and postoperative complications were compared. Continuous variables were reported as mean ± standard deviation. Categorical variables were reported as count and percentage and were compared by using Pearson’s chi-square test or the Fisher exact test if expected counts were not sufficiently large. Test results were considered significant at P < 0.05. All analyses were performed with IBM SPSS Statistics software program, version 20.0 (Armonk, New York).

Operative technique

Patients were positioned in the operating room with a slight bump to the ipsilateral side of the hernia in a partially lateral decubitus position. The table was left flat with no flexion to avoid enlargement of the defect and eventual repair. Flexion would have resulted in laxity of the plicated musculature and was consistently avoided. The patient was prepped from above the costal margin to the pelvic brim. Universal drapes were used to provide maximum exposure. If a prior incision was present, it was used as the operative incision and extended as needed. If none was present, as in true denervation or traumatic hernias, an oblique incision was made along Langer’s lines. Skin flaps were raised, separating the subcutaneous tissue from the fascia. The hernia sac was then circumferentially dissected out, and the dissection was carried into the retroperitoneal space to the paraspinus muscles posteriorly. The peritoneal space was entered to accommodate robotic trocars. Adhesions were freed if present.

Mesh size was selected based on patient body habitus and defect size. A minimum overlap of 5 cm was felt to be inadequate in most cases. Our preference was to provide mesh overlap extending above the rib margin, into the pelvis, near or across the midline and over the quadratus lumborum and psoas muscles. The intraperitoneal mesh was always a coated synthetic macroporous midweight mesh, either polypropylene/carboxymethylcellulose/hyaluronic acid combination mesh (Ventralight ST, C.R. Bard/Davol, Warwick, Rhode Island) or polytetrafluoroethylene (PTFE)/trimethylene carbonate /polyglycolic acid combination mesh (Synecor IP, W.L. Gore & Associates, Newark, Delaware). This was fixed with three permanent Goretex (W.L. Gore & Associates) transfascial sutures along the center and at each apex of the mesh. The fascial and muscle layers were then closed and plicated if needed. An onlay mesh was placed, which consisted of either a macroporus polypropylene (Bard Soft mesh, C.R. Bard/Davol) or a combination PTFE mesh lined on both sides with trimethylene carbonate/ polyglycolic acid with bioabsorbable material (Synecor Pre, W.L. Gore & Associates). The skin flaps were closed with either a drain left in place in the subcutaneous space or by using a quilting technique with multiple double-armed 2-0 absorbable barbed suture to eliminate the dead space. Quilting the subcutaneous flaps to the underlying onlay mesh and fascia was a technique developed and adopted to reduce the need for drain placement and incidence of seroma formation. The robot was then docked, and the remainder of the intraperitoneal mesh was secured along its perimeter using a barbed polypropylene suture. This was done to ensure the mesh was in good contact with the abdominal wall and to maintain the flat shape of the mesh with the correct tautness. Sterile dressing or negative pressure therapy vacuum was then applied. The use of negative pressure wound vacuum was adopted later in the study. Patients then underwent routine postoperative care.

All operations were performed by a single surgeon in a single institution. Over the 6-year study period, there were some slight variations in operative technique including mesh selection, use of drains within the subcutaneous space versus the quilting technique, and use of negative pressure wound therapy. The variations represent slight improvements in the operation as the technique was modified based on prior outcomes and surgeon experience.


  Results Top


We identified 25 patients who underwent a hybrid repair of their flank hernia during the study period. Preoperative patient characteristics including demographics and comorbid conditions are shown in [Table 1]. We evaluated gender, age, smoking history, BMI, medical comorbidities, prior flank or abdominal operations, and prior hernia repairs. There was a slight predominance for patient’s being male (n = 13, 52%). The mean age was 58.8 ± 13 years old. Patients were predominantly white (n = 23, 92%). Mean BMI was 30–34 with 64% of patients overall having a BMI >30 and another 24% being overweight with a BMI between 25 and 29. Chronic pain was listed in the medical histories of 12 (48%) patients prior to surgery. Only 6 (24%) patients were diabetic. Most patients were never smokers (n = 15, 60%), whereas 10 (40%) were former smokers. All patients were made to stop smoking at least 4 weeks prior to operation. The majority of patients had prior operations (n = 23, 92%), either in the midline or flank. Seven (28%) had a prior hernia repair at the site. Eight (32%) patients had denervation type hernias without fascial defects identified intraoperatively.
Table 1: Demographic data

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Perioperative data are shown in [Table 2]. Hernia characteristics were compared as well as variations in operative technique. Etiology of the hernia was categorized into traumatic, denervation, or incisional. The majority of patients had incisional flank hernias (n = 18, 72%), whereas five (20%) patients had traumatic flank hernias and eight (32%) of patients had a component of denervation flank hernias. Defect size was measured for all hernias that were not purely denervation type. Defect size measured for each patient is shown in [Table 3]. Average defect length was 13.5 ± 6.5 cm, median (IQR) was 12 cm (11–15 cm), and average defect width was 12.3 ± 4.7 cm with median (IQR) of 15 cm (7.5–15 cm). Average defect size was 172.0 ± 109.9 cm2 with a median (IQR) of 150 cm2 (94.5–232.5 cm2). Mesh type and size were evaluated. All but three patients received a coated macroporus PTFE mesh (Synecor IP) as the intraperitoneal mesh. The remaining three patients received a coated polypropylene mesh. The onlay mesh was either an uncoated macroporus polypropylene mesh (Bard Soft) (n = 14, 56%) or a combination PTFE mesh (Synecore Pre) (n = 10, 40%). The mean length of hospital stay was 4.3 ± 1.1 days, with a median (IQR) of 4.0 days (4.0–5.0 days).
Table 2: Perioperative data

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Table 3: Defect size

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Intraoperative measurement of defect size is shown in [Table 3]. Postoperative outcomes and complications are shown in [Table 4]. These include analysis of wound infection, seroma, hematoma, mesh infection, weight gain, hernia recurrence, reoperation, and chronic pain. Patients were followed up at scheduled clinic appointments at 1, 3, 6, and 12 months as possible. Mean length of postoperative follow-up was 144.2 ± 120.2 days, median (IQR) 124.0 days (68.0–195.0 days).
Table 4: Postoperative complications

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The most common postoperative complication requiring intervention was the development of a seroma (n = 4, 16%) or hematoma (n = 3, 12%). Most of these were treated with percutaneous drain placement or ultrasound (US)-guided aspiration. Two were observed with eventual resolution. Two patients required evacuation of the seroma or hematoma in the operating room after failed resolution with drain placement. When compared to the drain placement group, quilting of the subcutaneous tissue had a greater incidence of postoperative seroma formation (17.6% vs. 12.5%, P = 0.618) and hematoma formation (17.6% vs. 0.0%, P = 0.296), although this did not reach statistical significance. Wound infections were found in only 2 (8%) patients, both of which also had underlying seromas.

The use of negative pressure wound therapy did not impact the incidence of wound infection (12.5% vs. 6.2%, P = 0.565), seroma (12.5% vs. 17.6%, P = 0.618), or hematoma formation (12.5% vs. 11.8%, P = 0.704) when compared to no incisional wound vacuum placement. No patients developed a mesh infection. Persistent pain as defined as pain at the prior hernia site persisting for over 3 months postoperatively was present in 5 (20.0%) patients. No significant difference in persistent pain was found between the drain and quilting groups. Hernia recurrence occurred in only 1 (4%) patient. This patient had a fall 1 year after index operative repair and experienced pain along the right flank. Computed tomography (CT) imaging indicated recurrent mesenteric fat herniation. The patient returned to the operating room for an entirely open repair and was found to have hernia recurrence posterior to the prior repair. This was repaired with intraabdominal 15 cm × 20 cm Synecor IP and 20 cm × 25 cm Synecor Pre onlay mesh. The second operation was complicated by seroma formation requiring operative drainage 3 weeks postoperatively. This patient fell again a year after the second repair and was noted to have another recurrence, after which the patient declined repeat operative intervention and opted to observe the hernia.


  Discussion Top


The goal of this study was to show the safety and efficacy of a novel open surgical approach combined with a robotic approach to flank hernia repair. Flank hernias represent a unique challenge to the hernia surgeon. Although traditional lumbar and small incisional flank hernias may best be approached with a purely minimally invasive technique, the large incisional and denervation flank hernias are better suited for this hybrid approach as described here. Muscle plication and reinforcement with both an underlay and onlay mesh provide the maximum support for patients with a weakened lateral abdominal wall. The ability to use the robotic platform to firmly stretch the intraperitoneal mesh ensures maximum contact between the mesh and fascia promoting tissue ingrowth and proper positioning of the mesh material.

Not surprisingly, seromas (n = 4, 16.0%) and hematomas (n = 3, 12.0%) were the most common complication following these large repairs. Our rate is comparable with large studies of seroma or hematoma formation following large hernia repairs requiring musculocutaneous flap creation.[16],[17] The incidence of seroma (17.6% vs. 12.5%, P = 0.618) or hematoma (17.6% vs. 0.0%, P = 0.296) was greater when using the quilting technique to close the dead space than with the use of drains, although this did not reach statistical significance. This was not an anticipated outcome, as the quilting technique had been adopted for anterior abdominal wall reconstruction cases with good results in our practice as well as being well-described in the literature.[18] Anatomic variations may account for this difference; however, further comparative studies may need to be developed to understand the significance of this finding. Every effort should be made to reduce the formation of seromas or hematomas as they can be a source of pain to the patient and inhibit mesh incorporation into the tissue.[16] Our preferred method of treatment was US-guided aspiration or placement of percutaneous drain by interventional radiology. These drains were subsequently removed after a short time interval.

The only two wound infection complications occurred in patients who had a concomitant underlying seroma. Both patients ultimately required debridement of skin and subcutaneous tissue in the operating room to evacuate the seroma and debride the skin flaps with placement of drains. One patient had received a negative pressure wound vacuum at the initial operation, and the other did not. Given the small number of wound infections and small case series, no significant difference was found with the use of incisional wound vacs compared to sterile dressing alone. The use of incisional wound vacs, however, is well-supported in the surgical literature and a larger study would help elucidate their impact in our institution.[19],[20]

Hernia recurrence at any site is one of the most disappointing complications for any hernia surgeon. Every effort should be made to reduce modifiable risk factors in the preoperative workup period such as weight loss, smoking cessation, and glycemic control. The perioperative period should be optimized as well by following appropriate antibiotic guidelines, avoiding enterotomies, and ensuring adequate tissue perfusion to skin flaps. Enhanced Recovery after Surgery (ERAS) programs have been developed at high-volume centers to aid in patient recovery and reduce hospital lengths of stay.[21],[22] In our study, only one recurrence was reported. The particular patient was a multiply-recurrent hernia patient, and the decision was made to observe the recurrence rather than attempt reoperation at this point. One of the other issues that are seen with other methods of repair of these hernias with the single approach is the persistence of a bulge. This cosmetic deformity is unacceptable to most patients. Although this did occur to a very limited extent in a few patients, all patients felt that their appearance was markedly improved to the preoperative appearance. The lone exception is the individual that developed a recurrence.

This was a single-center retrospective study and subject to several limitations, including selection bias. In addition, the small number of cases limits the utility of statistical analysis and the generalizability of the findings. Further studies are needed, and a larger patient database may compensate for the rarity of patients who present with these uncommon flank hernias. A larger patient cohort may help elucidate the best method of treating these complicated hernias as well as refining intraoperative techniques.


  Conclusion Top


In summary, we show a “hybrid” repair approach as a novel approach to flank hernias. In experienced hands, patient outcomes and satisfaction are similar to a purely open repair. However, there does appear to be better cosmesis with this hybrid approach with the use of two meshes placed in different planes of tissue. Improved visualization of the intraperitoneal portions of the operation makes this repair unique and presents an innovative use of currently available technology.

Financial support and sponsorship

Nil.

Conflicts of interest

Dr. Karl LeBlanc is on the Speakers Bureau of W.L. Gore & Associates and BD Interventional.

Dr. Karl LeBlanc is an Associate Editor of International Journal of Abdominal Wall and Hernia Surgery. The article was subject to the journal’s standard procedures, with peer review handled independently of this Editor and their research groups.



 
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    Tables

  [Table 1], [Table 2], [Table 3], [Table 4]



 

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