# Incidence and risk factors for recurrence of incisional hernia repair after liver transplantation: a retrospective cohort study

Edouard Wasielewski<fnref n="1" />☐, Thierry Pecot<fnref n="2" />, Estelle Le Pabic<fnref n="3" />, Mohamed Lakehal<fnref n="1" />, Astrid Herrero<fnref n="4" />, Fabien Robin<fnref n="1" />, Karim Boudjema<fnref n="1" />, Laurent Sulpice<fnref n="1" />,<fnref n="5" />

Received: 3 March 2025 / Accepted: 2 June 2025

© The Author(s) 2025

## Abstract

**Purpose** The objective of this study was to evaluate the incidence and identify risk factors associated with the recurrence of incisional hernia (IH) following initial parietal repair in patients who had undergone liver transplantation. Liver transplantation (LT) is a complex procedure associated with numerous complications, particularly those affecting the abdominal wall, with incisional hernia (IH) being the most significant. To date, the risk factors contributing to IH recurrence in this population have not been systematically assessed.

**Methods** This retrospective, single-center study included all patients who underwent liver transplantation at Rennes University Hospital between January 1, 2012, and December 31, 2018. The list of eligible patients was provided by the French Biomedicine Agency.

**Results** A total of 803 liver transplant recipients were included. Among them, 282 patients (35.1%) developed an incisional hernia (IH) after a median follow-up of 75.87 months [54.7–97.2]. Of these, 50 patients (35.4%) experienced IH recurrence at a median interval of 8.8 months [5.2–34.2] following primary repair. Identified risk factors for recurrence included: length of hospital stay after the initial repair (HR: 1.09 [1.09–1.13], P=<0.0001), type of repair (suture versus prosthetic) (HR: 2.48 [1.25–4.9], P=0.009). Visceral obesity is considered a high-risk factor (HR: 2.21 [0.98–4.95], P=0.055), although the association no longer reached the conventional threshold for statistical significance.”

**Conclusion** To the best of our knowledge, this is the first study to assess body composition as a risk factor for incisional hernia recurrence in the liver transplant population. These findings highlight the importance of considering visceral obesity as a significant predictor of recurrence.

**Keywords** Liver transplantation · Recurrence · Incisional hernia · Skeletal muscle index

## Introduction

Liver transplantation (LT) remains a critical intervention for patients with advanced liver disease. Despite significant medical and surgical advances, postoperative complications are frequent, among which incisional hernias (IH) are notably prevalent. IH, defined as a defect in the abdominal wall at the site of a previous surgical incision, affects up to 35.6% of the general population [1], with reported incidence rates ranging from 1.7 to 43% in liver transplant recipients [2]. In addition to well-established risk factors [3–5], several other variables—including advanced age [6], a history of pulmonary disease [2], incision type [7], diabetes mellitus [8], and immunosuppressive therapy [9]—have been implicated in the development of IH within this specific patient population.

<figure><img src="image_1.png" /></figure>

<footnote>Laurent Sulpice
Laurent.sulpice@chu-rennes.fr</footnote>

<footnote n="1">¹ Department of Hepatobiliary and Digestive Surgery, University Hospital, Rennes 1 University, Rennes, France</footnote>

<footnote n="2">² University of Rennes, Biosit UAR 3480 CNRS– US 018 Inserm, FAIIA core facility, Rennes F-35000, France</footnote>

<footnote n="3">³ Department of Clinical PharmacologyUniversity Hospital, Rennes 1 University, Rennes, France</footnote>

<footnote n="4">⁴ Department of HBP Surgery & Transplantation, St-Eloi University Hospital, Montpellier, France</footnote>

<footnote n="5">⁵ Department of Digestive Surgery, CHU Rennes 35 000, Pontchaillou Hospital, Rennes 1 University, Rennes, France</footnote>
Assessment of nutritional status, particularly body com-
position, is of critical importance in the management of
patients both before and after liver transplantation [10].
Sarcopenia—defined by the European Working Group on
Sarcopenia in Older People (EWGSOP) as a loss of muscle
mass associated with adverse outcomes such as falls, frac-
tures, and increased mortality [11]—is highly prevalent
among individuals with cirrhosis [12] and tends to worsen
with disease progression [13]. Moreover, obesity, frequently
coexisting with sarcopenia in the form of sarcopenic obe-
sity, has been identified as a prognostic factor for post-trans-
plant mortality [14].

Body composition can be assessed using various tech-
niques, including dual-energy X-ray absorptiometry
(DEXA) and computed tomography (CT). Although DEXA
is considered the gold standard, CT scanning offers a faster
and more widely accessible means of evaluating both sarco-
penia and visceral obesity in patients awaiting liver trans-
plantation [15].

The aim of the present study was to identify prognostic
factors associated with the recurrence of incisional hernia
following liver transplantation. We hypothesized that both
sarcopenia and visceral obesity contribute to an increased
risk of recurrence.

Patients and methods

Study design

We conducted a retrospective analysis of all adult patients
who underwent liver transplantation at Rennes Univer-
sity Hospital between January 1, 2012, and December 31,
2018. The list of transplant recipients was obtained from the
French Biomedicine Agency. All surviving patients were
informed of the study and provided their consent to partici-
pate. The study was conducted in accordance with the ethi-
cal principles outlined in the 2013 declarations of Helsinki
and Istanbul, and received approval from the Ethics Com-
mittee of Rennes University Hospital (No. 25.21).

Patients

Data prospectively collected by the Biomedicine Agency up
to the time of liver transplantation included demographic
and anthropometric characteristics (age, sex, weight, height,
body mass index [BMI]), medical history, etiology of liver
disease, and the severity of cirrhosis as assessed by both the
Child-Pugh-Turcotte score and the Model for End-Stage
Liver Disease (MELD) score. Additional data, retrospec-
tively obtained from patients' medical records, included
smoking status, pre-transplant serum albumin levels,

treatments received prior to transplantation (e.g., chemo-
therapy, radiotherapy, microwave ablation), and any history
of liver surgery (including hepatectomy and atypical resec-
tions) prior to transplantation.

Incisional hernia or recurrence

The diagnosis of incisional hernia (IH) or its recurrence was
made clinically and confirmed by contrast-enhanced com-
puted tomography (CT) in cases of diagnostic uncertainty,
particularly in obese patients. Indications for IH repair
included aesthetic discomfort, pain, or impaired ability to
resume physical activity. No emergency surgeries were per-
formed for hernia strangulation. Collected data included
the date of onset, anatomical location, type of surgical
repair, and postoperative complications occurring within 30
days. Complications were classified according to the Cla-
vien-Dindo system, with severe complications defined as
grade > IIIa [16]. Surgical repair consisted of either simple
suture or mesh placement, depending on the size of the her-
nia and the local risk of infection.

Evaluation of muscle and adipose mass

Automation of measurement

Evaluation of muscle and adipose tissue mass was con-
ducted using the most recent computed tomography (CT)
scan performed within 90 days prior to liver transplantation.
Analysis was based on a single axial slice at the level of
the third lumbar vertebra (L3). Tissue differentiation was
performed using Hounsfield unit (HU) thresholds: -29 to
+150 HU for skeletal muscle [17], and -190 to -30 HU for
adipose tissue [15]. The skeletal muscle area, normalized to
the square of the patient's height, was used to calculate the
Skeletal Muscle Index (SMI). Thresholds defining sarcope-
nia were set at <38.5 cm²/m² for females and <52.4 cm²/m²
for males [18]. Visceral obesity, assessed via Visceral Fat
Area (VFA), was defined by a threshold of >100 cm² for
both sexes [19]. Subcutaneous fat was measured as Subcu-
taneous Fat Area (SFA), expressed in cm²; in the absence of
established cut-off values, raw data were used for analysis.

The segmentation protocol and automation process for
measurement have been previously described [20]. The
complete software and accompanying video tutorials are
available at: https://github.com/tpecot/MuViSS.

Statistical analysis

In this study, quantitative variables are presented as
mean ± standard deviation or as median with interquartile
ranges (Q1–Q3), while qualitative variables are expressed as percentages. Time to first incisional hernia (IH) was calculated from the date of liver transplantation, and time to recurrence from the date of initial hernia repair. Patients who did not have a recurrence during the study period were considered as censored at the time of their last follow-up visit. Recurrence-free survival was defined as the interval between the date of the first IH repair and the date of recurrence, and was estimated using the Kaplan–Meier method. Variables potentially associated with recurrence were first assessed through univariate analysis. Variables with a significance level of *P*<0.20 were included in a Fine and Gray subdistribution hazards model to appropriately account for competing risks. Stepwise backward selection was then applied to identify independent predictors of recurrence. Statistical significance was set at *P*<0.05. All statistical analyses were performed using SAS software, version 9.4® (SAS Institute Inc., Cary, NC, USA).

## Results

Between January 1, 2012, and December 31, 2018, 804 patients underwent LT at the University Hospital of Rennes, and 803 were selected for this study. One transplant patient who remained in the department for more than two years for administrative reasons was excluded given that he was not subject to the same risks as transplant patients who returned to life outside the hospital. Of the 803 transplanted patients and after a median follow-up of 75.87 months (IQR 54.7–97.2), 35.1% (n=282) developed a first IH. The median time of occurrence of this first IH was 10.2 months (IQR 5.0–23.6). Of the 282 transplant recipients who developed IH, 50% (n=141) underwent open surgical repair. The median time from diagnosis to repair was 10.8 months (IQR 4.6–15.3). Of the 141 graft recipients who received open surgical repair of the IH, 35.4% (n=50) presented recurrence. The median time from repair of the first IH to recurrence was 8.8 months ((IQR 5.2–34.2). Of the 50 transplant recipients who redeveloped a recurrence, 54% (n=28) had a redo repair. The median time from recurrence to repair was 5.33 months (IQR 3.0–8.0). Table 1 reports the characteristics of the patients in the study population according to whether or

<table><caption>**Table 1** Characteristics of patients treated for a first IH</caption><thead><tr><th rowspan="2">Variable</th><th rowspan="2">Global</th><th colspan="2">Recurrence</th><th rowspan="2">HR [IC95%]</th><th rowspan="2">P-value</th></tr><tr><th>No</th><th>Yes</th></tr></thead><tbody><tr><td><strong>Age, median (years)</strong></td><td>60.0 [51.0–64.0]</td><td>60.0 [51.0–64.0]</td><td>60.5 [51.0–63.0]</td><td>0.99 (0.9; 1.0)</td><td>0.59</td></tr><tr><td><strong>Sex, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.13</td></tr><tr><td>Female</td><td>16 (11.3%)</td><td>13 (14.3%)</td><td>3 (6.0%)</td><td>1</td><td></td></tr><tr><td>Male</td><td>125 (88.7%)</td><td>78 (85.7%)</td><td>47 (94.0%)</td><td>2.47 (0.8; 7.9)</td><td></td></tr><tr><td><strong>BMI, median (kg/m²)</strong></td><td>27.1 [24.6–30.5]</td><td>26.26 [23.9–29.3]</td><td>28.29 [25.9–32.3]</td><td>1.08 (1.0; 1.1)</td><td>0.006</td></tr><tr><td><strong>Tobacco use, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.21</td></tr><tr><td>No</td><td>36 (28.8%)</td><td>21 (25.3%)</td><td>15 (35.7%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>89 (71.2%)</td><td>62 (74.7%)</td><td>27 (64.3%)</td><td>0.67 (0.4; 1.3)</td><td></td></tr><tr><td><strong>Diabetes, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.94</td></tr><tr><td>No</td><td>105 (74.5%)</td><td>68 (74.7%)</td><td>37 (74.0%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>36 (25.5%)</td><td>23 (25.3%)</td><td>13 (26.0%)</td><td>0.98 (0.5; 1.8)</td><td></td></tr><tr><td><strong>Albumin before LT median (g/dL)</strong></td><td>33.8 [29.2–39.0]</td><td>32.9 [29.3–38.2]</td><td>36.0 [28.2–39.5]</td><td>1.01 (0.9; 1.1)</td><td>0.55</td></tr><tr><td><strong>Etiology</strong></td><td></td><td></td><td></td><td></td><td>0.90</td></tr><tr><td>Alcohol</td><td>44 (31.2%)</td><td>15 (30.0%)</td><td>29 (31.9%)</td><td>1</td><td></td></tr><tr><td>Dysmetabolic cirrhosis</td><td>1 (0.7%)</td><td>0 (0.0%)</td><td>1 (1.1%)</td><td>0.7 (0.1; 12.9)</td><td></td></tr><tr><td>Mixed cirrhosis</td><td>9 (6.4%)</td><td>3 (6.0%)</td><td>6 (6.6%)</td><td>0.96 (0.3; 3.2)</td><td></td></tr><tr><td>Viral</td><td>6 (4.3%)</td><td>3 (6.0%)</td><td>3 (3.3%)</td><td>1.57 (0.5; 5.2)</td><td></td></tr><tr><td>HCC</td><td>66 (46.8%)</td><td>25 (50.0%)</td><td>41 (45.1%)</td><td>1.09 (0.6; 2.1)</td><td></td></tr><tr><td>Other</td><td>15 (10.6%)</td><td>4 (8.0%)</td><td>11 (12.1%)</td><td>0.66 (0.2; 2.0)</td><td></td></tr><tr><td><strong>MELD, median</strong></td><td>17.0 [9.50–24.0]</td><td>17.0 [9.0–24.5]</td><td>17.0 [10.0–24.0]</td><td>1.00 (0.9; 1.0)</td><td>0.86</td></tr><tr><td><strong>Surgery before LT</strong></td><td></td><td></td><td></td><td></td><td>0.06</td></tr><tr><td>No</td><td>103 (73.0%)</td><td>32 (64.0%)</td><td>71 (78.0%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>38 (27.0%)</td><td>18 (36.0%)</td><td>20 (22.0%)</td><td>1.72 (0.9; 3.1)</td><td></td></tr><tr><td><strong>IS≥2, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.70</td></tr><tr><td>Yes</td><td>118 (88.1%)</td><td>39 (86.7%)</td><td>79 (88.8%)</td><td>1</td><td></td></tr><tr><td>No</td><td>16 (11.9%)</td><td>6 (13.3%)</td><td>10 (11.2%)</td><td>0.85 (0.4; 2.0)</td><td></td></tr></tbody></table>

BMI: Body mass index– HCC: Hepatocellular Carcinoma– HR: Hazard Ratio - IS: immunosuppressors - LT: Liver transplantation– MELD: Model for End-Stage Liver Disease
<table><caption>**Table 2** Characteristics of first parietal repair</caption><thead><tr><th rowspan="2">Variable</th><th rowspan="2">Global</th><th colspan="2">Recurrence</th><th rowspan="2">HR [IC95%]</th><th rowspan="2">P-value</th></tr><tr><th>No</th><th>Yes</th></tr></thead><tbody><tr><td><strong>Localisation, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.07</td></tr><tr><td>Double</td><td>12 (8.5%)</td><td>7 (7.7%)</td><td>5 (10.0%)</td><td>1</td><td></td></tr><tr><td>Junction</td><td>12 (8.5%)</td><td>5 (5.5%)</td><td>7 (14.0%)</td><td>1.74 (0.6; 5.5)</td><td></td></tr><tr><td>Transversal</td><td>33 (23.4%)</td><td>21 (23.1%)</td><td>12 (24.0%)</td><td>0.71 (0.3; 2.0)</td><td></td></tr><tr><td>Vertical</td><td>84 (59.6%)</td><td>58 (63.7%)</td><td>26 (52.0%)</td><td>0.57 (0.2; 1.5)</td><td></td></tr><tr><td><strong>Type of repair, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.02</td></tr><tr><td>Prothesis</td><td>101 (73.7%)</td><td>70 (80.5%)</td><td>31 (62.0%)</td><td>1</td><td></td></tr><tr><td>Suture</td><td>36 (26.3%)</td><td>17 (19.5%)</td><td>19 (38.0%)</td><td>1.91 (1.1; 3.4)</td><td></td></tr><tr><td><strong>Localisation of prothesis, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.51</td></tr><tr><td>Intraperitoneal</td><td>65 (64.4%)</td><td>41 (58.6%)</td><td>24 (77.4%)</td><td>1</td><td></td></tr><tr><td>Retromuscular</td><td>36 (35.6%)</td><td>29 (41.4%)</td><td>7 (22.6%)</td><td>0.76 (0.3; 1.7)</td><td></td></tr></tbody></table>

HR: Hazard Ratio

<table><caption>**Table 3** Post-operative complication</caption><thead><tr><th rowspan="2">Variable</th><th rowspan="2">Global</th><th colspan="2">Recurrence</th><th rowspan="2">HR [IC95%]</th><th rowspan="2">P-value</th></tr><tr><th>No</th><th>Yes</th></tr></thead><tbody><tr><td><strong>Complication, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.17</td></tr><tr><td>No</td><td>82 (62.6%)</td><td>56 (67.5%)</td><td>26 (54.2%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>49 (37.4%)</td><td>27 (32.5%)</td><td>22 (45.8%)</td><td>1.49 (0.8; 2.6)</td><td></td></tr><tr><td><strong>Clavien-Dindo score, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.54</td></tr><tr><td>I</td><td>61 (48.8%)</td><td>42 (53.2%)</td><td>19 (41.3%)</td><td>1</td><td></td></tr><tr><td>II</td><td>42 (33.6%)</td><td>26 (32.9%)</td><td>16 (34.8%)</td><td>1.39 (0.7; 2.7)</td><td></td></tr><tr><td>IIIa</td><td>0 (0%)</td><td>0 (0.0%)</td><td>0 (0.0%)</td><td></td><td></td></tr><tr><td>IIIb</td><td>17 (13.6%)</td><td>8 (10.1%)</td><td>9 (19.6%)</td><td>1.66 (0.8; 3.7)</td><td></td></tr><tr><td>IVa</td><td>4 (3.2%)</td><td>2 (2.5%)</td><td>2 (4.3%)</td><td>1.80 (0.4; 7.8)</td><td></td></tr><tr><td>IVb</td><td>0 (0.0%)</td><td>0 (0.0%)</td><td>0 (0.0%)</td><td></td><td></td></tr><tr><td>V</td><td>1 (0.8%)</td><td>1 (1.3%)</td><td>0 (0.0%)</td><td></td><td></td></tr><tr><td><strong>Re-intervention, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.32</td></tr><tr><td>No</td><td>97 (82,2%)</td><td>63 (85,1%)</td><td>34 (77,3%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>21 (17,8%)</td><td>11 (14,9%)</td><td>10 (22,7%)</td><td>1.67 (0.6; 4.9)</td><td></td></tr><tr><td><strong>Ablation of prothesis, N (%)</strong></td><td></td><td></td><td></td><td></td><td>0.01</td></tr><tr><td>No</td><td>87 (91.6%)</td><td>58 (96.7%)</td><td>29 (82.9%)</td><td>1</td><td></td></tr><tr><td>Yes</td><td>8 (8.4%)</td><td>2 (3.3%)</td><td>6 (17.1%)</td><td>2.99 (1.2; 7.2)</td><td></td></tr><tr><td><strong>Hospital stay, median (days)</strong></td><td>8.0 [6.0–12.0]</td><td>7.5 [6.0–10.0]</td><td>9.0 [7.0–15.0]</td><td>1.08 (1.0; 1.1)</td><td>&lt;0.001</td></tr></tbody></table>

HR: Hazard Ratio

not they developed recurrence. Only the BMI (28.3 (IQR 25.9–32.3) vs. 26.26 (IQR 23.9–29.3) (P value=0.006) was significantly higher in the group of patients who presented recurrence. There was no other significant difference between the 2 groups. The cumulative incidence without IH and the cumulative incidence without recurrence as a function of time are shown in the supplementary data (Fig. S1).

The anatomic characteristics of the first IH are represented in Table 2. Recurrences were more frequent in transplant recipients whose first IH was repaired by running suture.

The rate and severity of complications that occurred after the first IH repair according to whether the grafters recurred or not are reported in Table 3. Postoperative complications as well as their severity did not influence recurrence. Recurrence of IH was significantly associated with the risk of removal of the mesh (6 (17.1%) vs. 2 (3.3%) (P value=0.02) as well as with an increase in the median

length of hospital stay (9.0 (IQR 7.0–15.0) vs. 7.5 (IQR 6.0–10.0) (P value<0.0001).

Body composition represented by muscle mass and parietal or visceral fat mass according to whether IH recurred or not are reported in Table 4. In our study, the rate of sarcopenic patients was not statistically different between the 2 groups. The VFA (207.0 (IQR 118.0–284.0) vs. 145.0 (IQR 86.5–220.5)) (P value=0.03) and the presence of visceral obesity (37 (84.1%) vs. 57 (69.5%)) (P value=0.0384) were significantly higher in the group of patients with recurrence. Parietal fat mass, represented by SFA, was not significantly different between the 2 groups.

The search for independent predictive factors for recurrence after a first cure is reported in Table 5. The length of hospital stay after surgical cure of the IH (HR: 1.09 (95% CI 1.06; 1.13)), running suture to repair a first IH (HR: 2.5 (95% CI 1.3; 4.9)). Although visceral obesity did not reach statistical significance in the multivariable model (HR:
<table><caption>**Table 4** Body composition of patients with an IH</caption><thead><tr><th rowspan="2">Variable</th><th rowspan="2">Global</th><th colspan="2">Recurrence</th><th rowspan="2">HR [IC95%]</th><th rowspan="2">P-value</th></tr><tr><th>No</th><th>Yes</th></tr></thead><tbody><tr><td><strong>Visceral obesity, N (%)</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>94 (74.6%)</td><td>57 (69.5%)</td><td>37 (84.1%)</td><td>1</td><td>0.03</td></tr><tr><td>No</td><td>32 (25.4%)</td><td>25 (30.5%)</td><td>7 (15.9%)</td><td>2.36 (1.1; 5.3)</td><td></td></tr><tr><td><strong>Sarcopenia, N (%)</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>Yes</td><td>55 (43.7%)</td><td>36 (43.9%)</td><td>19 (43.2%)</td><td>1</td><td>0.97</td></tr><tr><td>No</td><td>71 (56.3%)</td><td>46 (56.1%)</td><td>25 (56.8%)</td><td>1.01 (0.6; 1.8)</td><td></td></tr><tr><td><strong>SFA, median (cm²)</strong></td><td>55.1<br/>[36.6–85.91]</td><td>52.6<br/>[34.1–85.9]</td><td>59.7<br/>[38.9–88.8]</td><td>1.00 (0.9; 1.0)</td><td>0.55</td></tr></tbody></table>

HR: Hazard Ratio - SFA: Subcutaneous Fat Area - SMI: Skeletal Muscle Index - VFA: Visceral Fat area

<table><caption>**Table 5** Independent prognostic factors for recurrence with the fine and Gray competing risks regression model</caption><thead><tr><th>N</th><th>Variable</th><th>HR [95%CI]</th><th>P-value</th></tr></thead><tbody><tr><td>113</td><td></td><td></td><td></td></tr><tr><td></td><td>Length of stay</td><td>1.09 [1.06; 1.13]</td><td>&lt;0.0001</td></tr><tr><td></td><td>Type of repair</td><td>2.48 [1.25; 4.90]</td><td>0.0091</td></tr><tr><td></td><td>Visceral obesity</td><td>2.21 [0.98; 4.95]</td><td>0.0553</td></tr></tbody></table>

HR: Hazard Ratio

2.21(95% CI: 0.98;4.95), the strength and consistency of the association suggest a strong trend toward increased risk.

Discussion

Incisional hernia (IH) is a common and serious complication following liver transplantation (LT), often causing pain and discomfort during physical activity and carrying a potential risk of strangulation. Surgical repair is generally recommended, regardless of the technique or surgical approach employed.

In this retrospective, single-center study, we observed a high incidence of IH, affecting more than one-third of transplant recipients. Our findings are consistent with the existing literature, particularly the review conducted by *Garmpis et al.* [21]. It is noteworthy that only half of the initial hernias were repaired—primarily based on patient preference—and that the recurrence rate was comparable to the rate of initial occurrence. The repair rate observed in this study was slightly higher than that reported in the literature, which ranges from 39.4 to 43% [22, 23]. However, the recurrence rate observed in this study was slightly higher than that reported in the literature, which ranges from 3.4 to 25% [24, 25]. Several factors were found to be associated with a two- to three-fold increased risk of recurrence, including the use of simple suture repair and the presence of visceral obesity. Additionally, prolonged hospitalization following the initial repair further heightened this risk. Although sarcopenia is often regarded as an indirect marker of malnutrition, it was not associated with an increased risk of recurrence in our analysis.

To our knowledge, this is the first study to assess body composition in cases of recurrent incisional hernia (IH) following surgical repair in liver transplant recipients. As a preliminary observation, our findings suggest that all IHs—including recurrences—should ideally be managed with mesh placement, in accordance with established recommendations for the general population. Nevertheless, the use of a foreign body, such as a prosthetic mesh, in immunocompromised patients raises concerns regarding the risk of infection. Historically, this has contributed to hesitancy surrounding mesh implantation in transplant recipients. However, evidence from the literature does not indicate an increased risk of complications—particularly infections— in this population especially when the repair is performed laparoscopically [26].

In this study, body composition—including skeletal muscle mass index (SMI), subcutaneous fat area (SFA), and visceral fat area (VFA)—was evaluated using an automated method based on artificial intelligence (deep learning) applied to computed tomography (CT) scan data. This approach has demonstrated greater accuracy than body mass index (BMI) in assessing undernutrition [27]. It is well established that muscle mass plays a critical role in the success of liver transplantation [28]. To our knowledge, this is the first study to investigate the relationship between visceral and subcutaneous fat mass and the recurrence of incisional hernia (IH) using this advanced methodology.

Sarcopenia is highly prevalent among patients with advanced chronic liver disease awaiting transplantation, with an estimated prevalence of approximately 40% [18]. It has been associated with an increased risk of postoperative complications and mortality [29]. However, there is currently no universally accepted definition of sarcopenia based on the skeletal muscle mass index (SMI), resulting in substantial heterogeneity across existing studies, as underscored in the meta-analysis by *van Vugt et al.* [30]. Contrary to expectations, our analysis did not reveal a significant association between the presence of sarcopenia and the recurrence of incisional hernia (IH).

Incisional hernia (IH) occurred in nearly one-third of liver transplant recipients—a significantly higher rate than
that observed in the non-transplanted population [31]. How-
ever, this comparison is limited by differences in follow-up
protocols and surgical techniques between the two groups.
Moreover, the elevated recurrence rate observed in our
study may, in part, be attributable to the higher rate of her-
nia repair in this population. While *Bosanquet et al.* report
a repair rate of only 5.6% in the general population [1], our
cohort exhibited a rate of 50%. A higher rate of surgical
intervention inherently increases the likelihood of recur-
rence. The recurrence rate in our study (36.5%) exceeds that
reported in the existing literature [25, 32, 33]. This elevated
rate may be explained, in part, by the duration of follow-up.
According to *Smith et al.*, the risk of developing an inci-
sional hernia can persist for up to 12 years following liver
transplantation [34]. In our cohort, the median follow-up
period was 6.5 years. This follow-up was conducted alter-
nately by the hepatology and surgical teams, which likely
contributed to more accurate detection of hernias. In our
view, this multidisciplinary surveillance minimizes the risk
of diagnostic bias.

The method of fascial closure may also influence the incidence of incisional hernia (IH). At our center, closure is performed using a continuous suture technique: a median suture is applied to the vertical portion, while a three-layer closure is employed for the transverse segment. *Deerenberg et al.* have demonstrated that the small-bite suture technique significantly reduces the risk of IH [35]. This approach is implemented in our practice, although the suture length-to-wound length ratio is not routinely calculated. Consistent with findings in the literature, primary fascial repair using simple continuous suture at the time of initial IH has been identified as an independent risk factor for recurrence [22, 36]. More recently, *Frountas et al.* reported a 50% reduction in recurrence rates following laparoscopic repair in liver transplant recipients [37].

Immunosuppression is frequently identified as a risk factor for incisional hernia (IH) following organ transplantation [38, 39]. In the context of liver transplantation, mycophenolate mofetil (MMF) and sirolimus are the two primary agents associated with an increased risk of IH [9, 40]. However, our study did not confirm a significant association between these immunosuppressive agents and hernia recurrence. The use of low-dose corticosteroids, their early discontinuation, and the individualized adjustment of MMF based on area under the curve (AUC) monitoring may account for the absence of a statistically significant correlation in our cohort.

According to *Smith et al.*, overweight status (defined as a
BMI > 25 kg/m²) is an independent risk factor for incisional
hernia (IH), likely due to the increased intra-abdominal
pressure it exerts, resulting in greater mechanical stress on
the abdominal wall [34]. Our findings are consistent with

the literature, as BMI was also associated with a height-
ened risk of recurrence. However, BMI remains a limited
and imprecise indicator of body composition and fat mass
distribution [4]. For this reason, it was excluded from our
multivariate analysis in favor of more accurate assessments
of parietal and visceral adiposity.

Visceral obesity is a well-established risk factor for com-
plications in abdominal surgery [41], yet it remains under-
recognized in the context of liver transplantation. Visceral
fat area (VFA) is a valuable parameter for assessing this risk;
however, standardization of the computed tomography (CT)
slice level is essential to ensure reliable comparisons across
studies [42, 43]. In the present study, VFA was measured at
the level of the third lumbar vertebra (L3), consistent with
standard practices for the assessment of sarcopenia. It is
worth noting that in this study, visceral obesity appeared to
be a potential risk factor for incisional hernia, as the asso-
ciation did not reach the conventional threshold for statis-
tical significance in the Fine and Gray model (P=0.055).
This attenuation may be attributed to the limited number of
events and the incorporation of the competing risk of death,
which reduces the statistical power of the analysis. Although
the association did not reach statistical significance, the con-
sistency of the effect size and the direction of the associa-
tion may suggest a potential clinical relevance of visceral
obesity as a risk factor for incisional hernia recurrence. This
warrants further investigation in larger cohorts.

Standardization of Hounsfield unit (HU) thresholds for the assessment of visceral fat is also essential. In this study, we applied a range of –190 to –30 HU, although other investigations have used narrower intervals, such as –150 to –50 HU [44]. Likewise, the definition of visceral obesity remains a topic of ongoing debate. We adopted a threshold of 100 cm²/m², as recommended by the Japan Society for the Study of Obesity [45]. However, the notable morphological differences between Asian and European populations suggest that this threshold may require adjustment to allow for meaningful comparisons across studies.

This study has several limitations. As a retrospective
analysis, it is subject to the methodological biases inher-
ent in this study design. Despite rigorous follow-up, the
diagnosis of incisional hernia (IH) may have been either
overestimated or underestimated, particularly in patients
with a lax abdominal wall or significant adipose pannicu-
lus—features commonly associated with metabolic syn-
drome. Moreover, in the absence of clinical complications,
computed tomography (CT) scans were not systematically
performed, potentially resulting in the underdiagnosis of
small or asymptomatic hernias. However, such cases were
not clinically relevant and did not warrant intervention [46].
## Conclusion

This study is the first to investigate body composition as a potential risk factor for incisional hernia (IH) recurrence in liver transplant recipients. Although sarcopenia was initially hypothesized to contribute to recurrence, our analysis did not reveal a statistically significant association. This suggests that sarcopenia may not be a major determinant of recurrence risk in this population. In contrast, our findings highlight the potential impact of visceral obesity, which was more consistently associated with recurrence. Given the increasing prevalence of overweight and obesity, targeted pre-transplant interventions addressing visceral adiposity may help reduce the long-term risk of IH recurrence.

**Supplementary Information** The online version contains supplementary material available at https://doi.org/10.1007/s10029-025-03400-0.

**Funding** Open access funding provided by Centre Hospitalier Universitaire de Rennes.

## Declarations

**Ethical approval** Approval from the University Hospital of Rennes Ethics Committee has been obtained (N°25.21).

**Consent to participate** No patient objected to taking part in this study.

**Conflict of interest** The authors have no conflict of interest to disclose.

**Open Access** This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

## References

1. Bosanquet DC et al (2015) Systematic review and Meta-Regression of factors affecting midline incisional hernia rates: analysis of 14 618 patients. PLoS ONE 10(9):e0138745. https://doi.org/10.1371/journal.pone.0138745

2. de Goede B et al (2014) Incisional hernia after liver transplantation: risk factors and health-related quality of life. Clin Transpl 28(7):829-836. https://doi.org/10.1111/ctr.12386

3. Heimann TM et al (2018) Incidence and factors correlating with incisional hernia following open bowel resection in patients with inflammatory bowel disease: A review of 1000 patients. Ann Surg 267(3):532-536. https://doi.org/10.1097/SLA.00000000000002120

4. Hede P et al (2015) Influence of BMI on short-term surgical outcome after colorectal cancer surgery: a study based on the Swedish National quality registry. Int J Colorectal Dis 30(9):1201-1207. https://doi.org/10.1007/s00384-015-2280-0

5. Sørensen LT et al (2005) Smoking is a risk factor for incisional hernia. Arch Surg 140(2):119-123. https://doi.org/10.1001/archsurg.140.2.119

6. Fikatas P et al (2013) Incidence, risk factors and management of incisional hernia in a high volume liver transplant center. Ann Transpl 16:18:223-230. https://doi.org/10.12659/AOT.883914

7. D'Angelica M et al (2006) Optimal abdominal incision for partial hepatectomy: increased late complications with Mercedes-type incisions compared to extended right subcostal incisions. World J Surg 30(3):410-418. https://doi.org/10.1007/s00268-005-0183-x

8. Piardi T et al (2010) Incisional hernia repair after liver transplantation: role of the mesh. Transpl Proc 42(4):1244-1247. https://doi.org/10.1016/j.transproceed.2010.03.085

9. Kahn J et al (2007) Incisional hernia following liver transplantation: incidence and predisposing factors. Clin Transpl 21(3):423-426. https://doi.org/10.1111/j.1399-0012.2007.00666.x

10. Buchard B et al (2020) A. Assessment of malnutrition, sarcopenia and frailty in patients with cirrhosis: which tools should we use in clinical. Practice? Nutrients 12(1):186. https://doi.org/10.3390/nu12010186

11. Cruz-Jentoft AJ et al (2019) Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing 48(1):16-31. http://doi.org/10.1093/ageing/afy169

12. Lang T et al (2010) Sarcopenia: etiology, clinical consequences, intervention, and assessment. Osteoporos Int 21(4):543-559. http://doi.org/10.1007/s00198-009-1059-y

13. Tandon P et al (2012) Severe muscle depletion in patients on the liver transplant wait list: its prevalence and independent prognostic value: impact of severe muscle depletion on Wait-List mortality. Liver Transpl 18(10):1209-1216. https://doi.org/10.1002/lt.23495

14. Terjimanian MN et al (2016) Abdominal adiposity, body composition and survival after liver transplantation. Clin Transpl 30(3):289-294. https://doi.org/10.1111/ctr.12688

15. Mourtzakis M et al (2008) A practical and precise approach to quantification of body composition in cancer patients using computed tomography images acquired during routine care. Appl Physiol Nutr Metab 33(5):997-1006. https://doi.org/10.1139/H08-075

16. Clavien PA et al (2009) The Clavien-Dindo classification of surgical complications: Five-Year experience. Ann Surg 250(2):187-196. https://doi.org/10.1097/SLA.0b013e3181b13ca2

17. Mitsiopoulos N et al (1998) Cadaver validation of skeletal muscle measurement by magnetic resonance imaging and computerized tomography. J Appl Physiol 85(1):115-122. https://doi.org/10.1152/jappl.1998.85.1.115

18. Montano-Loza AJ et al (2014) Severe muscle depletion predicts postoperative length of stay but is not associated with survival after liver transplantation: sarcopenia after liver transplantation. Liver Transpl 20(6):640-648. https://doi.org/10.1002/lt.23863

19. Nishigori T et al (2016) Impact of sarcopenic obesity on surgical site infection after laparoscopic total gastrectomy. Ann Surg Oncol 23(4):524-531. https://doi.org/10.1245/s10434-016-5385-y

20. Wasielewski E, Medrxiv et al (2024) https://doi.org/10.1101/2024.03.11.24304074

21. Garmpis N et al (2019) Incisional hernias post liver transplantation: current evidence of epidemiology, risk factors and laparoscopic Versus open repair. A review of the literature. Vivo 33(4):1059-1066. https://doi.org/10.21873/invivo.11574
22. Cos H et al (2020) Incisional hernia after liver transplantation: risk factors, management strategies and long-term outcomes of a cohort study. Int J Surg 78:149-153. https://doi.org/10.1016/j.ijsu.2020.04.048

23. Ferri JVV, EARLY INCISIONAL HERNIA AFTER LIVER TRANSPLANTATION: RISK FACTORS AND HERNIA REPAIR RESULTS (2022) ABCD Arq Bras Cir Dig São Paulo 4:35e1698. https://doi.org/10.1590/0102-672020220002e1698

24. Perrakis A et al (2021) Incisional hernia after liver transplantation: mesh-based repair and what else? Surg Today 51(5):733-737. https://doi.org/10.1007/s00595-020-02162-9

25. Tastaldi L et al (2019) Posterior component separation with transversus abdominis release (TAR) for repair of complex incisional hernias after orthotopic liver transplantation. Hernia 23(2):363-373. https://doi.org/10.1007/s10029-019-01918-8

26. Weiss S et al (2015) Outcome analysis of laparoscopic incisional hernia repair and risk factors for hernia recurrence in liver transplant patients. Clin Transpl 29(10):866-871. https://doi.org/10.111/ctr.12558

27. Martin L et al (2013) Cancer cachexia in the age of obesity: skeletal muscle depletion is a powerful prognostic factor, independent of body mass index. J Clin Oncol 31(12):1539-1547. https://doi.o rg/10.1200/JCO.2012.45.2722

28. Huguet A et al (2018) The Psoas muscle transversal diameter predicts mortality in patients with cirrhosis on a waiting list for liver transplantation: A retrospective cohort study. Nutrition 51-52:73-79. https://doi.org/10.1016/j.nut.2018.01.008

29. Carey EJ (2014) Sarcopenia in solid organ transplantation. Nutr Clin Pract 29(2):159-170. https://doi.org/10.1177/088453361352 0619

30. van Vugt JLA et al (2016) Systematic review and Meta-Analysis of the impact of computed Tomography-Assessed skeletal muscle mass on outcome in patients awaiting or undergoing liver transplantation. Am J Transpl 16(8):2277-2292. https://doi.org/10.111 1/ajt.13732

31. Alnassar S et al (2012) Incisional hernia postrepair of abdominal aortic occlusive and aneurysmal disease: five-year incidence. Vascular 20(5):273-277. https://doi.org/10.1258/vasc.2011.oa03 32

32. Gianchandani R et al (2020) Laparoscopic incisional hernia repair after liver transplantation: Long-Term series and literature review. Transpl Proc 52(5):1514-1517. https://doi.org/10.1016/j. transproceed.2020.01.082

33. Butler JR et al (2021) Incisional hernia after orthotopic liver transplantation: A systematic review and Meta-analysis. Transpl Proc 53(1):255-259. https://doi.org/10.1016/j.transproceed.2020. 03.019

34. Smith CT et al (2015) Incidence and risk factors of incisional hernia formation following abdominal organ transplantation. Surg Endosc 29(2):398-404. https://doi.org/10.1007/s00464-014-368 2-8

35. Deerenberg EB et al (2015) Small bites versus large bites for closure of abdominal midline incisions (STITCH): a double-blind, multicentre, randomised controlled trial. Lancet 386(10000):1254-1260. https://doi.org/10.1016/S0140-6736(15) 60459-7

36. Müller V et al (2003) Incisional hernia repair after orthotopic liver transplantation: a technique employing an inlay/onlay polypropylene mesh. Langenbecks Arch Surg 388:167-173. https://doi.org/10.1007/s00423-003-0384-4

37. Frountzas M et al (2020) Open or laparoscopic mesh repair of incisional hernia in patients that underwent liver transplantation: A systematic review and proportional meta-analysis. Clin Transpl 34(12):e14103. https://doi.org/10.1111/ctr.14103

38. Gómez R et al (2001) Incidence and predisposing factors for incisional hernia in patients with liver transplantation. Hernia 5(4):172-176. https://doi.org/10.1007/s10029-001-0032-2

39. Janßen H et al (2002) Causative factors, surgical treatment and outcome of incisional hernia after liver transplantation. Br J Surg 89(8):1049-1054. https://doi.org/10.1046/j.1365-2168.2002.021 65.x

40. Montalti R et al (2012) Early use of mammalian target of Rapamycin inhibitors is an independent risk factor for incisional hernia development after liver transplantation: M TOR inhibitors as risk factors for IH S after LT. Liver Transpl 18(2):188-194. https://doi.org/10.1002/lt.22445

41. Watanabe J et al (2014) The impact of visceral obesity on surgical outcomes of laparoscopic surgery for colon cancer. Int J Colorectal Dis 29(3):343-351. https://doi.org/10.1007/s00384-013-1803 -9

42. Kang J et al (2012) Impact of fat obesity on laparoscopic total mesorectal excision: more reliable indicator than body mass index. Int J Colorectal Dis 27(4):497-505. https://doi.org/10.10 7/s00384-011-1333-2

43. Ishii Y et al (2005) Impact of visceral obesity on surgical outcome after laparoscopic surgery for rectal cancer. Br J Surg 92(10):1261-1262. https://doi.org/10.1002/bjs.5069

44. Ishizu Y et al (2021) Impact of visceral fat accumulation on the prognosis of patients with cirrhosis. Clin Nutr ESPEN 42:354-360. https://doi.org/10.1016/j.clnesp.2021.01.008

45. Examination Committee of Criteria for (2002) Japan society for the study of obesity new criteria for ‘obesity disease’ in Japan. Circ J 66(11):987-992. https://doi.org/10.1253/circj.66.987

46. Liang MK et al (2017) Ventral hernia management: expert consensus guided by systematic review. Ann Surg 265(1):80-89. https://doi.org/10.1097/SLA.0000000000001701

**Publisher's note** Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.