Long-term follow-up of full-thickness skin grafting in giant incisional hernia repair: a randomised controlled trial

Prevascularized Hydrogel Enhancing Innervation and Repair of Full-Thickness Volumetric Muscle Loss in Abdominal Wall Defects

Current materials for repairing abdominal peritoneal defects face rapid degradation, infection risk, insufficient vascular ingrowth, slow muscle regeneration, and suboptimal postoperative integration, often causing fibrotic healing and hindering volumetric muscle loss (VML) repair exceeding 30%. To address these issues, photo-cross-linkable gelatin hydrogels are combined with blood vessel-forming cells to reconstruct vascular networks, providing temporary nutrient and gas channels that support cell repair. By developing a polymer-chain propagation time technique, hydrogel properties are optimized, avoiding limitations of conventional light exposure. These gels guide blood-vessel formation in vitro and promote robust microvessel and neural development in vivo. Precise control of light exposure and propagation times balances cross-linking and degradation, fostering blood vessel growth and host motor neuron ingrowth. In 55% VML, these hydrogels enable full-thickness abdominal muscle regeneration, restoring up to 70% of lost muscle while mimicking healthy tissue's strength and structure. Achieving higher degradation rates and a vascular density exceeding 50 vessels/mm-2 is essential for functional muscle repair. These strategies effectively bridge current clinical gaps, advancing regenerative medicine. The ability to fine-tune degradation and stiffness underscores gelatin hydrogels' potential as cell carriers, allowing the reconstruction of temporary vascular and neural channels at injury sites and significantly enhancing muscle tissue regeneration.

Complex abdomen: a scoping review

PURPOSE

This scoping review aimed to systematically map the existing evidence on the surgical management of complex abdominal wall hernias (CA), focusing on patient-specific factors, hernia characteristics, contamination and operative strategies to their management, in order to identify research gaps and areas for clinical improvement.

METHODS

A comprehensive literature search was conducted in PubMed and Scopus, covering publications from January 2015 to June 2024. A total of 6,445 articles were identified, of which 357 met inclusion criteria (303 primary studies and 54 systematic reviews). Studies were classified into three categories: patient-related factors (P), hernia-specific features (H), and contamination (W).

RESULTS

Patient-related factors, particularly obesity and associated comorbidities, were consistently related to higher rates of morbidity and hernia recurrence despite prehabilitation and bariatric surgery were evaluated, results were inconclusive. Hernia-specific features, including large defect size and loss of domain, were associated with increased complication rates. Midline restoration and its achievement with component separation or preoperative botulinum toxin injections, were extensively studied, showing potential benefits. In contaminated settings, synthetic meshes outperformed biologic alternatives, demonstrating lower recurrence and morbidity rates in recent trials. Research in biosynthetic mesh is still needed.

CONCLUSION

Surgical management of CA remains a highly demanding clinical scenario with significant variability in outcomes influenced by patient factors and hernia characteristics. Techniques such as component separation and the use of synthetic meshes hold promise, but further high-quality, randomized trials are required to establish standardized protocols and optimize clinical outcomes in this challenging patient population.

A Scoping Review of Quality-of-Life Assessments Employed in Abdominal Wall Reconstruction

INTRODUCTION

Surgeons use several quality-of-life instruments to track outcomes following abdominal wall reconstruction (AWR); however, there is no universally agreed upon instrument. We review the instruments used in AWR and report their utilization trends within the literature.

METHODS

This scoping review was reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis extension for Scoping Reviews guidelines using the PubMed, Embase, Web of Science, ClinicalTrials.gov, and Cochrane databases. All published articles in the English language that employed a quality-of-life assessment for abdominal wall hernia repair were included. Studies which focused solely on aesthetic abdominoplasty, autologous breast reconstruction, rectus diastasis, pediatric patients, inguinal hernia, or femoral hernias were excluded.

RESULTS

Six hernia-specific tools and six generic health tools were identified. The Hernia-Related Quality-of-Life Survey and Carolinas Comfort Scale are the most common hernia-specific tools, while the Short-Form 36 (SF-36) is the most common generic health tool. Notably, the SF-36 is also the most widely used tool for AWR outcomes overall. Each tool captures a unique set of patient outcomes which ranges from abdominal wall functionality to mental health.

CONCLUSIONS

The outcomes of AWR have been widely studied with several different assessments proposed and used over the past few decades. These instruments allow for patient assessment of pain, quality of life, functional status, and mental health. Commonly used tools include the Hernia-Related Quality-of-Life Survey, Carolinas Comfort Scale, and SF-36. Due to the large heterogeneity of available instruments, future work may seek to determine or develop a standardized instrument for characterizing AWR outcomes.

Comparison of mechanical properties and host tissue response to OviTex™ and Strattice™ surgical meshes

PURPOSE

This study compared the in vitro/benchtop and in vivo mechanical properties and host biologic response to ovine rumen-derived/polymer mesh hybrid OviTex™ with porcine-derived acellular dermal matrix Strattice™ Firm.

METHODS

OviTex 2S Resorbable (OviTex 2S-R) and Strattice morphology were examined in vitro using histology and scanning electron microscopy; mechanical properties were assessed via tensile test; in vivo host biologic response and explant mechanics were evaluated in a rodent subcutaneous model. Separately, OviTex 1S Permanent (OviTex 1S-P) and Strattice were evaluated in a primate abdominal wall repair model.

RESULTS

OviTex 2S-R demonstrated layer separation, whereas Strattice retained its structural integrity and demonstrated higher maximum load than OviTex 2S-R out-of-package (124.8 ± 11.1 N/cm vs 37.9 ± 5.5 N/cm, p < 0.001), 24 h (55.7 ± 7.4 N/cm vs 5.6 ± 3.8 N/cm, p < 0.001), 48 h (45.3 ± 14.8 N/cm vs 2.8 ± 2.6 N/cm, p = 0.003), and 72 h (29.2 ± 10.5 N/cm vs 3.2 ± 3.1 N/cm, p = 0.006) following collagenase digestion. In rodents, inflammatory cell infiltration was observed between OviTex 2S-R layers, while Strattice induced a minimal inflammatory response. Strattice retained higher maximum load at 3 (46.3 ± 27.4 N/cm vs 9.5 ± 3.2 N/cm, p = 0.041) and 6 weeks (28.6 ± 14.1 N/cm vs 7.0 ± 3.0 N/cm, p = 0.029). In primates, OviTex 1S-P exhibited loss of composite mesh integrity whereas Strattice integrated into host tissue with minimal inflammation and retained higher maximum load at 1 month than OviTex 1S-P (66.8 ± 43.4 N/cm vs 9.6 ± 4.4 N/cm; p = 0.151).

CONCLUSIONS

Strattice retained greater mechanical strength as shown by lower susceptibility to collagenase degradation than OviTex 2S-R in vitro, as well as higher maximum load and improved host biologic response than OviTex 2S-R in rodents and OviTex 1S-P in primates.

Comparison of Surgical Treatment Results of Large Incisional Hernias

Introduction Incisional hernias are one of the most common complications after abdominal surgery. Surgical repairs of large incisional hernias have higher complications and recurrence rates compared to smaller incisional hernia repairs. For this reason, it is a more difficult and experience-requiring application for surgeons. In addition, there is no evidence-based consensus in the literature regarding the optimal surgical treatment of large incisional hernias. The aim of this study is to compare the results of the three most common surgical treatment methods used in a tertiary university hospital for the repair of large incisional hernias in terms of patients' characteristics, recurrence, and complication rates of the treatment methods. Methods Between 2014 and 2020, 366 patients with incisional hernias with facial defects larger than 10 cm in a tertiary medical faculty hospital located in eastern Turkey were analyzed. Patients were divided into three groups according to the surgical method used: open onlay prolene mesh (OPM) method, laparoscopic intraperitoneal sublay dual mesh (IPSDM) method, and open IPSDM method. Postoperative complications were divided into five groups as follows: wound complications, complications due to surgical procedures, medical complications, recurrences, and mortality. Treatment methods were compared according to the demographic characteristics of the patients and the postoperative complication rates. Results Of the patients, 141 were male and 225 were female, and the mean age was 58.0 ± 28 years. Of the patients, 81.9% were operated on with the open OPM, 10.9% with the laparoscopic IPSDM, and 7.1% with the open IPSDM. Wound complications occurred in 26.7% of patients, surgical complications in 3.2%, medical complications in 6.5%, recurrence in 9.2%, and mortality in 0.8% of patients. Total wound complications were significantly higher in the open OPM group (30%) (p = 0.009). Total surgery complications were significantly higher in the laparoscopic IPSDM group (15%) (p = 0.002). There was no significant difference between groups for medical complications (p = 0.540). Although no recurrence was observed in the open IPSDM group, no significant difference was observed between the groups (p = 0.099). There was no difference in mortality rates between the groups (p = 0.450). The overall complication rate was highest in the open OPM group (48.3%) and lowest in the open IPSDM group (27%) (p = 0.092). The operative time was found to be significantly shorter in open IPSDM (p < 0.001). The length of hospital stay was highest in the open OPM group and lowest in the open IPSDM group (p = 0.450). Conclusions Although hernia defect is greater in the open IPSDM compared to other methods, this method is more advantageous in terms of the complication rate associated with the surgical procedure, the overall complication rate, the duration of surgery, and the recurrence rate. Laparoscopic IPSDM is a more advantageous method in terms of the overall wound and medical complications.

Reconstruction of Large Full-Thickness Abdominal Wall Defects Using a Free Functional Latissimus Dorsi Muscle

Introduction

The large full-thickness abdominal wall defect has to be treated by considering anatomical and functional requirements. The abdominal wall must regain total physiological function, which means that the full thickness abdominal wall defect must be reconstructed anatomically, not only according to the anatomical requirements but also maintaining the functional dynamic voluntary movement. Defects in the abdominal wall alter respiratory mechanics and can impair the diaphragm function. Additionally, muscles of the anterolateral abdominal wall increase the stability of the lumbar region of the vertebral column by tensing the thoracolumbar fascia and by increasing intraabdominal pressure.

Materials and Methods

The timing and method of reconstruction must be chosen depending upon the etiology of the defect. Severe traumatic injuries, abdominal wall infections, necrotizing soft tissue loss, or sepsis needs to undergo staged reconstruction following adequate debridement to control the infectious process, establish the zone of injury, and for proper treatment of intraabdominal pathology, thereby achieving temporary primary closure using split-thickness skin grafting to the viscera. At the time of definitive reconstruction, deep skin graft dermabrasion give us a facial-like layer with adequate strength to stabilize the static abdominal wall. This dermal layer is supported by free functional (innervated) latissimus dorsi muscle (fLDM), giving full anatomical coverage and functional stability. After oncologic resections full-thickness abdominal wall reconstruction was performed immediately with a combination of fLDM flaps and meshes.

Results

A total of 14 patients underwent abdominal wall reconstruction using the fLDM flap. Staged reconstruction was applied in 8 cases. In the remaining six cases, two had no mesh support, three had synthetic mesh, and one had a fascial graft, which were covered with fLDM flap. There were no free flaps failure. One flap revision due to venous anastomosis thrombosis was performed. Donor site seromas occurred in 5 cases and were treated with punction and direct doxycycline injection. Electromyographic testing postoperatively confirmed reinnervation of transplanted LDM.

Conclusion

Using fLDM as a definitive solution, we are not only able to repair soft tissue defects, but also reconstruct voluntary contractility and dynamic natural functional abdominal wall. Transplanted LDM offers enough contractile capacity and strength to replace the function of the missing abdominal wall muscles.