Incisional hernia (IH) is one of the most common complications of abdominal surgery, with an incidence ranging from 5 to 20%, and even up to 35% in high-risk patients with diabetes mellitus. Large incisional hernia (LIH) is an important type of IH, but there is no consensus on the definition of LIH at home and abroad. With reference to the European Hernia Society and the criteria for complex abdominal wall hernia, and considering the guiding significance for the selection of surgical procedure, the criteria for LIH are mostly IH width ≥ 250px or hernia to abdominal volume ratio ≥ 15-20%. With advances in medical technology, the chances of patients recovering from various mega-invasive surgeries have greatly increased, which has led to a corresponding increase in the rate of postoperative LIH, with studies showing that LIH accounts for 15-47% of all IH, and LIH with a width ≥375 px accounts for 11% of IH. Unlike small to medium-sized IH in general, LIH significantly affects the function of the patient’s abdominal wall, with high surgical risks and a high rate of postoperative recurrence, and there is a lack of high evidence level clinical studies regarding its treatment to date. Therefore, the optimal surgical treatment of patients with LIH is a major challenge that abdominal wall surgeons must face. The use of implantable materials is aimed at strengthening or replacing the defective abdominal wall and can reduce postoperative recurrence of IH by more than 50% compared to direct suture repair. These include reinforcement, which closes the abdominal wall defect, and bridging, which leaves the defect open and fixes the implant directly to the edge of the defect. Reinforcement or bridging of abdominal wall defects can be performed by placing the implant material in front of the myofascia (Onlay), behind the myofascia (Sublay) and within the abdominal cavity (intraperitoneal onlay mesh, IPOM/Underlay), or by placing the implant material between the muscles (Inlay). The advantage of strengthening repair is that the closure of the defect allows the abdominal wall to be re-encapsulated by myofascial tissue with blood supply and innervation, and the close contact of the well vascularized tissue with the implant material facilitates tissue ingrowth and functional abdominal wall repair, whereas bridging repair only restores the anatomical continuity of the abdominal wall and does not achieve functional abdominal wall repair. Deerenberg et al. published a systematic review study of 3945 patients with LIH in 2015, which is the largest sample size study on LIH to date.Deerenberg et al. found that the implementation of non The postoperative recurrence rate for LIH treated with non-implantable tissue repair including component separation technique (CST) alone was about 12-44%; the postoperative recurrence rate for LIH treated with implantable reinforced repair after closure of the abdominal wall defect in various ways was about 3.6-11%; and the postoperative recurrence rate for LIH repaired with open or lumpectomy IPOM bridging was 8.3% and 5.6%, respectively. The recurrence rates of Sublay and IPOM-reinforced repair were 3.6% and 3.2%, respectively, which were significantly lower than those of other repair modalities. Further analysis using a generalized linear model showed that the annual risk of recurrence for open non-material placement repair of LIH was 4.6-8.7%, while the annual risk of recurrence for open material placement reinforced repair of LIH was 0.3-3.4%, with only 0.5% for sublay and Underlay/IPOM reinforced repair. The results of this study clearly indicate that implant-reinforced repair has significant advantages over direct tissue repair and bridging repair in reducing the recurrence rate of LIH, and the use of Sublay-reinforced repair for LIH is recommended by several clinical studies. The recurrence rate of Inlay bridging repair is more than 40%, so bridging repair should be avoided as much as possible. The core of abdominal wall repair is the closure of the abdominal wall defect, which not only can significantly reduce the occurrence of various complications, including recurrence, but more importantly, only the closure of the abdominal wall defect can achieve the real sense of abdominal wall functional reconstruction. In 1990, Ramirez in the United States first reported the component separation technique (CST) on the basis of animal experiments. technique (CST) was first reported by Ramirez in the United States in 1990 on the basis of animal experiments, which was performed by extensive separation of skin and subcutaneous tissues and release of the lateral abdominal wall tendinous tissue to achieve defect closure. Bilateral CST can release up to 500px of the abdominal wall at the umbilical level, which allows for closure of most LIH defects. However, the recurrence rate after CST alone for abdominal wall defect repair can be as high as 30-55% and the complication rate can be as high as 60-70%, therefore, various modified CST and endoscopic component separation techniques (ECST) based on implant-reinforced CST repair with preservation of the peritoneal wall penetrating vessels have been extensively tried. The recurrence rate of hernia after CST/ECST-enhanced repair is reduced to approximately 10-20%, the incisional complication rate of ECST (10-20%) is significantly lower than that of CST (30-60%), and the incisional infection rate (6%) is significantly lower than that of open CST (28%). Currently, CST + Sublay or Underlay reinforced repair has become the mainstay of LIH treatment, and ECST + IPOM reinforced repair is being tried by an increasing number of physicians. However, CST/ECST has its own shortcomings. Although existing studies have shown that 95-98% of LIH can be closed by CST/ECST, CST/ECST is not suitable for those with LIH defects >500 px or those with severe lesions in the lateral abdominal wall. III. Surgical approaches and options for LIH The current surgical approaches for LIH include: (1) open non-implantable (1) open non-implantable material repair: including open CST, modified CST with subcutaneous tunnels to preserve the perforating vessels, and tenoplasty with reversed sutures of the rectus abdominis sheath; (2) open implantable material repair: including reinforced and bridging repair of LIH with implantable material in Onlay, Sublay or Underlay. The closure of the LIH defect in the reinforced repair often requires the assistance of CST to achieve. In addition, the sandwich repair technique of preserving part of the hernia sac and using the anterior and posterior rectus abdominis sheaths to place nonabsorbable implantable materials has attracted more and more attention due to its relatively simple implementation and good results, with a postoperative recurrence rate of 0.8% and an annual recurrence risk of 0.3%; (3) lumpectomy implantable material repair: the lumpectomy technique for LIH is developing rapidly, and IPOM or bridging repair of LIH can also be performed lumpectively. The enhanced or bridging repair of LIH can also be performed lumpectopically, whereas to perform a full lumpectoscopic enhanced repair of LIH often requires the cooperation of ECST to complete. Compared with open surgery, the postoperative recurrence rate of lumpectomy is not significantly different from that of open surgery, but the incidence of complications, especially infection, is 2-3 times lower in lumpectomy than in open repair; (4) hybridization repair: for procedures that cannot be completed under lumpectomy alone, lumpectomy and open surgery can be performed together, which is common in cases such as severe intra-abdominal adhesions, where the release of intestinal adhesions and closure of defects are completed under open conditions. (5) Other procedures: the repair of LIH can also be accomplished with the application of autologous tissue grafts including tensor faciae latae (TFL), tissue expanders to expand the fascial tissues of the abdominal wall, botulinum toxin (BTX) injection, chemical CST, and laparoscopic surgery if the appropriate technical conditions are available. ) injection of chemical CST, and volume reduction techniques for intra-abdominal organ resection for LIH, but these procedures often require special techniques, some of which are limited in their application at the cost of damaging normal organ tissues. The following issues should be considered in the selection of the LIH procedure: (1) size of the defect: the majority of LIH can be repaired by CST/ECST after achieving defect closure, but how to deal with LIH defects >500 px?Malik et al. tried to preserve part of the hernia sac as an extension of the anterior and posterior rectus abdominis sheaths, transferring the peritoneum and anterior rectus abdominis sheath on one side to the contralateral rectus abdominis The sandwich method of preserving part of the hernia sac as an extension of the anterior and posterior sheaths of the rectus abdominis muscle, transferring the peritoneum and anterior sheath of the rectus abdominis muscle on one side to the posterior sheath of the rectus abdominis muscle on the opposite side, and interposing a nonabsorbable patch in the middle was a good treatment for LIH. However, the results need to be further confirmed because the implementation experience is still small. Various autologous tissue grafting techniques based on implanted materials for enhanced repair of LIH defects are another option, but they have shortcomings such as complicated surgical techniques and new injuries caused by the donor area. In addition, although the recurrence rate of bridging repair is significantly higher than that of strengthening repair, Sublay or Underlay/IPOM bridging repair is still an important option in cases where the defect really cannot be closed. (2) Choice of implant materials: The implant materials commonly used in clinical practice include various non-absorbable synthetic patches and biological patches. Synthetic non-absorbable patches can provide sufficient mechanical support for the abdominal wall, but their use as foreign bodies can easily lead to various complications. When Underlay/IPOM repair is performed, various anti-adhesive patches must be used to avoid intestinal adhesions, patch erosion, and even postoperative intestinal fistula as much as possible because the patches need to be in contact with the intra-abdominal organs. In the case of Sublay and Onlay repairs, large mesh lightweight polypropylene patches are used to reduce the possibility of postoperative complications. The use of expanded PTFE (ePTFE) should be used with caution. In an RCT of CST by de Vries Reilingh et al, the trial was terminated due to a 72.2% ePTFE infection rate and a 38.8% patch removal rate. Biological patches can have recurrence or bulge rates as high as 80-90% after IH bridging repair; therefore, biomaterials should not be used for bridging repair, but only for reinforced repair. (3) Soft tissue of the abdominal wall: whether the abdominal wall is contaminated or infected has an important impact on the choice of implant material and the prognosis of LIH. Biomaterials can provide a three-dimensional scaffold for regeneration and repair of the abdominal wall with support for neovascularization and host cell ingrowth to achieve tissue remodeling and repair, and thus have special value in cases of LIH with contamination or infection. The US ventral hernia working group (VHWG), based on a risk assessment of surgical site occurrence (SSO), suggests the potential advantage of biomaterial repair for patients with contaminated abdominal wall, suspected contamination, and previous incisional infection. For patients with significant infection, biomaterials are recommended for enhanced repair. (4) Surgeon’s experience: Deerenberg et al. found that the recurrence rate after reinforced repair of LIH was less than 3.6%, while the recurrence rate after reinforced repair of small and medium incisional hernias in general was 9-14%, which they attributed to the fact that LIH surgery is relatively complex and is performed by surgeons with extensive experience, so that the quality of surgery is guaranteed. A large body of literature has also confirmed that the personal experience of the surgeon is one of the most important factors in the prognosis of LIH, so LIH should be performed by a highly experienced senior specialist in hernia and abdominal wall surgery. Accurate preoperative evaluation of LIH is a prerequisite for surgical treatment, and imaging techniques, including CT, can provide accurate measurements of the defect, hernia sac, and abdominal cavity volume. Age, obesity, incisional contamination and infection, smoking, diabetes, chronic obstructive pulmonary disease (chroicotructiveulmoarydieae, COPD), history of abdominal aortic aneurysm surgery, and hormone use are all risk factors for recurrence after LIH, and preoperative measures such as weight loss, smoking cessation, prophylactic antithrombotic therapy, and bowel preparation should be given according to the patient’s condition. The preoperative progressive pneumoperitoneum (PPP) is a preoperative preparation for patients with large abdominal wall defects with abdominal wall insufficiency (LOD), but the cumbersome and invasive nature of the PPP approach limits its use, and the advent of CST/ECST The emergence of CST/ECST has made possible the release of the abdominal wall and the expansion of the abdominal cavity volume, solving the problem of difficult retrieval of the abdominal contents in the majority of LOD, and therefore PPP can be considered only in patients with LOD in whom CST/ECST cannot be performed. Common incisional complications after LIH include infection, hematoma, seroma, skin necrosis, and in patients with Underlay/IPOM repair, intestinal adhesions, intestinal obstruction, intestinal injury, patch erosion, intestinal fistula, chronic sinus formation, and other complications can also occur. Pulmonary complications are a particular concern after LIH surgery, mainly including pulmonary hypoventilation and pulmonary inflammation, which are related to the fact that the retracted abdominal contents can elevate the diaphragm after LIH defect closure, leading to difficulty in ventilation and air exchange. Therefore, during the closure of the defect, special attention should be paid to monitoring the airway pressure, as increased pressure often indicates the risk of ACS. And once this occurs it often requires reoperation or prolonged ventilator maintenance, sometimes for up to 2 weeks for the respiratory muscles. the overall mortality rate for LIH surgery is between approximately 0-5%, with the main causes associated with multi-organ failure, intestinal necrosis, intestinal obstruction, patch infections, sepsis, etc. However, the actual mortality rate of LIH without high-risk factors such as infection is only 0.4%, and its occurrence is mostly unrelated to the surgical technique itself, but mainly due to cardiovascular disorders. In conclusion, LIH should be treated as a special type of IH, and there is still no ideal procedure for its treatment. More large sample and multicenter RCT studies will provide important help and guidance for individualized selection of LIH surgery.