|Year : 2019 | Volume
| Issue : 2 | Page : 33-38
The breakthrough on evaluation and treatment in incisional hernia with loss of domain
Dailei Qin, Shibo Wei, Jiyu Tian, Zhiwei Guo, Xian Li, Yuhao Yan, Hangyu Li
Department of Hernia and Abdominal Wall Surgery, The Fourth Hospital of China Medical University, Shenyang 10032, China
|Date of Submission||12-Jan-2019|
|Date of Acceptance||18-Feb-2019|
|Date of Web Publication||10-May-2019|
Dr. Hangyu Li
Department of Hernia and Abdominal Wall Surgery, The Fourth Hospital of China Medical University, Shenyang 10032
Source of Support: None, Conflict of Interest: None
Part of the patients with incisional hernia (IH) suffered from constipation or even circulatory impairment, which is called large IH with loss of domain (LOD) or giant IH. For now, there is still controversy about the definition and pathomechanism of the LOD; meanwhile, there is no clear criterion for evaluating and treating patients with LOD. A systematic search of the literature was implemented in PubMed and the Cochrane database by using the keywords “IH, abdominal wall function(AWF), LOD” and got 60 publications finally. First, there is still no unified definition for LOD, but we found that it was translated into a situation that abdominal content can hardly be reduced with AWF deficiency in 2018th Chinese Guidelines. Second, we concluded that poor abdominal wall contraction caused by muscular atrophy or fibrillation after large area aponeurosis released shall be important pathomechanism of LOD. Third, we found that there are different methods for evaluating LOD, while the activity evaluation may be most useful. Finally, component separation technique (CST), bridge repair or utotransplantation have been recommended in many publications for variable condition. The definition of LOD is better to be divided into the functional deficiency and the anatomical defect just like Chinese guidelines. The pathomechanism of LOD was actually based on anatomical destruction of abdominal wall contraction system. The activity evaluation may be the most convenient method mentioned in the publications. CST was strongly recommended to be used in giant hernia, the defect of which can be hardly closed. Patients who have IH with LOD are proposed to receive hernioplasty as early as possible because of the impendency to reconstruct the large defect on the abdominal wall as well as restoration of the AWF. Surgeons may select appropriate CST to repair IH according to the length of the defect.
Keywords: Abdominal wall function, bridge repair, component separation technique, incisional hernia, loss of domain
|How to cite this article:|
Qin D, Wei S, Tian J, Guo Z, Li X, Yan Y, Li H. The breakthrough on evaluation and treatment in incisional hernia with loss of domain. Int J Abdom Wall Hernia Surg 2019;2:33-8
| Introduction|| |
Abdominal wall bugle is an common situation for patients with incisional hernia (IH) while some of them may also suffer from defecation dysfunction and micturition disorder. Furthermore, they often complained about chronic low back pain in daily life, and it is believed that the abdominal wall function (AWF) deficiency has a primary responsibility., AWF assisted human body with movement, excretion, respiration, circulation, and anatomical stabilization, and it may fall into a decline with expansion of defect on abdominal wall (AW)., Patients may still be asymptomatic when the defect diameter is <10 cm;,, on the contrary, they will get extra functional impairment in respiration and circulation when the defect area is >10 cm and the volume ratio exceeded 20% between hernia sac and abdominal cavity., It is called large IH with loss of domain (LOD) or giant IH., The LOD reminds us that the abdominal wall reconstruction (AWR) should consist of anatomical as well as functional reconstruction. However, there is still no enough attention put on the AWF and LOD in many guidelines and prospective randomized controlled trials produced in China or the west.,,,,,, The present article introduces new progress in evaluation and treatment in patients with LOD according to the literature review.
| The Pathomechanism of Loss of Domain|| |
There is still controversy about the definition of LOD. It may be defined as “viscera lost their right of domain” or “loss of abdominal cavity volum” while it has been interpreted as a situation that hernia content can be hardly reduced into abdominal cavity, causing the AWF deficiency in 2018th Chinese Guidelines for the diagnosis and treatment of abdominal wall IH.,
Pathomechanism of loss of domain
Until now, there is no clear explanation for the pathomechanism of LOD, but fortunately, there are some manuscripts that can reveal it preliminarily. Den, Shestak, Kuo, Criss, and Jensen had focused on what can primary fascia closure bring to patients with LOD.,,,, It reflected the possibility that fascia closure especially Linea alba reconstruction make for the AWF restoration, moreover, it is also hypothesized that contraction system reload after reconstruction of insertion port formed by tendinous tissue played the key role.,, De Silva found hyperplasia in rectus abdominis, internal oblique, and external oblique, but hypotrophy in trasversus abdominis in patients received transversus abdominis release (TAR);,,, similarly, we can find external oblique hypotrophy in external oblique release. He hypothesized that aponeurosis released combined with muscle contractive dysfunction and it can be reactivated by aponeurosis reconstruction which is beneficial to AWF restoration. Second, the rest of AM would like to be hyperplasia gradually when aponeurosis has been released partially to make up the deficiency generated on AW. Last but not the least, Duba and Culbertson had proved that muscle cells are easy to get atrophy or even fibrillation if contraction insufficiency happened; interestingly, they also found that the process in hypotrophy or fibrillation can also be rectified by proper tension imposed.,,, Finally, we can conclude that poor AM contraction caused by muscular atrophy or fibrillation after large area aponeurosis released shall be important pathomechanism of LOD.
| Evaluation of Loss of Domain|| |
AWF score is an suitable index reflecting the degree of LOD; moreover, we can estimate the surgical efficacy according to the variation of perioperative AWF score.
Activity evaluation is to evaluate AWF by investigating body activity. There are trunk raising and double leg lowering tests which can be used in exploration. The total score from the two test is an index used in AWF efficacy comparing between different patients [Table 1] and [Table 2].
Other evaluation methods
Except for activate evaluation, we can also assess AWF by using the sensors to gain the actual muscle force or with the help of surface electromyography (EMG) to check the electrical peak and so on [Table 3].
| Treatment for Loss of Domain|| |
Functional repair holds an equal important position as anatomical repair when patient has LOD, because AWF may decreased as soon as the separation happened in any part of muscular fasciae.,,, Meanwhile, AWF can be kept in nearly normal level from Linea alba reconstruction, although part of muscular fasciae has been left in situ.,, Hence, for middle giant IH, lateral muscular fasciae can be reconstructed partially in order to guarantee the integrity of Linea alba if there are challenges to close the abdominal cavity completely. As for lateral giant IH, the three pairs of abdominal muscle need to be reconstructed uniquely to ensure their own functions would not be frustrated; as we all know, oblique muscle has the function of rotating the trunk and flexing the spine laterally, transverses abdominis keep abdominal component in their right place, moreover, rectus abdominis has the function of flexing the trunk.
When the defect can be closed
Component separation technique
Component separation technique (CST) shall be a suitable method to treat the IH, especially when the defect is >10 cm. Surgeons can even repair incisional hernia with 20 cm length of defect at umbilical level, meeting the requirement for most of the patients going to receive AWR., CST can be divided into anterior CST (ACST) and posterior CST (PCST). ACST often been performed in the sapce between external and internal oblique. E-CST is a common type of ACST, separating the aponeurosis of external oblique easily without large free flap creation, which strongly reduce the infection possibility. E-CST shall be a technique fit for normal patient with IH and the patients under the risk of AW contamination such as AW fistula.,,, Surgeons can close the defect near 17cm length with E-CST. PCST usually been performed in the space between transverses abdominis and fascia transversalis. TAR belong to PCST, by which the mesh can be reinforced under the compression from muscle and abdominal cavity, reducing the risk of recurrence conspicuously. PCST has been honored as an technique as powerful as classic CST and it provided almost 24 cm in defect closing which is a bit wider than the classic one.,, Finally, we can engage TAR combined with E-CST when it is unable to close the abdominal cavity under physiological tension by using TAR alone.
Nowadays, the laparoscopic incisional hernioplasty is a new trend in IH treatment apart from the traditional ACST or PCST. Reinpold carried out the first mini/less open sublay (MILOS) surgery in Germany 2015, which put mesh sublay under unique laparoscopic equipment with minimal incision, while Köckerling engaged ELAR (endoscopic-assisted Linea alba reconstruction) in 2016 by putting mesh onlay through minimal incision, in which he cut off the anterior sheath of rectus abdominis with longitudinal incision of 2 cm lateral from middle line and then sutured mesh with prototheca laterally for reinforcement., Belyansky performed TAR under laparoscopy in 2015 which has been called L-TAR and he tried to complete it with robotic equipment in 2016., Costa repaired middle-line IH with mesh sublay under laparoscopy in 2016, which named Brazilian technology by Montgomery and it has been also praised as an innovation from traditional Rives-Stoppa., Schwarz demonstrated endoscopy-MILOS by using conventional laparoscopic equipment in umbilical hernia combined with rectus abdominis separation with mesh sublay and it generated the definition of reverse-TEP (R-TEP) at the same time. Recently, Binggen Li presents a new technique to repair middle-line IH under laparoscopy, which is called totally endoscopic sublay and he suggested the technique can treat IH in safety and efficiency with less invasion compared to Rives-Stoppa. For now, surgeons are more likely to repair the IH in preperitoneal space rather than the intra-abdominal cavity because of the delayed in the mesh technique progression when compared to the incisional hernioplasty development., Less complication formed by minimal invasion of laparoscopic technique would like to be the biggest advantage of L-CST, but the longer operation period and smaller defect restriction may be a huge hinder for L-CST prevalence, which require further evolution.,,,,
Trans-cutaneous closure of central defect
Trans-cutaneous closure of central defect is a technique to be used in IH repairment with defect <3 cm by pulling the defect close after puncture the epidermis on the both side of it. It is recommended to be performed in patients with parimary and small IH.
When the defect is unable to be closed
Except for higher risk of recurrence, the abdominal compartment syndrome will be the worst result if intra-abdominal pressure exceed 20 mmHg after IH repairmen, especially when the defect is too large to be closed under physiological tension and it may even lead to death finally.,,,, We can figure out the ratio between hernia sac and abdominal cavity to estimate the risk of ACS preoperatively. The volum of hernia sac and abdominal cavity can be calculated by multiplying anteroposterior diameter by horizontal diameter got from computed tomography scan. Surgeons must choose the suitable method to close the abdominal cavity when the ratio exceeded 20%.
By suturing the mesh with margin of defect instead of closing it.,, The separation of muscular fasciae may still remain elite, and it was demonstrated that mesh can never replace the tenacious fascia, especially the Linea alba, and hence, it is hard for abdominal muscle to recover from the status in hypotrophy or fibrillation; thus, it carried higher risk of recurrence but no effect on AWF restoration.,,,,, The implementation rate of bridge repair is no >10% worldwide. It is worth to be mentioned that different grade of elasticity can be collected in different materials of mesh and it is also happened when the mesh been constrained in different direction. meanwhile, elasticity raised in longitudinal direction is stronger than transverse direction, so, we should chose an suitable mesh and suture it in an appropriate direction during the operation.,,,
There are pedicle flap and free flap used in autotransplantation alternatively. It is necessary for free flap transplanting using microvascular anastomosis, and hence, it is more likely to be engaged in professional IH medical center; last but not the least, AM may turn into contracting disorder and get hypotrophy gradually, thus leading to IH recurrence eventually. So, the autotransplantation is often performed with CST and mesh utilization at same time in order to avoid hernia recurrence.,,,
As for giant IH, the AWF deficiency is usually in direct proportion to the area defect, but the relationship between nongiant IH and AWF deficiency is still unclear. It is hypothesized by Jensen the AWF deficiency had already occurred even when the defect is small. However, there are no much patients who suffer from symptoms mentioned at first until their defect exceeds 10 cm, and compensation from healthy tissue around small defect is thought to be the contributor., As a matter of fact, AWF is in decline when small defect grows into a big one and leads to LOD finally. It is necessary for surgeons to make an appropriate surgical plan as early as possible to solve the problem in patients who suffered from giant IH or take precaution against LOD in patients with nongiant IH. Nonlaparoscopic IH repair techniques are recommended in most of the cases in consideration of shorter surgical time and wider defect area can be fixed when compared to laparoscopic repair, finally, the explicit recommendation sited in [Table 4].,
| Expectation|| |
There are still some issues about patients with LOD which need further clarified. At first, we shall classify giant IH into certain type by AWF recording and estimate the difficulty we may meet during the operation. Then, is there any difference between three groups of muscle on anterior AW in AWF creation or how can we rebuild Linea alba while causing minimal damage to AWF simultaneously. Finally, we shall watch out for recurrence when AWF stays in low level for a long time after surgery.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
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[Table 1], [Table 2], [Table 3], [Table 4]