Page 331 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

General discussion
An attempt has been made to reduce the incidence of incisional hernia (IH) through optimizing all techniques for closing abdominal wall incisions. The STITCH trial con rmed the positive results of the Swedish research group of Israelsson, that developed the ‘small bites’ suture technique(1). Although in our systematic review and meta-analysis, a superior suture material for suturing the abdominal fascia could not be detected, evidence from earlier systematic reviews and meta-analyses demonstrated a combination of a continuous suture technique with a non-absorbable or slowly-absorbable suture material to be superior to an interrupted suture technique with a fast-absorbable suture on the incidence of IH(2, 3). Furthermore, a continuous technique is, of course, faster than an interrupted technique(2).
Evaluating the evidence from the existing literature, the European Hernia Society formulated guidelines on the optimal method of closing abdominal wall incisions. It is advised to use a continuous suture technique with a slowly- absorbable suture, since using a non-absorbable suture is associated with increased incidence of prolonged wound pain and suture sinus formation(3). Furthermore, a ‘small bites’ technique with a suture to wound length radio of at least 4:1 is recommended, in part based on the results of the STITCH trial, providing level 1 clinical evidence.
When taking into account the biology of wound healing, using a slowly- or non-absorbable suture to suture the fascia seems most logical. Fascial healing starts with the recruiting of in ammatory cells. Two to ve days after laparotomy, broblasts enter the wound side and start producing collagen. During the proliferation phase of the rst three weeks, mainly type III collagen is produced and an extracellular matrix is created. Type III collagen consists of thin, weak bres, and is replaced by strong and thick type I collagen during the following maturation phase(4, 5). The last part of the maturation phase is the remodeling or realignment of collagen bres along tension lines – a process which can take years. The half-life tensile strength of absorbable sutures like polyglactin 910 (Vicryl®) and polyglycolid acid (Dexon®) is around 2-3 weeks(6), suggesting an insu cient support of the healing linea alba after this time. The half-life tensile strength of the slowly-absorbable suture polydioxanone (PDS®) is 6 weeks(6). Since healing fascia needs at least 14 days to regain its strength(4, 7), using a fast- absorbable suture will probably not provide support for long enough.
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General discussion and future perspectives
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