Factors that May Influence Failure of the Correction of the Musculoaponeurotic Deformities of the Abdomen

Sir: We would like to congratulate Dr. Brauman for his excellent study published recently entitled “Diastasis Recti: Clinical Anatomy” (Plast Reconstr Surg. 2008;122:1564–1569). The authors called our attention to the clinical aspect of the abdomen related to the width of diastasis, and they discovered that the relationship between these parameters is not always coincident. Most importantly, they verified that the correction of diastasis does not reflect a good cosmetic result in all cases, even if there is no recurrence of the diastasis with time. We completely agree with that, and we would like to add two points. The first point is that not all deformities can be corrected surgically. The surgical correction will not be effective in cases in which the intraabdominal pressure is very high because of fat accumulation. In these cases, although diastasis may not recur, there will be an expansion of the musculoaponeurotic layer that will become lax with time. Patients who present a weak musculoaponeurotic layer will also present projection of the abdominal contour. These patients may present an altered composition of the collagen fibers. There are two types of collagen fibers: type I and type III. Type I fibers present a higher tensile strength as compared with the type III fibers.1 Patients who present direct groin hernias present a higher number of type III fibers. Also, there is evidence that elderly patients present a higher number of type III fibers as compared with type I fibers.2 Therefore, patients present a more lax aponeurosis with age. For this reason, abdominal circumference increases and, even with surgical correction, these patients may have a poor cosmetic result. Although it may seem that plastic surgeons have limited action over the aponeurosis, it is possible to work in other areas of the musculoaponeurotic layer. We have created a classification in which four different corrections can be used to correct these deformities.3 The external oblique aponeurosis can be plicated, and this muscle can be advanced in specific deformities. The second point is that not all patients present rectus diastasis secondary to pregnancy. Some patients (approximately 7 percent of our cases) may have a lateral insertion of the recti muscles on the costal margins: type C of our classification.3 These patients may present hernias at the supraumbilical area and at the umbilicus. They are diagnosed by general surgeons as patients with epigastric hernias. We think that the use of “congenital rectus diastasis” is a more correct name, as not all patients present hernias. These patients may have recurrence of the rectus diastasis in the upper abdomen if the correction is made only by the plication of the anterior rectus sheath because there will occur a “violin string effect.” As the recti muscles are apart from each other in their insertion, with the repeated contraction of these muscles, a dehiscence of the plication may occur.4 If that occurs, a bulge will be formed at the superior abdomen, and the only way to correct it is to perform the entire operation again and advance the recti muscles. Therefore, the plication of the anterior recti sheaths, as Dr. Brauman suggests in his article, is not the absolute way to correct abdominal wall deformities. There are other techniques that can be helpful, depending on the deformity. Also, it is important to mention that, in some cases, it is not possible to surgically correct certain deformities of the musculoaponeurotic layer. Fabio Xerfan Nahas, M.D., Ph.D. Marcus Vinicius J. Barbosa, Ph.D. Lydia M. Ferreira, M.D., Ph.D. Department of Surgery Division of Plastic Surgery Federal University of São Paulo São Paulo, Brazil