RESUMEN
PURPOSE: The purpose of this study is to evaluate the tension at the aponeurotic edges after the undermining of the anterior rectus sheath associated with the classic components separation in cadavers. METHODS: Twenty fresh adult cadavers were placed supine and an incision in the anterior rectus sheath was done, thus exposing the posterior sheath. The two levels to be studied were marked 3 cm above and 2 cm below the umbilicus. An analogical dynamometer was used to measure the traction values, consecutively during four stages as follows: initial stage, no aponeurotic undermining; Stage 1, separation of the anterior rectus sheaths; Stage 2, after Stage 1 the external oblique aponeurosis were incised along the semilunaris and the external oblique muscles were undermined; Stage 3, after Stage 2 rectus muscles were completely separated from their posterior sheaths. Statistical analysis was done by Friedman's analysis of variance (p < 0.05). RESULTS: There was a progressive and significant decrease in tension along the stages (Friedman's analysis of variance, p < 0.001). Traction indexes were higher in the initial stage and became gradually lower along the other stages. CONCLUSION: The undermining of the anterior rectus sheaths helps to decrease tension during the components separation technique. LEVEL OF EVIDENCE: Level V, experimental study.