Is release of the posterior lamella enough? A cadaveric exploration of posterior component separation techniques.

BACKGROUND: As posterior component separation techniques continue to gain popularity there is uncertainty regarding the degree of fascial advancement afforded by the various techniques. Our study seeks to compare the degree anterior rectus sheath translation seen in full transversus abdominus release compared to simple release of the posterior lamella of the rectus sheath. METHODS: Ten hemi-abdomens in five fresh cadavers were dissected. One hemi-abdomen underwent external oblique release. The contralateral hemi-abdomen underwent retrorectus dissection and initial release of the internal lamella of the internal oblique, followed by full transversus abdominus release. A 4 kg weight was suspended from the fascia and excursion was measured after 1) external oblique separation, 2) posterior lamella of the internal oblique separation, and 3) transversus abdominis separation. RESULTS: Average unilateral hemifascial translation after release of the external oblique provided an average unilateral hemi-fascial translation of 3.38 cm (+/- 0.69). Release of the posterior lamella of the internal oblique provided 3.98 cm (+/- 0.94). After transversus release the average translation increased to 4.31 cm (+/- 0.89). CONCLUSIONS: In this cadaveric study, the majority (92%) of fascial advancement afforded by posterior component separation was achieved by an intermediate step in the transversus abdominus release operation: division of the posterior lamella of the internal oblique.

Use of gracilis muscle as a "walking" flap for repair of a rectovaginal fistula.

Rectovaginal fistula is a rare but debilitating complication of a variety of pelvic operations. Management remains challenging with high incidence of failure. The majority of patients eventually require surgical intervention. Several surgical procedures have been described including local repair, muscle transposition, or laparotomy. Among the muscles used for rectovaginal fistula repair, the gracilis muscle interposition flap is an excellent option. However, in a small percentage of cases it fails, and alternative techniques should be entertained. We describe the case of a 50-year-old female who underwent stapled hemorrhoidopexy that was complicated by a 30 mm rectovaginal fistula, and required fecal diversion. Four months later, gracilis muscle interposition flap was performed but failed. The right gracilis flap was then re-used successfully as a "walking" flap. At three months the patient underwent closure of the temporary loop ileostomy, and continues to do well with no evidence of rectovaginal fistula recurrence one year later. To our knowledge, this is the first report of the use of a gracilis muscle as a "walking" flap for repair of a rectovaginal fistula, and should be considered as an alternative appropriate treatment for persistent rectovaginal fistulas after failure of initial gracilis muscle interposition flap.