OBJECTIVE: Intraoperative fascial traction (IFT) for the treatment of large ventral hernias and loss of domain (LOD) hernias is a promising tool in abdominal wall surgery. However, little is known about the extent of gain in myofascial advancement especially for the anterior rectus sheath. We, therefore, used a cadaveric model to determine the medialization during IFT.
METHODS: 4 fresh frozen specimens were used. Retromuscular preparation was carried out followed by IFT with diagonal vertical traction for 30 min. Medial advancement of the anterior rectus sheath was measured after 15 and 30 min as well as traction forces.
RESULTS: Total medialization for anterior rectus sheath after 30 min of IFT was 10.5 cm (mean). The mean traction force was 16.28 kg. Total medialization was significantly higher during the first 15 min of vertical fascial traction (p < 0.05).
CONCLUSIONS: IFT provides significant medialization for the anterior rectus sheath in the cadaveric model. The findings align with results from a retrospective case study. Therefore, we see IFT as a beneficial tool in abdominal wall surgery.

Component separation remains an integral step during ventral hernia repair. Although a multitude of techniques are described, anterior component separation (ACS) via external oblique release (EOR) and posterior component separation (PCS) via transversus abdominis muscle release (TAR) are commonly utilized. The extent of myofascial medialization after ACS or PCS has not been well elucidated. We conducted a comparative analysis of ACS versus PCS in an established cadaveric model.
Fifteen cadavers underwent both ACS via EOR and PCS via TAR. Following midline laparotomy (MLL), baseline myofascial elasticity was measured. Steps for ACS included creation of subcutaneous flaps (SQF), external oblique release (EOR), and retrorectus dissection (RRD). For PCS, steps included retrorectus dissection (RRD), transversus abdominis muscle division (TAD), and retromuscular dissection (RMD). Maximal advancement of anterior rectus fascia (ARF) was measured following application of tension to the fascia as a whole, and separately at upper, middle, and lower segments. Statistical analysis was performed with Mann-Whitney U test. Values are represented as average myofascial medialization in centimeters.
Following MLL an average of 5.0 ± 0.9 cm (range 3.4-6.0 cm) of baseline medialization was obtained. Complete ACS provided 8.8 ± 1.2 cm (range 6.3-10.7 cm) of ARF advancement compared to 10.2 ± 1.7 cm (range 7.6-12.7 cm) with PCS, p = 0.046. In the upper and mid-abdomen, we noted increased ARF advancement with PCS versus ACS (8.1 ± 1.4 cm vs. 6.7 ± 1.2 cm and 11.4 ± 1.5 vs. 9.6 ± 1.4 cm, respectively, p = 0.01). Similar levels of ARF advancement were observed in the lower abdomen, 9.1 ± 1.7 cm versus 8.7 ± 1.8 cm, p = 0.535.
Component separation via both anterior and posterior approaches provide substantial myofascial advancement. In our model, we noted statistically greater anterior fascial medialization after PCS versus ACS as a whole, and especially in the upper and mid-abdomen. We advocate PCS as a reliable and possibly superior alternative for linea alba restoration for reconstructive repairs, especially for large defects in the upper and mid-abdomen.

Posterior component separation (PCS) via the transversus abdominis release (TAR) procedure continues to gain popularity. However, neither the physiologic basis nor the extent of myofascial medialization after TAR is established. We aimed to assess both anterior and posterior rectus fascia (AF and PF) medialization following each step of the TAR procedure.
Ten fresh cadavers underwent PCS via TAR. Steps included midline laparotomy (MLL), retrorectus dissection (RRD), incision of the posterior rectus sheath (IPL), transversus abdominis muscle division (TAD), and retromuscular dissection (RMD). Medial advancement of AF and PF was measured following application of 2.5, 5.0 lb, and maximal tension to the fascial edge. Values are represented as mean advancement past midline in centimeters.
MLL allowed advancement of 2.5, 3.7, and 4.9 cm. RRD provided advancement of 4.1, 5.9, and 7.6 cm for AF and 4.4, 6.2, and 7.5 cm for PF. IPL provided advancement of 4.2, 6.1, and 8.0 cm for AF and 4.6, 6.6, and 8.3 cm for PF. TAD provided advancement of 4.5, 6.6, and 8.6 cm for AF and 5.3, 7.5, and 9.5 cm for PF. RMD provided advancement of 5.5, 7.9, and 9.9 cm for AF and 6.9, 9.6, and 11.2 cm for PF. Overall, the complete TAR procedure provided AF advancement of 102% and PF advancement of 129%, over baseline.
The TAR procedure provides for substantial medial advancement of both anterior and posterior myofascial components of the abdominal wall. Retromuscular dissection deep to the divided transversus abdominis muscle appears to be the key step of the procedure, allowing for effective reconstruction of very wide (≈ 20 cm) defects.