Background Laparoscopic ventral rectopexy (LVR) is an established technique for the treatment of rectal prolapse. Several techniques and devices can be used for proximal mesh fixation on the sacral promontory during this procedure. The aim of this study was to compare the fixation strength of a recently introduced screw for mesh fixation on the promontory during LVR with two other frequently used techniques. Methods An ex vivo experimental model using a porcine spinal column was designed to measure the strength of proximal mesh fixation. In a laparoscopic box trainer, a polypropylene mesh was anchored on the spinal column using three different fixation methods, i.e., the Protack 5-mm tacker device, Ethibond Excel 2-0 stitches, and the Karl Storz screw. Subsequently, increasing traction was applied to the mesh. This traction was applied at a standardized angle as determined by measuring the mean angle between the site of distal mesh fixation on the rectum and a line straight through the sacral promontory on 12 random dynamic MR scans of the pelvic floor after the LVR procedure. The applied force was measured at the moment that the fixation broke, using a calibrated electronic Newton meter. All fixation methods were tested ten times. Results The mean angle, as measured on the MR scans, was 100°. The mean disruption force, which led to a break of the proximal mesh fixation, was 58 N for the three Protack tacks, 55 N for the two stitches, and 70 N for the new screw. The use of a screw therefore led to a significantly stronger fixation compared to the use of stitches ( p  ≤ 0.05). No significant difference was determined between the tacks and the screw fixation and between the tacks and the stitches fixation. Conclusion The new screw for proximal mesh fixation during LVR procedures offers similar fixation strength when compared to tacks. The use of one screw for proximal mesh fixation is therefore a reasonable alternative to the use of several tacks or sutures.