Barbed Suture Strength in Sacrocolpopexy: Does Pattern Matter?

Objectives: This study aims to compare the structural properties of three different barbed suture attachment patterns used to fixate mesh to the vagina during sacrocolpopexy.

Methods: Segments of type 1 polypropylene mesh (Restorelle; Coloplast, Humlebaek, DK) measuring 6 x 3 cm were affixed to rectus abdominis fascia obtained from five fresh frozen female cadavers. Barbed 6-inch 2-0 polydioxanone (Stratafix; Ethicon, Raritan, NJ) with three different attachment patterns and non-barbed 2-0 polydioxanone were used for fixation.

Barbed suture attachment patterns included a circular, horizontal, and vertical. In the circular technique, mesh was attached to the fascia along the perimeter of the mesh circumferentially with final fixation vertically in the midline. In the horizontal technique, mesh was attached to the fascia in a zig zag extending from one lateral edge to the other for three rows. In the vertical technique, mesh was attached to the fascia in a zig zag extending from the distal to proximal edge for three columns.

Mechanical testing was carried out using a uniaxial electromechanical testing system (TestResources 100R500; Eden Prairie, MN). Samples were secured with the mesh at a 0 degree offset in the upper tensile grips and the tissue in the lower tensile grips. Samples were loaded in tension at a displacement rate of 0.5 mm/sec until failure of either the tissue or the mesh was observed. Stiffness (N/mm), ultimate load (N), load at failure (N), extension at failure (mm), and energy to failure (N*mm) were determined from the load vs. displacement curves using a custom MATLAB script. Failure was defined in the analysis by a drop in the measured load between consecutive datapoints of at least 10% and 3N. Statistical analyses were performed using one-way ANOVA and post-hoc multiple comparisons tests were performed using Tukey’s test.

Results: Tensile testing revealed similar mechanical performance across all groups. While no statistically significant effects of suture technique on stiffness, ultimate load, or extension at failure were observed, a statistically significant increase in ultimate load was found for the horizontal group compared to the vertical group (p= 0.0459) in the post-hoc analysis. Additionally, a statistically significant effect of suture technique on load at failure (p = 0.0188) and energy at failure (p = 0.0435) was identified. Post-hoc analysis showed a statistically significant increase in the load at failure for the horizontal group compared to the vertical group (p = 0.0117), with no differences found in energy to failure between groups.

Conclusions: Overall, no difference was observed when comparing all suture attachment patterns. However, a statistically significant difference in ultimate load and load at failure favored the horizontal attachment over the vertical attachment. Furthermore, there was no difference observed when comparing non-barbed interrupted suture attachment to the three barbed suture attachment patterns.