Suturing methods in prolapse surgery: a biomechanical analysis

Pelvic organ prolapse is a common problem in urogynecological surgery. Abdominal and laparoscopic sacrocolpopexy is currently considered to be the gold standard of treatment. The main problem remains the anatomical point of fixation as well as how sutures are placed. We evaluated the biomechanical difference between an in-line ligament suture versus an orthogonal ligament suture and a single suture versus a continuous suture at the anterior longitudinal ligament in an in-vitro, sacrocolpopexy model.

Biomechanical in-vitro testing was performed on human, non-embalmed, female cadaver pelvises. An Instron test frame (tensinometer) was used for load/ displacement analysis. The average patient age was 75 years. Ligament preparation yielded 15 ligaments available for testing. Recorded parameters were the ultimate load, failure displacement, and stiffness.

This in-vitro analysis of different suturing methods showed the difference between an orthogonal and an in-line approach to be the ultimate load. Orthogonal sutures displayed an ultimate load of 80 N while in-line suturing yielded only 57 N (p < 0.05). For the anterior longitudinal ligament, this study demonstrated that continuous suture is significantly superior to a single suture regarding failure displacement (p < 0.05).

We established baseline biomechanical parameters for the sacrospinous ligament and anterior longitudinal ligament. An orthogonal suture is superior to an in-line suture in an in-vitro model. A continuous suture is superior to a single suture at the anterior longitudinal ligament. Clinical trials might be able to evaluate whether any clinical significance can be established from these findings.