Comparison of Tensile Strength and Early Healing of Self-Locking and Surgeon’s Knots for Closure of Ventral Midline Celiotomy in Horses

Abstract

Characteristics of surgical closure are associated with incisional complications. The surgical knot has been shown to be the weakest point of the suture line. Self-locking knots, such as the forwarder (F) and Aberdeen (A) knot, have been investigated in vitro and ex vivo, supporting their superior knot strength and higher bursting pressures. We hypothesized that a ventral midline celiotomy (VMC) closure using a forwarder-Aberdeen (F-A) self-locking knot combination would have greater tensile strength and improved wound healing when compared to the traditional surgeon’s-surgeon’s (S-S) knot combination in vivo. Fourteen horses underwent a VMC, closed with either F-A or S-S knot combination. Incisions were subjectively graded for healing quality. Biomechanical testing was performed and histologic grading from each subject following humane euthanasia ten days post VMC. Statistical analysis showed no difference between groups for tensile strength (p=0.97) location of failure (p=0.24), and wound healing (p=0.60). However, the F-A group failed more frequently (15/21, 71%) along the rectus sheath compared to S-S (6/21, 26%), consistent with normal linea alba. Similar tensile strength and histologic healing shows either knot combination provides secure closure in horses for the early post-operative period following VMC. Results support a randomized prospective clinical trial to evaluate performance of the F-A self-locking knot combination in clinical cases with long-term follow-up to further support clinical use.