ObjectiveTo compare biomechanical properties and mechanism of failure of 3 regions of ventral abdominal wall in cats by using 2 suture materials, 2 suture bite‐to‐stitch intervals (SBSI), and full‐thickness versus fascia‐only closure.Study DesignRandomized, cadaveric, ex vivo mechanical testing.Sample Population16 adult cat cadavers, 3 samples per cat.MethodsThree regions of ventral abdominal wall were mechanically tested (N = 48 samples). Preumbilical, umbilical (U), and postumbilical (POU) regions were harvested by using a template. The thickness of the linea alba was recorded. Six samples without celiotomy served as controls. Twenty‐eight samples were randomized to SBSI (2 × 2 or 5 × 5 mm) and suture material (3‐0 polyglactin 910 or 3‐0 polydioxanone) for simple continuous celiotomy closure. Fourteen samples were randomized to full‐thickness or fascia‐only closure. Samples were tested by linear distraction; tensile strength and mechanism of failure were recorded. Effects of body weight, thickness of linea alba, anatomic region, SBSI, type of closure, and suture material were evaluated by mixed model linear analysis. Load to failure was compared between males and females, full‐thickness and fascia‐only closure by independent t test, with P < .05 considered statistically significant.ResultsThe POU region achieved lower loads to failure. Load to failure was greater in males compared with females. No difference was detected between full‐thickness and fascia‐only closure. Failure most commonly occurred by tearing of suture through tissues. Tissue failure with suture line loosening occurred mainly in the 5 × 5‐mm SBSI group.ConclusionThe POU region is biomechanically weak and may therefore be predisposed to incisional herniation.

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The objective of this study was to compare the bursting strength and characterize the mode of failure of cranial and caudal midline celiotomies closed with 2 suture patterns and an absorbable monofilament suture material. Design: Randomized, cadaveric, ex-vivo mechanical testing. Sample: Feline cadavers (n = 32). Methods: Specimens were randomized into two groups based on the closure technique (small 2 × 2 mm or large 5 × 5 mm suture-bite-stitch-interval [SBSI] groups). Cranial or caudal midline celiotomies, 7.5 cm long, were created. A custom-made polyurethane bladder was inserted into the abdomen, and the celiotomies were closed in a simple continuous pattern using 3-0 polydioxanone. The repair was loaded to failure by inflating the bladder with compressed air. Bursting strength and mode of failure were recorded. Effects of body weight, gender, thickness and width of linea alba, suture-bite-stitch-interval, and location of celiotomy were analyzed using a mixed model analysis and an independent t-test, with P < 0.05 considered statistically significant. Results: There was no difference in bursting strength between cranial and caudal celiotomies. Bursting strength was lower for celiotomies closed with a large SBSI (P = 0.003). Bursting strength was greater in males compared to females (P = 0.003). Twenty five specimens failed distant from celiotomy closure, while 4 failed by fascial tearing at the site of needle penetration. Failure by loosening of the suture line with intact knots only occurred in 3 caudal celiotomies closed with a large SBSI. Gender, body weight and SBSI accounted for 61.5% of variability in bursting strength (P = 0.005). Conclusions: Small SBSI technique was mechanically superior to large SBSI when tested under these loading conditions. Clinical relevance: Supraphysiological pressures were required to cause failure in all specimens. Both small and large SBSI may be clinically applicable for midline celiotomy closure in domestic cats.