No abstract

No abstract

Objectives: Over the past decade, the use of topical skin adhesives (TSA) for wound closure has increased. Among TSA characteristics, strength and flexibility are most important. Prior studies have compared the wound bursting strengths (WBSs) of the cyanoacrylates immediately after wound closure. In this study the authors compared the WBS and flexibility of multiple TSAs immediately and up to 2 days after closure.Methods: This was a controlled animal experiment. Two-centimeter incisions were created on both sides of 210 Sprague-Dawley rats and randomly closed with one of five commercially available TSAs). WBS and TSA flexibility were measured using the BTC-2000 device immediately after closure and at 1 and 2 days after closure. WBS and TSA flexibility were compared across groups with analysis of variance (ANOVA).Results: Wound bursting strengths were higher (p < 0.05) at 0, 1, and 2 days for D (274, 388, 232 mm Hg) than for all other TSAs (I 182, 225, and 107; H 189, 214, and 69; L 146, 118, and 75; or G 161, 150, and 73). TSA flexibility was also greater (p < 0.05) at 0, 1, and 2 days for D (36, 27, and 29 mm Hg ⁄ mm) than for all other TSAs (I 18, 14, and 12; H 18, 13, and 15; L 19, 14, and 12; G 26, 23, and 18). Conclusions:The octyl-cyanoacrylate-based adhesive is significantly stronger and more flexible than all the butyl-cyanoacrylate-based adhesives at 0, 1 and 2 days after closure.ACADEMIC EMERGENCY MEDICINE2008; 15:1290-1294 ª

No abstract

No abstract

Based on the in vivo biomechanical testing and histological results, no evidence of impedance to wound healing was detected.

The mechanical properties of the human lumbar anterior longitudinal ligament were investigated, and the influence of aging, disc degeneration, and vertebral bone density on these properties was determined. Tensile mechanical properties of the vertebra-anterior longitudinal ligament-vertebra complex were determined for 16 segments from cadavera of individuals who had been 21-79 years old (mean, 52.1 years) at the time of death. Regional strain patterns associated with three sites across the width and three sites along the length of the anterior longitudinal ligament were measured with use of a video-based motion analysis system. In the young, normal anterior longitudinal ligament, the elastic moduli of the insertion and substance regions of the ligament were similar (approximately 500 MPa). During aging (21-79 years), the elastic modulus of the substance region increased 2-fold, whereas the elastic modulus of the insertion decreased 3-fold; this resulted in an approximately 5-fold difference in elastic modulus between these regions in the older spine. The strength of the bone-ligament complex decreased approximately 2-fold (from 29 to 13 MPa) over this same age range. The outer portion of the anterior longitudinal ligament consistently had the highest peak tensile strains (11.8 +/- 2.7%) in all of the specimens examined. Preparations with nondegenerated discs and high bone density were significantly stronger (66%) and failed in the ligament substance; in contrast, segments from older individuals with degenerated discs and lower bone density failed in the ligament insertion regions.

Biomechanical studies of wound strength are important because of new investigations in growth factors, cytokines, and fetal wounds. We compared two traditional methods of wound disruption measurement with a novel computerized model designed for in vivo experiments. An Instron tensiometer (INSTS) and an air insufflated positive pressure device (AIPPD) were compared with a vacuum-controlled wound chamber device (VCWCD). The VCWCD produced vacuum at the wound site and wound disruption was monitored with two video camera/recorders. Rats were marked with a template guide for a 2.5 cm, full-thickness, abdominal incisional wound. Rats were divided into three groups and studied at 2, 7, or 14 days after wounding. The recorded images were computer digitalized to generate wound strength curves from a three-dimensional model. A comparison of the wound disruption curves demonstrated that the VCWCD was comparable to the INST or AIPPD in normal wound healing (P greater than .40). The VCWCD provided data with less standard error at 2 days after wounding (P less than 05). In separate series of experiments, VCWCD was tested in the early phases of healing and was found to be sensitive to change at intervals of 48 hr after wounding (P less than .005). The INST or AIPPD methods could not perform this task because of an unacceptable level of random error after tissue manipulation. The VCWCD system was considered superior for evaluating early wound healing because it was an in vivo method which required minimal wound manipulation.