Mechanical and Histological Characteristics of Phasix™ ST Mesh in a Porcine Model of Hernia Repair

Abstract

Purpose: The objective of this study was to determine mechanical and histological properties of Phasix TM ST Mesh in various defect sizes and characterize the tissue replacing Phasix TM ST Mesh in a porcine model of ventral hernia repair. Methods: Simulated hernia defects were surgically created in the midline of twenty-four (n ¼ 24) Yucatan pigs. Treatment groups included 8 cm defect sutured closed (buttress) and unclosed 4 cm and 8 cm defect groups. Phasix TM ST Mesh (15 cm diameter circle) was implanted laparoscopically and fixated circumferentially with SorbaFix TM Absorbable Fixation System fasteners. The repair sites underwent mechanical, molecular weight, and histological evaluation at 48 and 72 weeks postimplantation. Results: Mechanical testing of Phasix TM ST Mesh-repaired sites revealed similar strengths at both time points for all three repair types, p > 0.05 in all cases (48 weeks: 142.4 ± 6.0 N, 142.3 ± 16.5 N, and 168.8 ± 38.5 N; 72 weeks: 110.0 ± 18.3 N, 138.6 ± 42.2 N, and 160.6 ± 42.0 N for 4 cm defect, 8 cm defect, and 8 cm buttress, respectively. mean ± SEM) No significant differences were observed over time except at 72 weeks postimplantation when the 4 cm defect group exhibited significantly lower strength than the T 0 strength of Phasix TM ST Mesh (204.6 ± 5.0 N, p < 0.05). The molecular weight of Phasix TM ST Mesh decreased over time, regardless of repair type. Histological analysis showed comparable mature collagen/fibrovascular tissue around and within the Phasix TM ST Mesh interstices, including the segment of mesh overlying the defect. Conclusion: Phasix TM ST Mesh-repaired sites exhibited similar mechanical strengths and histological properties across all defect sizes in this porcine model.

Fully resorbable poly-4-hydroxybutyrate (P4HB) mesh for soft tissue repair and reconstruction: A scoping review

“…Fourteen publications identified by this scoping review involved preclinical studies in a variety of animal models and species, including pigs, rats, rabbits, sheep, mice, and vervets (Figure 2, and Table 1) (6,23,24,26,36,37,(43)(44)(45)(46)(47)(48)(49)89). Three of these studies (n = 3) contained both a benchtop component and a preclinical component (6,36,37).…”

“…Preclinical studies demonstrate long-term resorption of P4HB over a period of approximately 12–18 months, during which the mesh loses all of its mechanical strength ( 6 , 43 , 44 , 47 ). The clinical studies identified in this literature review provided insight into the performance of P4HB in a variety of patient populations and clinical scenarios.…”

The Transition from Experimental Data to Clinical Practice Using P4HB Mesh in Ventral Hernia Repair

“…In this paper, the authors compare the longer term results of using a P4HB mesh with an anti-adhesive visceral protective layer during laparoscopic repair in a pig model. 6 Different types of hernia defects were created, 8 cm diameter with defect closure, and both 4 and 8 cm hernias without defect closure; all were treated with a circular 15 cm diameter P4HB-ST mesh. A little bit surprisingly, all repaired hernia sites exhibited similar mechanical strength as well as histological properties, independent of both hernia size, defect closure, and follow-up time (48 and 72 weeks after implantation).…”

Assessment of mesh shrinkage using fibroblast-populated collagen matrices: a proof of concept for in vitro hernia mesh testing

“…Currently there are over one hundred mesh variations on the market [ 2 ], including conventional synthetic meshes as well as newer biological products. More recently, industry has continued this innovation by developing new absorbable “biosynthetic” meshes [ 3 ].…”