title: Evaluation of absorbable mesh fixation devices at various deployment angles.
abstract: BACKGROUND
  Hernia repair failure may occur due to suboptimal mesh fixation by mechanical constructs before mesh integration. Construct design and acute penetration angle may alter mesh-tissue fixation strength. We compared acute fixation strengths of absorbable fixation devices at various deployment angles, directions of loading, and construct orientations.
  
  
  METHODS
  Porcine abdominal walls were sectioned. Constructs were deployed at 30°, 45°, 60°, and 90° angles to fix mesh to the tissue specimens. Lap-shear testing was performed in upward, downward, and lateral directions in relation to the abdominal wall cranial-caudal axis to evaluate fixation. Absorbatack™ (AT), SorbaFix™ (SF), and SecureStrap™ in vertical (SSV) and horizontal (SSH) orientations in relation to the abdominal wall cranial-caudal axis were tested. Ten tests were performed for each combination of device, angle, and loading direction. Failure types and strength data were recorded. ANOVA with Tukey-Kramer adjustments for multiple comparisons and χ (2) tests were performed as appropriate (p < 0.05 considered significant).
  
  
  RESULTS
  At 30°, SSH and SSV had greater fixation strengths (12.95, 12.98 N, respectively) than SF (5.70 N; p = 0.0057, p = 0.0053, respectively). At 45°, mean fixation strength of SSH was significantly greater than SF (18.14, 11.40 N; p = 0.0002). No differences in strength were identified at 60° or 90°. No differences in strength were noted between SSV and SSH with different directions of loading. No differences were noted between SS and AT at any angle. Immediate failure was associated with SF (p < 0.0001) and the 30° tacking angle (p < 0.01).
  
  
  CONCLUSIONS
  Mesh-tissue fixation was stronger at acute deployment angles with SS compared to SF constructs. The 30° angle and the SF device were associated with increased immediate failures. Varying construct and loading direction did not generate statistically significant differences in the fixation strength of absorbable fixation devices in this study.
authors.affiliation: Department of Surgery, Section of Minimally Invasive Surgery, Washington University School of Medicine, 660 South Euclid Avenue, Campus Box 8109, St. Louis, MO, 63110, USA.
authors.forename: Ahmed M
authors.initials: AM
authors.lastname: Zihni
authors.forename: Jaime A
authors.initials: JA
authors.lastname: Cavallo
authors.forename: Dominic M
authors.initials: DM
authors.lastname: Thompson
authors.forename: Nabeel H
authors.initials: NH
authors.lastname: Chowdhury
authors.forename: Margaret M
authors.initials: MM
authors.lastname: Frisella
authors.forename: Brent D
authors.initials: BD
authors.lastname: Matthews
authors.forename: Corey R
authors.initials: CR
authors.lastname: Deeken
mesh_terms: D034861:Abdominal Wall / Q000601:surgery*; D000818:Animals; D001672:Biocompatible Materials; D005260:Female; D046449:Hernia, Abdominal / Q000601:surgery*; D059685:Herniorrhaphy / Q000295:instrumentation* / Q000379:methods*; D013526:Surgical Mesh; D013552:Swine; D013718:Tensile Strength
chemical_list: D001672:Biocompatible Materials