title: Changes in the interfacial shear resistance of disc annulus fibrosus from genipin crosslinking.
abstract: Crosslinking soft tissue has become more common in tissue engineering applications, and recent studies have demonstrated that soft tissue mechanical behavior can be directly altered through crosslinking. Using a recently reported test method that shears adjacent disc lamella, the effect of genipin crosslinking on interlamellar shear resistance was studied using in vitro bovine disc annulus. Specimens of adjacent lamella were dissected from four discs taken from three fresh frozen bovine tails. These specimens were paired and soaked in either 50 mM EPPS Phosphate (ph9) with 20 mM genipin at 37 °C for 4 h or in 50 mM EPPS Phosphate (ph9) of which twelve specimens (6 per treatment) were successfully tested and analyzed. Crosslinked specimens were noted to have significantly higher yield force per width (59%), peak force per width (70%), and resilience (69%) compared to sham treated controls, supporting the hypothesis that genipin crosslinking increases the resistance to interlamellar shear of the annulus interface. Additionally, a possible dependency may exist between the interlamellar shear strength and neighboring lamella because of the bridging fiber network previously described by other investigators.
authors.affiliation: Orthopeutics LP, 1704 Deepwood Dr, Round Rock, 78681, USA; Texas A&M University Department of Biomedical Engineering, USA. Electronic address: kirking@sbcglobal.net.
authors.forename: Bryan
authors.initials: B
authors.lastname: Kirking
authors.affiliation: Orthopeutics LP, 1704 Deepwood Dr, Round Rock, 78681, USA; University of Kentucky, Department of Neurosurgery and Biomedical Engineering, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hedman
authors.affiliation: Texas A&M University Department of Biomedical Engineering, USA.
authors.forename: John
authors.initials: J
authors.lastname: Criscione
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002417:Cattle; D003432:Cross-Linking Reagents / Q000737:chemistry; D007403:Intervertebral Disc / Q000502:physiology*; D039823:Iridoids / Q000737:chemistry*; D033081:Shear Strength; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods*
chemical_list: D003432:Cross-Linking Reagents; D039823:Iridoids; C007834:genipin
keywords: Crosslinking; Disc; Genipin; Interfacial shear; Lamella; Lamellar shear