Highly Customizable Bone Fracture Fixation through the Marriage of Composites and Screws

• Published in: Advanced functional materials Vol. 31; no. 41
• Main Authors: Hutchinson, Daniel J., Granskog, Viktor, Kieseritzky, Johanna, Alfort, Henrik, Stenlund, Patrik, Zhang, Yuning, Arner, Marianne, Håkansson, Joakim, Malkoch, Michael
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc 2021
• Subjects: Adhesion; Adverse effect; Bend strength; Bending rigidity; biomaterials; Biomaterials Science; Biomaterialvetenskap; Bone; bone fixation; Bone-fracture fixation; Chemistry; complications; Coupling chemistry; Customizability; epidemiology; Femur; Fixation; Flexing; Fracture; Fracture fixation; Fractures; hand; Hydroxyapatite; injuries; Internal fixation; materials engineering; Materials Science; Medicin och hälsovetenskap; Metal plates; New approaches; Particulate composites; Physics; plate fixation; Polymer matrix composites; Reduction (metal working); Science & Technology - Other Topics; Screws; Surgeons; thiol-ene composites; thiol–ene composites; Tissue; Visible light induced
• ISSN: 1616-301X; 1616-3028; 1616-3028
• DOI: 10.1002/adfm.202105187

Open reduction internal fixation (ORIF) metal plates provide exceptional support for unstable bone fractures; however, they often result in debilitating soft‐tissue adhesions and their rigid shape cannot be easily customized by surgeons. In this work, a surgically feasible ORIF methodology, called AdhFix, is developed by combining screws with polymer/hydroxyapatite composites, which are applied and shaped in situ before being rapidly cured on demand via high‐energy visible‐light‐induced thiol–ene coupling chemistry. The method is developed on porcine metacarpals with transverse and multifragmented fractures, resulting in strong and stable fixations with a bending rigidity of 0.28 (0.03) N m2 and a maximum load before break of 220 (15) N. Evaluations on human cadaver hands with proximal phalanx fractures show that AdhFix withstands the forces from finger flexing exercises, while short‐ and long‐term in vivo rat femur fracture models show that AdhFix successfully supports bone healing without degradation, adverse effects, or soft‐tissue adhesions. This procedure represents a radical new approach to fracture fixation, which grants surgeons unparalleled customizability and does not result in soft‐tissue adhesions. A rapidly curable thiol–ene composite is combined with layers of poly(ethyleneterephthalate) fiber mesh and screw attachments to create a highly customizable fixation method for finger bone fractures, which does not result in soft‐tissue adhesions and can provide similar stability and support as metal plates against forces exceeding those in hand rehabilitation exercises.