Inspired by tug-of-war,a game-changing bone-tendon fixation paradigm was developed.Specifically,injectable citrate-based bioactive self-expansive and planar-fixing screw(iCSP-Scr)consisting of reactive isocyanate(NCO)...Inspired by tug-of-war,a game-changing bone-tendon fixation paradigm was developed.Specifically,injectable citrate-based bioactive self-expansive and planar-fixing screw(iCSP-Scr)consisting of reactive isocyanate(NCO)terminalized citrate-based polyurethane,proanthocyanidin modified hydroxyapatite(HAp)and water(with/without porogen)was developed and administrated in the bone-tendon gap.Instead of the“point to point”tendon fixation by traditional interface screws,along with the moisture-induced crosslinking and expansion of iCSP-Scr within the confined space of the irregularly shaped bone-tendon gap,the tendon graft was evenly squeezed into the bone tunnel in a“surface to surface”manner to realize strong and stable bone-tendon fixation via physical expansion,mechanical interlocking and chemical bonding(between–NCO and the–NH2,–SH groups on bone matrix).The optimized iCSP-Scr exhibited rapid crosslinking,moderate expansion rate,high porosity after crosslinking,as well as tunable elasticity and toughness.The iCSP-Scr possessed favorable biodegradability,biocompatibility,and osteoinductivity derived from citrate,PC and HAp,it was able to promote osteogenesis and new bone growth inward of bone tunnel thus further enhanced the bone/iCSP-Scr mechanical interlock,ultimately leading to stronger tendon fixation(pull-out force 106.15±23.15 N)comparing to titanium screws(93.76±17.89 N)after 14 weeks’ACL reconstruction in a rabbit model.The iCSP-Scr not only can be used as a self-expansive screw facilitating bone-tendon healing,but also can be expanded into other osteogenic application scenarios.展开更多
基金Youth Talent of Guangdong Special Support Program(0620220207)Natural Science Foundation of China(Grant Nos.U21A2099,82272453,and 82102545)+2 种基金China Postdoctoral Science Foundation(Grant No.2022M721515)Basic and Applied Basic Research Project of Guangzhou City(202201011774)Open Program from Guangdong Provincial Key Laboratory of Bone and Joint Degeneration Disease.
文摘Inspired by tug-of-war,a game-changing bone-tendon fixation paradigm was developed.Specifically,injectable citrate-based bioactive self-expansive and planar-fixing screw(iCSP-Scr)consisting of reactive isocyanate(NCO)terminalized citrate-based polyurethane,proanthocyanidin modified hydroxyapatite(HAp)and water(with/without porogen)was developed and administrated in the bone-tendon gap.Instead of the“point to point”tendon fixation by traditional interface screws,along with the moisture-induced crosslinking and expansion of iCSP-Scr within the confined space of the irregularly shaped bone-tendon gap,the tendon graft was evenly squeezed into the bone tunnel in a“surface to surface”manner to realize strong and stable bone-tendon fixation via physical expansion,mechanical interlocking and chemical bonding(between–NCO and the–NH2,–SH groups on bone matrix).The optimized iCSP-Scr exhibited rapid crosslinking,moderate expansion rate,high porosity after crosslinking,as well as tunable elasticity and toughness.The iCSP-Scr possessed favorable biodegradability,biocompatibility,and osteoinductivity derived from citrate,PC and HAp,it was able to promote osteogenesis and new bone growth inward of bone tunnel thus further enhanced the bone/iCSP-Scr mechanical interlock,ultimately leading to stronger tendon fixation(pull-out force 106.15±23.15 N)comparing to titanium screws(93.76±17.89 N)after 14 weeks’ACL reconstruction in a rabbit model.The iCSP-Scr not only can be used as a self-expansive screw facilitating bone-tendon healing,but also can be expanded into other osteogenic application scenarios.