Cina Mehrvar1, Paul Kuzyk2, Gideon Cohen3, Oleg Safir2, Paul Zalzal4, Adel Alhalawani1, Mark R Towler1, Marcello Papini5. 1. Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria St, Toronto, ON M5B 2K3, Canada. 2. Division of Orthopaedic Surgery, Mount Sinai Hospital, 600 University Ave, Toronto, ON M5G 1X5, Canada. 3. Division of Cardiac Surgery, Sunnybrook Hospital, 2075 Bayview Ave, Toronto, ON M4N 3M5, Canada. 4. Oakville Trafalgar Memorial Hospital, 3001 Hospital Gate, Oakville, ON L6M 0L8, Canada; Faculty of Medicine, Department of Surgery, McMaster University, 1200 Main St W, Hamilton, ON L8N 3Z5, Canada. 5. Department of Mechanical and Industrial Engineering, Ryerson University, 350 Victoria St, Toronto, ON M5B 2K3, Canada. Electronic address: mpapini@ryerson.ca.
Abstract
BACKGROUND: Cerclage wires remain the current standard of care following median sternotomy, despite significant complications including dehiscence and infection. This study uses a human cadaveric model to investigate the use of glass polyalkenoate cements formulated from two glasses, A (mole fraction: SiO2:0.48, ZnO:0.36, CaO:0.12, SrO:0.04) and B (mole fraction: SiO2:0.48, ZnO:0.355, CaO:0.06, SrO:0.08, P2O5:0.02, Ta2O5:0.005), to improve wired sternal fixation. METHODS: Median sternotomies were performed on fifteen cadaveric sterna. Fixation was performed with either traditional wire cerclage or adhesive-enhanced wire cerclage; the adhesive based on either Glass A or Glass B. Cyclic tensile loading of 10 N to 100 N was applied. Every 30 cycles, the maximum load was increased by 100 N up to a maximum of 500 N. Two adhered sterna were tested beyond 500 N. Mid-sternal displacement was measured to assess fixation stability. FINDINGS: Displacement for adhesive-enhanced sternal closures were significantly less (p < 0.05) than standard wire cerclage. There was no significant difference between adhesives. Up to 500 N, no adhesive-enhanced sternum experienced a pathological sternal displacement (>2 mm), while three out of five of traditional wire fixations did. Of the two adhered samples tested beyond 500 N, one showed pathological displacement at 800 N and the other at 1100 N. Failure of adhered sterna appeared to initiate within the trabecular bone rather than in the adhesive. INTERPRETATION: The adhesives were capable of providing immediate bone stability, significantly reducing sternal displacement. In vivo investigations are warranted to determine the effect the adhesives have on bone remodelling.
BACKGROUND: Cerclage wires remain the current standard of care following median sternotomy, despite significant complications including dehiscence and infection. This study uses a human cadaveric model to investigate the use of glass polyalkenoate cements formulated from two glasses, A (mole fraction: SiO2:0.48, ZnO:0.36, CaO:0.12, SrO:0.04) and B (mole fraction: SiO2:0.48, ZnO:0.355, CaO:0.06, SrO:0.08, P2O5:0.02, Ta2O5:0.005), to improve wired sternal fixation. METHODS: Median sternotomies were performed on fifteen cadaveric sterna. Fixation was performed with either traditional wire cerclage or adhesive-enhanced wire cerclage; the adhesive based on either Glass A or Glass B. Cyclic tensile loading of 10 N to 100 N was applied. Every 30 cycles, the maximum load was increased by 100 N up to a maximum of 500 N. Two adhered sterna were tested beyond 500 N. Mid-sternal displacement was measured to assess fixation stability. FINDINGS: Displacement for adhesive-enhanced sternal closures were significantly less (p < 0.05) than standard wire cerclage. There was no significant difference between adhesives. Up to 500 N, no adhesive-enhanced sternum experienced a pathological sternal displacement (>2 mm), while three out of five of traditional wire fixations did. Of the two adhered samples tested beyond 500 N, one showed pathological displacement at 800 N and the other at 1100 N. Failure of adhered sterna appeared to initiate within the trabecular bone rather than in the adhesive. INTERPRETATION: The adhesives were capable of providing immediate bone stability, significantly reducing sternal displacement. In vivo investigations are warranted to determine the effect the adhesives have on bone remodelling.
Authors: Kai O Böker; Katharina Richter; Katharina Jäckle; Shahed Taheri; Ingo Grunwald; Kai Borcherding; Janek von Byern; Andreas Hartwig; Britt Wildemann; Arndt F Schilling; Wolfgang Lehmann Journal: Materials (Basel) Date: 2019-11-30 Impact factor: 3.623