Joeri Kok1, Aurimas Širka2, Lorenzo Grassi3, Deepak Bushan Raina4, Šarūnas Tarasevičius2, Magnus Tägil5, Lars Lidgren6, Hanna Isaksson7. 1. Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden. Electronic address: joeri.kok@bme.lth.se. 2. Department of Orthopedics and Traumatology, Lithuanian University of Health Sciences, A. Mickevičiaus g. 9, LT 44307 Kaunas, Lithuania. 3. Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden. Electronic address: lorenzo.grassi@bme.lth.se. 4. Department of Orthopedics, Clinical Sciences, Lund University, Box 118, 221 00 Lund, Sweden. Electronic address: deepak.raina@med.lu.se. 5. Department of Orthopedics, Clinical Sciences, Lund University, Box 118, 221 00 Lund, Sweden. Electronic address: magnus.tagil@med.lu.se. 6. Department of Orthopedics, Clinical Sciences, Lund University, Box 118, 221 00 Lund, Sweden. 7. Department of Biomedical Engineering, Lund University, Box 118, 221 00 Lund, Sweden; Department of Orthopedics, Clinical Sciences, Lund University, Box 118, 221 00 Lund, Sweden. Electronic address: hanna.isaksson@bme.lth.se.
Abstract
BACKGROUND: Available interventions for preventing fragility hip fractures show limited efficacy. Injection of a biomaterial as bone substitute could increase the fracture strength of the hip. This study aimed to show the feasibility of injecting a calcium sulfate/hydroxyapatite based biomaterial in the femoral neck and to calculate the consequent change in strength using the finite element method. METHODS: Five patients were injected with 10 ml calcium sulfate/hydroxyapatite in their femoral neck. Quantitative CT scans were taken before and after injection. Five additional patients with fragility hip fractures were also scanned and the images from the non-fractured contralateral sides were used. Finite element models were created for all proximal femora with and without injection and the models were tested under stance and sideways fall loading until fracture. The change in fracture strength caused by the injection was calculated. Additionally, perturbations in volume, location, and stiffness of the injected material were created to investigate their contribution to the fracture strength increase. FINDINGS: The 10 ml injection succeeded in all patients. Baseline simulations showed theoretical fracture strength increases of 0-9%. Volume increase, change in location and increase in stiffness of the material led to increases in fracture strength of 1-27%, -8-26% and 0-17%, respectively. Altering the location of the injection to a more lateral position and increasing the stiffness of the material led to increases in fracture strength of up to 42%. INTERPRETATION: This study shows that an injection of calcium sulfate/hydroxyapatite is feasible and can theoretically increase the hip's fracture strength.
BACKGROUND: Available interventions for preventing fragility hip fractures show limited efficacy. Injection of a biomaterial as bone substitute could increase the fracture strength of the hip. This study aimed to show the feasibility of injecting a calcium sulfate/hydroxyapatite based biomaterial in the femoral neck and to calculate the consequent change in strength using the finite element method. METHODS: Five patients were injected with 10 ml calcium sulfate/hydroxyapatite in their femoral neck. Quantitative CT scans were taken before and after injection. Five additional patients with fragility hip fractures were also scanned and the images from the non-fractured contralateral sides were used. Finite element models were created for all proximal femora with and without injection and the models were tested under stance and sideways fall loading until fracture. The change in fracture strength caused by the injection was calculated. Additionally, perturbations in volume, location, and stiffness of the injected material were created to investigate their contribution to the fracture strength increase. FINDINGS: The 10 ml injection succeeded in all patients. Baseline simulations showed theoretical fracture strength increases of 0-9%. Volume increase, change in location and increase in stiffness of the material led to increases in fracture strength of 1-27%, -8-26% and 0-17%, respectively. Altering the location of the injection to a more lateral position and increasing the stiffness of the material led to increases in fracture strength of up to 42%. INTERPRETATION: This study shows that an injection of calcium sulfate/hydroxyapatite is feasible and can theoretically increase the hip's fracture strength.
Authors: Hong Xu; Yang Liu; Erdem Aras Sezgin; Šarūnas Tarasevičius; Robin Christensen; Deepak Bushan Raina; Magnus Tägil; Lars Lidgren Journal: J Orthop Surg Res Date: 2022-06-03 Impact factor: 2.677
Authors: Samuel A Hockett; John T Sherrill; Micah Self; Simon C Mears; C Lowry Barnes; Erin M Mannen Journal: J Mech Behav Biomed Mater Date: 2020-12-11
Authors: Erdem Aras Sezgin; Ahmet Toygun Tor; Vėtra Markevičiūtė; Aurimas Širka; Šarūnas Tarasevičius; Deepak Bushan Raina; Yang Liu; Hanna Isaksson; Magnus Tägil; Lars Lidgren Journal: Jt Dis Relat Surg Date: 2021-11-19
Authors: Deepak Bushan Raina; Aurimas Širka; Irfan Qayoom; Arun Kumar Teotia; Yang Liu; Sarunas Tarasevicius; Kathleen Elizabeth Tanner; Hanna Isaksson; Ashok Kumar; Magnus Tägil; Lars Lidgren Journal: Tissue Eng Part A Date: 2020-10 Impact factor: 3.845