Abstract
Introduction
In recent years, there has been a growing interest, in many fields of medicine, in the use of bone adhesives that are biodegraded to non-toxic products and resorbed after fulfilling their function in contact with living tissue. Biomechanical properties of newly developed bone glue, such as adhesion to bone and elastic modulus were tested in our study.
Material and methods
Newly developed injectable biodegradable “self-setting” bone adhesive prepared from inorganic tricalcium phosphate powder and aqueous solution of organic thermogelling polymers was used for ex-vivo fixing fractured pig femur. Ex-vivo biomechanical tests were performed on 45 fresh pig femurs. Control group consist of 10 healthy bones, tested group was created by 35 bones with artificial fractures in diaphysis – oblique (O) and bending wedge (BW) type of fracture. Tested group were divided to following 4 subgroups (sg); sg1 – O fracture (n=15) glued together with 3 different type of bone adhesives, sg2 BW fracture (n=5) glued together with bone adhesive (n=5); sg3 – BW fracture fixed with locking compression plate (LCP), n=5; sg4 – BW fracture fixed with LCP in combination with bone adhesive. Three-point bending force and shear compression tests were performed on linear electrodynamic test instrument (ElectroPuls E10000, Instron). Femurs from sg1, sg2 and sg4 were tested on Micro-CT before and after biomechanical testing.
Results
Shear compression tests in sg1 without amino acids modification showed that it is needed force of 0.5 mPa to recreate fracture, however, modification with amino acids increased glue strength to 3 mPa. Three-point bending force test in sg2 showed reduced force of 250 N to recreate fracture, anyhow in sg4 force needed to initiate the fracture was increased up to 5000 N.
Conclusion
Newly developed injectable biodegradable “self- setting” bone adhesive represents new possibility how to fix small bone fragments in comminuted fractures and simultaneous chance how to improve and accelerate bone healing process.
Acknowledgement
Project no. AOTEU-R-2016-064 was supported by AOTRAUMA, Switzerland