The Mechanical Strength Of A Biphasic Polycaprolactone Bone Scaffold For Medial Open Wedge High Tibia Osteotomy Implantation

Mechanical strength is a requirement of the bone scaffold for osteoarthritis treatment by the medial open wedge high tibia osteotomy (MOWHTO). The mechanical compression of the scaffold which depends on material concentration and structure must be concerned in MOWHTO substitution due to help to prevent the delayed bone healing process from scaffold collapse. This study was divided into two sections: (i) the influence of varying concentrations between DBM-HA mixed PCL scaffold (20/80, 30/70, and 40/60 % wt./wt. DBM-HA/PCL) on compressive strength, and (ii) the compressive strength of the 0°-90° orientations DBM-HA/PCL scaffold (20/80% wt./wt.) constructed with 300-500 μm pore dimension by the extrusion-based bioprinting method. The results exhibited that the concentrations of DBM-HA/PCL affected mechanical properties in the scaffold. The low DBM-HA concentrations scaffold showed high compressive strength. The 20/80 % wt./wt. DBM-HA/PCL represented the 23.25 MPa and 157.63 MPa of compressive stress and modulus respectively. The 0°-90° orientations scaffold with 20/80 % wt./wt. DBM-HA/PCL showed the 2.90-16.03 MPa and 70.92 MPa of compressive stress and modulus. In conclusion, the mechanical compression of 20/80 % wt./wt. DBM-HA/PCL scaffold fabricated with 300-500 μm pore size has a range within tibia cancellous bone and it is suitable for an alternative bone in the MOWHTO.