Calibration of a Sensate Bone Regeneration Scaffold

Abstract

Long bone defects can cause complex challenges to both doctor and patient. Current clinical strategies for treating patients with long bone segment defects are very poor. Sensate implantable biomimetic polybutylene terephthalate (PBT) scaffolds develop faster and more complete bone ingrowth than simple porous scaffolds with the same pore size and overall porosity. They have provided the opportunity to monitor healing and could be used to study regeneration of bone in defects. Previous studies have successfully created small sensate scaffolds for canine femoral condylar resurfacing in the stifle joint (the knee). The shape and size of these scaffolds could be modified to act as bone supporting scaffolds for larger segment bone regeneration. Sensors on these scaffolds could be used to determine loading and detect healing as bone ingrowth occurred. A biomimetic scaffold was wired and loaded to 250 N. The stiffness of this porous segmental replacement scaffold was found to be lower than the modulus of the material. A sheep bone was wired and loaded with compression to 250 N, and with cantilever bending to 50 N. The stiffness was found to be similar to previously reported stiffness for sheepfemora. Limitations to the study include the irregular size, shape, and composition of the sheep bone, as well as differences in loading compared to a human bone.