Characterization of the mechanical properties of demineralized bone

Demineralized bone has had limited use as a medical implant, although, recently Jackson et al. (Am J Sports Med 1996;24(4):405-414) examined using demineralized bone as an anterior cruciate ligament (ACL) replacement and found that within 1 year the demineralized bone had remodeled from a haversian system (bone-like) into a ligament-like structure. Little research has been done to characterize the mechanical properties of demineralized bone and examine its potential as a ligament replacement. This research examined the mechanical properties of demineralized bone as a function of acid saturation time and methods of processing and sterilization using specimens from various anatomic locations. Bone specimens were manufactured from the tibia, metatarsus, femur, radius, and humerus of bovine bone. Tensile strength, strain, and modulus of elasticity were examined for various acid saturation times and sterilization treatments. Additionally, viscoelastic properties, creep and stress relaxation, and fatigue properties were examined. The findings indicate that completely demineralized bone has mechanical properties similar to the ACL and, therefore, has increased likelihood for success in ACL reconstruction surgery.