Machining-induced thermal damage in cortical bone: Necrosis and micro-mechanical integrity

In bone cutting, the tissue is exposed to necrosis due temperature elevation, which can significantly influence postoperative results in orthopaedic surgeries. This damage usually revealed through histological analysis show necrotic extent; however, this technique does not capture mechanical damage, essential for a full material integrity assessment. Here, with micro-mechanics, it demonstrated that machining-induced extends beyond region. Drilling different conditions was performed on ex-vivo bovine cortical bone, inducing degrees. Micro-pillar compression tests were machined sub-surface identify changes properties and failure modes caused by drilling. It at high cutting temperatures, near surface suffers from lower modulus (?42%), strength (?41%) brittle behaviour, whereas bulk remains undamaged pristine ductile behaviour. Histology also evaluate and, surprisingly, found weaker layer more than three times larger when compared layer, clearly showing drilling thermo-mechanical effect could affect only biologically, but micro-mechanically. Consequently, these reveal another kind of has so far been neglected.