Understanding the Effects of Thermal Elevations Associated With Orthopedic Intervention: An Experimental and Computational Investigation

Abstract

Specialized surgical cutting instruments are required to provide orthopedic surgeons with access to joints of the body, without causing extensive harm to native tissue, thus enhancing post-operative outcome. Orthopaedic intervention inevitably exposes bone tissue to elevated temperatures due to mechanical abrasion. Elevated temperatures lead to thermal necrosis and apoptosis of bone cells, surrounding soft tissue, bone marrow and stem cells crucial for postoperative healing (1–4). Thermally damaged bone tissue is subsequently resorbed and in severe cases replaced by connective tissue (2, 5) Bone thermal damage occurs when the local temperature exceeds a thermal threshold, largely recognised as ≥47°C (4, 6). Furthermore, it has been proposed that the area of bone to experience thermal damage is directly proportional to the duration of exposure to the heat source (7, 8). However, precise thermal elevations occurring throughout bone during surgical cutting are not well defined. It is also unclear whether temperatures generated in osteocytes in vivo are sufficient to induce cellular responses. Experimental analysis of temperature generation throughout bone is challenging due to its complex heterogeneous composition. There is a specific need for advanced 3D computational models that incorporate multi-scale variability in both bone tissue composition and thermal properties to predict how organ level thermal elevations are distributed throughout bone cells and tissue during orthopaedic cutting procedures.