10105840Experimental Analysis of Parameters Influencing Bone BurringClosedCollaborative R&DInnovate UKThere are a broad range of orthopaedic surgery operations, which involves cutting bones with mechanical tools such as drills, burrs and sawblades, as a preparation step for attaching prosthetics. Smith & Nephew (S+N) have commercialised a handheld robot-assisted burr (CORI) for orthopedic surgical procedures such as joint replacement surgery. Currently, there are more than 500 CORI robot installations worldwide equating to ~70,000 TKR robot-assisted procedures and ~25,000 burrs per year. The success of these operations is dependent upon the quality of the cutting procedure and motor skills of the surgeon. In particular, the heat generated during bone cutting, which is primarily due to shearing of the material and friction between the cutting tool and the bone, may cause thermal injury within the resection zone. This can impact on the formation of a strong bond between the implant and surrounding bone during healing increasing the of implant loosening, which ultimately requires revision surgery. The minimum threshold for osteonecrosis as a result of the accumulation of frictional heat in the resected zone is reported to be 1 minute or more at 47°C\[1\]. The rise in temperature during bone resection occurs through multiple mechanisms related to the skill of the operator, the quality of the bone and the mechanical load generated during the process of cutting. Therefore, we have attempted to quantify the temperature of the resected bone and exposure times during cutting using embedded thermocouples and thermal imaging techniques with the ultimate goal of optimising cutting conditions to prevent thermal osteonecrosis. Our studies present conflicting results that may originate from the sources of uncertainty in our measurement techniques. Embedded thermocouples require intimate contact with the bone tissue to achieve temperature conduction, and only provide data at remote discrete locations from the resected zone. Surface temperature measurement using thermal imaging cameras is also notoriously challenging given the dynamically changing environment associated with bone resection, varying emissivity of the imaged objects, reflections from competing surfaces, line-of-sight constraints, and ~2m distance required for capturing data in a surgical theatre set-up. In an attempt to reduce our measurement uncertainties, we have partnered with the National Physical Laboratory/NPL to co-develop an experimental set-up of our CORI handpiece that incorporates both visual, audible and tactile feedback. The overall goal is to create a training simulator for cutting bone allowing us to isolate and optimise the bone-machining tasks responsible for excessive heat generation that can lead to osteonecrosis. \[1\]Alam.et.al.Comput.Mater.Sci.,46(3),pp.738-743