Drilling pattern analysis of femur bone based on inertial measurement unit signal

Femoral fixation surgery is usually operated in the case of hip fracture problems resulting from fall or accidental injury. Traditionally, this process involves an optical navigation system, which helps surgeons to detect the position and progress of operation. However, patients might be exposed to redundant radioactivity and the output is not processed in real-time. On the other hand, an inertial measurement unit (IMU), which has a small size and high sensitivity and is widely utilized in consumer electronics, can be used to record motion changes from its accelerometer and gyroscope, contributing to tracking and navigating in the surgery more efficiently. This paper proposed a method to detect signals generated from femur during drilling process using IMU sensor. Feature extraction methods, like continuous wavelet transform (CWT), were used to reveal the characteristics of the signals and support vector machine (SVM) was then utilized to help distinguish the different layers of the bone from the drilling process. Results indicated that IMU could enable doctors to get prompt feedback when drilling in the surgery, and help them monitor the operation procedure in the future.