1. State Key Laboratory of Tribology, Department of Precision Instrument and Mechanology, Tsinghua University, Beijing100084, China
2. Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057, China
3. Department of Biomedical Engineering, Tsinghua University, Beijing100084, China
4. Shenzhen No. 2 People's Hospital, Shenzhen 518049, China
Existing cervical disc pressure measurement methods have limited accuracy. This paper presents a method to measure the pressure without damaging the disc via indirect measurements. The interior strain condition and the tiny motion of the cervical disc are measured by placing a strain gauge on the front surface of the disc. The mechanical property of the disc can then be used to calculate the disc pressure. The tests showed that the measurement error was less than 15% and the correlation coefficient with invasive direct measurements was 0.79. The precision and repeatability of the surface strain method are better than the traditional method. So, this provides a noninvasive way to measure the disc pressure.
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