## 2 Materials and Methods
The PMHS was positioned on a rigid seat in a \"natural\" upright seated position (\(\sim\)25\({}^{\circ}\) recline posterior torso angle). The PMHS torso was firmly secured to the seat back to prevent upper body motion, which facilitated independent motion of the head/neck complex during manual manipulation. Pressure sensors were zeroed with the specimen in the \"neutral\" position (i.e., Frankfurt horizontal plane) at test onset. Head/neck motions were manually performed by a licenced physiotherapist based on approximate normal ranges of motion (ROMs) for the joints of the human craniocerical region. For each of the head/neck motions, the physiotherapist moved the PMHS head and neck from the \"neutral\" position to the maximum motion range and then back to the \"neutral\" position, at a predefined quasistatic speed. Care was taken not to exceed physiological/anatomical maximums and to limit motion in other planes. The clinically \"safe\" maximums of each \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**PMHS \#** & \begin{tabular}{c} **MOBIOS** \\ **Donor ID** \\ \end{tabular} & **Sex** & \
\begin{tabular}{c} **Age** \\ **[yr]** \\ \end{tabular} & **[cm]** &
\begin{tabular}{c} **Status** \\ **[kg]** \\ \end{tabular} & **Cause of Death** \\ \hline
1 & 0028M & Male & 65 & 153.5 & 53.2 &
\begin{tabular}{c} Metastatic Lung \\ Cancer \\ Leukemia \\ \end{tabular} \\
2 & 0027F & Female & 53 & 155.0 & 49.8 &
\begin{tabular}{c} **PMHS 2** \\ \end{tabular} \\ \hline \hline \multicolumn{5}{c}{**Head/neck Anthropometry [cm]**} & \multicolumn{3}{c}{**PMHS 1**} & **PMHS 2** \\ \hline \hline \multicolumn{5}{c}{Head Circumference} & \multicolumn{3}{c}{55.6} & 55.5 \\ \multicolumn{5}{c}{Head Length} & \multicolumn{3}{c}{18.2} & 18.5 \\ \multicolumn{5}{c}{Head Breadth} & \multicolumn{3}{c}{14.5} & 14.5 \\ \multicolumn{5}{c}{Head Height} & \multicolumn{3}{c}{22.5} & 23.5 \\ \multicolumn{5}{c}{Neck Circumference} & \multicolumn{3}{c}{36.0} & 33.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 1: PMHS demographics and head/neck anthropometry. motion were implemented to avoid atrogenic injury and/or interaction issues between the head and the installed instrumentation. Kinematic and pressure data were coordinated and acquired at a sample rate of 100 Hz and 10,000 Hz, respectively. A computer-based nine-channel digital data acquisition system (DTS Slice Micro with DTS DataPRO software version 4.0.752, USA) recorded data from the accelerometer and pressure sensors, and a 3D motion capture system (Vicon Motion System, UK) recorded kinematics. Data analysis was performed in MatLab (MATLAB Version: 9.14.0 (R2023A)). Figure 1: (**a**) Minimally invasive surgical technique for IVD pressure sensor insertion (**b**) and exemplar miniature pressure sensor location (sensor denoted by arrow) in the C5/C6 IVD for PMHS 1 (P = posterior, R = right, L = left). Figure 2: Experimental PMHS cervical spine instrumentation utilizing whole-body PMHS with 3D motion tracking arrays and miniature pressure sensor instrumentation. Figure 4: Experimental data showing **(a)** cervical IVD pressure readings are successfully obtained for all three cervical IVD levels [C3/C4, C5/C6, and C7/T1] for PMHS 2 during motion trial 2 with **(b)** successful repeatability at each disc level between the three motion trials [e.g., C7/T1 disc level repeatability for PMHS 2]. Figure 5: Average absolute value IVD pressure readings for each cervical disc level for each motion.