Design and implementation of a paradigm-specific cervical manipulation simulator with objective force-angle feedback

Cervical manipulation is a skill-intensive manual therapy procedure requiring precise control of traction force and angular displacement. Current physiotherapy training relies largely on peer-to-peer practice and subjective feedback, limiting quantitative assessment. This study describes the design and implementation of a paradigm-specific cervical manipulation simulator based on the Cyriax manual therapy concept. The proof-of-concept prototype was constructed from commercially available components with an estimated bill of materials cost of USD 820. An S-type load cell, analogue rotary encoder and USB data-acquisition system recorded traction force and angular position. Three C# software modules provided real-time acquisition, event-based post hoc visualisation and user-selected interval analysis. Angular velocity and acceleration were derived from the angle-time signal, and force-rate variables from the force-time signal; these derived variables were not independently validated against an external reference system. Traction force calibration was performed using verified reference loads, and custom software outputs were compared with the manufacturer's reference software under identical conditions. Across three calibration cycles, the pooled model was F(N) = 240.740 V - 36.373 (R² = 0.9894; SEE = 13.261 N), with maximum hysteresis of 4.83% of full-scale output and empirical expanded measurement uncertainty of ±11.161 N (k = 2). The platform recorded and visualised force-time and angle-time profiles and illustrative instructor-selected deviations. These results demonstrate technical feasibility and measurement capability but do not establish validity, reliability or educational effectiveness. Future studies should assess content and construct validity, test-retest reliability, expert-novice discrimination and transfer of learning.