From mannequins to humans – are manual therapy motor skills transferable? A mixed-methods study

Manual therapy, including spinal manipulative therapy (SMT), is a core component of chiropractic education. Simulation tools such as the Human Analogue Mannequin (HAM ® ) have been developed and coupled with force-sensing technology to support safe and structured training of SMT force-time characteristics. However, it remains unclear whether motor skills acquired using these tools are transferable to real-world scenarios. This sequential explanatory mixed-methods observational study investigated whether chiropractic students, proficient at applying a set of pre-specified SMT force-time characteristics to the HAM ® , could replicate those same characteristics in humans. Quantitative data measured SMT force-time characteristics (preload force, peak impulse force, time to peak impulse force) applied on the HAM ® . Participants meeting the predefined force-time criteria in 4 out of 5 trials proceeded to apply SMTs to a human. Qualitative data from a survey with open-ended questions explored participants’ perceptions of their ability to replicate the SMT and differences between the HAM ® and humans. Ninety-five students participated (56% female, median age: 25 years), and 50 (53%) met the criteria on the HAM ® . Thirty-seven (74%) of the participants who met the criteria on the HAM ® also met the criteria on humans. No significant differences in participant characteristics were found between those who met or did not meet the criteria when applying SMT on humans. Participants who did not meet SMT force-time criteria on either the HAM ® or humans often under-applied preload force. Time to peak impulse force criteria was usually met across all trials. Qualitatively, participants perceived that internal factors (e.g., previous experience, emotions, tactile feel) and differences between the HAM ® and humans (e.g., stiffness, breathing) influenced their ability to replicate the SMT force-time criteria on humans. Most students who successfully applied SMT force-time characteristics on a mannequin were able to replicate them on humans. Not meeting the SMT proficiency criteria (particularly in preload force) and the influence of non-biomechanical factors highlights the complexity of manual therapy motor skill development.