A mathematical relationship between palpation forces and displacement associated with restriction

Abstract

[ACCESS RESTRICTED TO THE UNIVERSITY OF MISSOURI AT AUTHOR'S REQUEST.] A numerical model was developed based on clinical data that describes osteopathic clinician palpation forces and displacement. The model delivers an accurate (R[subscript 2] [greater than or equal to] 0.95) representation of forces and displacements. Palpation is the examination of the body by means of the hands and fingers to evaluate the condition of the body though pressure and displacement; specifically, this study focuses on the examination of the lumbar spinal region. The purpose of this work is to better understand tactile perception of clinicians who use this hands-on approach to assist in their assessment and diagnosis of the patient. Clinicians use perceived "restriction" to determine the health of the vertebra and body. Palpation forces can be modeled by using three key variables: stiffness, damping and apparent mass of the system. Using existing experimental data sets that were generated by tracking palpation techniques of multiple clinicians and human subjects, 91% of the total number of force application cycles analyzed were found to have a goodness of fit that was better than 95% when comparing the experimental data to the response of the three-parameter force/displacement model. A normalized stiffness difference (NSD) model was generated to quantify restriction conclusions perceived by clinicians. Recommendations for design specifications for a palpation training device that would operate using the model created in this work are suggested. The design of the training device is the subject of future work. Strategies to improve the model and experimental methods are proposed for future work.