Motion palpation findings and self-reported low back pain in a population-based study sample

Background: Although the clinical usefulness of motion palpation has not been established, it is one of the most commonly used diagnostic methods by chiropractors. Notably, its sensitivity, specificity, and validity in general have not been adequately studied, and most study samples have consisted of student volunteers. Objective: To determine the prevalence of positive motion-palpation findings (so-called fixations and spontaneous pain response) in relation to self-reported low back pain status and to determine the sensitivity and specificity of the motion-palpation technique carried out on the sacroiliac and lumbar joints. Design: Study subjects were examined by 1 examiner (out of 7 possible), who was unaware of their low back pain status. Information on low back pain was then collected in a self-report questionnaire. Setting: Research laboratory at the Odense University Hospital, Denmark. Participants: One hundred eighty-four twins, consisting of a subset of healthy twins taken from a panel of population-generated twins aged 19 to 42 years, made up the study sample. Examiners consisted of 7 biomechanics (chiropractic) students from the University of Southern Denmark who were proficient in motion palpation. Main Outcome Measures: The prevalence rates of motion palpation-determined fixations and of spontaneous pain reactions in response to motion palpation were studied in relation to anatomic area, self-reported low back pain status, and each other. Results: The point period prevalence of low back pain was 14%. Fixations were found in 43% of the study sample, and 25% appeared to have a painful reaction to motion palpation. There was no logical pattern of fixations and spontaneous pain reactions in relation to the low back pain status. The sensitivity was generally low (always below 60%) for fixations and pain, whereas the specificity was higher, significantly so for pain in the mid lumbar area. There was no strong association between fixations and the examiners' interpretation of a spontaneous pain reaction in response to motion palpation. Conclusion: Motion palpation does not appear to be a good method to differentiate persons with or without low back pain. It is possible to dissociate the findings of fixations and those of pain reactions.