Abstract
OBJECTIVE: Establishing objective descriptive data regarding manual muscle testing (MMT) as used in Applied Kinesiology, including "patient-started" versus "examiner- started" variations, is necessary before research pertaining to the reliability and clinical significance of this procedure is done. This study measured surface electromyography (sEMG) output from experienced MMT practitioners and their tested subjects during the performance of sequential MMT on the same muscle during 3 styles of MMT: normally-done, examiner-started and patient-started. METHODS: 21 examiners experienced in MMT and 24 subjects with varying degrees of exposure to MMT were engaged in the study. sEMG was simultaneously recorded from examiner and subject during testing of the middle deltoid muscle. The examiner first tested the middle deltoid muscle of the subject in his/her normal fashion 3 times and identified the MMT style as "examiner-started" or "patient-started." He/she was then asked to perform the other method of MMT. If the examiner said he/she did not know or did not differentiate which form of testing was initially done, he/she then performed one series each of examiner- and patient started MMT. RESULTS: Nine (approximately 43 %) of testers identified their "normally done" muscle test as examiner-started, 4 (19%) as patient-started and 8 (38%) as simultaneous or undifferentiated. In 64.5% of the MMT described as examiner started, sEMG showed that the examiner's contraction started before the patient's. In tests identified as patient started, 54% were indeed patient started. Undifferentiated tests were 45% patient-started, 45% examiner started and 10% exactly simultaneous. Near simultaneous contractions were observed in 55% of all tracings evaluated and 70% of undifferentiated tests. CONCLUSIONS: While many MMT practitioners consider that they are performing either an examiner- or patient-started muscle test, a significant number do not make this distinction routinely. The majority of testers in this study did near-simultaneous testing regardless of label. Examiner and subject start times alone, as measured by sEMG, did not clearly differentiate between theorized forms of manual muscle testing.