The AAO Journal, 2024/06, 34(2):32-33. doi: 10.53702/i2375-5717-34.2.16, type of study: ,ppt,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

Full text    (https://meridian.allenpress.com/aaoj/article/34/2/16/500954/LBORC-NUFA-Poster-Abstracts-2024-Students)

Keywords:

autonomic nervous system [154]
cervical spine [320]
heart rate variability [69]
MET [640]
muscle energy technique [180]
pretest posttest design [241]

Abstract:

Introduction/Background: Introduction/Background: Osteopathic manipulative treatment (OMT) benefits on autonomic nervous system (ANS) function can be quantified using heart rate variability (HRV).1 HRV measures variation in beat-to-beat intervals reflecting ANS activity.2 Low HRV is associated with stress, pain, and chronic diseases.3,4 Elevated HRV is linked with optimal health and reduced mortality.2 Objectives: To determine whether post-isometric muscle energy (MET) targeting the cervical spine at atlantooccipital joint (OA), C1, and C2, chosen for association with the vagus nerve, improves HRV variables related to vagal tone.5,6 Methods: Single group within-subject design is recommended in the literature, and selection bias mitigated through strict exclusion criteria with participants from the same general population.7-14 Exclusion criteria included self-reported heart failure, myocardial infarction, hypertension, asthma, diabetes, arrhythmias, smoking, systolic blood pressure >150mmHg or <90mmHg. Inclusion criteria included medical school students and faculty. Five-minute measurements of pre and post MET using a Firstbeat Bodyguard3 electrocardiogram sensor with thirty-three healthy participants, adequate for 80% power to detect a large effect.15 Evaluated somatic dysfunctions at OA, C1, and C2 were treated using MET by osteopathic physicians trained in Osteopathic Neuromusculoskeletal Medicine. Vagal tone-relevant HRV variables include root mean square of successive differences (RMSSD), percentage of successive normal sinus RR intervals more than 50 ms (pNN50), high frequency (HF), Parasympathetic Index (PNSI), and Sympathetic Index (SNSI).7 Repeated measures t-test analyzed mean HRV differences after OMT. Outliers were removed using 0.05 significance level. Results: Post MET on cervical spine (OA, C1, and C2) showed significant (p<0.01) increase in vagal tone related HRV variables compared to baseline. Conclusions: MET targeting OA, C1, and C2 may increase vagal tone evident by enhanced HRV. Future directions address limitations including following duration of effect.