The goal of this study is to identify and develop multiparametric quantitative ultrasound imaging (QUI) biomarkers for assessing upper trapezius muscle with and without chronic neck pain and their response to treatment. This goal will be achieved by testing the underlying hypothesis that abnormal muscle tissue can be identified based on its physio-mechanical properties, and that changes in these properties can be used to guide and monitor treatment progress. Preliminary results have shown that biomarkers including muscle B-mode ultrasound echo-intensity, shear wave velocity, and longitudinal strain ratios associated with muscle tissue structure, mechanics, and function significantly differ between muscles in low back pain and neuromuscular disorders and normal muscles. This study will determine which biomarkers are best suited to differentiate abnormal muscle in chronic neck pain from healthy muscles and develop a quantitative objective program for chronic neck pain management.

The main objective will be achieved through two aims:

Aim 1: Identify and develop quantitative biomarkers to distinguish structure, mechanics, function, and blood flow in abnormal muscles associated with chronic neck pain from normal muscles, correlated with clinical osteopathic assessments.

To determine the diagnostic performances of echo-intensity as a muscle structural biomarker, shear wave velocity and longitudinal strain ratio as muscle mechanics/function biomarkers, and color Doppler microvascular index as a muscle blood flow biomarker will be evaluated. These assessments will be evaluated in healthy subjects to test these quantitative biomarkers on upper trapezius muscle in the neck region to establish normal control values. To determine the clinical utility of these novel biomarkers, subjects with chronic neck pain will receive clinical osteopathic assessments over the neck region using conventional osteopathic examination with qualitative disease scoring by clinicians and subjective pain scales by subjects. The above quantitative biomarkers and qualitative osteopathic assessments of corresponding tissues with and without chronic neck pain will be analyzed using advanced ultrasound processing methods and statistical analyses.

Aim 2: Evaluate the abilities of quantitative biomarkers developed in Aim 1 to assess the responses of muscle tissue structure, mechanics, function, and blood flow to osteopathic manipulative treatment (OMT) for chronic neck pain.

To determine the prognostic performance of the QUI biomarkers developed in Aim 1 in predicting clinical response to OMT treatment, it will demonstrate that abnormal muscle tissue physio-mechanical properties to be directly linked to the pain of the patients. This trial will determine if improvement in abnormal biomarker values leads to improvement in subject's pain and osteopathic assessments. Subjects with chronic neck pain will be examined at intervals with biomarker measurements and osteopathic assessments. Image processing and statistical analysis will be used to determine the performance of the biomarkers in predicting response to treatment. the approach used in this study is supported by preliminary studies, which show how ultrasound biomarkers change following OMT, returning toward more normal muscle tissue mechanics.

This clinical trial will validate at least one clinically useful prognostic biomarker for chronic neck pain management, lay the foundation for further clinical research and treatment based on quantitative, reproducible, well-established methods, and lead to a large grant application.

Inclusion Criteria:

Inclusion criteria for the healthy participants include:

• Age 18 years and older;
• Healthy. No history of musculoskeletal conditions, such as severe pain, trauma, joint or spine surgery;
• Able to sign written informed consent,
• Tolerant to the osteopathic exam, and ultrasound.

Inclusion criteria for patients with chronic neck pain include:

• Age 18 years and older
• Having chronic neck pain persisting longer than 12 weeks, meeting TART criteria, diagnosed by an osteopathic physician;
• Able to sign written informed consent;
• Tolerant to the osteopathic exam, ultrasound, and OMT.

Exclusion Criteria:

Exclusion criteria for the healthy participants include:

• Under 18 years of age;
• Having a medical history of musculoskeletal conditions, joint and/or spine surgery, trauma;
• Employee of the study investigators;
• Being unable to competently consent or assent to participation (e.g., mentally disabled, demented, delusional, or a prisoner);
• Not tolerant to the osteopathic exam, ultrasound.

Exclusion criteria for patients with chronic neck pain include:

• Age < 18 years,
• Unable or unqualified to sign an informed consent,
• Unstable and/or late stage diseases,
• Not tolerant to the osteopathic exam, ultrasound, OMT.

There is no specific racial/ethnic background limitation in this study.

De-identified data will be available with reasonable request to principal investigator.