The levator scapulae muscle is commonly involved in chronic neck and shoulder pain, with trigger points often located at its insertion on the superior angle of the scapula. Jianzhongshu (SI15) has been identified as a corresponding acupuncture point.

Ultrasound imaging enhances the accuracy and safety of acupuncture by providing real-time visualization of anatomical structures, while electronic goniometry allows precise measurement of needle insertion angles.

This study aims to investigate the depth and angles of needle insertion at SI15 using ultrasound and electronic goniometry. The findings will provide essential anatomical reference data for clinical applications, particularly in acupuncture treatment for neck and shoulder pain.

The levator scapulae muscle is one of the most common muscles involved in chronic neck and shoulder pain. Acupuncture has been widely recognized as an effective and safe treatment for neck pain, with trigger point acupuncture showing significant potential in pain management. In clinical practice, trigger points are often identified at the origin or insertion of the affected muscle. For the levator scapulae, one notable trigger point is located at its insertion point on the superior angle of the scapula. Jianzhongshu (SI15) has been identified as a potential acupuncture point corresponding to this trigger point.

This observational study aims to investigate the anatomical relationship between Jianzhongshu (SI15) and the insertion point of the levator scapulae muscle by assessing the depth and angle of needle insertion using ultrasound and electronic goniometry. The study will recruit healthy adult volunteers aged 18 years and older. Ultrasound imaging will be utilized to measure the needle insertion depth from the skin surface to the insertion point of the levator scapulae muscle. Additionally, an electronic goniometer will be used to assess two specific angles of needle insertion: the angle relative to the skin surface and the angle relative to the longitudinal axis of the body.

The primary objective of this study is to provide anatomical data on the needle insertion depth and angles when needling Jianzhongshu (SI15) toward the insertion point of the levator scapulae muscle. This data will serve as an essential reference for clinical applications, particularly in the treatment of neck and shoulder pain associated with the levator scapulae muscle and SI15.

Secondary objectives include assessing individual variations in needle depth and trajectory, as well as analyzing the influence of demographic factors such as age, gender, and BMI on these parameters.

By integrating ultrasound imaging and an electronic goniometer, this study aims to improve the accuracy and safety of acupuncture needling at SI15. The findings will contribute to a deeper understanding of acupuncture techniques and provide essential reference data for clinical practice, particularly in the management of neck and shoulder pain related to the levator scapulae muscle.

Inclusion Criteria:

• Healthy adults aged 18 and older
• Ability to understand and consent to participation

Exclusion Criteria:

• Severe chronic diseases or immunocompromised conditions
• Severe exhaustion or widespread infection
• Local infections or wounds at needling sites
• History of surgery or trauma in the target area
• Pregnant or breastfeeding individuals

Healthy adult volunteers without known musculoskeletal disorders, aged 18 and older, who are eligible for ultrasound-guided acupuncture. Participants are recruited from the community and screened for inclusion and exclusion criteria before enrollment.