Survey on Needle Depth and Angle at Jianzhongshu Acupoint Under Ultrasound Guidance

This study utilizes ultrasound imaging to measure the needle insertion depth at Jianzhongshu (SI15) and an electronic goniometer to assess insertion angles. The aim is to collect anatomical reference data for acupuncture needling precision, focusing on the relationship between SI15 and the insertion point of the levator scapulae muscle. This is an observational study designed to collect anatomical reference data for acupuncture needling, without evaluating therapeutic effects.