What is the insertion point for the middle scalene muscle?

The middle scalene muscle inserts at the superior aspect of the first rib. This anatomical relationship is crucial because the middle scalene, along with the anterior and posterior scalene muscles, plays a significant role in the movement and stability of the cervical spine as well as assisting in rib elevation during respiration. The insertion on the superior aspect of the first rib allows for this muscle to contribute effectively to lateral flexion of the neck and to elevate the first rib, which is vital during deep inhalation.

Understanding the anatomy involved, the first rib serves as a critical landmark for various neck and upper body movements, making the insertion site essential for both functional anatomy and the study of musculature involved in respiratory mechanics.