Where does the middle scalene muscle insert?

The middle scalene muscle inserts on the first rib, specifically positioned behind the anterior scalene muscle. This anatomical relationship is crucial as it contributes to the function of the scalene muscles during respiration and neck movements. The middle scalene elevates the first rib, which assists in deep inhalation by expanding the thoracic cavity. Its location and attachment point are important for the mechanical advantage it provides during these actions. Understanding this component of the scalene muscles highlights their role in both breathing mechanics and the overall movement of the cervical spine.