The principle of the cervical muscle lift is similar to that of the brow lift, except that it is the cervical muscle, one of the largest expression muscles in the body, that is relaxed, while retaining the lifting ability of part of the cervical muscle in the cheeks, so that this part, together with other upward lifting muscles such as the zygomaticus major and zygomaticus minor, can lift the skin of the cheeks upward, thus making the jawline more defined and the person more youthful. This results in a more defined jawline and a more youthful appearance. When we were young, our necks were firm and well defined. With the erosion of time, the neck starts to sag and the contours become blurred. What happens to our neck tissues during this process? The skin loses elasticity, the fat under the chin accumulates and sags, the connection between the broad neck muscle and the underlying fat and adjoining muscles weakens, the muscle tone decreases, and the submandibular glands sag. These, cause changes in the contour of our neck. The tone and shape of the vastus lateralis muscle and its ability to support fatty tissue play an important role in the shape of the neck. What is the broad cervical muscle? The latissimus dorsi is a thin superficial layer of muscle located underneath the skin of the neck, beginning at the clavicle and upper chest fascia and ending at the lower facial skin, muscles and jawbone. As a descending muscle of the neck, it has a pull-down force on the skin of the neck. The young cervical latissimus muscle is firm and tense, with a continuous laminar distribution. Genetics, obesity, and age (after 20 years of age) act separately or synergistically to loosen and sag the vastus cervicis muscle, which tends to store fat and develop a double chin, unevenly distributed and concentrated toward the middle, producing a prominent vertical band of the vastus cervicis muscle. What is a broad neck muscle lift? The use of Botox to deflate the pull-down force of the latissimus dorsi muscle can lift the sagging skin underneath, making the jawline contour clearer; and can blur the band of the latissimus dorsi muscle, so that the sagging skin line of the side face can be lifted and tightened again, and the curve of the jawline can become smoother and softer, and people will become younger as a result.