The platysma is a broad, thin sheet of muscle that spans the front of your neck, stretching from your chest and shoulder area up to your jawline and lower face. Unlike most muscles that connect bone to bone, the platysma sits just beneath the skin and attaches directly into the tissue of your neck and face. It’s one of the muscles responsible for facial expression, and it plays a visible role in how your neck ages over time.
Where the Platysma Sits and What It Connects
The platysma covers nearly the entire front and side of the neck like a wide, flat curtain. It originates from the skin and connective tissue over the upper chest and shoulder, then fans upward across the collarbone and neck. At the top, its fibers blend into the skin and muscles of the lower face, reaching the jawline, the corners of the mouth, and the lower lip. The two halves of the muscle (left and right) don’t always meet perfectly in the midline of the neck. In many people, there’s a gap between the inner edges, which becomes more noticeable with age.
The muscle gets its nerve supply from the cervical branch of the facial nerve, the same nerve network that controls all the muscles of facial expression. Its blood supply comes primarily from the submental artery, which runs beneath the chin, with secondary contributions from the superior thyroid, occipital, and posterior auricular arteries.
From an evolutionary standpoint, the platysma is thought to be a remnant of a much larger muscle sheet called the panniculus carnosus, which allows many mammals to twitch their skin to shake off insects or water. In humans, this muscle layer has mostly disappeared, but the platysma persists in the neck.
What the Platysma Does
The platysma is a muscle of expression more than a muscle of power. When it contracts, it tenses the skin of the neck, creating visible vertical ridges. It can pull the corners of the mouth and the lower lip slightly downward, and it assists with opening the jaw by pulling the mandible down. The overall effect makes the neck appear shorter and wider while lowering the midface tissues, including the lower eyelids and cheeks. This deepens the creases that run from the nose to the corners of the mouth.
If you’ve ever seen someone grimace in horror, surprise, or disgust, you’ve seen the platysma at work. That taut, cord-like look in the neck during extreme expressions is the muscle firing visibly beneath the skin. That said, its role in moving the lower lip is relatively minor. The heavy lifting for lip depression is handled by two other muscles: the depressor anguli oris and the depressor labii inferioris.
Platysmal Bands and Aging
The most common reason people hear about the platysma is in the context of aging. “Platysmal bands” are those vertical cords or ridges that become increasingly visible on the front of the neck as you get older. For a long time, the prevailing theory was that these bands form because the skin sags and the muscle loses tone. But research has challenged that idea. A study published in Plastic and Reconstructive Surgery found that platysmal bands are actually caused by ongoing muscle activity, not relaxation. The skin follows the muscle rather than the other way around.
This distinction matters because it shapes how the bands are treated. If the problem were simply loose skin, tightening the skin alone might fix it. But because the muscle itself is driving the banding, effective treatments need to address the platysma directly.
Cosmetic Treatments for the Platysma
For people bothered by platysmal bands, two main approaches exist: injectable treatments and surgery.
Botulinum toxin injections (commonly known as Botox) can temporarily relax the platysma and soften the appearance of bands. A typical protocol involves injecting small doses along each visible band, with roughly 5 injection points spaced about 2 centimeters apart per band. A total of around 40 units is often used across both sides of the neck to treat the medial and lateral bands. The effect is temporary, generally lasting a few months before the muscle activity returns.
For more lasting results, surgical options fall under the umbrella of platysmaplasty, often performed as part of a neck lift or facelift. The most common technique involves bringing the inner edges of the left and right platysma together in the midline of the neck, trimming any excess muscle, and suturing the edges smoothly together. Variations include:
- Corset platysmaplasty: a continuous suture runs up and down the midline, cinching the muscle like a corset for a tighter contour.
- Hammock platysmaplasty: the muscle edges are overlapped in a double-breasted fashion across the middle of the neck.
- Lateral platysmapexy: the platysma is sutured to the fascia of the large neck muscle behind it to address mild horizontal looseness.
- Platysma myotomy or myectomy: the muscle is partially cut or removed to eliminate dynamic banding that persists even after tightening.
Nerve Damage and Platysma Dysfunction
Because the platysma is controlled by the facial nerve, conditions that damage this nerve can affect how the muscle works. Bell’s palsy, the most common cause of sudden facial nerve paralysis, can lead to a phenomenon called synkinesis during recovery. Synkinesis happens when nerve fibers regrow and connect to the wrong muscles, causing involuntary movements. For example, you might try to smile and your platysma contracts at the same time, creating an unwanted pulling sensation in the neck.
Platysma synkinesis is surprisingly common after facial palsy, showing up in about 65% of patients with synkinetic recovery. Among those affected, roughly 85% report subjective complaints about it. The facial movements most likely to trigger involuntary platysma contraction are snarling, open-mouth smiling, and lip puckering. Botulinum toxin injections into the platysma can help manage this by dampening the unwanted contractions without significantly affecting the muscle’s limited functional role.