The trapezius is a muscle that starts at the base of your neck, goes across your shoulders and extends to the middle of your back. The trapezius (traps muscle) helps you move your head, neck, arms, shoulders and torso. It also stabilizes your spine and helps with posture. Muscle strains can affect the traps and cause pain and decreased mobility.
The trapezius is a large muscle in your back. It starts at the base of your neck and extends across your shoulders and down to the middle of your back. Providers call it the trapezius because of its shape. It looks like a trapezoid (a shape with four sides, two that are parallel). Some people call the trapezius the traps muscle.
The trapezius is responsible for posture and movement. It allows you to tilt your head up and down and turn your head all around. It also helps you stand up straight, twist your torso and shrug your shoulders or pull them back. The trapezius controls your scapula (shoulder blade) when you lift your arm or throw a ball.
Trapezius muscle strain is a common injury that happens when you stretch the muscle too far. In severe injuries, the muscle can tear. To avoid injury and keep your traps strong, you should warm up before exercise and focus on staying healthy overall.
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This large muscle helps you move your body and have good posture. Healthcare providers divide the trapezius into three areas. Each area helps you with a specific kind of movement. Together, the three parts of the trapezius help you move your head, stand up straight, bend or twist your torso and raise your arms. The areas of the trapezius are:
Upper trapezius: This is the smallest section of the trapezius. It starts at the base of your neck and extends just across the tops of your shoulders. It helps you:
Middle trapezius: This area of the muscle sits just below the upper trapezius. It goes all across your shoulders. The middle traps is responsible for:
Lower trapezius: The lower traps starts around your shoulder blades and come down into a “V” shape in the middle of your back. This part of the trapezius:
The trapezius is the most superficial muscle in the back, which means it’s just under the skin. It extends from a point at the base of the neck and goes across both shoulders and down your back. It ends at a point in the middle of your back.
The trapezius muscles attach to several bones, including the spine, scapulae (shoulder blades), ribs and clavicle (collarbone). A cranial nerve (a nerve that originates from the brain) controls the trapezius.
The traps is a type of muscle called skeletal muscle. Its shape is similar to a kite. As part of your musculoskeletal system, this muscle provides a framework for bones and other soft tissues. Many individual fibers make up skeletal muscles. These fibers bundle together to create a striated, or striped, appearance.
Injuries that affect how the traps works include:
An injury to the trapezius can cause:
Providers can usually diagnose trapezius muscle problems during a physical examination. Depending on your symptoms, your provider may order an MRI or other imaging study to look for damage to the muscle.
If your provider suspects nerve damage, you may need an electromyogram (EMG). This test measures how the nerves and muscles work.
Depending on the location and severity of the injury, your provider may recommend:
To keep your muscles strong, you should focus on staying healthy overall. To avoid problems with your trapezius, you should:
If you have trapezius pain or back pain that doesn’t getter better in a day or two, call your provider. Get help right away if you have severe muscle weakness or difficulty moving your shoulders, lifting your arms or moving your head. These could be signs of nerve damage that can lead to paralysis of the traps muscle.
A note from Cleveland Clinic
Your trapezius muscle plays an essential role in helping you move your head, neck, arms, shoulders and torso. It also stabilizes your spine so you can stand up straight. You can keep this large muscle strong by staying active and maintaining a healthy weight. To avoid an injury, take time to warm up before you exercise. Focus on good posture. Stretch your shoulders and back regularly to keep your trapezius muscles flexible.
Last reviewed by a Cleveland Clinic medical professional on 06/03/2021.
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