Today’s muscle is a small group of muscles in the anterior neck, known as the scalenes.
Origin: Transverse processes of the 2nd-6th cervical (neck) vertebrae
Insertion: Upper surfaces of 1st & 2nd ribs
Actions: Bilaterally, elevates rib cage during inhalation. Unilaterally, laterally flexes the neck, and rotates head & neck to the opposite side
When these muscles have trigger points, pain/numbness/abnormal sensations can occur in the chest, upper back, shoulder, arms, and hand. Pain is hardly ever felt in the scalenes themselves.
The subclavian artery and the branches of the brachial plexus pass through a small gap between the anterior and middle scalenes. When the scalenes are tight, they can keep the 1st rib against the collarbone, which can squeeze the blood vessels and nerves. This is known as neurovascular entrapment, which can cause pain, swelling, numbness, tingling, and burning in the arm and hand. These symptoms together are known as thoracic outlet syndrome, which is often misdiagnosed as carpal tunnel syndrome.
Breathing shallowly from the chest rather than from the diaphragm severely tires the scalenes. Breathing problems and excessive coughing can cause trouble as well. Whiplash is another major cause of scalene trigger points. Because the scalenes help support the weight of the head, being aware of your posture can go a long way to prevent strain. Be careful of slouching and watch how you hold your head and neck while using your smart phones and tablets.
When I first met my husband, he was troubled by a lot of shoulder pain, especially in the front. After some massage that included work in the anterior neck, he noticed a drastic reduction in his shoulder pain. I taught him how to locate his scalenes and how he could work on them himself, and now he rarely has that pain anymore.
If any of the above sounds familiar to your own symptoms, make sure you give massage a try before you give up hope!
Davies, C. (2004). The Trigger Point Therapy Workbook (2nd ed.). Oakland, CA: New Harbinger Publications, Inc