What Is Scalenus Syndrome?

Scalenus syndrome is compression of structures around the neck as a result of muscle growth. This condition is associated with the scalene muscles in the neck, which can enlarge and put pressure on a bundle of nerves called the brachial plexus, or the subclavian artery. Diagnosis of this condition can be tricky, and it is a topic of some dispute in the medical community. Treatment options are available for patients with nerve pain, stiffness, and other symptoms caused by scalenus syndrome.

This condition is a form of thoracic outlet syndrome, where injuries cause problems with the brachial plexus or subclavian artery. Doctors divide this thoracic outlet syndrome into a number of subtypes on the basis of which injuries and anatomical structures are involved. In the case of scalenus syndrome, the scalene muscles are at fault. Muscle enlargement may be palpable on an examination and can also be visible in medical imaging studies. Images may reveal signs of compression as well.

The symptoms can occur in athletes and other people who engage in repetitive motion involving lifting the arms. Supermarket checkers, for example, can develop enlarged neck muscles because they repeatedly lift their arms to swipe products at the checkstand. Other forms of thoracic outlet syndrome can be associated with injuries to the neck, such as whiplash from car accidents, or with failing to use ergonomic posturing in the workplace. Patients who sit or stand awkwardly can start to develop irregular muscle growth, pain, and soreness, which may eventually lead to chronic health problems.

Patients with this syndrome can develop symptoms like pain and loss of sensitivity in the arm, along with tingling sensations. Weakness can also occur, as the brachial plexus controls a number of key muscles and the damaged nerves may fail to control the arm adequately. Pain and soreness in the neck and shoulder can happen as well. If the patient's subclavian artery is involved, symptoms like irregular pulse may be observed.

A doctor can examine a patient with these symptoms to learn more about the patient's condition and determine if scalenus syndrome may be responsible. One diagnostic option is a check for Adson's sign, a loss of the radial pulse in the arm when the patient breathes in with the arm stretched out and the head turned in the same direction. Some people experience this clinical sign without the presence of scalenus syndrome, making it important for the patient to get a thorough evaluation. This can include imaging and an exam.

Options for treatment can start conservatively with some stretches and physical therapy. Some patients benefit from medications and coaching in ergonomic positioning to prevent future injury. Surgery can be an option in extreme cases that do not respond to other treatment.