Scalenus syndrome is the 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 become enlarged and put pressure on a bundle of nerves called the brachial plexus or subclavian artery. Diagnosing this condition can be tricky, and is a subject of some controversy in the medical community. Treatment options are available for patients with nerve pain, stiffness, and other symptoms caused by scalene 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 several subtypes based on which injuries and anatomical structures are involved. In the case of scalene syndrome, the scalene muscles are to blame. Muscle enlargement may be palpable on exam and may also be visible on medical imaging studies. The images may also reveal signs of compression.
Symptoms can occur in athletes and others who perform repetitive movements that involve raising their arms. Supermarket inspectors, for example, can develop enlarged neck muscles because they repeatedly raise their arms to slide products through the checkpoint. Other forms of thoracic outlet syndrome may be associated with neck injuries, such as whiplash from car accidents, or from not using ergonomic posture in the workplace. Patients who sit or stand awkwardly can begin to develop irregular muscle growth, pain, and soreness, which can eventually lead to chronic health problems.
Patients with scalene syndrome may develop symptoms such as pain and numbness in the arm, along with tingling sensations. Weakness can also occur as the brachial plexus controls several key muscles and damaged nerves may not control the arm properly. Pain and soreness in the neck and shoulder can also occur. If the patient's subclavian artery is involved, symptoms such as irregular pulse may be seen.
A doctor may examine a patient with these symptoms to learn more about the patient's condition and determine if scalene syndrome may be responsible. One diagnostic option is to check for Adson's sign, a loss of the radial pulse in the arm when the patient breathes with the arm outstretched and the head turned in the same direction. Some people experience this clinical sign without the presence of scalene syndrome, so it is important that the patient obtain a thorough evaluation. This may include imaging and an exam.
Treatment options may start conservatively with some stretching and physical therapy. Some patients benefit from medication and ergonomic positioning training to prevent further injury. Surgery may be an option in extreme cases that do not respond to other treatment.