Many people who have pain in the neck, the upper back, and the shoulders, or numbness in the arm, usually do not know that the cause may come from a small muscle called the "Scalene Muscle" in the area of the side of the neck. This group of muscles has an important role in breathing and in the movement of the neck, but when there is a problem it greatly affects daily life, particularly for office workers who have to sit in front of a computer for a long time, and for athletes who use the muscles in the area of the neck and the shoulders heavily.

What is the Scalene Muscle?

Understanding basic anatomy will help us understand the problem and the way of putting it right better. The scalene muscle is a group of deep muscles situated in the area of the side of the neck, having the character of bundles of muscle fibres connecting between the upper ribs and the cervical spine. This specific position makes the scalene muscles important in many respects.

Where in the body is the position of the scalene muscles?

If you place your hand at the side of your neck and gradually press down, you will be able to feel the scalene muscles that are in that area. These muscles begin from the cervical vertebrae, from the 3rd-7th, and extend down to attach to rib 1 and rib 2. This special position is in the area called the "Scalene Triangle", which is the area where the brachial plexus nerve and large blood vessels pass through to control the working of the arm and the hand.

How many bundles do the scalene muscles have and how are they important?

The complexity of the scalene muscles continues when we consider the structure, which is divided into 3 main bundles, each bundle having a different duty and character.

Scalene Anterior (the front) - this is the bundle at the very front, beginning from the 3rd-6th cervical vertebrae and going to attach to the first rib. It is the smallest bundle but is very important in helping breathing.
Scalene Middle (the middle) - this is the largest and strongest bundle, beginning from every cervical vertebra (C1-C7) and going to attach to the first rib. It is the bundle with the main role in breathing and in the movement of the neck.
Scalene Posterior (the back) - this is the smallest bundle and is at the very back, beginning from the 5th-7th cervical vertebrae and going to attach to rib 2. It has the duty of helping in breathing and in the movement of the neck in various directions.

The important duties of the scalene muscles

Besides their complex structure, the scalene muscles also have a wide variety of duties important to the working of the body, which can be divided into the following main duties.

Helping breathing - particularly when more air is needed, such as while exercising or when stressed. The muscles contract to lift the ribs so that the lungs can expand more.
Helping the movement of the neck - both turning left and right, tilting forwards and backwards, and rotating the neck in various directions, working together with the other muscles of the neck so that the movement is smooth.
Keeping the posture of the head - so that it is in balance when it has to bear the weight of the head, which is a heavy 4-5 kilograms, preventing the head from tilting or falling in one direction or another, which is very hard work for these small muscles.

The symptoms of pain in the scalene muscles: the warning signals that must be noticed

Knowing the preliminary symptoms will help one be able to distinguish them and find the way to treatment more quickly. The symptoms of the problem of the scalene muscles usually have a particular character that can be observed, and are usually more complex than the symptoms of ordinary muscle pain.

Pain in the neck, the upper back, and the shoulders, radiating down the arm

The symptom met most often and the main warning signal is pain beginning from the side of the neck, spreading to the upper back and the shoulders, and radiating down the arm. It has the character of a pinching or burning pain, which makes one feel uncomfortable and interferes with work. The symptoms usually become worse when moving the neck or lifting the arm up high, particularly turning the neck to the side with the problem. Sometimes the pain may become worse in the middle of the night or on waking in the morning.

Numbness or weakness in the hand and the fingers

When the tight scalene muscles compress the brachial plexus nerve that passes through to control the working of the arm and the hand, numbness will arise at the fingertips, particularly the ring finger and the little finger, which are usually affected the most. The numbness may alternate with tingling, or a feeling like an electric shock, followed by symptoms of weakness, the strength of the grip decreasing, and not holding objects firmly.

The relation to Thoracic Outlet Syndrome (TOS)

Understanding the link between the problem of the scalene muscles and Thoracic Outlet Syndrome is a very important matter. Scalene muscles with a problem can be the main cause of one kind of TOS called Scalene Anticus Syndrome, which arises from the Scalene Anterior muscle becoming tight and compressing the nerve. The symptoms will be similar to the general problem of the scalene muscles, but may be more severe and complex.

The main causes that make the scalene muscles tight and inflamed

Understanding the causes will help in preventing and treating effectively. The main causes in the digital age are as follows.

Unsuitable postures

Jutting the neck forwards and raising the shoulders while using the computer
Bending the face down to use the mobile phone, making the neck bear the weight of the head in an abnormal posture
Tilting the head to one side or the other for a long time

Injuries and accidents

Car accidents that cause the neck to be whipped (Whiplash injury)
Injuries from sport, particularly sports with collisions or violent movement
Falls or impacts to the head or the shoulder

Incorrect breathing, and stress

Shallow breathing when stressed makes the scalene muscles be used too much
Paradoxical Breathing makes the scalene muscles contract every time one breathes in
Chronic stress has a bearing on the working of the muscles

The way to check and test the symptoms of pain from the scalene muscles by yourself

Before entering formal treatment, understanding the methods of preliminary checking by yourself will help you be able to assess the situation and decide suitably. These tests are only a preliminary guide. If there are doubts, an expert physician should be consulted.

The simple Adson's Test posture

This method of testing helps assess whether the scalene muscles may be compressing a blood vessel or a nerve. Turn the head towards the side with the problem, raise the chin slightly, then breathe in deeply and hold. If the numbness or the pain in the arm becomes worse, or the pulse at the wrist becomes weaker, it may indicate that there is a problem with the scalene muscles.

Pressing to find the tender points (Trigger Points)

Use the fingers to press to find the tender points (Trigger Points) in the area of the side of the neck lightly, from below the ear down to the collarbone. If a point is found that hurts when pressed and has symptoms radiating to the upper back, the shoulder, or the arm, it may be a tender point of the scalene muscles. This test should be done carefully and without pressing too hard.

The way to treat and exercise the scalene muscles

Once the problem and the causes are understood, suitable and comprehensive treatment will help the symptoms improve effectively and lastingly. At PYONG Rehabilitation Clinic we have treatment with a wide variety of modern techniques that have been scientifically proven.

Dry Needling is a technique of Western needling in order to release the tender points in the scalene muscles precisely, helping reduce the tightness and relieve the pain rapidly, by stimulating the natural process of repair of the body.

PMS (Peripheral Magnetic Stimulation) uses electromagnetic waves in order to stimulate the working of the nerves and the muscles, helping restore the abnormal working and reduce pain at a deep level, as well as increasing the strength of the muscles.

High Power Laser Therapy sends laser light energy into the tissue as deep as 5-6 centimetres, in order to reduce inflammation, hasten the repair of the tissue, and relieve the pain effectively without giving rise to pain during the treatment.

Focused Shockwave Therapy uses focused shock waves together with 3D Dynamic Focusing in order to stimulate the restoration of the tissue and reduce chronic pain, with high precision and dynamic adjustment of the focus according to the character of the muscle.

Hydrodissection is an advanced technique using the injection of saline or a special solution under the control of ultrasound, in order to separate fibrous tissue that has stuck together and reduce the compression of the nerve, particularly in cases of Thoracic Outlet Syndrome connected with the scalene muscles.

Preliminary self-care is also an important thing, such as stretching the tendons of the neck lightly, adjusting the posture of sitting at work, stopping to rest the eyes and the neck every 30-60 minutes, and practising breathing deeply with the diaphragm in order to reduce the use of the scalene muscles.

In summary

Understanding the matter of the scalene muscles is the important key to putting right the problem of pain in the neck, the upper back, and the shoulders, and numbness in the arm and the hand, on target. Although the scalene muscle is a small muscle, it has a large role in helping breathing and the movement of the neck. The main causes come from unsuitable postures in the digital age, injury, and abnormal breathing from stress. Treatment with rehabilitation medicine can give a good and lasting outcome.

If you have pain in the neck, the upper back, or the shoulders, or numbness in the arm and the hand, it is recommended to consult the specialist physicians at PYONG Rehabilitation Clinic for correct diagnosis and treatment. You may enquire for further information at