Scalene Syndrome

By | June 10, 2022

Scalene syndrome is a nerve compression syndrome that belongs to the thoracic outlet syndromes. In the syndrome, the brachial plexus becomes trapped in the skeletal gap between the anterior and medius scalene muscles. In the case of neurological deficits, the compressed nerve is surgically freed.

What is scalene syndrome?

The so-called bottleneck syndromes are a group of compression syndromes. Compression syndromes are understood by medicine to be illnesses that can be traced back to the jamming of an anatomical structure in a specific bottleneck in the body. For what does ichthyosis vulgaris mean, please visit

The scalene syndrome is a nerve compression syndrome in which the brachial plexus of the arm gets stuck in the so-called scalene gap. The anterior scalene muscle is a muscle between the cervical vertebrae and the ribs, which under certain circumstances can constrict the course of the arm nerves. The scalenus syndrome is also called neck rib syndrome or Naffziger syndrome.

The clinical picture is now summarized under the more comprehensive term thoracic outlet syndrome. These syndromes are upper thoracic neurovascular compression syndromes. Other nerve compression syndromes from this group of diseases are hyperabduction syndrome, pectoralis minor syndrome, Paget von Schroetter syndrome and costoclavicular syndrome. The exact prevalence of scalene syndrome is not known. Overall, however, thoracic outlet syndromes are considered to be relatively common.


The cause of scalene syndrome is compression of the brachial plexus. This nerve plexus of the arm runs along the arms, shoulders and chest. The anterior scalene muscle runs between the cervical vertebrae and the ribs. The area between the anterior scalene muscle and the medius scalneus muscle is also known as the scalene gap.

This point is a bottleneck for the brachial plexus, especially if the patient has an additional cervical rib. Extra cervical ribs are considered one of the most common causes of scalene syndrome. However, the cause of the syndrome does not necessarily have to be a superfluous bony element, but can also be related to the muscle itself. The muscle can be affected by muscle hypertrophy, for example.

The resulting oversize of the muscle tissue can also squeeze the arm nerve plexus. Another cause is a steep stance or exostosis of the upper ribs, which can result in a severely narrowed scalene gap. In the latter case, in addition to the cords of the brachial plexus, cords of the subclavian artery are also affected by compression. Under certain circumstances, compression can also be associated with overly developed ligaments.

Symptoms, Ailments & Signs

The brachial plexus provides motor innervation to the shoulder and chest muscles and is also involved in the motor and sensory innervation of the arm and hand. For this reason, patients with scalenus syndrome typically suffer from stress-dependent neuralgiform pain in the shoulder and arm area, which manifests itself primarily in the ulnar forearm area.

Since the sensory innervation of the hand is disturbed due to the nerve compression, hypoesthesia or paresthesia occurs in the hand area. In some cases, these sensory disturbances are associated with intermittent circulatory disturbances, especially with simultaneous compression of the subclavian artery. The affected arm falls asleep more and more frequently due to these circulatory disorders.

Sometimes there is a numbness and a feeling of heaviness. In the later stages of a scalenus syndrome, the patient may complain of paralysis of the arm and chest muscles, since the muscles in this area are motor-innervated by the compressed brachial plexus. From a certain stage, paralysis-related increasing atrophy of the muscles, especially the small hand muscles, is also conceivable.

Due to a narrowing of the subclavian artery, the smallest blood clots also appear in the advanced stage of the syndrome, which under certain circumstances can occlude the finger vessels and thus lead to discoloration of the fingers.

Diagnosis & course of disease

The diagnosis of a scalene syndrome is usually made by the doctor using a provocation test. Chest imaging may also be required as a diagnostic tool. In the differential diagnosis, the physician must differentiate the syndrome from other thoracic outlet syndromes. The prognosis for patients with scalene syndrome is generally favorable.


Patients with scalene syndrome typically suffer from exercise-related pain in the shoulder and arm area. These are usually associated with sensory disturbances and circulatory disorders, which can lead, for example, to restricted movement and, rarely, to the formation of blood clots. In the later stages of the disease, muscle atrophy can also occur.

The small hand muscles are particularly affected, which are less efficient due to the tissue atrophy and significantly restrict the affected person in their daily tasks. As the disease progresses, neurological deficits such as paralysis and movement disorders occasionally appear. If left untreated, this can result in permanent damage to the compressed nerve plexus. In addition, thrombosis occurs, which occludes the finger vessels and leads to discoloration of the fingers.

In pain therapy, the individual drugs can cause side effects and, under certain circumstances, major complications. If local anesthetics are injected, the surrounding tissue can theoretically be poisoned. This is associated with nervousness, dizziness and seizures. In rare cases, a drop in blood pressure and cardiac arrhythmias can also become noticeable. A surgical procedure involves the usual risks: infections, bleeding, nerve injuries and impaired wound healing.

When should you go to the doctor?

Scalenus syndrome always requires medical treatment. In most cases, there can be significant limitations and problems in everyday life. The scalene syndrome does not heal on its own. For this reason, a doctor who can alleviate these symptoms should be consulted at the first sign. A doctor should be consulted if the person concerned suffers from severe pain in the arms or shoulders. This pain usually occurs without any particular reason and has a very negative effect on the movement and also on the quality of life of the person concerned.

In many cases, circulatory disorders or sensory disturbances also indicate scalene syndrome and should also be examined by a doctor. Numbness can also indicate scalene syndrome. You should also see a doctor if blood clots form. The scalene syndrome can be recognized and treated by a general practitioner or an orthopedist.

Treatment & Therapy

In the case of scalene syndromes of milder severity, no further therapy is often necessary. In this case, the treatment focuses primarily on alleviating the pain symptoms. Such an alleviation can be achieved by conservative medication of the patient. In most cases, however, the most important thing is to avoid the stresses that cause pain. The patient does not have to be treated unnecessarily with painkillers.

In the case of pronounced pain symptoms, the pain is usually reduced by means of pain therapy. As such, for example, the local infiltration of the affected muscle with a local anesthetic comes into question. This therapeutic local anesthesia can also be carried out with the help of an implant that regularly releases local anesthetic into the muscle.

If there are symptoms in addition to the pain symptoms, pain therapy is not sufficient to treat the scalene syndrome. This is especially true when neurological deficits such as paralysis set in. Surgical intervention may be indicated to restore the patient’s mobility. The intervention should be carried out before permanent damage occurs to the compressed nerve plexus.

With surgical intervention, the primary cause of the compression is addressed. This therapeutic step often corresponds, for example, to the surgical removal of an additional cervical rib.


Strictly speaking, the scalene syndrome cannot be prevented, since the syndrome is sometimes caused most frequently by supernumerary cervical ribs. Such supernumerary cervical ribs are innate and cannot be avoided by active steps. However, the pain symptoms of the syndrome can be prevented insofar as pain-generating stress is avoided.


In most cases, the possibilities and measures of aftercare for scalene syndrome are significantly limited. In any case, the patient is dependent on a quick and, above all, early diagnosis and treatment of this disease, so that there are no complications or other symptoms in the further course. The sooner a doctor is consulted about scalenus syndrome, the better the further course of this disease is usually.

Most of those affected are dependent on physiotherapy and physiotherapy measures for scalenus syndrome. Some of the exercises from these therapies can also be repeated at home, speeding up healing. In many cases, it is also necessary to take various medications to alleviate the symptoms.

The person concerned should always pay attention to the prescribed dosage and regular intake. If there is a desire to have children, a genetic examination and counseling can also be carried out. This can prevent the recurrence of this disease. Further aftercare measures are usually not available to the person concerned.

You can do that yourself

In day-to-day activities, care must be taken to ensure that there are no situations of physical exertion. The body should be protected from overuse. To support the muscular system, it is advisable to use massages or regular warm baths. If there are limitations in mobility, physiotherapeutic treatments are carried out. The person concerned can also carry out independently learned exercises and training units to improve their own health outside of the fixed therapy times.

Since thrombosis can develop, circulatory disorders must be prevented at an early stage. Rigid postures should therefore never be adopted. If the skin develops sensory disturbances or tingling on the skin, compensatory movements must be carried out immediately. Overall, sufficient exercise helps to strengthen the immune system and stimulate blood circulation.

Characteristic of the scalene syndrome is an intense development of pain. Although these complaints are treated with medication, it has been shown in many patients that a strengthening of the mental area can lead to a reduction in pain perception. It is therefore advisable to try out methods such as mental training, yoga or autogenic training. The techniques of the described relaxation procedures can also be integrated independently and responsibly at any time in everyday life by the person concerned. In addition, cognitive patterns are optimized, making it easier to deal with the disease.

Scalene Syndrome