Thoracic outlet syndrome cannot be described as one condition but is the agreed name for a variety of symptoms which are explained by being assumed to be due to compression of the blood vessels and nerves as they go through the area called the thoracic outlet. The outlet is made up of a triangle the boundaries of which are the scalene muscles, the first rib and the collar bone or clavicle, through which the nerves and vessels go to get to the axilla and then to the arm. Patient diagnosis is very difficult in this field and little agreement exists about the condition.
The wide variation in signs and symptoms of sufferers with thoracic outlet syndrome and the absence of any test to confirm or deny its presence means that correct diagnoses of patients with thoracic outlet syndrome is difficult. The numbers of people who suffer from this syndrome is as a consequence not clear although it is known that higher numbers of women occur in this group, especially if they have poor muscle tone and posture.
The nerves and blood vessels travel in what is termed a bundle, moving down from the cervical spine and towards the arm, going through three, mostly triangular spaces, on the way. Compression of the bundle can occur in any of the three triangles, which are already small when the arm is by the side, reducing further in size as the arm moves into certain postures. Postures which increase the tightness of the spaces are used as diagnostic tests to figure out which structures are causing the compression and which are being compressed. Doctors and physiotherapists test by placing the limb of the patient in a specific posture known to be stressful and asking them to perform a repeated muscle action such as fist clenching. This heightens the demand on the blood supply or neurological control required.
The repetitive movement of the shoulder towards the ends of its ranges makes the onset of thoracic outlet syndrome more likely, increasingly so if shoulder abduction (moving the arm out to the side) and outward rotation are involved at end ranges. A common occurrence is for swimmers to complain of pain during their stroke and this should raise the suspicion of thoracic outlet problems. Repetitive shoulder movements towards the end of the available movement make this more likely to occur in many sports or activities. Symptoms may present as neurological difficulties or as problems connected with blood supply to the arm.
Thoracic outlet syndrome presents differently due to whether the compressed structures are the blood vessels, the nerves or both together. The level of pain and disability involved can vary from mild to severe, with symptoms continuous or intermittent. The normal presentation groups are one whose symptoms are not clear or specific, the vascular group and the neurological group. Compression of the main vein or artery in the arm does not occur commonly and perhaps most often in young athletes who perform excessive overhead throwing.
If the arterial flow is disrupted the arm can change colour, there can be pain on muscle use due to their not getting enough blood and an overall pain in the hand and the arm. Mild onset is typical as blood can often get round a blockage, but when the block is large patients attend for medical review independently. Thoracic outlet syndrome from neurological compression involves compression of some of the brachial plexus, a nerve crossroads in the neck which supplies the arms. Nerve compression does not usually occur alone but presents with awkwardness holding a ball or a racket and loss of muscle bulk in the small hand muscles.
Neurological compromise may also cause pins and needles or loss of feeling, with some reports of pain but this tends not to be a major issue. Overhead actions with the arm repetitively tend again to be the aggravating factors. The third group is the contentious one, with a large number of patients who complain of pain in the neck, shoulder blade and arm. Often starting after an accident of some type, this kind of pain is not well understood and there is little medical agreement as to whether this is thoracic outlet syndrome or not.
The wide variation in signs and symptoms of sufferers with thoracic outlet syndrome and the absence of any test to confirm or deny its presence means that correct diagnoses of patients with thoracic outlet syndrome is difficult. The numbers of people who suffer from this syndrome is as a consequence not clear although it is known that higher numbers of women occur in this group, especially if they have poor muscle tone and posture.
The nerves and blood vessels travel in what is termed a bundle, moving down from the cervical spine and towards the arm, going through three, mostly triangular spaces, on the way. Compression of the bundle can occur in any of the three triangles, which are already small when the arm is by the side, reducing further in size as the arm moves into certain postures. Postures which increase the tightness of the spaces are used as diagnostic tests to figure out which structures are causing the compression and which are being compressed. Doctors and physiotherapists test by placing the limb of the patient in a specific posture known to be stressful and asking them to perform a repeated muscle action such as fist clenching. This heightens the demand on the blood supply or neurological control required.
The repetitive movement of the shoulder towards the ends of its ranges makes the onset of thoracic outlet syndrome more likely, increasingly so if shoulder abduction (moving the arm out to the side) and outward rotation are involved at end ranges. A common occurrence is for swimmers to complain of pain during their stroke and this should raise the suspicion of thoracic outlet problems. Repetitive shoulder movements towards the end of the available movement make this more likely to occur in many sports or activities. Symptoms may present as neurological difficulties or as problems connected with blood supply to the arm.
Thoracic outlet syndrome presents differently due to whether the compressed structures are the blood vessels, the nerves or both together. The level of pain and disability involved can vary from mild to severe, with symptoms continuous or intermittent. The normal presentation groups are one whose symptoms are not clear or specific, the vascular group and the neurological group. Compression of the main vein or artery in the arm does not occur commonly and perhaps most often in young athletes who perform excessive overhead throwing.
If the arterial flow is disrupted the arm can change colour, there can be pain on muscle use due to their not getting enough blood and an overall pain in the hand and the arm. Mild onset is typical as blood can often get round a blockage, but when the block is large patients attend for medical review independently. Thoracic outlet syndrome from neurological compression involves compression of some of the brachial plexus, a nerve crossroads in the neck which supplies the arms. Nerve compression does not usually occur alone but presents with awkwardness holding a ball or a racket and loss of muscle bulk in the small hand muscles.
Neurological compromise may also cause pins and needles or loss of feeling, with some reports of pain but this tends not to be a major issue. Overhead actions with the arm repetitively tend again to be the aggravating factors. The third group is the contentious one, with a large number of patients who complain of pain in the neck, shoulder blade and arm. Often starting after an accident of some type, this kind of pain is not well understood and there is little medical agreement as to whether this is thoracic outlet syndrome or not.
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