11 doctors weighed in:
What is the most common cause of thoracic outlet syndrome?
11 doctors weighed in

Dr. David Cooke
Surgery - Thoracic
6 doctors agree
In brief: Narrow space
The most common cause is a narrow space between the first rib and a muscle tendon from the anterior scalene muscle.
Other causes included an aberrent cervical rib.

In brief: Narrow space
The most common cause is a narrow space between the first rib and a muscle tendon from the anterior scalene muscle.
Other causes included an aberrent cervical rib.
Dr. David Cooke
Dr. David Cooke
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Dr. Laurence Badgley
General Practice
3 doctors agree
In brief: Biomechanical Injury
Speculation of abnormal soft tissue scalene muscle structure wrong.
 my clinic data proves cause is function of one cm space between bony clavicle and first rib (costoclavicular dimension), the true thoracic outlet for major arm artery and nerves; acromioclavicular joint laxity from acute injury and/or one shoulder drooped from unilateral thin/weak trapezius due to chronic head tilt (@ quora.Com).

In brief: Biomechanical Injury
Speculation of abnormal soft tissue scalene muscle structure wrong.
 my clinic data proves cause is function of one cm space between bony clavicle and first rib (costoclavicular dimension), the true thoracic outlet for major arm artery and nerves; acromioclavicular joint laxity from acute injury and/or one shoulder drooped from unilateral thin/weak trapezius due to chronic head tilt (@ quora.Com).
Dr. Laurence Badgley
Dr. Laurence Badgley
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In brief: Trauma
Many people are born with cervical ribs, elongated transverse vertebral processes, and narrow nerve tunnels in the spine and other areas of the body.
Certain injuries can add to compression where nerves pass, and symptoms can ensue. Chronic activities overhead may result in tos issues, but an acute trauma seems more common.

In brief: Trauma
Many people are born with cervical ribs, elongated transverse vertebral processes, and narrow nerve tunnels in the spine and other areas of the body.
Certain injuries can add to compression where nerves pass, and symptoms can ensue. Chronic activities overhead may result in tos issues, but an acute trauma seems more common.
Dr. Bennett Machanic
Dr. Bennett Machanic
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