Thoracic Outlet Syndrome Flashcards
What is thoracic outlet syndrome?
Signs and symptoms attributable to compression (secondary to a decrease in the thoracic outlet space or shortened muscles) or traction of the neurovascular bundle at the brachial plexus
What are 4 areas within the anatomical location of the brachial plexus that are vulnerable to injury?
- Sternocostovertebral Space
- Scalene Triangle
- Costoclavicular Space
- Subcorocoid Space
What 3 structures make up the Sternocostovertebral Space?
- Sternum anteriorly
- Spine posteriorly
- First rib (laterally)
What 3 structures make up the scalene triangle?
- Anterior scalene muscle
- Middle scalene muscle
- First rib
What 2 structures travel through the scalene triangle? What structure (1) passes over the scalene triangle?
- Brachial plexus and subclavian artery travel through this triangle
- Subclavian vein passes over the first rib anterior to the anterior scalene muscle
What 2 structures form the costoclavicular space?
- Clavicle
2. First rib
What 3 structures make up the subcorocoid space?
- Corocoid process
- Insertion of the pectoralis minor
- Ribs (posteriorly)
True or False: Thoracic Outlet Syndrome is more common in men than women.
FALSE
More common in women
Ration: 3-4:1
What are 12 possible anatomical causes of thoracic outlet syndrome?
- cervical rib
- bifid first rib
- Fractured first rib
- Fusion of the first and second ribs
- Long transverse process at the cervical spine,
- Clavicular fracture/ anomaly,
- Fibrous or ligamentous bands
- pre-fixed plexus (the brachial plexus exits the spinal canal from the C4 through C8 foramina, rather than from C5 through T1)
- post-fixed plexus (the brachial plexus exits the spinal canal from the C6 through T2 foramina, rather than from C5 through T1)
- Drooping shoulder (this is common in large breasted women)
- Upper thoracic kyphosis
- Winged scapula
What posture can lead to thoracic outlet syndrome?
Forward Head Posture
What 4 positions occur as a result of forward head posture?
- Thoracic flexion
- Increased cervical lordosis (perhaps lower cervical flexion)
- Scapular abduction
- Shoulder internal rotation
What muscles (7) become tight and what muscles (2)become elongated as a result of forward head posture?
- Tightness of the scalenes, sternocleidomastoid, suboccipitals, upper trapezius, pectorals, serratus anterior, and levator scapulae
- Elongation of the middle trapezius and lower trapezius
Muscles, in either a shortened or elongated position, are placed at a mechanical ____, resulting in ____ of other muscles and perpetuating muscle imbalance
- disadvantage
2. compensatory overuse
Typically, in these scapular-abducted positions, the ___ stabilizers become weakened, causing ___ of the scapular elevators (upper trapezius, levator scapulae, upper rhomboids).”
- lower scapular
2. overuse
List 3 muscles that may have strength impairments as a result of forward head/shoulder posture.
- Middle trapezius
- Lower trapezius
- Lower cervical paraspinal and/or anterior upper cervical musculature (longus colli and longus capitus)