Innervation of Subclavius
Muscle: An Anatomical Study
Therefore the target muscles to which treatment must be directed are the pectoral muscles anteriorly (pectoralis major, pectoralis minor, and the subclavius
), and the posterior muscles of thoracic-spinal extension (erector spinae and transversospinalis), shoulder girdle retraction (rhomboids and trapezius, especially middle trapezius), and humeral medial rotation (subscapularis, teres major, latissimus dorsi, anterior deltoid, and pectoralis major).
Intraoperatively, it was also noticed that the space between the first rib and the clavicle was extremely narrow and hypertrophied subclavius
muscle was compressing the vein.
The costoclavicular triangle has the following boundaries: the clavicle superiorly, subclavius
muscle anteriorly, and the first rib and middle scalene muscles posteriorly.
Operative treatment for PSS includes first rib resection, scalene muscle removal, or subclavius
muscle removal, along with removal of constricting scar tissue from around the vein.
Moreover midshaft lacks reinforcement by muscles or ligaments distal to the subclavius
insertion resulting in additional vulnerability.
Other muscles such as trapezius (upper and lower), rhomboids, pectoralis minor and major, subclavius
and latissimus dorsi muscles may be tight and needs to be addressed in the rehabilitation process.
Thoracic outlet syndrome secondary to an anomalous subclavius
Tenodesis of subclavius
in the treatment of recurrent dislocation of the sterno-clavicular joint.
* superior and anterior: the clavicle, subclavius
muscle and costoclavicular ligament
The most common points of venous entrapment are between the anterior and medial heads of the scalenus muscle of the first rib (scalenus anticus syndrome); between the subclavius
muscle, the clavicle and the first rib; and between an anomalous cervical rib and the scalenus muscle.