Myoelectric manifestations of sternocleidomastoid and
anterior scalene muscle fatigue in chronic neck pain patients.
Neither approach eliminates risk of nerve injury as the dorsal scapular nerve (DSN) and the long thoracic nerve (LTN) travel through the middle scalene muscle, while the phrenic nerve may be placed at risk of injury while traversing along the
anterior scalene muscle. Out-of-plane approaches place the needle trajectory in closer proximity to the phrenic nerve, potentially increasing the risk of mechanical trauma.
Intramuscular hemangioma in the
anterior scalene muscle diagnosed by core needle biopsy.
Upon exiting their respective neural foramina, the roots travel in the interscalene space, bounded anteriorly by the
anterior scalene muscle, posteriorly by the middle/posterior scalene muscles, and inferiorly by the subclavian artery/first rib.
The first site is the interscalene triangle, where compression can occur between the
anterior scalene muscle, middle scalene muscle and the medial surface of the first rib inferiorly.
Christo used a CT scanner to guide the placement of the needle in the patient's
anterior scalene muscle in the neck.
Two of the most important musculoskeletal considerations in TOS are the amount of space between the rib and clavicle, the costoclavicular space and interscalene triangle (the space bounded by the
anterior scalene muscle anteriorly), the middle scalene posteriorly, and the first rib inferiorly.
The subclavian artery travels through the interscalene triangle with the plexus, while the subclavian vein courses anteriorly to the
anterior scalene muscle. The trunks divide into anterior and posterior "divisions" just lateral to the interscalene triangle.
Anterior scalene muscle arises from the anterior tubercles of the transverse processes of third or fourth to the sixth cervical vertebrae (Hollinshead, 1968).
The results revealed increased electromyographic amplitude of the large superficial sternocleidomastoid, and
anterior scalene muscles in patients with neck pain.
(2,4,6,10,11) Compression of the vein in the thoracic outlet through lateral abduction of the arm or hypertrophy of subclavian or
anterior scalene muscles can cause turbulence in the vein, which is exacerbated by increased venous flow experienced during exercise.
Repeatability of surface EMG variables in the sternocleidomastoid and
anterior scalene muscles. European Journal of Applied Physiology 87: 542-549.
