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TrapeziusKey Points:
EXAMINATION
Overall:
Muscle Function:
Upper Trapezius
Palpation: The muscle bulk above the lateral surface of the clavicle following the muscle line superior to the occiput.
Strength Testing:
Gravity Lessen Test: Position ““ the subject in supine or prone and the head rotated to the opposite side as the one being tested. Stabilize ““ the head. Resist ““ elevation of the shoulder by applying force on the shoulder (in the direction of shoulder depression). Antigravity Test: Position ““ the subject in sitting with arms relaxed on the lap of the subject. Stabilize ““ the trunk and head as needed. Resist ““ elevation of the shoulder with posterolateral cervical extension and head turned so the face is turned contralateral to the side being tested.
Possible Substitutions: Serratus anterior and levator scapulae. Making sure that the face is not turned towards the tested side will help limit this substitution. Additional possible substitutions are through the pectoralis minor and rhomboids.
Middle Trapezius
Palpation: Medial to the root of the spine of the scapula, at approximately the level of T3 vertebrae.
Strength Testing: Position ““ the subject in prone with forehead on a small towel roll and head in neutral position. Shoulder in 90º of abduction with lateral rotation. The upper arm supported on the table and in the same plane as the scapula. The subject may require a pillow under the chest if their anterior muscles are short. Stabilize ““ if the deltoid is weak and support the arm with the scapula pulled laterally to abduct it. This will ensure pure scapular motion. Resist ““ on the forearm and against adduction of the scapula while the subject is pulling the shoulder blades together and lifting the arm with the humerus laterally rotated.
Possible Substitutions: Rhomboids ““ downward rotation of the scapula with adduction is noted with rhomboid substitution. Keeping the humerus in lateral rotation or keeping the thumb pointed towards the ceiling with the shoulder in 90º will resolve this. In addition, the levator scapulae, upper trapezius, and lower trapezius may substitute.
Lower Trapezius
Palpation: Lateral to the spinous processes of the lower thoracic vertebrae, with the fibers inserting in the diagonal upward direction towards the spine of the scapula.
Strength Testing: Position ““ the subject in prone with the forehead on a small towel roll with the head in neutral. The shoulder is abducted to approximately 135º and the arm laterally rotated with thumbs pointed to the ceiling. The intent is to align the arm to the direction of the lower fibers of the trapezius. The arm is supported on the table and on the same plane as the scapula. The subject may require a pillow under the chest if their anterior muscles are short. Stabilize ““ if the deltoid is weak and support the arm with the scapula pulled laterally to abduct it. Resist ““ on the forearm and against the arm elevating off the table while the subject is drawing the scapula down and in.
Possible Substitutions: Rhomboids ““ downward rotation of the scapula is noted with this substitution. Middle trapezius ““ make sure there is scapular adduction with depression and not pure adduction to avoid this substitution. Upper trapezius ““ scapular elevation is witnessed rather than scapular depression during this substation. Latissimus dorsi ““ assists in scapular depression only.
ANATOMY
Innervation:
Origins of Upper Trapezius: External occipital protuberance, medial â…“ of superior nuchal line, ligamentum nuchae, and spinous process of C7 vertebra.
Origins of Middle Trapezius: Spinous processes of T1 through T5 thoracic vertebrae.
Origins of Lower Trapezius: Spinous processes of T6 through T12 thoracic vertebrae.
Insertions of Upper Trapezius: Lateral â…“ of clavicle and acromion process of scapula.
Insertions of Middle Trapezius: Medial margin of acromion and superior lip of spine of scapula.
Insertion of Lower Trapezius: Tubercle at apex of spine of scapula.
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