| Muscle |
 |
|
| Origin |
 |
|
| Insertion |
 |
|
| Action |
 |
|
| Nerve |
 |
|
| Errector Spinae |
Medial - Spinalis
Middle - Longissimus
Lateral - Iliocostalis |
|
Extension and Lateral Flexion of the spine |
Spinal |
| Quadratus Lumborum |
Posterior Iliac Crest |
Transverse Process L1-4 and the 12th Rib |
Lateral flexion to the same side |
Branches of the T12-L1 |
| Trapezius |
Occiput
C7-T12 Spinous Processes |
Lateral 1/3 clavicle
acromion processes and spine to the root of the spine |
elevation
upward rotation
retraction
depression |
accessory |
| Rhomboids Minor |
C7-T1 Spinous Processes |
Root of the spine of the scapula |
retraction of the scapula |
dorsal scapula |
| Rhomboids Major |
T2-5 Spinous Processes |
Vertebral Border from the root of the spine to the inferior angle |
retraction downward rotation of scapula |
dorsal scapula |
| Latissimus Dorsi |
T6 Spinous Processes to Iliac crest and lower 3 or 4 ribs |
Bicipital Groove of humerus |
adduction, extension, and medial rotation of humerus |
thoracordorsal |
| Teres Major |
inferior angle of the scapula |
medial lip of the bicipital groove of the humerus |
extension, medial rotation, and adduction of humerus |
subscapular |
| Deltoid |
Lateral 1/3 clavicle, acromion, spine of the scapula |
deltiod tuberosity |
abduction. flexion, extension, medial and lateral rotation of humerus |
axillary |
| Supraspinatus |
Supraspinous Fossa of the scapula |
upper part of the greater tubercle of the humerus |
abduction of humerus, draws humerus toward glenoid fossa |
supra-scapular |
| Infraspinatus |
Infraspinous fossa of the scapula |
middle portion of the greater tubercle of the humerus |
lateral rotation and horizontal abduction of humerus |
supra-scapular |
| Teres Minor |
Upper axillary border of the scapula |
lower portion of the greater tubercle on the humerus |
lateral rotation of humerus |
axillary |
| Subscapularis |
Subscapular fossa of the scapula |
lesser tubercle of the humerus |
medial rotation of humerus |
subscapularis |
| Levator Scapulae |
C1-C4 |
Vertebral border of scapula between superior angle and spine |
Bilateral-extends the head and neck Laterally- flexes head and neck and rotates head and neck |
Dorsal Scapular |