Functional Anatomy of Major Muscles - Back Musculature

Question 1

Quadratus Lumborum

Answer 1

Isolated function: concentric- spinal lateral flexion
integrated function: eccentric- decelerates contralateral spinal flexion
isometric- stabilizes the lumbo-pelvic-hip complex

Question 2

Latissimus dorsi

Answer 2

Isolated function: concentric-shoulder extension, adduction, and internal rotation
integrated function: eccentric-shoulder flexion, abduction, external rotation, and spinal flexion
isometric-stabilizes the low pelvic complex and shoulder.

Question 3

serratus anterior

Answer 3

Isolated function: concentric-scapular protraction
integrated function: eccentric-scapular retraction
isometric-stabilizes the scapula.

Question 4

rhomboids

Answer 4

Isolated function: concentric- produces scapular retraction and downward rotation.
Integrated function: eccentric-scapular protraction and upward rotation
isometric-stabilizes the scapula

Question 5

Lower trapezius

Answer 5

Isolated function concentric-scapular depression
integrated function: eccentric-scapular elevation
isometric-stabilizes the scapula

Question 6

Middle trapezius

Answer 6

Isolated function: concentric-scapular retraction
integrated function: eccentric-scapular protraction and elevation
isometric-stabilizes scapula

Question 7

Upper trapezius

Answer 7

Isolated function: concentric-cervical extension, lateral flexion and rotation; scapular elevation
function: eccentric-flexion, flexion, rotation, scapular depression
isometric-stabilizes the cervical spine and scapula, stabilizes the medial border of the scapula creating a stable base for the prime movers during scapular abduction and upward rotation.

Question 8

levator scapulae

Answer 8

Isolated function: concentric-cervical extension, lateral flexion and lateral rotation when the scapulae is anchored; assists in elevation and downward rotation of the scapulae

Question 9

Multifidus

Answer 9

Isolated function: concentric-spinal extension and contralateral rotation
integrated function: eccentric-spinal flexion and rotation
isometric-stabilizes the spine

Question 10

iliocostal

Answer 10

Isolated function: concentric-spinal extension, rotation, and lateral flexion
integrated function, eccentric-spinal flexion, rotation, and lateral flexion
isometric-stabilizes the spine during functional movements