Back Muscles Flashcards
What are Extrinsic Muscles?
Muscles that are located outside the area they control
What are intrinsic muscles?
Muscles that are located within their area of control
What is thoracolumbar fascia?
Thick and strong fascia that separates each muscle
Function of thoracolumbar fascia
- Provide dynamic stability
- Origin for transverse abdominis, some erector spinae and lats
5 Extrinsic back muscles are
Lats, Traps, Levator scapulae, Rhomboid minor and major
Function of Latissimus Dorsi
Extends, adducts, and medially rotates the humerus
Where is Lats
Extends from spinous process T7 - L5
2 Function of Trapezius
- Elevates, retracts and depresses scapula
- assists in rotation of scapula during abduction of humerus
Where is Traps
Extends from base of skull, ligamentum nuchae & spinous processes of
C7 to T12 to the clavicle, acromion and spine of scapula
Where is Levator scapulae?
Extends from transverse process of C1 - C4 to medial border of scapula
Function of Levator scapulae
Elevates scapula
Function of intrinsic back muscles
- movement of vertebral column
- control posture and stability
- Proprioception for balance
3 layers of intrinsic back muscles
Superficial - splenius, erector spinae
Intermediate - transversospinales
Deep - Segmented muscles
Function of Splenius
Primary extensors of head and neck
Function of Erector spinae
-Extends vertebral column when contracting bilaterally
- Laterally flexes vertebral column with contracting unilaterally
