Muscle Attachments and Insertions-Lab Practical 2 Flashcards
2 points of attachment
- Origin: Doesn’t move when a muscle contracts
2. Insertion: Moves when a muscle contracts
Levator scapulae origin
Vertebrae C1-C4
Levator scapulae insertion
Vertebral border of scapula
Levator scapulae action
Elevates scapula
Pectoralis minor origin
Ribs 3-5
Pectoralis minor insertion
Coracoid process of scapula
Pectoralis minor actions
- When ribs are fixed it pulls the scapula downward and forward
- Assists in inspiration when the scapula is fixed
Rhomboid minor origin
Vertebrae C7-TI😁
Rhomboid minor insertion
Medial border of the scapula
Rhomboid minor action
Adducts the scapula
Rhomboid major origin
Vertebrae T1 and T5
Rhomboid major insertion
Medial scapula border
Rhomboid major action
Adducts the scapula
Subclavius origin
Superior border of rib 1
Subclavius insertion
Inferior border of clavicle
Subclavius action
Depresses the clavicle
Serratus anterior origin
Ribs 1-9
Serratus anterior insertion
Medial border of scapula
Serratus anterior actions
Scapula fixator
Trapezius origin
Nuchal ligament of the occipital bone
Trapezius insertion
The clavicle, scapular spine, and acromion of the scapula
Trapezius actions
- Contraction of all fibers adducts the scapula
- Contraction of upper fibers elevates the scapula
- Contraction of lower fibers depresses the scapula
Deltoid origin
Scapular spine and acromial end of clavicle
Deltoid insertion
Deltoid tuberosity of humerus
Deltoid action
Abduction of arm at shoulder