Lecture: Thorax and movements of the scapula

Card Set Information

Lecture: Thorax and movements of the scapula
2012-03-29 00:54:07
Lecture Thorax movements scapula

Lecture: Thorax and movements of the scapula
Show Answers:

  1. Pectoralis Minor
    Origin: anterior surfaces of ribs 3-5 (or 2-4)

    Insertion: coracoid process of scapula

    • Action: with ribs fixed, draws scapula foward and downward
  2. Serratus anterior
    Origin:by a series of muscle slips from ribs 1-8(or9)

    Insertion: entor anterior aurface of vertebral border of scapula

    • Action: rotates scapula so that its inferior anfle moves laterally up and down, prime mover to protract and hold scpaula against chest wall
  3. Subclavius
    Origin: constal cartilage of rib 1

    Insertion: groove on inferior surface of clavicle

    • Action: helps stabilize and depress pectoral girdle
  4. Trapezius
    Origin: occipital bone, ligamentum nuchae, and spinous processes of C7 and all thoracic vertebrae

    Insertion: a continuous insertion along acromion and spone of scapula and lateral third of clavicle

    • action: stabilizes, raises, retracts, and rotates scapula
  5. Levator Scapulae
    origin: transverse processes of c1-C4

    insertion: medial border of the scapula, superior to the spine

    • action: elevates/adducts scapula
  6. Rhomboids
    Origin: spinous processe of C7 and T1 (minor) and spinous processes of T2-T5 (major)

    Insertion: medial border of scapula

    Action: Stabilizes scapula
  7. Pectoralis Major
    Muscles crossing the shoulder joint
    origin: sternal end of clavicle, sternum, cartilage of ribs 1-6 (or 7), and aponeurosis of external oblique muscle

    insertion: fibers converge to insert by a short tendon into intertubercular sulcus and greater tuberacle of humerus

    • action: prime mover of arm flexion; rotates arm medially, adducts arm
  8. Which are the prime movers for arm movement?
    Pectoralis Major

    Latissmus Dorsi

  9. Which four muscles make up the rotator cuff?
    What are their functions?


    Teres Minor


    • They...
    • 1. reinforce the capsule of the shoulder
    • 2. act as synergists and fixators
  10. Deltoid
    Muscles crossing the shoulder joint
    Origin: embraces insertion of the treapezius, lateral third of clavicle; acrominon and spine of scapula

    Insertion: deltoid tuberosity of humerus

    • Action: prime mover of arm abduction when all its fibers contract simultaneously
  11. Latissmus Dorsi
    Muscles crossing the shoulder joint
    Origin: indirect attachment via lumbodorsal fascia into spines of lower siz thoracic vertebrae, lumbar vertebrae, lower 3 to 4 ribs, and iliac crest; also from scapulas's inferior angle

    Insertion: spirals around teres major to insert in floor of intertubular sulcus of humerus

    • action: primse mover of arm extension; powerful arm adductor, medially rotates arm at shoulder
  12. Subscalpularis
    Muscles crossing the shoulder joint
    Rotator Cuff
    origin: subscapular fossa of scapula

    insertion: lesser tubercle of humerus

    action: chief medial rotator of humerus
  13. Supraspinatus
    Muscles crossing the shoulder joint
    Rotator Cuff
    Origin: supraspinaous fossa of scapula

    Insertion: superior pare of greater tubercle of humerus

    Action: intiates abductions
  14. Infraspitaus
    Muscles crossing the shoulder joint
    Rotator Cuff
    Origin: infraspinous fossa of scapula

    Insertion: greater tubercle of humerus posterior to insertion of supraspinatus

    Action: rotates humerus laterally
  15. Teres Minor
    Muscles crossing the shoulder joint
    Rotator Cuff
    Origin: posterior surface of scapula at inderior angle

    Insertion: crest of lesser tubercle on anterior humerus insertion of tendon fused with that of latissmus dorsi

    Action: extends, medially rotates, and adducts humerus
  16. Coarcobrachialis
    Muscles crossing the shoulder joint
    Origin: coracoid process of scapula

    Insertion: medial surface of humerus shaft

    Action: flexion and adduction of the humerus