upper extremities 1

• DESC: Pectoralis minor


  Flat, thin muscle that is deep to the pectoralis major
• ORIGIN: Pectoralis minor


  Originates from the anterior surfaces of ribs 3-5
• INSERTION: Pectoralis minor


  Inserts into the coracoid process of the scapula
• INNERVATION: Pectoralis minor


  Medial pectoral nerves
• ACTION: Pectoralis minor


  protract and rotate the scapula downward
• Superficial Muscles of the Anterior Thorax

  Pectoralis minor

  Serratus anterior

  Subclavius
• DESC: Serratus anterior


  Fan shaped muscle, lies deep to the scapula
• ORIGIN: Serratus anterior


  ribs 1-8
• INSERTION: Serratus anterior


  Inserts into the vertebral border of the scapula posteriorly
• ACTION: Serratus anterior


  Rotates the scapula upward

  Prime mover to protract and hold the scapula against the chest wall

  Muscle that is used in pushing, punching, rowing
• INNERVATION: Serratus anterior


  long thoracic nerve
• DESC: Subclavius


  Found just underneath the clavicle

  Small cylindrical muscle that extends from the 1st rib to the clavicle
• INNERVATION: Subclavius


  nerve to subclavius
• ACTION: Subclavius


  Stabilize and depress the pectoral girdle
• ORIGIN: Subclavius


  first rib
• INSERTION: Subclavius


  clavicle
• Superficial Muscles of the Posterior Thorax

  Trapezius

  Levator scapulae

  Rhomboids
• DESC: Trapezius


  Diamond shaped muscle

  Found at the superficial part of the back

  Most superficial muscle of the posterior thorax

  Upper fibers, middle fibers, and lower fibers
• ORIGIN: Trapezius


  Originates from the occipital bone above the ligamentum nuchae and the spines of C7 and all the thoracic vertebrae
• INSERTION: Trapezius


  along the acromion of the clavicle and the spine of the scapula
• INNERVATION: Trapezius


  Innervated by accessory nerve (CN11)
• ACTION: Trapezius


  Serves to stabilize, elevate, retract, and rotate the scapula

  The middle fibers can also adduct the scapula

  Its most prominent action is to elevate the shoulders/shrug the shoulders
• DESC: Levator scapulae


  Located at the back end at the side of the neck

  Deep to the trapezius

  Strap like in shape
• ORIGIN: Levator scapulae


  transverse processes of C1-C4
• INNERVATION: Levator scapulae


  Innervated by the dorsal scapular nerve
• INSERTION: Levator scapulae


  Inserted into the medial border of the scapulae
• ACTION: Levator scapulae


  Can elevate and adduct the scapula
• DESC: Rhomboids


  Found on the medial border of the scapulae

  Just below the levator scapulae (rhomboid minor, smaller and superior)
• ORIGIN: Rhomboid major


  spinous processes of T2-T5
• ORIGIN: Rhomboid minor


  spinous processes of C7-T1
• INSERTION: Rhomboids


  Inserted into the medial border of the scapulae
• INNERVATION: Rhomboids


  Dorsal scapular nerve
• ACTION: Rhomboids


  If they act together they can also retract the scapula and rotate it downward
• Muscles Crossing the Shoulder Joint

  Pectoralis major

  Deltoid

  Latissimus dorsi

  Teres major

  Subscapularis

  Supraspinatus

  Infraspinatus

  Teres minor
• DESC: Pectoralis major


  is a large fan shaped muscle that covers the upper portion of the chest

  forms your anterior axillary fold

  divided into your clavicular part and your sternal parts, depending on where it's attached
• ORIGIN: Pectoralis major


  originates from the sternal end of your clavicle, sternum, as well as the cartilage of the the first six ribs
• INSERTION: Pectoralis major


  inserts into the area of the greater tuberosity of your humerus
• INNERVATION: Pectoralis major


  innervated by both your lateral and medial pectoral nerves
• ACTION: Pectoralis major


  Pectoralis major is the prime mover for flexion of your shoulder joint

  Pectoralis major flexes the shoulder joint

  it can also internally rotate and adduct the shoulder
• DESC: Deltoid


  Makes up the roundness of the shoulder

  Thick multipennate muscle

  Common site for intramuscular injections