MUSCLES OF THE APPENDICULAR SKELETON INNERVATION OF BLOOD VESSELS AND NERVES
SCAPULAR AND DELTOID REGIONS; POSTERIOR SECTIONS OF THE ARM
Presenter: Angelie Melzer
MUSCLES OVERVIEW
MUSCLES OF THE BACK: ORIGIN, INSERTION AND ACTION
KEY• O=Origin• I=Insertion• A=Action• N=Nerve
Biomechanical actions of the shoulder:
Flexion, Extension, Abduction, Adduction, Lateral Abduction and Adduction, Internal and External Rotation
Muscles Stabilizing and Moving the Head and Neck
Trapezuius: 3 FibersALL:O= Nuchal Line on the Occipital Protuberance, Ligamentum Nuchae and Spinous Processes of C7-T12.
Upper: I=: Anteriorly on the medial border of the clavicle and posteriorly on the acromionA=Bilaterally: Extend head/neck, Unilaterally:Laterally Flex head and neck on same side, Rotate head to opposite side, Elevate Scapula, Upwardly rotate scapulaMid: I=Spine of the scapula to the spinous processes of T2A=Adduct and stabilize the scapulaLower:I=Spine of the scapula to the spinous processes of T12A=Depress the scapula, Upwardly rotate the scapula
N=Spinal portion of the cranial nerve XI and ventral ramus C2-4
Synergists: Levator scapulae and Rhomboids
Muscles Stabilizing and Moving the Shoulder Girdle and Torso
GLENOHUMERAL JOINT MUSCLES: Deltoid:
O=Lateral 1/3 of the clavicle, acromion and spine of the scapulaI=Deltoid TuberosityA=Shoulder Abduction, Posterior Fibers: Extend, Laterally Rotate and
Horizontally Abduct the shoulders*The anterior and posterior fibers act as antagonists to each other.
N=Axillary C5-6 Rotator Cuff Muscles: SEE NEXT SLIDE
MUSCLES OF THE TORSO: Latissimus Dorsi: O=Inferior angle of scapula, spinous processes of T6-12, last
four ribs, thoracolumbar aponeurosis and posterior iliac crestI=Intertubercular groove of the humerusA=Extend, adduct and medially rotate the shoulderN=Thoracodorsal C6-8
Teres Major: O=Inferior angle and lower 1/3 of lateral border of the scapula
I=Crest of the lesser tubercle of the humerusA=Extend, adduct, medially rotate the shoulderN=Lower subscapular C5-7
*Latissimus Dorsi and Teres Major are synergists.
Rotator Cuff Muscles of the Shoulder• Plate 32 Rotator Cuff Muscles (4)
SupraspinatusO=Suprasinous Fossa of the scapulaI=Greater tubercle of the humerusA=Abduct the shoulder, Stabilize the head of the humerus in
the glenoid cavityN=Suprascapular C4-6
InfrspinatusO=Infrspinous fossa of the scapulaI=Greater tubercle of the humerusA=Laterally rotate, adduct and stabilize the scapulaN=Suprascapular C4-6
SubscapularisO=Subscapular fossa of the scapula
I=Lesser tubercle of the humerusA=Medially rotate and stabilize the shoulderN=Upper and lower subscapular C5-7
Teres MinorO=Upper 2/3 of lateral border of scapulaI=Greater tubercle of the humerusA=Laterally rotate and adduct the shoulder, stabilize the head of the humerusN=Axillary C5-6
NERVE INNERVATION OF THE BACK Brachial Plexus: C5-T1
We must pay close attention the the Brachial Plexus and preserve as much of it as possible during the initial stages of cutting.
Posterior Primary Rami: T2-T12It is interesting to note that the nerves in this region DO NOT supply the surrounding muscles with either motor or sensory innervation. They pierce the Trapezius muscle and become superficial, coursing laterally across the back.
Dermatomes and Cutaneous NervesNerves:
Greater Auricular
Greater and Lesser Occipitals
SupraclavicularBrachial PlexusPosterior
Primary Rami
TERMINOLOGY Synergist: Synchronized Movement Antagonist: Rival, Oppositional Movement Nuchae: Nape of the neck Tuberosity: Protuberance Aponeurosis: Membrane connecting muscles
Trapezius: Transporter, Trapeziod Shape Levator Scapulae: Level, scanning Rhomboids: Rhythmic Deltoid: Delivered Rotator Cuff Muscles: Rotary
Infraspinatus: Informer Supraspinatus: Supress Subscapularis: Submit to, subordinate
Brachial Plexus: The brachial plexus is a network of nerve fibers, running from the spine, formed by the ventral rami of the lower four cervical and first thoracic nerve roots (C5-T1). It proceeds through the neck, the axilla (armpit region), and into the arm.
Posterior Primary Rami: Located between T1-T12, 1 inch lateral to the spinous processes of the thoracic vertebrae. It is interesting to note that the nerves in this region DO NOT supply the surrounding muscles with either motor or sensory innervation. They pierce the Trapezius muscle and become superficial, coursing laterally across the back.
Dermatome: An area of skin supplied by the cutaneous branches of a single nerve. Significant overlapping occurs, therefore, it takes the destruction of at least three consecutive spinal column nerves to have loss a total loss of feeling.
BIBLIOGRAPHY• Biel, Andrew. Trail Guide to the Body, 4th Edition. Boulder, CO:
Books of Discovery. 2010. 66-85.• Clemente, Carmine D. Anatomy: A Regional Atlas of the Human
Body, 6th Edition. Los Angeles: Lippincott, Williams and Wilkins, 2011. 33-34, 38, 40, 44-45, 47, 53, 55, 65, 371-373.
• Clemente, Carmine D. Anatomy Dissector, 3rd Edition. Los Angeles: Lippincott, Williams and Wilkins, 2011.
• Netter, Frank. Atlas of Human Anatomy, 3rd Edition. New Jersey: Novartis. 1999. 148-150,160-163.
• Semenow, Bluhm and Oliver. . Rapid Review: Anatomy Reference Guide, 3rd Edition. Skokie, IL: Lippincott, Williams and Wilkins, 2010. 8-11, 18-21.