shoulder girdle and brachial plexus anatomy
TRANSCRIPT
Shoulder Girdle and Brachial Plexus Anatomy
Presenter Dr Junaid AhmadPost Graduate Registrar JB&RSC
• Surface Anatomy• Sensory Supply• Bones• Muscle Attachments
Surface Anatomy
Dermatomes of Shoulder
Lymphatics and Superficial Veins
Bones and Joint
• Bones of Shoulder– Clavicle– Scapula– Humerus– Muscle also originate from skull, ribs, sternum and
spines
• Joint– Shoulder Joint– Acromio Clavicular Joint
Clavicle
Clavicle
Fractures of Clavicle
LocationMedial two third and lateral one third
junctionComplications
Nerve entrapments supraclavicular nerveMostly need little treatment
Non Fracture Conditions of Clavicle
Compressions due to narrow spaceBrachial plexusSubclavian Artery and Vien
HumerusScapula
HumerusScapula
HumerusScapula
HumerusScapula
Fractures of Scapula
Associated with high energy run oversAlso fractured ribs mostlyMostly need little treatment
Non fracture conditions of Scapula
DroppingDue to Trapezius paralysis
WingingDue to serratus anterior paralysis
How to check
Common Fractures of Humerus
• Humeral Head Fractures• Greater Tuberosity Fractures• Lesser Tuberosity Fractures• Surgical Neck Fractures• Fractures of the Shaft of the Humerus
• Radial Nerve
• Supracondylar fractures • VIC
• The medial epicondyle
Common Fractures of Humerus
AP X-Ray Shoulder
Axilla
• Pyramidal in shape• Apex in neck• Four walls• Contains vessles, nerves and lymphatics
Walls of Axilla
• Anterior wall• By the pectoralis major, subclavius, and pectoralis minor muscles
• Posterior wall• By the subscapularis, latissimus dorsi, and teres major muscles
from above down
• Medial wall• By the upper four or five ribs and the intercostal spaces covered by the
serratus anterior muscle
• Lateral wall• By the coracobrachialis and biceps muscles in the bicipital groove of
the humerus
Walls of Axilla
Pectoralis Major Muscle
• Origin• Sternum, Upper 6 costal cartilages, Clavicle
• Insertion• Lateral lip of bicipital groove of humerus
• Nerve Supply• Medial and lateral pectoral nerves from brachial
plexus (B.P) C6,7,8
• Function• Adduct and medially rotate the arm
Pectoralis Major Muscle
Pectoralis Minor Muscle
• Origin• 3rd 4th and 5th ribs
• Insertion• Coracoid process of scapula
• Nerve Supply• Medial pectoral nerve from B.P C7
• Function• Depress the shoulder / Elevate the ribs
Pectoralis Minor Muscle
Subclavius Muscle
• Origin• 1st costal cartilage
• Insertion• Clavicle
• Nerve Supply• Nerve to subclavius from upper trunk of B.P C5
• Function• Depress the clavicle
Serratus Anterior Muscle
• Origin• Upper 6 ribs
• Insertion• Medial border and inferior angle of scapula
• Nerve Supply• Nerve to serratus anterior from roots of B.P C6,7
• Function• Rotate scapula / Draw it forwards
Serratus Anterior Muscle
Trapezius Muscle
• Origin• Ligamentum nuchae of occipital bone, 7th spine and all thoracic
vertebrae
• Insertion• Lateral third of clavicle, acromion and spine of scapula
• Nerve Supply• Spinal part of accesory nerver IX
• Function• Upper fibers elevate scapula• Middle fibers pull the scapula medially• Lower fibers pull scapula downwards
Trapezius Muscle
Latismus Dorsi Muscle
• Origin• Iliac crest, lumbar fascia, spines of lower six thoracic vertebrae,
lower three or four ribs, and inferior angle of scapula
• Insertion• Floor of bicipital groove of humerus
• Nerve Supply• Thoracodorsal nerve C7
• Function• Extends, adducts, and medially rotates the arm
Latismus Dorsi Muscle
Rhomboid Major Muscle
• Origin• 2nd to 5th thoracic spines
• Insertion• Medial border of scapula
• Nerve Supply• Dorsal scapular nerve
• Function• Raises medial border of scapula upward and medially
Rhomboid Minor Muscle
• Origin• Ligamentum nuchae and spines of seventh cervical
and first thoracic vertebrae
• Insertion• Medial border of scapula
• Nerve Supply• Dorsal scapular nerve
• Function• Raises medial border of scapula upward and medially
Rhomboid Muscles
• Origin
• Insertion
• Nerve Supply
• Function
Levator scapulae Muscle
• Origin• Transverse processes of first four cervical vertebrae
• Insertion• Medial border of scapula
• Nerve Supply• dorsal scapular nerve
• Function• Raises medial border of scapula
Deltoid Muscle
• Origin• Lateral third of clavicle, acromion, spine of scapula (same as
insertion of trapezius)
• Insertion• Middle of lateral surface of shaft of humerus
• Nerve Supply• Axillary nerve C5
• Function• Anterior fibers medially rotate and flex arm• Posterior fibers extend and laterally rotate arm• Middle fibers abducts the arm
Deltoid Muscle
Supraspinatus Muscle
• Origin• Supraspinous fossa of scapula
• Insertion• Greater tuberosity of humerus
• Nerve Supply• Suprascapular nerve C5
• Function• Abducts arm and stabilizes the shoulder
Infraspinatus Muscle
• Origin• Infraspinous fossa of scapula
• Insertion• Greater tuberosity of humerus
• Nerve Supply• Suprascapular nerve C5
• Function• Laterally rotates arm and stabilizes shoulder
Teres minor Muscle
• Origin• Upper two thirds of lateral border of scapula
• Insertion• Greater tuberosity of humerus
• Nerve Supply• Axillary nerve
• Function• Laterally rotates arm and stabilizes shoulder joint
• Origin
• Insertion
• Nerve Supply
• Function
Teres Major Muscle
• Origin• Lower third of lateral border of scapula
• Insertion• Medial lip of bicipital groove of humerus
• Nerve Supply• Lower subscapular nerve C6
• Function• Medially rotates and adducts arm and stabilizes
shoulder joint
Teres Major Muscle
• Origin
• Insertion
• Nerve Supply
• Function
Subscapularis Muscle
• Origin• Subscapular fossa
• Insertion• Lesser tuberosity of humerus
• Nerve Supply• Upper and lower subscapular nerves C6
• Function• Medially rotates arm and stabilizes shoulder joint
• Origin
• Insertion
• Nerve Supply
• Function
First Part of the Axillary Artery
• This extends from the lateral border of the first rib to the upper border of the pectoralis minor
• Relations• Anteriorly: The pectoralis major and the skin. The
cephalic vein crosses the artery • Posteriorly: The long thoracic nerve (nerve to the
serratus anterior) • Laterally: The three cords of the brachial plexus • Medially: The axillary vein
Second Part of the Axillary Artery
• This lies behind the pectoralis minor muscle • Relations• Anteriorly: The pectoralis minor, the pectoralis major,
and the skin• Posteriorly: The posterior cord of the brachial plexus,
the subscapularis muscle, and the shoulder joint • Laterally: The lateral cord of the brachial plexus • Medially: The medial cord of the brachial plexus and the
axillary vein
Third Part of the Axillary Artery
• This extends from the lower border of the pectoralis minor to the lower border of the teres major
• Relations• Anteriorly: The pectoralis major for a short distance; lower down
the artery it is crossed by the medial root of the median nerve • Posteriorly: The subscapularis, the latissimus dorsi, and the teres
major. The axillary and radial nerves also lie behind the artery • Laterally: The coracobrachialis, the biceps, and the humerus. The
lateral root of the median and the musculocutaneous nerves Medially: The ulnar nerve, the axillary vein, and the medial cutaneous nerve of the arm
Quadrangular Space
• The quadrangular space is an intermuscular space, located immediately below the shoulder joint.
• It is bounded above by the subscapularis and capsule of the shoulder joint
• Below by the teres major muscle. • Medially by the long head of the triceps• Laterally by the surgical neck of the humerus.• The axillary nerve and the posterior circumflex humeral
vessels pass backward through this space
Triangular Space
• Teres minor above• Teres major below• Long head of tricepes laterally• Circumflex scapular atery pass through it
• Thank You