Shoulder/Arm Group #3 (Rhomboid Major and minor, levator scapula, serratus anterior, pec major and minor, subclavius)
Lymphatic drainage of the breast
- Axillary lymph nodes - medial portion of Breast drains into parasternal nodes and superficial lymphatic pathways talk w/ app breast and abdominal lymphatics
Deltopectoral triangle
AKA clavipectoral triangle -Deltoid, pectoralis Major, and clavicle form triangle - Contains cephalic (enters with deltoid branch of thoracromial artery) - it and medial/lateral pectoral nerves exit
Actions of Serratus Anterior
Abducts scapula Upward scapular rotation Depresses scapula Holds medial border of scapula to rib cage
Actions of Rhomboid Major (AED)
Adduct Scapula Downward scapular Rotation
Action of Pec Major
Adduct Shoulder IR Elevate thorax during inhalation Flex shoulder (upper fibers) -clavicular head Horizontally adduct (upper fibers) Extends shoulder (lower fibers) -Sternocostal head
Action of rhomboid minor
Adduct scapula Scapular downward rotation
Breast fat
Amount determines size of breast Upper right: 60% Upper left: 15% Lower right: 10% Lower left: 5% Nipple: 10%
Intercostal Nerve
Anterior and lateral cutaneous branches
Intercostobrachial Nerve
Branches from 2nd and 3rd lateral cutaneous branches extend into the axilla and medial arm - Joints with medial brachial cutaneous Nn
Innervation of levator scapulae
Cervical Nerve (C3-C4) Dorsal scapular Nerve(C5)
Insertion of Subclavius
Clavicle (inferior surface, middle 1/3)
Pectoralis Major Origin
Clavicle (medial 1/2) - anterior surface Sternum -Anterior surface Costal Cartilage of ribs 1-6 Aponeurosis of external oblique muscle
Blood supply to subclavius
Clavicular branch of thoracoacromial artery
Pec Minor Insertion
Coracoid process -medial border and superior surface
Acromial Branch of Thoracromial Artery
Courses around the coracoid process beneath deltoid - Provides br. to deltoid musc. and ends on acromion
Pectoral fascia
Covers pec major - inferior with anterior abdominal wall fascia - leaves lateral border of pec major to become axillary fascia
Clavipectoral fascia
Covers subclavius and pec minor
Deltoid branch of Thoracromial Artery
Crosses pec minor to run along the cephalic vein b/t deltoid and pectoralis major
clavipectoral fascia
Deep to pectoral fascia and descends from clavicle - Encloses subclavius m. and then the pectoralis minor and is inferior with the axillary fascia as well
Actions of Pec Minor
Depresses Scapula -inferior and anterior Abducts Scapula Downward Scapular Rotation
Actions of Subclavius
Depresses clavicle Elevates clavicle Stabilizes SC joint
Actions of Serratus posterior Inferior
Depresses ribs 9-12 (expiration) - Aerobic activity
Actions of Serratus posterior inferior
Depresses scapula
lactiferous sinuses
Dilated portion of lactiferous ducts
Innervation of Rhomboid Major
Dorsal Scapular (C5)
Innervation of rhomboid minor
Dorsal scapular (C5)
Blood Supply to Rhomboid Major
Dorsal scapular Artery
Blood supply of Levator scapulae
Dorsal scapular Artery
lactiferous ducts
Drain lobules; opens onto nipple
Actions of Serratus Posterior Superior
Elevates scapula
Serratus Posterior superior Action
Elevates superior ribs - inspiration
Serratus anterior Origin
External (lateral) surfaces of lateral parts of ribs 1-8
(Breast Composition: Glandular tissue)
Glandular tissue (modified sweat gland) 15-20 lobules
Serratus posterior inferior insertion
Inferior border of ribs 9-12
Medial Winging
Injured Nerve: Long Thoracic Muscle palsy: Serratus Anterior Physical Exam: Arm Flexion; Push-up motion against a wall Postion of scapula: Entire scapula displaced more medial and superior
Lateral Winging
Injured Nerve: Spinal accessory Muscle palsy: Trapezius Physical Exam: Arm abduction; ER against resistance Position of scapula: Superior angle more laterally displaced
Subclavius Origin
Junction of 1st rib and its costal cartilage (surrounded by clavipectoral fascia)
Lateral pectoral nerve
Larger than medial - Arises from lateral brachial plexus (C5-C7_ - Course on undersurface of pec major - pierces clavipectoral fascia
Blood Supply of Serratus Anterior
Lateral Thoracic Artery (upper part) Thoracodorsal artery (lower part)
Pec Major insertion
Lateral lip of inter tubercular sulcus of humerus
Innervation of Pec Major
Lateral/medial pectoral( C5, C6, C7, C8, T1)
Deep Muscles
Levator Scapulae Rhomboid major and minor Triceps Brachii
Innervation of Serratus Anterior
Long Thoracic Nerve (C5-C7)
Rhomboid Major Insertion
Medial border of scapula - Between spine and inferior border
Insertion of Serratus Anterior
Medial border of scapula (anterior surface) - same as rhomboids
Levator Scapulae Insertion
Medial border of scapula (superior angle)
Innervation of Pec minor
Medial pectoral nerve (C8-T1) - PIERCES and lies lateral
boundaries of breast
Medial: Lateral border of sternum lateral: midaxillary line Superior: 2nd rib inferior: 6th rib Posterior: deep fascia of pectoralis mm and Serratus anterior
Scapular Winging
Most common cause is damage to the long thoracic nerve
Thoracromial artery (atlas pg 379-381)
One fo 2 branches of 2nd part of Axillary Aa - courses pec minor area of upper chest - pierces clavipectorla fascia into 4 branches
Blood supply of Pectoralis major
Pectoral branch of Thoracromial artery
Levator scapulae Origin
Posterior tubercles of the Tranverse Processes of C1-C4
Pectoralis Minor Origin
Ribs 3-5 -near costal cartilages (surrounded by clavipectoral fascia)
Actions of Levator scapulae
Scapular elevation Downward scapular rotation Lateral flexion of neck Rotates neck Extends neck
Rhomboid Minor Origin
Spinous Processes of C6,C7 Nuchal Ligament
Serratus Posterior Superior Origin
Spinous processes of C7-T3 vertebrae
Rhomboid Major Origin
Spinous processes of T1-T4
Serratus posterior inferior origin
Spinous processes of T11-L2 vertebrae
Innervation of Subclavius
Subclavian nerve (C5-C6)
Insertion of Serratus posterior superior
Superior border of ribs 2-4
Arterial supply of the breast
Superolaterally branches from the lateral thoracic Aa - Long thoracic Nn accompanies this artery
Internal thoracic Artery
Supplies breast superomedially
Superficial Muscles
Trapezius Infraspinatus Deltoid Teres Minor and major Serratus Anterior
Innervation of Serratus posterior superior
Ventral rami of intercostal nerve (T2-T5)
Innervation of Serratus posterior inferior
Ventral rami of intercostal nerve (T9-T12)
Medial pectoral nerve
arise from medial Brachial plexus (C8,T1) - goes behind axillary Aa and around to unite in front with the lateral Nn - Enters pec minor and some branch into major
Lateral thoracic artery of Thoracromial Artery
Other of the 2 branches of 2nd part of Axillary Artery (Thoracoacromial 1st branch) - descends along axillary border of pec minor - follows onto thoracic wall and supplies lateral aspect of breast and serratus anterior
Blood Supply to Pec minor
Pectoral branch of thoracromial artery
Superficial to deep structures of pectoral region structures
Pectoral fascia Pectoralis major Clavipectoral fascia Pectoralis minor - More superficial to deep
Scapular winging and purpose of Serratus Anterior
Serratus Anterior protracts, upwardly rotates scapula and keeps it closely opposed to thoracic wall - Optomizes position of glenoid and helps max ROM
Clavicular branch of Thoracromial Artery
Serves sternoclavicular joint - Courses b/t the clavicular head of pec major and clavipectoral fascia ** supplies subclavius Mm
Blood supply to serratus posterior inferior
Superior intercostal Artery
Blood supply to Serratus Posterior Superior
Superior intercostal artery
Quadrants of the breast
Superolateral Superomedial Inferolateral Inferomedial - Superolateral segment contains axillary tail and 50% of breast cancer occurs here
Insertion of Rhomboid Minor
root of scapular spine
