Bones of Upper Limb (UL) - Vessels & Nerves (PDF)

Bones of Upper Limb (UL): Vessels & Nerves of UL – Part 1 BiBi Singh, DPM September 13, 2024  Describe the scapular region, pectoral girdle, axilla and brachium Describe the bones and fascia of the upper extremity. Objectives S...

Bones of Upper Limb (UL): Vessels & Nerves of UL – Part 1 BiBi Singh, DPM September 13, 2024  Describe the scapular region, pectoral girdle, axilla and brachium Describe the bones and fascia of the upper extremity. Objectives State the course and significance of superficial veins and cutaneous nerves. Describe the brachial plexus and respective branches. Discuss the subclavian artery and its course. Clavicle Scapular Region Muscles in this region arise from the shoulder girdle and are inserted into the humerus. Nerve supply to this region is via the ventral rami of Cn5,6 through branches from the Brachial Plexus  Muscle Origin Insertion Innervation Blood Supply Action Deltoid Lateral 1/3 of clavicle, Deltoid tuberosity of the Axillary nerve (C5,C6) Posterior humeral circumflex and Abduct arm acromion and spine of humerus deltoid branch of the thoraco- Extends arm scapula acromial artery Rotates arm laterally Supraspinatus Supraspinous fossa of Superior facet of greater Suprascapular nerve Suprascapular artery (transverse Assists deltoid in abduction scapula tubercle of humerus (C4,C5,C6) scapular) of arm, when deltoid is paralyzed Scapulohumeral Infraspinatus Infraspinous fossa of scapula Middle facet of Greater Tubercle of humerus Suprascapular nerve (C5,C6) Suprascapular artery (transverse scapular)& Circumflex scapular Rotates arm laterally (Intrinsic) artery Shoulder Teres minor Lateral margin of Inferior facet of greater Axillary nerve (C5,C6) Circumflex scapular artery Rotates arm laterally infraspinous fossa tubercle of humerus Keeps the head of the humerus in place during Abduction Muscles Teres major Dorsal surface of inferior angle of Medial lip of intertubercular groove Lower scapular nerve (C5,C6) Circumflex scapular artery Adducts the arm Medially rotates the humerus scapula Subscapularis Subscapular fossa Lesser tubercle of the Subscapular nerve Lateral thoracic Medially rotates the arm humerus (C5,C6,C7) Subscapular arteries Pectoral Girdle Also known as the “Shoulder Girdle” Bony ring, incomplete posteriorly, formed by the scapula and clavicles Completed anteriorly by the manubrium of the sternum (part of axial skeleton) Axilla The pyramidal interval between the arm and the chest Axilla - Boundaries Base is axillary fascia Anterior axial fold- Pectoralis major & minor Posterior axillary wall – Latissimus dorsi, Teres major and Subscapularis Medially – upper ribs, intercostal muscles and serratus anterior Laterally – intertubercular groove, Biceps brachii Contents of the Axilla Axillary artery & vein Part of Brachial Plexus and Branches Lateral cutaneous Branches of some intercostal nerves Long Thoracic nerve Intercosto-brachial nerve Part of Cephalic Vein Axillary lymph nodes Rotator Cuff Muscles Form a musculotendinous cuff Keeps head of the humerus in place Prevents head of humerus from being pulled against acromion by the Deltoid muscle Easily damaged in sports Rotator Cuff Muscles Rotator Cuff Muscles Females over 60 Injury to rotator cuff from fall Subscapularis tendon is most often damaged and medial rotator is impaired The image is a coronal T1-weighted fat-suppressed MR arthrogram. Partial articular supraspinatus tendon avulsion. Triangular Space Above: Teres minor Below: Teres major Laterally: Medial side of the Long head of the Triceps Contents: Circumflex Scapular Vessels- arteries & veins Quadrangular Space Above: Teres minor Inferior: Teres major Medial: Lateral side of long head of Triceps Contents: Axillary nerve, Posterior Circumflex Humeral Vessels Pectoral Region Connect the upper limb and the thoracic skeleton. The pectoralis major is the only muscle in this group that is inserted into the humerus. The other 3 muscles insert in the shoulder girdle. Pectoral Region Fascia Fascia is attached to the clavicle and the sternum Pectoral fascia surrounds the pectoralis major Axillary fascia forms the floor of the axilla A layer forms axillary fascia- ascends and becomes the suspensory ligament of the axilla A layer continues upward to the as clavipectoral fascia – attaches to the clavicle and covers the subclavius muscle.  Pectoral Region Muscles Muscle Origin Insertion Innervation Blood Supply Action Pectoralis Anterior surface of the medial half Lateral lip of intertubercular Lateral and Perforating Branch of internal Clavicular part –Medially rotates major of the clavicle, anterior sternum, groove of humerus Medial pectoral thoracic artery and flexes the arm costal cartilages 1-6, aponeurosis nerves Pectoral branches from the Sternocostal Part – Depresses arm of external oblique Thoracoacromial artery & Shoulder Adducts the arm Pectoralis Ribs 2-5 Coracoid process of the scapula Medial and Perforating Branch of internal Depresses lateral angle of scapula minor Lateral Pectoral thoracic artery and pulls shoulder forward Nerve Pectoral branches from the Thoracoacromial artery Subclavius Costochondral joint of the first rib Lower surface of clavicle Upper trunk of Clavicular branch of Stabilize sternoclavicular joint the Brachial Thoracoacromial artery Plexus Serratus Outer surface of ribs 1-8 Costal surface of vertebral border Long thoracic Lateral thoracic artery Rotates scapula Anterior of scapula including superior Nerve Abductor of the arm and elevates angle, inferior angle, medial border arm Pulls scapula forward Muscle of forced expiration Blood Vessels of the Upper Extremity Subclavian artery Lies poster to Anterior Scalene muscle Lies on top of first rib. Outer border of first rib the name changes to Axillary artery Axillary artery Outer border of the Teres major the name changes to Brachial artery Brachial Artery In the cubital fossa splits into Radial and Ulnar artery Direct Branches of the Subclavian Artery Internal thoracic artery Vertebral artery Thyrocervical trunk Inferior thyroid artery Transverse cervical artery Suprascapular artery Costocervical trunk Deep cervical artery Highest intercostal artery Descending scapular artery (transverse scapular) Axillary Artery Part 1 Up to pectoralis major Highest/Supreme Thoracic Artery From the 1st part of the axillary artery Thoracoacromial Artery From the 1st to the second part of the Axillary artery Acromial branch – acromion process Clavicular branch – subclavius muscle Pectoral branch – pectoralis major and minor Deltoid branch – accompanies the cephalic vein and supplies the deltoid muscle Axillary Artery Part 2 Lateral thoracic artery Descends down the lateral border of the Pectoralis minor muscle May give off Lateral Mammary Artery branches Axillary Artery Part 3 Subscapular Artery Circumflex scapular artery continues as… Thoracodorsal artery (accompanies Thoracodorsal nerve) which supplies the wall of the Thorax Anterior Circumflex Humeral Artery Supplies surgical neck of the humerus Posterior Circumflex Humeral Artery A descending branch will anastomose with Profunda brachii Venous Drainage Subclavian Vein lies anterior to the Anterior Scalene Muscle Lies on top of the first rib Superficial Veins of the Upper Arm Cephalic vein drains into the Axillary Vein Basilic vein joins the brachial vein to form the Axillary vein Median cubital vein connects the Cephalic and Basilic veins together Scapular Anatomosis Subscapular and Circumflex Scapular arteries along the lateral border of the scapula Descending scapular artery – medial border Suprascapular artery – upper margin of scapula Branches from intercostal arteries (Ribs 2-7) Transverse Cervical Artery Brachial Plexus Formed by the union of Ventral rami of C5,C6,C7,C8 and Ventral ramus of T1 Sometimes a branch from C4 and T2 also join the Brachial Plexus It descends in the neck in the area of the Posterior Triangle above the clavicle and lateral to the Sternocleidomastoid muscle. It may be blocked with anesthetic 1cm above the mid-point of the clavicle Divisions do not give branches Nerves can branch from the rami, but normally branching is from the cords. Brachial Plexus Nerves from the Rami Dorsal scapular nerve (C5) Supply muscles of the shoulder region Phrenic nerve exits near by Pain referred to right shoulder from diaphragm Long thoracic nerve (C5,C6,C7) Intercostobrachial nerve (T1,T2) pain from heart attack will be felt as a tingling sensation in medial aspect of arm Nerves from the Trunks Suprascapular nerve (C5,C6) Nerve to the Subclavius muscle (C5) Nerves from the Cords Lateral Lateral Pectoral Nerve (C5,6,7) Musculocutaneous (C5,6,7) Medial Medial Pectoral Nerve (C8,T1) Ulnar Nerve (C7,8,T1) Medial Cutaneous brachial cutaneous nerve (T1) Medial antebrachial Cutaneous (C8,T1) Posterior Subscapular nerve (C5,C6) Thoracodorsal nerve (C7,C8,T1) Axillary nerve (C5,6) Radial Nerve ( C5,6,7,8) Brachial plexus relationships The brachial plexus is behind the 1st and 2nd parts of the Axillary artery The Posterior cord is posterior to the Axillary artery The Medial cord is medical to the Axillary artery The lateral cord is lateral to the Axillary Artery Brachial Plexus Injuries A. Increase angle between neck & shoulder B. Waiter’s Tip – Injury to superior trunk C. Upper brachial plexus injury due to excessive stretching of the neck D & E Excessive stretching of the neck F Paralysis of muscles supplied by C5 & C6 – Erb-Duchenne Palsy