Upper Limb Anatomy PDF

THE UPPER LIMB 11/26/2024 11:43:55 AM 1  The Upper Limb Characterized: ✓ its mobility ✓ ability to grasp, strike, & conduct fine motor skills (manipulation) The upper limb is divided into: The Shoulder girdle - joining the arm...

THE UPPER LIMB 11/26/2024 11:43:55 AM 1  The Upper Limb Characterized: ✓ its mobility ✓ ability to grasp, strike, & conduct fine motor skills (manipulation) The upper limb is divided into: The Shoulder girdle - joining the arm to the trunk The Arm (brachium) a muscle - extends from the lower border of teres major to a transverse line drown between the medial and lateral epicondyles of the humerus. 11/26/2024 11:43:55 AM 2 11/26/2024 11:43:55 AM 2  The Forearm (antebrachium) - extends from the transverse line joining the medial and lateral epicondyles of the humerus to the lower cutaneous fold of the wrist Hand - the part below the lower cutaneous fold of the wrist. The arm and forearm are joined at the elbow (cubitus) and the forearm is joined to the hand at the wrist (carpus) 11/26/2024 11:43:55 AM 3 11/26/2024 11:43:55 AM 3 11/26/2024 11:43:55 AM 4 11/26/2024 11:43:55 AM 5 11/26/2024 11:43:55 AM 6 11/26/2024 11:43:55 AM 7 11/26/2024 11:43:55 AM 8 11/26/2024 11:43:55 AM 9 11/26/2024 11:43:55 AM 10 11/26/2024 11:43:55 AM 11 11/26/2024 11:43:55 AM 12 11/26/2024 11:43:55 AM 13 11/26/2024 11:43:55 AM 14 11/26/2024 11:43:55 AM 15  Bones of the upper limb The upper limb contains the following bones 1. Shoulder girdle - Clavicle and scapula 2. Arm - Humerus 3. Forearm - Radius and ulna 4. Hand - Carpals, metacarpals and phalanges 11/26/2024 11:43:55 AM 16 11/26/2024 11:43:55 AM 16 11/26/2024 11:43:55 AM 17  Upper Limb Skeleton Scapula Hummers Radius, ulna Carpals -proximal -distal Digits – Metacarpals – Phalanges 11/26/2024 11:43:55 AM 18  Shoulder girdle (Pectoral girdle) attaches the upper limb to the axial skeleton It forms no articulation with the vertebral column Each of the two shoulder girdles consists of two bones, the clavicle (collar bone) and the Scapula (Shoulder blade). The clavicle forms the anterior component of the shoulder girdle and articulates with the sternum and the scapula. The posterior component, the scapula, is freely suspended from the thorax by complex muscular attachments and articulates with the clavicle and the humerus. 11/26/2024 11:43:55 AM 11/26/2024 11:43:55 AM 19 19  clavicle Pectoral Girdle scapula humerus 11/26/2024 11:43:55 AM 20 11/26/2024 11:43:55 AM 20 11/26/2024 11:43:55 AM 21 11/26/2024 11:43:55 AM 22  Functions of the clavicle and the scapula They join the upper limb to the trunk They increase the range or extent of joint movement at the shoulder They serve as origin and insertion for the muscles of the shoulder girdle. 11/26/2024 11:43:55 AM 23 11/26/2024 11:43:55 AM 23  Clavicle a long slender “S” shaped bone with a double curvature It extends from the sternum laterally and backwards across the first rib to the acromion process of the scapula playing an important role as outrigger in thrusting the scapula away from the chest wall thereby increasing the range of joint movement at shoulder and arm In its fracture, the shoulder falls forward upon the chest. 11/26/2024 11:43:55 AM 24 11/26/2024 11:43:55 AM 24 11/26/2024 11:43:55 AM 25  Clavicle acromial end sternal end 11/26/2024 11:43:55 AM 26 11/26/2024 11:43:55 AM 26  The clavicle ossifies in a membrane and it is the first bone to start ossification at around the 5th week of development. Parts of the clavicle 1. Sternal end - is rounded and articulates with the sternum. It appears quadrangular or triangular in cross section. 11/26/2024 11:43:55 AM 27 11/26/2024 11:43:55 AM 27 2. Acromial end is a flattened part that articulates with the acromion process of the scapula Nearer to the acromial end on the anterior border of the clavicle there is a small thickening called deltoid tubercle 3. Shaft - is the part between the two ends having a double curvature in a horizontal plane 11/26/2024 11:43:55 AM 28 11/26/2024 11:43:55 AM 28 11/26/2024 11:43:55 AM 29 11/26/2024 11:43:55 AM 29  The clavicle is the only long bone without a medullary cavity The part of clavicle between its medial 2/3 (which is convex forward) and its lateral 1/3 (which concave forward) medial to the coracoid process of the scapula is the weakest part and is a frequent site of fracture. 11/26/2024 11:43:55 AM 30 11/26/2024 11:43:55 AM 30  Muscles attached to the clavicle 1. Clavicular head of pectoralis major 2. Deltoid 3. Clavicular head of sternocleidomastoid 4. Lateral part of sternohyoid 5. Trapezius 6. Subclavius Other structures attached to the clavicle 1. Clavipectoral fascia 2. Anterior and posterior sternoclavicular ligaments 3. Interclavicular ligament 11/26/2024 11:43:55 AM 31 11/26/2024 11:43:55 AM 31 11/26/2024 11:43:55 AM 32 11/26/2024 11:43:55 AM 32  The Scapula is a large triangular bone in the dorso-lateral aspect of the thorax at the level of the 2nd - 7th ribs It articulates with the humerus and the clavicle It is separated from the ribs by muscles gliding on the chest wall in what has been termed Scapulothoracic joint 11/26/2024 11:43:55 AM 33 11/26/2024 11:43:55 AM 33 11/26/2024 11:43:55 AM 34 11/26/2024 11:43:55 AM 34  acromion process coracoid process glenoid cavity superior angle Anterior Scapula subscapular fossa inferior angle 11/26/2024 11:43:55 AM 35 11/26/2024 11:43:55 AM 35 Posterior scapula Posterior Scapula acromion process supraspinous fossa infraspinous fossa spine lateral border medial border 11/26/2024 11:43:55 AM 36 11/26/2024 11:43:55 AM 36 11/26/2024 11:43:55 AM 37 11/26/2024 11:43:55 AM 37 11/26/2024 11:43:55 AM 38 11/26/2024 11:43:55 AM 38  The relatively smaller glenoid cavity is enlarged by a fibrocartilaginous rim called glenoidal labrum to accommodate the large head of the humerus Above and below the glenoid cavity there are supraglenoid and infraglenoid tubercles that provide attachment sites for the long heads of biceps and triceps muscles respectively. 11/26/2024 11:43:55 AM 39 11/26/2024 11:43:55 AM 39  The two fossae communicate laterally via the spinoglenoidal notch the supraspinous fossa and the infraspinous fossa On the superior border just medial to the coracoid process is the scapular (suprascapular) notch, which is bridged over by the suprascapular (superior transverse scapular) ligament forming a foramen that transmits the suprascapular nerve to the supraspinous fossa, while the suprascapular vessels ride over the ligament. 11/26/2024 11:43:55 AM 40 11/26/2024 11:43:55 AM 40 11/26/2024 11:43:55 AM 41 11/26/2024 11:43:55 AM 42 11/26/2024 11:43:55 AM 43  Structures attached to the scapula Muscles 1. Deltoid 4. Coracobrachialis 2. Trapezius 5. Long head of triceps 3. Long and short heads of biceps Ligament 1. Coracoclavicular ligament 2. Coracoacromial ligament 3.11/26/2024 Suprascapular 11:43:55 AM ligament 44 11/26/2024 11:43:55 AM 44 11/26/2024 11:43:55 AM 45 11/26/2024 11:43:55 AM 45 11/26/2024 11:43:55 AM 46 11/26/2024 11:43:55 AM 46  HUMERUS has upper end, shaft and lower end. Upper end 1. Head-directed medially, backwards and upwards articulates with the glenoid cavity to form shoulder joint. covered by a hyaline cartilage 2. The line separating the head from the rest of the upper end is called the Anatomical neck. 11/26/2024 11:43:55 AM 47 11/26/2024 11:43:55 AM 47 3. Lesser tubercle is an elevation on the anterior aspect of the upper end. 4. Greater tubercle is an elevation that forms the lateral part of the upper end; its posterior aspect is marked by three impressions, upper, middle and lower. 5. Intertubercular sulcus ( Bicipital groove) The sulcus has medial and lateral lips that represent downwards prolongation of lesser and greater tubercles. 11/26/2024 11:43:55 AM 48 11/26/2024 11:43:55 AM 48  Anterior Humerus lesser medial epicondyle deltoid tubercle trochlea tuberosity coronoid fossa intertubercular groove greater capitulum tubercle lateral epicondyle 11/26/2024 11:43:55 AM 49 11/26/2024 11:43:55 AM 49 11/26/2024 11:43:55 AM 50 11/26/2024 11:43:55 AM 50. 6. The line separating the upper end of the humerus from the shaft is called the surgical neck. Shaft is rounded in the upper half and triangular in the lower half has three borders and three surfaces the shaft of the humerus has three borders: posterior, medial, and lateral. At about the middle on the lateral side there is a V- shaped rough raised area called deltoid tuberosity to which the deltoid muscle is inserted Radial sulcus (radial groove, radial fossa or spiral groove Through this sulcus runs the radial nerve. 11/26/2024 11:43:55 AM 51 11/26/2024 11:43:55 AM 51  Lower End Forms condyle which is expanded from side to side & has articular & nonarticular parts. Articular part 1.Capitulum is a rounded projection which articulates between head of radius 2. Trochlea is a pulley shapes surface. It articulates with the trochlear notch of the ulna. 11/26/2024 11:43:55 AM 52 11/26/2024 11:43:55 AM 52 11/26/2024 11:43:55 AM 53 11/26/2024 11:43:55 AM 54 11/26/2024 11:43:55 AM 54 11/26/2024 11:43:55 AM 55 11/26/2024 11:43:55 AM 55 1.-Three nerves are directly related to the humerus and are therefore liable to injury. -axillary nerve at the surgical neck - radial nerve at the radial groove - ulnar nerve behind the medial epicondyle Clinical features 2 Common sites of fracture are the surgical neck, the shaft & supracondylar region 3 The head of humerus commonly dislocates inferiorly. 11/26/2024 11:43:55 AM 56 11/26/2024 11:43:55 AM 56 11/26/2024 11:43:55 AM 57 11/26/2024 11:43:55 AM 57 11/26/2024 11:43:55 AM 58 11/26/2024 11:43:55 AM 58  BONES OF THE FOREARM These are radius and ulna. RADIUS -lateral bone of the forearm & is homologous with the Tibia. -thinner proximally & progressively thickens distally. has three parts - proximal - shaft - distal 11/26/2024 11:43:55 AM 59 11/26/2024 11:43:55 AM 59 trochlear notch Ulna coronoid process head radial notch olecranon process styloid process 11/26/2024 11:43:55 AM 60 11/26/2024 11:43:55 AM 60  Radius radial tuberosity head styloid process 11/26/2024 11:43:55 AM 61 11/26/2024 11:43:55 AM 61 11/26/2024 11:43:55 AM 62 11/26/2024 11:43:55 AM 62  Proximal end - consists of the head, neck & radial tuberosity 1 Head - is disc shaped & is covered with hyaline cartilage. - has superior concave surface which articulates with capitulum on humerus at the elbow joint. - has articular circumference that rotates in the radial notch of the ulna, covered by hyaline cartilage & surrounded by annular ligament. 11/26/2024 11:43:55 AM 63 11/26/2024 11:43:55 AM 63 11/26/2024 11:43:55 AM 64 11/26/2024 11:43:55 AM 64 11/26/2024 11:43:55 AM 65 11/26/2024 11:43:55 AM 65  Clinical features - Radius commonly fractures ~2cm above its lower end (Colle’s fracture) distal fragment is displaced upwards & backwards ( if upwards & forwards it is called Smith’s fracture ) , caused by a fall on outstretched hand. - A sudden powerful jerk on the hand of a child may dislodge the head of the radius from the grip of the annular ligament, this is known as subluxation 11/26/2024 11:43:55 AM 66 11/26/2024 11:43:55 AM 66  ULNA Is the medial and longer bone of the forearm and is homologous to fibula of lower limb. Its thickness decreases in a distal direction or viceversa. Proximal /Upper End. -Presents the olecranon and coronoid process, and the trochlear and radial notches. 11/26/2024 11:43:55 AM 67 11/26/2024 11:43:55 AM 67 CARPAL BONES The carpus is made up of 8 carpal bones- arranged in two rows. 1. Proximal row contains (from lateral to medial side) scaphoid lunate triquetral pisiform. 2. Distal row contains in the same order - trapezium - trapezoid - capitate - hamate. 11/26/2024 11:43:55 AM 68 11/26/2024 11:43:55 AM 68  Proximal Manus (Hand) Phalanx Middle Carpals (8) Phalanx Distal Phalanx 1 2 3 4 5 Metacarpals (5) 3 Pr o Dis 1 pollex Ph xima Pha tal ala l nx lan x Digits (5) 11/26/2024 11:43:55 AM 69 11/26/2024 11:43:55 AM 69 11/26/2024 11:43:55 AM 70 11/26/2024 11:43:55 AM 70 11/26/2024 11:43:55 AM 71 11/26/2024 11:43:55 AM 71  IDENTIFICATION 1.Scaphoid , is boat shaped and has tubercle on lateral side. 2. Lunate , half moon-shaped or crescentic. 3. Triquetal – is pyramidal in shape, has isolated oval facet on the distal part of the palmar surface. 4. Pisiform , is pea shaped and has only one oval facet on the proximal part of its dorsal surface. 11/26/2024 11:43:55 AM 72 11/26/2024 11:43:55 AM 72 5. Trapezium is quadrangular in shape, and has a crest and a groove anteriorly. It has a concavoconvex articular surface distally. 6. Trapezoid- resembles shoe of a baby. 7. Capitate- largest carpal bone with a rounded head. 8. Hamate – is wedge shaped with a hook near its base 11/26/2024 11:43:55 AM 73 11/26/2024 11:43:55 AM 73 CLINICAL FEATURES Commonest injuries which occur in the carpus are fracture of the scaphoid and dislocation of the lunate. METACARPAL BONES These are 5 miniature long bones, which are numbered from lateral to medial side. Each bone has a head (placed distally), a shaft and a base (at the proximal end) 11/26/2024 11:43:55 AM 74 11/26/2024 11:43:55 AM 74  PHALANGES There are 14 phalanges in each hand, 3 for each finger and 2 for the thumb. Each phalanx has a base , a shaft and a head. 11/26/2024 11:43:55 AM 75 11/26/2024 11:43:55 AM 75 11/26/2024 11:43:55 AM 76 11/26/2024 11:43:55 AM 76 11/26/2024 11:43:55 AM 77 11/26/2024 11:43:55 AM 77  SESAMOID BONES OF THE UPPER LIMB. Sesamoid bones are small rounded masses of bone located in some tendons at points where they are subjected to great pressure. 1. Pisiform is often regarded as sesamoid bone lying with in flexor carpi ulnaris. 2. Two sesamoid bones are always found on the palmar surface of the hand of 1st metacarpal bone. 11/26/2024 11:43:55 AM 78 11/26/2024 11:43:55 AM 78 11/26/2024 11:43:55 AM 79 11/26/2024 11:43:55 AM 79 3. One sesamoid bone is found in the capsule of interphalangeal joint of the thumb, in 75% of subjects. 4. One sesamoid bone is found on the ulnar side of intercarpophalangeal joint of little finger~ 75% of subjects. 5. Less frequently there is a sesamoid on lateral side of the metacarpophalangeal joint of index finger. 6. sometimes found on other metacarpophalangeal joints. 11/26/2024 11:43:55 AM 80 11/26/2024 11:43:55 AM 80 11/26/2024 11:43:55 AM 81 12/05/2008 81  FASCIA FASCIA Fascia is a connective tissue that surrounds muscles, blood vessels, and nerves, binding some structures together while permitting others to slide smoothly over each other Pectoral fascia: invests pectoralis major and is continuous inferiorly with fascia of anterior abdominal wall and lateraly with axillary fascia. 11/26/2024 11:43:55 AM 82 12/05/2008 82  Clavipectoral fascia a layer of deep fascia attaching to the clavicle superiorly. pierced by cephalic v., lateral pectoral n., thoracoacromial a.) and lymphatic nodes CALL It encloses the pectoralis minor m. then continues inferolaterally to attach to the axillary fascia, a part which is called the suspensory ligament of the axilla. 11/26/2024 11:43:55 AM 83 12/05/2008 83 11/26/2024 11:43:55 AM 84 12/05/2008 84  Axillary fascia The axillary fascia as part of the superficial fascia of the body lies under the skin in the axilla stretching between the lateral border of pectoralis major muscle and the anterior border of the latissimus dorsi muscle It is continuous anteriorly with pectoral fascia and laterally with the fascia brachii. 11/26/2024 11:43:55 AM 85 12/05/2008 85 11/26/2024 11:43:55 AM 86 12/05/2008 86  Brachial fascia : deep fascia which forms a tubular investment of the arm attached to the humerus via medial and lateral intermuscular septae and divide the arm in to ant. and post. Compartments continuos superiorly with deltoid, pectoral,axillary and infraspinuos fascia. 11/26/2024 11:43:55 AM 87 12/05/2008 87 11/26/2024 11:43:55 AM 88 12/05/2008 88  Bicipital aponeurosis: an extension of the tendon of the biceps brachii m. that blends with the antebrachial fascia on the medial side of the antecubital fossa it is superficial to the brachial artery and median nerve, but deep to the superficial veins of the upper limb this provides some protection for the deeper structures during venipuncture Venipuncture, also known as venepuncture, is the process of inserting a needle inside the vein or intravenously, in order to draw blood from it 11/26/2024 11:43:55 AM 89 12/05/2008 89  The fascia of the arm is continues with the fascia of the forearm, which extends between the olecranon process and distal end of ulna being attached to its posterior surface Intermuscular septae arising from it divide the forearm muscles in to flexor and, extensor groups At the wrist it is thickened to form two retinacula 11/26/2024 11:43:55 AM 90 12/05/2008 90 11/26/2024 11:43:55 AM 91 12/05/2008 91  1) Flexor retinaculum – lies between the pisiform and hamate bones on one side and the scaphoid and trapizium on the other side Behind the flexor retinaculum the joint between the carpal bones forms a ventrally concave sulcus to form the carpal canal or tunnel. 11/26/2024 11:43:55 AM 92 12/05/2008 92 11/26/2024 11:43:55 AM 93 12/05/2008 93 Structures traversing the retinacula of the wrist I. Flexor retinaculum Structures passing through the carpal tunnel 1. Tendon of flexor pollicis longus muscle 2. Tendon of flexor digitorium superficialis muscle 3.Tendon of flexor digitorum profundus muscle 4.Median nerve 11/26/2024 11:43:55 AM 94 12/05/2008 94 B. Outside the carpal tunnel 1.Tendon of palmaris longus muscle 2.Ulnar artery and vein 3. Ulnar nerve 4.Tendon of flexor carpi ulnaris 5.Antebrachial veins 6.Tendon of flexor carpi radialis 11/26/2024 11:43:55 AM 95 12/05/2008 95 11/26/2024 11:43:55 AM 96 12/05/2008 96 11/26/2024 11:43:55 AM 97 12/05/2008 97 In the carpal tunnel, compression of the median nerve can occur due to various causes usually by the fibres of the flexor retinaculum resulting in pain and paresthesia (tingling, burning and numbness) in the hand in the area of distribution of the median nerve. This is called carpal tunnel syndrome. 11/26/2024 11:43:55 AM 98 12/05/2008 98  2. Extensor retinaculum found on the dorsal aspect of the lower part of the forearm or the wrist It overlies 6 compartment containing extensor tendons and called osseofoscial or osseofibrous tunnels. 11/26/2024 11:43:55 AM 99 12/05/2008 99 11/26/2024 11:43:55 AM 100 12/05/2008 100 11/26/2024 11:43:55 AM 101 12/05/2008 101  Structures passing anterior to the Extensor retinaculum through the osseofascial tunnels 1.Tendon of abductor pollicis longus muscle 2.Tendon of extensor pollicis brevis muscle 3.Radial artery and vein 4.Tendon of extensor pollicis longus muscle 5.Tendon of extensor carpi radialis longus muscle 6.Tendon of extensor carpi radialis brevis muscle 11/26/2024 11:43:55 AM 102 12/05/2008 102 7. Tendon of extensor indicis muscle 8. Tendon of extensor digitorum muscle 9. Tendon of extesor digiti minimi muscle 10. Tendon of extesor carpi ulnas muscle B. Structures passing posterior to the extensor retinaculum (outside the osseofascial tunnels) 1. Superficial radial nerve 2. Cephahlic and basilic veins 11/26/2024 11:43:55 AM 103 12/05/2008 103  palmar aponeurosis: a thickening of the deep fascia covering the palm of the hand composed of very dense connective tissue that extends out into each of the fingers as fibrous tendon sheaths It is thick tendinous, triangular compartment of the palm It’s apex, located proximally, is continuous with the tendon of palmaris longus The base is formed by superficial transverse palmar ligament. 11/26/2024 11:43:55 AM 104 12/05/2008 104 11/26/2024 11:43:55 AM 105 12/05/2008 105 11/26/2024 11:43:55 AM 106 12/05/2008 106 Dupuytren’s contracture- is a disease of the palmar fascia resulting in thickening and contracture of the fibrous bands on the palmar surface of the hand and the fingers It usually affects the medial half of the palmar aponeurosis resulting in a progressive flexion of the little and ring fingers at the metacarpophalangeal and proximal interphalangeal joints. 11/26/2024 11:43:55 AM 107 12/05/2008 107 Superficial Veins of the Upper Limb superficial veins of the upper limb: the basilic vein (medial,superficial in forearm, pierces brachial fascia, runs parallel to brachial artery and merges to form axillary vein at axilla). The cephalic vein (lateral, anterior to elbow, communicates with median cubital vein, pierces clavipectoral fascia to empty into axillary vein) originate in the subcutaneous tissue of the dorsum of the hand from the dorsal venous network 11/26/2024 11:43:55 AM 108 12/05/2008 108 11/26/2024 11:43:55 AM 109 12/05/2008 109  The Axillary Vein Formed from the union of the brachial veins and the basilic vein at the inferior border of major teres minor lies on medial side of axillary artery Ends at lateral border of 1st rib where it becomes the subclavian vein The cephalic vein enters the axillary vein close to its transition 11/26/2024 11:43:55 AM to subclavian vein 110 12/05/2008 110 11/26/2024 11:43:55 AM 111 12/05/2008 111 Deep Veins of Arm paired veins which accompany brachial artery Encompass the artery within a common vascular sheath Begin at elbow by union of radial and ulnar veins End by merging with the basilic vein to form the axillary vein The brachial veins contain valves 11/26/2024 11:43:55 AM 12/05/2008 112 112  Superficial Veins of the Forearm The cephalic vein forms over the anatomical snuffbox from the lateral side of the dorsal venous network. The basilic vein arises from the medial side of the dorsal venous network. The median antebrachial vein begins in the superficial venous palamr arch and usually ends in the basilic vein. The perforating veins form communications between the superficial and deep veins 11/26/2024 11:43:55 AM 113 12/05/2008 113 11/26/2024 11:43:55 AM 114 12/05/2008 114  Deep Veins of the Forearm Deep veins accompanying the arteries are plentiful in the forearm These veins arise from deep venous arcade (a series of anastamosing venous arches) in the hand Paired radial and paired ulnar veins arise and accompany the arteries, anastamosing freely. 11/26/2024 11:43:55 AM 12/05/2008 115 115  Lymphatic drainage The superficial vessels accompany the superficial veins in the fore arm until the elbow, where they enter lymph nodes (cubital or epitrochlear). From the elbow most of the vessels run with the basilic vein to the superficial axillary lymph nodes. The deep vessels follow the arteries and they similarly open in to the superficial axillary nodes. The lymph from the superficial axillary nodes is drained to the deep axillary lymph nodes and then to the subclavian trunk. 11/26/2024 11:43:55 AM 116 12/05/2008 116 11/26/2024 11:43:55 AM 117 12/05/2008 117  Axillary Lymph Nodes Five principal groups: pectoral (anterior):lies along the medial wall of axilla. Receive lymph from the anterior thoracic wall. Subscapular (posterior):receive lymph from the posterior thoracic wall and scapula. Humeral (lateral):receive lymph from u.limb Central: receive lymph vesseles from the above three groups. Apical: receive lymph from all groups and lymph vesseles accompanying cephalic vein. 11/26/2024 11:43:55 AM 118 12/05/2008 118 11/26/2024 11:43:55 AM 119 11/26/2024 11:43:55 AM 120 12/05/2008 120 Cutaneous Nerves of Upper Limb A cutaneous nerve is a nerve that provides nerve supply to the skin C3 and C4 innervate base of neck C5 supplies the arm laterally C6 supplies the forearm laterally and the thumb C7 supplies the middle fingers and middle posterior surface of limb C8 supplies little finger, medial side of hand and forearm T1 supplies middle of forearm to axilla T2 supplies skin of axilla 11/26/2024 11:43:55 AM 121 12/05/2008 121 11/26/2024 11:43:55 AM 122 11/26/2024 11:43:55 AM 123 11/26/2024 11:43:55 AM 124 11/26/2024 11:43:55 AM 125 12/05/2008 125 11/26/2024 11:43:55 AM 126 12/05/2008 126 - Most cutaneous nerves of upper limb are derived from the Brachial Plexus - The nerves of the shoulder however are derived from the cervical plexus 11/26/2024 11:43:55 AM 127 12/05/2008 127  Cutaneous Nerves are: The supraclavicular nerve (C3 and C4) Posterior cutaneous nerve of arm(C5-8) Posterior cutaneous nerve of forearm(C5-8) Superior lateral cutaneous nerve of arm(C5,6) Inferior lateral cutaneous nerve of arm(C5,6) Lateral cutaneous nerve of forearm(C6,7) Medial cutaneous nerve of arm(C8-T2) Medial cutaneous nerve of forearm(C8,T1) Intercostobrachial (T2) 11/26/2024 11:43:55 AM 12/05/2008 128 128 11/26/2024 11:43:55 AM 129 12/05/2008 129  Axillary region In the axillary region two parts should be distinguished. 1. Axillary fossa (arm pit) 2. Axillary cavity (Axilla) Axillary fossa - is the visible deepening or groove between the arm and the lateral thoracic wall. 11/26/2024 11:43:55 AM 130  Boundaries - Anterior - anterior axillary fold - Posterior - posterior axillary fold - Lateral - medial side of the upper part of the arm. - Medial - lateral wall of the thorax The anterior axillary fold is formed by pectoralis major muscle while the posterior axillary fold is formed by the latissimus dorsi and teres major muscles 11/26/2024 11:43:55 AM 131  Axilla - is a pyramidal space.. Its base is formed by the axillary fascia.. Its apex open to the lateral neck region through a triangular space between the first rib, the clavicle and scapula. This space is known as cervicoaxillary canal. The main function of the axilla is to transmit and protect blood vessels and nerves that run from the neck to the arm or vice versa. 11/26/2024 11:43:55 AM 132  In the upper part of the axilla these vessels and nerves are related to each other in such a way that the axillary vein lies ventromedial (ventral), the axillary artery at the middle and the brachial plexus dorsolateral (dorsal). Additionally the axilla gives a greater possibility of movement to the shoulder girdle. 11/26/2024 11:43:55 AM 133  Walls of the axilla:. Anterior - pectoralis major and minor muscles. Medial - serratus anterior muscle. Lateral -bony part -intertuercular groove of the humerus. Posterior - subscapularis (upper part) - latissimus dorsi and teres 11/26/2024 11:43:55 AM 134 major 11/26/2024 11:43:55 AM 135  The vessels and nerves give important branches in the axilla. Some of these branches run to the posterior aspect of the shoulder by passing through two openings. 1. A medial triangular space or Medial axillary hiatus (interval) - contains the circumflex scapular artery and vein. 2. A quadrangular space or lateral axillary hiatus - containing the axillary nerve and the posterior circumflex humeral vessels (artery and vein). 11/26/2024 11:43:55 AM 136  Related to these on the adjacent part of the arm there is a lateral triangular space that contains the profunda brachii artery and the radial nerve. Contents of the axilla 1. Axillary vessels 2. Infraclavicular part of the brachial plexus 3. Lateral cutaneous branches of the intercostal nerves 4. Axillary lymph nodes 5. Adipose 11/26/2024 11:43:55 AM and areolar tissue 137 11/26/2024 11:43:55 AM 138  Axillary artery The axillary artery is continuous proximally with the subclavian artery and distally with the brachial artery. It begins at the outer border of the upper surface of the first rib and ends at the lower border of teres major muscle after which it becomes brachial artery. 11/26/2024 11:43:55 AM 139 11/26/2024 11:43:55 AM 140  The pectoralis minor muscle crosses over the artery and divides it into three parts. 1. First or proximal part - between the first rib and the medial border of pectoralis minor. 2. Second or posterior part - behind or posterior to the muscle 3. Third or distal part - between the lateral border of pectoralis minor and the lower border of teres major. Each of these parts gives branch to one, two and three arteries respectively. 11/26/2024 11:43:55 AM 141 11/26/2024 11:43:56 AM 142 A. Branch from the first part: Superior thoracic artery - it supplies the muscles and the wall of the thorax in the upper part of the pectoral region. It forms anastomosis with the intercostal and the internal thoracic arteries. Sometimes the superior thoracic artery may arise from the thoracoacromial artery. 11/26/2024 11:43:56 AM 143 B. Branches from the second part: 1. Thoracoacromial artery - gives rise to the following four branches. a. Pectoral branch b. Acromial branch c. Clavicular branch d. Deltoid branch 2. Lateral thoracic artery - descends to the lateral thoracic wall along the lateral border of the pectoralis minor muscle. C. Branches from the third part: 1. Subscapular artery - descends along the lateral border of the scapula and divides in to thoracodorsal and circumflex scapular arteries. 11/26/2024 11:43:56 AM 144  The thoracodorsal artery runs with the thoracodorsal nerve to the latissimus dorsi muscle the circumflex scapular artery turns backwards around the lateral border of the scapula and passes through the medial triangular space to form anastomosis with the suprascapular artery and the deep and superficial branches of the transverse cervical artery in the posterior part of the scapula forming the so called scapular anastomosis This anastomosis provides an adequate collateral blood flow in either directions. 11/26/2024 11:43:56 AM 145 2. Anterior circumflex humeral artery - a small branch that runs dorsally anterior to the surgical neck of the humerus. 3. Posterior circumflex humeral artery - it courses posteriorly around the surgical neck of the humerus with the axillary nerve and passes through the quadrangular space. 11/26/2024 11:43:56 AM 146 11/26/2024 11:43:56 AM 147  Axillary vein The axillary vein that lies anteromedial to the axillary artery is formed by the union of the brachial veins and basilic veins and drains into the subclavian vein. Below the clavicle its lumen is kept open by the clavipectoral fascia, because of which the axillary its open injury results in air embolism. vein open is kept Its tributaries correspond to the branches of the axillary artery, which are venae commitantes. Venae comitantes are pairs or multiple veins that closely accompany an artery. 11/26/2024 11:43:56 AM 148 11/26/2024 11:43:56 AM 149  Brachial plexus The brachial plexus is mainly formed by the ventral rami of the spinal nerves C5 - C8 and Th1, but sometimes C4 and T2 may also contribute. If the contribution of C4 is larger than that of T2, then the plexus C4 – C8 is known as prefixed and if the contribution of T2 is larger than that of C4, the plexus thus formed by C6 - T2 is called post-fixed. 11/26/2024 11:43:56 AM 150  The brachial plexus passes through the scalen gap and enters the axilla through the cervicoaxillary canal behind the clavicle. Therefore supraclavicular and Infraclavicular parts can be distinguished. In the supraclavicular part the three trunks of the brachial plexus are formed. 1. Upper (superior) trunk - formed by roots from C5 and C6 2. Middle trunk - formed by the root from C7 3.11/26/2024 Lower (inferior) 11:43:56 AM trunk - formed by roots151 from C8 and T1  After passing between the clavicle and the first rib it becomes the infraclavicular part where the trunks branch in to ventral and dorsal divisions and the divisions of the three trunks fuse with each other to form three cords or fasciculi The dorsal divisions of all the three trunks form the posterior cord The ventral divisions of the upper and middle trunks form the lateral cord whereas the ventral division of the lower trunk forms the medial cord. 11/26/2024 11:43:56 AM 152  These three cords (posterior, lateral and medial) give the following branches to the shoulder girdle, the arm and forearm and extend. 1. Posterior cord - axillary and radial nerves 2. Lateral cord - musculocutaneous nerve and lateral root of median nerve. 3. Medial cord - ulnar nerve, medial root of median nerve, medial cutaneous nerve of the arm (medial brachial cutaneous nerve) and the medial cutaneous nerve of the forearm (medial antebrachial cutaneous nerve). 11/26/2024 11:43:56 AM 153  Branches of the brachial plexus to the shoulder girdle All the branches of the brachial plexus to the shoulder girdle are motor nerves except the axillary nerve that has both motor and sensory components. To these nerves belong: 1. Dorsal scapular nerve (C4 & C5 mainly from C5) - passes through the scalenus medius muscle and innervates the levator scapulae, and rhomboid major and minor.. It runs in the direction of the scapula under theAMrhomboid muscles. 11/26/2024 11:43:56 154 11/26/2024 11:43:56 AM 155 11/26/2024 11:43:56 AM 156 11/26/2024 11:43:56 AM 157 2. Long thoracic nerve (C5, C6 & C7) - It also passes through the scalenus medius muscle and descends dorsal to the brachial plexus and the first part of the axillary artery along the midaxillary line to the serratus anterior muscle.. In its paralysis the arm can not be elevated in addition to the appearance of a clinical condition known as winged scapula or scapula alata (this is a condition where the medial border of the scapula protrudes away from the thoracic wall). 11/26/2024 11:43:56 AM 158 3. Nerve to subclavius or subclavius nerve (C5) - innervates the subclavius muscle and the sternoclavicular joint.. Frequently it contributes fibres to the phrenic nerve as accessory phrenic nerve. 4. Medial pectoral (C8 & Th1) and lateral pectoral (C5 - C7) - innervate the pectoralis major and minor muscles. 5. Suprascapular nerve (C5 & C6) - it is the upper most branch of the trunk of the brachial plexus running with the suprascapular vessels to reach the supra- and 11:43:56 11/26/2024 infraspinatus AM muscles. 159  In its paralysis the scapular spine becomes prominent and the lateral rotation of the shoulder joint is affected. 6. Subscapular nerves (C5 & C6) - they are two in number a. Upper (superior) subscapular - small and enters the upper part of subscapularis muscle and teres minor muscle. b. Lower (inferior) subscapular - innervates the lower part of subscapularis muscle and teres major muscle. 11/26/2024 11:43:56 AM 160 7. Thoracodorsal nerve (C6 - C8) - also referred to as middle Subscapular nerve for it arises from the posterior cord between the upper and lower Subscapular nerves.. It runs with the thoracodorsal vessels to the latissimus dorsi muscle. 8. Axillary or circumflex nerve (C5 & C6) - it runs through the quadrangular space being related to the surgical neck of the humerus. Therefore it can be injured by fracture of the surgical neck, subluxation of the shoulder and by a crutch pressing 11/26/2024 11:43:56 AM 161. It gives a motor supply to the deltoid and teres minor muscles.. Its paralysis results in the atrophy of these muscles and loss of sensation in the lower half of the deltoid region.. The paralysis and atrophy of the deltoid muscle results in a prominent greater tuberosity and impairment of abduction of the arm. 11/26/2024 11:43:56 AM 162 11/26/2024 11:43:56 AM 163  Branches of the brachial plexus to the arm The brachial plexus gives six branches to the arm. Out of the six two of them are cutaneous sensory nerves and four of them are mixed nerves. a. Cutaneous nerves as direct branches of the brachial plexus 1. Medial cutaneous nerve of the arm or medial brachial cutaneous nerve (C8 & Th1) 2.11:43:56 11/26/2024 Medial AM cutaneous nerve of the fore164 b. Mixed branches 1. Musculocutaneous nerve (C5 - C7) 2. Median nerve (C6 - Th1) 3. Ulnar nerve (C7 - Th1) 4. Radial nerve (C5 - C8) 11/26/2024 11:43:56 AM 165  Classification of branches of the brachial plexus Branches of the brachial plexus can be classified with reference to the clavicle as branches from the supraclavicular part and branches from the infraclavicular part or on the basis of the different parts of the brachial plexus as branches from the roots, from the trunks and from the cords. 11/26/2024 11:43:56 AM 166 1. Classification with reference to the clavicle A. Branches from the supraclavicular part 1. Subclavius nerve 2. Dorsal scapular nerve 3. Suprascapular nerve 4. Long thoracic nerve B. Branches from the infraclavicular part 1. Branches to the shoulder girdle a. Medial and lateral pectoral nerves b. Subscapular nerves 11/26/2024 11:43:56 AM 167 c. Thoracodorsal nerve  2. Branches to the arm a. Musculocutaneous nerve b. Median nerve c. Ulnar nerve d. Medial brachial cutaneous nerve e. Medial antebrachial cutaneous nerve f. Radial nerve g. Axillary nerve 11/26/2024 11:43:56 AM 168 2. Classification on the basis of their origin from the parts of the brachial plexus. A. Branches from the roots 1. Dorsal scapular (C4 & 5) 2. Long thoracic (C5, 6, 7) B. Branches from the trunks 1. Suprascapular nerve - upper trunk 2. Subclavius nerve - upper trunk Sometimes medial pectoral from the lower trunk and lateral pectoral nerve from the anterior division of the upper and middle trunk of the brachial plexus. 11/26/2024 11:43:56 AM 169  C. Branches from the cords 1. From the lateral cord MLL a. Lateral pectoral b. Musculacutaneous c. Lateral root of median 2. From the posterior cord ULTRA a. Upper subscapular b. Thoracodorsal (Middle subscapular) c. Lower subscapular d. Radial e. Axillary 11/26/2024 11:43:56 AM 170  3. From the medial cord UMMM a. Medial pectoral b. Medial brachial cutaneous c. Medial antebrachial cutaneous d. Ulnar e. Medial root of median 11/26/2024 11:43:56 AM 171 Injuries to Brachial plexus The brachial plexus becomes completely paralysed only in severe injuries but usually some parts of it are injured. Its injury that frequently occurs during delivery is called brachial birth paralysis. Three types of such paralysis are recognised 1.Whole arm paralysis 2.Erb’s palsy of the arm and 3 Klumpke's paralysis of forearm. 11/26/2024 11:43:56 AM 172 11/26/2024 11:43:56 AM 172  Erb’s Duchenne paralysis or palsy It is due to injury to nerves arising from C5 and C6 (upper trunk). Musculocutaneous n, axillary n suprascapular n ,n to subclavius are injured Is the most common type of brachial plexus injury. Characterised by paralysis and atrophy of the deltoid, flexor muscles and the long supinator muscles of the arm, in which case flexion and supination are weakened, abduction and lateral rotation are lost 11/26/2024 11:43:56 AM 173 11/26/2024 11:43:56 AM 173  The arm and hand then assume the Waiter's tip position (a medial rotated upper limb hanging by the side), sensation is lost over the deltoid and radial side of the forearm and hand. The injury is usually caused by traction during delivery and in adults from excessive separation of the head from the neck. Klumpke’s paralysis (Dejerine klumpke’s syndrome) : Injuries to the lower segments C8 and Th1 (lower trunk). Mainly the ulnar nerve is involved. 11/26/2024 11:43:56 AM 174 11/26/2024 11:43:56 AM 174  Manifested by: paralysis of the small muscles of the hand and flexors of the wrist (claw hand) and loss of sensation on the skin area innervated by ulnar n. Causes: Birth trauma or cervical rib. It causes atrophic paralysis of the forearm muscles and small muscles of the hand associated with paralysis of cervical and arm sympathetic innervation( results in oedema of the skin, cyanosis and atrophic nail changes). It can be associated with the injury of the sympathetic PURPLED ON TIP OF FINGER trunk(may lead to Horner’s syndorme ) 11/26/2024 11:43:56 AM 175 11/26/2024 11:43:56 AM 175  Brachial plexus can also be injured by compression e.g. crutch paralysis, Saturday night palsy, etc. RADIAL NERVE If C7 (middle trunk) is involved it leads to the paralysis of triceps, weakness of the extensors of the wrist and fingers. This weakness of the extensors of the wrist and the fingers results in wrist drop of radial nerve type. 11/26/2024 11:43:56 AM 176 11/26/2024 11:43:56 AM 176  Muscles of the shoulder girdle All muscles of the shoulder girdle are involved in the movement and fixation of the shoulder joint and all are innervated by branches of the brachial plexus (except trapezius, which gets additional innervation from the accessory nerve). A. Pectoralis major muscle It has two heads - clavicular& sternocostal O –. Clavicular head - medial half of the clavicle 11/26/2024 11:43:56 AM 177 11/26/2024 177  Sternocostal head - sternum and the related costal cartilages (upper 6) - anterior part of the rectus sheath I - the fibres of the two heads converge and are inserted to the crest of the greater tubercle (lateral lip of the intertubercular sulcus or biceptal groove). 11/26/2024 11:43:56 AM 178 11/26/2024 11:43:56 AM 179 11/26/2024 179  Action 1. Movement - adduction, , medial rotation and depression of the elevated shoulder. Clavicular- flexes ,SC-extends it from flexed postion. 2. Fixation of the shoulder joint N/S - medial pectoral nerve from the medial cord of the brachial plexus and lateral pectoral nerve from the lateral cord of the brachial plexus. 11/26/2024 11:43:56 AM 180 11/26/2024 180 11/26/2024 11:43:56 AM 181  B. Pectoralis minor This is a small muscle under the pectoralis major. O - outer surface of ribs 2 - 5 or 3 - 5 near their costochondral junctions. I - coracoid process of the scapula Action: 1. Movement - depression of the elevated shoulder in a ventrocaudal direction and elevation of the ribs. Therefore it helps in inspiration. 2. Fixation of the shoulder joint N/S - 11:43:56 11/26/2024 11/26/2024 Medial AM and lateral pectoral nerves. 182 182 11/26/2024 11:43:56 AM 183 11/26/2024 183  C. Serratus anterior muscle It also has three parts - horizontal part, divergent part and convergent part. O 1. Horizontal part - ribs 1 and 2 2. Divergent part - ribs 2 and 3 3. Convergent part - ribs 4 - 9 I - costal surface of the scapula along the medial border (superior angle, medial border and inferior angle) Action 1. Movement - moves the scapula on the thorax. The convergent part moves the inferior angle of the scapula anterolaterally(protracts 11/26/2024 11:43:56 AM 11/26/2024 scapula) 184 184 11/26/2024 11:43:56 AM 185 11/26/2024 185  This time the glenoid cavity faces cranially thereby the arm can be elevated above 90. With the scapula fixed, it elevates the ribs and acts as accessory inspiratory muscle. 2. Fixation of the scapula N/S - long thoracic nerve (C5 – C7), the paralysis of which leads to a condition called winged scapula or scapula alata. 11/26/2024 11:43:56 AM 186 11/26/2024 186 11/26/2024 11:43:56 AM 187  D. Subclavius muscle O - near the costochondral junction of 1st rib I - groove for the subclavius muscle on the lower surface of the clavicle Action - fixation of the sternoclavicular joint, i.e. it prevents its upward dislocation. N/S - Nerve to subclavius 11/26/2024 11:43:56 AM 188 11/26/2024 188  E. Teres Minor muscle O - upper part of the dorsal aspect of the axillary border of the scapula I - lower impression of the greater tuberosity and adjoining part of the shaft of humerus. Its tendon runs laterally behind the long head of triceps brachii muscle. Action - lateral rotation, adduction and fixation of the shoulder. N/S - Axillary nerve 11/26/2024 11:43:56 AM 189 11/26/2024 189 11/26/2024 11:43:56 AM 190  F. Teres major O - back of the inferior angle and axillary border of the scapula below the teres minor. I - medial lip of the biceptal groove or intertubercular sulcus. Action - medial rotation, adduction and extension of the shoulder. N/S- lower subscapular 11/26/2024 11:43:56 AM 191 11/26/2024 191 11/26/2024 11:43:56 AM 192 11/26/2024 192  G. Deltoid muscle It is triangular in shape and is divided in to three parts according to the origin of its fibres. The three parts are: Clavicular (anterior fibres) , Acromial (middle fibres) and Spinal parts (posterior fibres). O - clavicular part - lateral 1/3 of the clavicle - acromial part - acromion process of the scapula - spinal part - spine of the scapula I - deltoid tuberosity on the outer surface of the humerus 11/26/2024 11:43:56 AM 193 11/26/2024 193  Action. Clavicular part - flexion, medial rotation and participates in the pulling of the trunk towards a fixed arm, e.g. during climbing.. Acromial part - abduction of the arm up to 90 (but not 1st 15 ). Spinal part - extension, lateral rotation.All the three parts are involved in the fixation of the shoulder joint. N/S - Axillary nerve (C5 - C6) 11/26/2024 11:43:56 AM 194 11/26/2024 194 11/26/2024 11:43:56 AM 195  H. Supraspinatus muscle O - supraspinous fossa of the scapula I - upper part of the greater tubercle of the humerus (upper impression). Action - abduction of the shoulder up to 90, helps in climbing and fixation of the shoulder joint. It responsible for the first 15 of abduction (initiator of abduction) after which it is assisted by deltoid. N/S - suprascapular nerve 11/26/2024 11:43:56 AM 196 11/26/2024 196  I. Infraspinatus muscle O - infraspinous fossa of the scapula I - at the middle of the posterior part (middle impression) of the greater tubercle of the humerus. Action - lateral rotation and is involved in climbing and fixation of the shoulder joint. N/S - suprascapular nerve 11/26/2024 11:43:56 AM 197 11/26/2024 197 11/26/2024 11:43:56 AM 198  J. Subscapularis muscle O - subscapular fossa on the costal surface of the scapula. I - lesser tubercle of the humerus Action - adduction, medial rotation and slight extension; also involved in climbing and fixation of the shoulder joint. N/S - upper and lower subscapular 11/26/2024 11:43:56 AM 199 11/26/2024 199 11/26/2024 11:43:56 AM 200 11/26/2024 11:43:56 AM 201 11/26/2024 11:43:56 AM 202  The subscapularis, supraspinatus, infraspinatus and teres minor form the rotator cuff. This cuff of muscles reinforces the capsule of the shoulder joint and helps to keep the disproportionately large head of the humerus in the shallow glenoid cavity of the scapula during movement of the shoulder joint. 11/26/2024 11:43:56 AM 203 11/26/2024 203 11/26/2024 11:43:56 AM 204  K.Trapezius Has three parts( acc. to the direction of its fibres) 1. Descending or superior part 2. Transverse or middle part 3. Ascending or inferior part O -External occipital protuberance Medial part of the superior nucheal line Ligamentum nachae Spinous processes of all thoracivertebrae 11/26/2024 11:43:56 AM 205  I- Lateral 1/3 of the clavicle (desc. F.) - Acromion process of the scapula (trans. - Scapular spine (ascending fibres) Movement: Desc. F.- Elevation of the shoulder girdle. Trans. F. -retraction of the scapula). Asc. F.-depression of elevated fibers All parts together retracts scapulla Desc. and asc. Parts rotate glenoid cavity superiorly 11/26/2024 11:43:56 AM 206 11/26/2024 11:43:56 AM 207  In. - Spinal part of the accessory nerve, cervical plexus (C3 and C4). L. Latissimus dorsi climbing musce Fan shaped muscle that covers the back O- Inferior angle of the scapula - Spinous processes of thoracic vertebrae 7 - 12, - Spinous processes of all the lumbar vertebrae, sacrum, thoracolumbar fascia ,(9th) 10th - 12th ribs by fleshy fibres - iliac crest 11/26/2024 11:43:56 AM 208 In. - thoracodorsal (Middle scapular) nerve from the posterior cord of the brachial plexus. Action - Medial rotation, adduction and retroversion (extension) of the shoulder - Raises the body during climbing -Forms the inferior angle of the triangle of auscultation. It forms the posterior axillary fold together with teres major. 11/26/2024 11:43:56 AM 209 11/26/2024 11:43:56 AM 210 11/26/2024 11:43:56 AM 211  Triangle of auscultation: a small triangular gap near the inferior angle of scapula where heart and lung sounds hear more clearly. Boundaries – Medial - trapezius Lateral - scapula Inferior - Latissimus Floor -rhomboides major 11/26/2024 11:43:56 AM 212  M.Rhomboid major O - spinous process of Th2 - Th5 and supraspinal lig. I - medial border of the scapula below the spine. In. - dorsal scapular nerve Action - Elevation of the scapula - Retraction of the shoulder - Fixation of the scapula to the trunk. - Downward rotation of the scapula 11/26/2024 11:43:56 AM 213  Rhomboid minor O - spinous process of C7 - lower part of ligamentum nuchae - spinous process of the Th1 I - Medial border of the scapula above spine & above the insertion of rmboid major Inn. And action - Similar to rhomboid major 11/26/2024 11:43:56 AM 214  N.Levator scapulae O-transverse processes of C1-C4 I-superior part of medial border of scapula –Inn.dorsal scapular n Action-elevates scapula 11/26/2024 11:43:56 AM 215 11/26/2024 11:43:56 AM 216 11/26/2024 11:43:56 AM 217 11/26/2024 11:43:56 AM 218  MUCLES OF THE UPPER LIMB Muscles of the arm The muscles of the arm are divided in to extensors ( the posterior compartment) and flexors ( anterior compartment. Muscles of the same compartment are similar in: Their actions on the elbow joint Innervation and development Have the same covering fascia 11/26/2024 11:43:56 AM 219 11/26/2024 11:43:56 AM 220 Flexor group of arm muscles This group is composed of three muscles, namely biceps brachii, coracobrachialis and brachialis muscles 11/26/2024 11:43:56 AM 221 11/26/2024 11:43:56 AM 222 Biceps brachii O:Long head: supraglenoid tubercle and the superior portion of the glenoid labrum. Short head: lateral aspect of the apex of the coracoid process of the scapula. I:Radial tuberosity and the biceptal aponeurosis. In: Musculocutaneous nerve (C5, 6). B/s: Muscular branches from the brachial artery. 11/26/2024 11:43:56 AM 223 11/26/2024 11:43:56 AM 224 Action 1. Flexion of the forearm at the elbow Biceps brachii flexes the elbow with the forearm supinated 2. Assists with flexion of the arm at the shoulder 3. Assists with supination of the forearm 11/26/2024 11:43:56 AM 225 Coracobrachialis O: apex of the coracoid process of the scapula. I:Medial aspect of the mid shaft of the humerus In: Musculocutaneous nerve (C5, 6, 7). B/ s:Muscular branches from the brachial artery. Action 1.Flexion of the arm at the shoulder 2.Assists with adduction of the arm at the shoulder 11/26/2024 11:43:56 AM 226 11/26/2024 11:43:56 AM 227 Brachialis O:Lower half of the anterior aspect of humerus I:Tuberosity and coronoid process of the ulna. In: Musculocutaneous nerve (C5, 6). B/s:Muscular branches from brachial artery and radial recurrent artery from the radial artery. Action Flexion of the forearm at the elbow Flexor carpi radialis will contract during flexion of the elbow against a heavy resistance and pronator teres may also assist. 11/26/2024 11:43:56 AM 228 Triceps brachii: O:long head:Infraglenoid tubercle of the scapula Lateral head:posterior surface of humerus, superior to radial groove Medial head: Posterior surface of humerus ,inferior to radial groove I:Posterior surface of the olecranon process of the ulna. In: Radial nerve (C6, 7,8) B/s:muscularbranches,superiorulnarcollateral, profundal 11/26/2024 11:43:56 AMbrachial arteries(branches of brachial 229 Lateral head of tricepts Long head of triceptis Middle head 11/26/2024 11:43:56 AM 230 Action Chief extensor of the forearm Long head resists dislocation of shoulder important during abduction. 11/26/2024 11:43:56 AM 231 11/26/2024 11:43:56 AM 232 Anconeus O:Posterior surface of the lateral epicondyle of the humerus. I; Lateral aspect of the olecranon, extending to the lateral part of the ulnar body. In: Radial nerve (C7, 8). B/ s:Profunda brachii artery from the brachial artery. Actions Anconeus is a weak extensor of the elbow, stabilizes elbow joint, may abduct ulna during pronation 11/26/2024 11:43:56 AM 233 Anconeus 11/26/2024 11:43:56 AM 234  MUSCLES OF THE FORE ARM Flexor-pronator muscles Superficial layer pronator teres m. Palmaris longus m. Flexor carpi radialis m. Flexor carpi ulnaris m. Intermediate layer flexor digitorum superficialis Deep layer flexor digitorum profundus m flexor policis longus m. pronator quadratus 11/26/2024 11:43:56 AM 235 11/26/2024 11:43:56 AM 236  Pronator teres O:Humeral head: superior portion of the medial epicondyle via the common flexor tendon. Ulnar head: coronoid process of the ulna. I:Lateral aspect of the mid shaft of the radius. In:Median nerve (C6, 7). B/ s:Muscular branches from the ulnar and radial arteries. Action 1. Pronation of the forearm 11/26/2024 11:43:56 AM 237 11/26/2024 11:43:56 AM 238 2. Assists with flexion of the forearm at the elbow. Pronator teres as pronator of the forearm Flexor carpi radialis O:Medial epicondyle of the humerus via the common flexor tendon. I:Base of the second metacarpal. In:Median nerve (C6, 7). B/s:Muscular branches from the radial artery. 11/26/2024 11:43:56 AM 239  Action 1. Flexion of the wrist Flexor digitorum superficialis, flexor digitorum profundus, and flexor pollicis longus assist with flexion of the wrist. 2. Abduction of the wrist. 3. Assists with flexion of the forearm at the elbow. 11/26/2024 11:43:56 AM 240 Palmaris longus Fusiform muscle, may be absent O: medial epicondyle of humerus I:distal ½ of f.retinaculum and apex of palmar aponeurosis. In.: Median nerve Action Flexes hand at wrist joint and tenses palmar aponeurosis. 11/26/2024 11:43:56 AM 241 Flexor carpi ulnaris O;Humeral head: medial epicondyle via the common flexor tendon. Ulnar head: medial aspect of the olecranon and the proximal three- fifths of the dorsal ulnar shaft. I:Pisiform and hamate bones Base of the fifth metacarpal In:Ulnar nerve (C8, T1). 11/26/2024 11:43:56 AM 242 11/26/2024 11:43:56 AM 243 B/s:Muscular branches from the ulnar artery. Action 1. Flexion of the wrist Flexor digitorum superficialis, flexor digitorum profundus, and flexor pollicis longus assist with flexion of the wrist. 2. Ulnar deviation of the wrist. 11/26/2024 11:43:56 AM 244 Flexor digitorum superficialis O:Ulnar head: medial epicondyle of humerus via the common flexor tendon, medial border of the base of the coronoid process of the ulna, and ulnar collateral ligament. Radial head: oblique line of the radius along its supero-anterior border. I:shaft of each middle phalanx of the four digits via a bifurcated tendon. In:Median nerve (C7, 8, T1). B/S:Muscular brs. from ulnar and radial arteries. 11/26/2024 11:43:56 AM 245 11/26/2024 11:43:56 AM 246 Action 1.Flexion of the digits at the proximal interphalangeal joints 2. Assists with flexion of the digits at the metacarpophalangeal joints 3. Assists with flexion of the wrist Flexor pollicis longus and flexor digitorum profundus assist with flexion of the wrist. 11/26/2024 11:43:56 AM 247 Flexor digitorum profundus O:Anteromedial surfaces of the superior three- quarters of the ulna and adjacent interosseous membrane. I: bases of the distal phalanx of the medial four digits (travels through a split in the tendon of flexor digitorum superficialis). In: Medial portion: ulnar nerve (C8, T1). Lateral portion: anterior interosseous branch of median nerve (C8, T1). B/s:Muscular branches and the anterior interosseous artery from the ulnar artery and muscular branches from the radial artery. 11/26/2024 11:43:56 AM 248 11/26/2024 11:43:56 AM 249  Actions 1. Flexion of the digits at the proximal interphalangeal joints 2.Flexion of the digits at the distal interphalangeal joints 3. Assists with flexion of the digits at the metacarpophalangeal joints 4.Assists with flexion of the wrist Flexor pollicis longus and flexor digitorum superficialis also assist with flexion of the wrist. 11/26/2024 11:43:56 AM 250 Flexor policis longus Long flexor of the thumb,lies lateral to FDP O:anterior surface of radius and adjacent interosseous membrane I:base of distal phalanx of thumb In: anterior interosseous nerve, from median nerve Action Flexes the distal phalanx of the thumb Flexes the proximal phalanx and the first metacarpal bone 11/26/2024 11:43:56 AM 251 Pronator quadratus O:Distal one-fourth of the anteromedial surface of the ulna. I:Distal one-fourth of the anterolateral surface of the radius. In: Anterior interosseous branch of the median nerve (C8, T1). B/S:Muscular branches from the radial artery and the anterior interosseous artery from the ulnar artery. Action 1. Pronation of the forearm (Anim) 11/26/2024 11:43:56 AM 252 11/26/2024 11:43:56 AM 253 11/26/2024 11:43:56 AM 254 EXTENSOR MUSCLES OF THE FORE ARM Are in the posterior(extensor –supinator) compartment. All are innervated by branches of radial nerve Are organized in to 3 functional groups 1.Mm. that extend and abduct or adduct the hand at the wrist joint extensor Carpi radialis longus extensor Carpi radialis brevis extensor Carpi ulnaris 2.Mm. that extend the medial 4 digits(extensor digitorium,extensor indicis, extensor digiti minimi 11/26/2024 11:43:56 AM 255 3.Muscles that extend or abduct the thumb abductor policis longus extensor policis longus extensor policis brevis The extensor tendons are held together at the wrist by the extensor retinaculum, which prevents bow stringing of the tendons when the hand is extended at the wrist joint. The tendons are covered by synovial tendon sheaths as they traverse the dorsum of the wrist. 11/26/2024 11:43:56 AM 256 Extensor mm. are organized anatomically in to: Superficial extesnsors ECRB Originated from later. ED epicondyle by comm. EDM Extensor origin ECU Brachioradialis originate from lateral ECR supracondylar ridge 11/26/2024 11:43:56 AM 257  Deep extensors EPL EPB APL EI Supinator 11/26/2024 11:43:56 AM 258 Brachioradialis O:Upper lateral supracondylar ridge of the humerus (between triceps brachii and brachialis). I:Superior aspect of the styloid process and the lateral side of the distal radius. In: Radial nerve (C5, 6). B/s:Radial recurrent artery from the radial artery. Action 1. Flexion of the forearm at the elbow Flexor Carpi radialis will contract during flexion of the elbow against a heavy resistance. 11/26/2024 11:43:56 AM 259 11/26/2024 11:43:56 AM 260 Extensor carpi radialis longus O:Lower lateral supracondylar ridge (below brachioradialis). I:Dorsal surface of the base of the second metacarpal. In:Radial nerve (C5, 6). B/ s;Radial recurrent artery from the radial artery. Actions 1. Extension of the wrist 2. Radial deviation of the wrist. Extensor pollicis brevis and abductor pollicis longus assist with radial deviation of the wrist. 11/26/2024 11:43:56 AM 261 Extensor Carpi radialis brevis O:Lateral epicondyle of the humerus via the common extensor tendon and the radial collateral ligament of the elbow. I:Dorsal surface of the base of the third metacarpal. In:Radial nerve (C6, 7). B/s:Radial recurrent art. from the radial artery Actions 1. Extension of the wrist 2. Radial deviation of the wrist 11/26/2024 11:43:56 AM 262 11/26/2024 11:43:56 AM 263 Extensor digitorum O:Lateral epicondyle of the humerus via the common extensor tendon. I:Main attachment: dorsal aspect of the base of the proximal phalanx of each of the four digits. Central slip: dorsal aspect of the base of the middle phalanx of each of the four digits. Lateral bands: via two slips to the dorsal aspect of the base of distal phalanx of each of the 4 digits. In:Radial nerve (C6, 7, 8). B/s:Post. interosseous artery from the ulnar art. 11/26/2024 11:43:56 AM 264  Actions 1.Extension of the digits at the metacarpophalangeal (mcp) joints 2.Extension of the digits at the proximal interphalangeal joints when mcp joints are flexed 3.Extension of the digits at the distal interphalangeal joints when mcp joints are flexed 4.Assists with extension of the wrist with digits flexed at the metacarpophalangeal joints Extensor digiti minimi and extensor pollicis longus assist with extension of the wrist. 5. Abduction of the digits during extension of the carpometacarpal joints of the digits 11/26/2024 11:43:56 AM 265 Extensor digiti minimi O:Lateral epicondyle of the humerus via the common extensor tendon and the ulnar aspect of extensor digitorum. Is: via two slips to the dorsal surface of the base of the distal phalanx of the fifth digit. In:Radial nerve (C6, 7, 8). B/s:Posterior interosseous artery from the ulnar artery. 11/26/2024 11:43:56 AM 266 Actions 1.Extension of the fifth digit at the proximal interphalangeal joint 2.Extension of the fifth digit at the distal interphalangeal joint 3.Assists with extension of fifth digit at the metacarpophalangeal joint 4.Assists with abduction of the fifth digit at the carpometacarpal joint 5.Assists with extension of the wrist Extensor digitorum and extensor pollicis longus also assist with extension of the wrist. 11/26/2024 11:43:56 AM 267 11/26/2024 11:43:56 AM 268 Extensor carpi ulnaris O:from the common extensor origin I:Tubercles on the medial side of the base of the fifth metacarpal. In:Radial nerve (C6, 7, 8). B/s:Posterior interosseous artery from the ulnar artery. Actions 1. Extension of the wrist Extensor digitorum, extensor digiti minimi, and extensor pollicis longus assist with extension of the wrist. 2. Ulnar deviation 11/26/2024 11:43:56 AM of the wrist 269 Supinator O:Lateral epicondyle of the humerus, the radial collateral ligament, the supinator crest of the ulna, and annular ligaments. I:Proximal portion of the anterolateral surface of the radius. In:Radial nerve (C6, 7, 8). B/s:Radial recurrent artery from the radial artery. Action 1.Supination of the forearm 11/26/2024 11:43:56 AM 270 11/26/2024 11:43:56 AM 271 EXTENSOR INDICIS O:posterior surface of distal third of ulna I:Extensor expantion of second finger In:posterior interosseous nerve(c7,c8),C0ntinuatin of deep branch of radial nerve. Action Extends second finger, helps extend hand at wrist 11/26/2024 11:43:56 AM 272 11/26/2024 11:43:56 AM 273 Abductor pollicis longus O:Posterior surfaces of the ulna and the radius and the interosseous membrane. I:Lateral aspect of the base of the first metacarpal. In:Radial nerve (C6, 7, 8). B/s:Posterior interosseous artery from the ulnar artery. 11/26/2024 11:43:56 AM 274 Actions 1. Radial abduction of the thumb at the trapeziometacarpal joint 2. Extension of the thumb at the carpometacarpal joint 3. Assists with extension of the thumb at the metacarpophalangeal joint 4. Assists with radial deviation of the wrist Extensor pollicis brevis may also assist with radial deviation of the wrist. 11/26/2024 11:43:56 AM 275 Extensor pollicis longus O:Post. surface of the ulna and the i.osseous membrane. I:Distal phalanx of the thumb. In:Radial nerve (C6, 7, 8). B/s:Post. interosseous art. from the ulnar art. Action 1.Extension of thumb at the interphalangeal jt. 2.Assists with extension of the thumb at the mcp joint and assists extension of the wrist 11/26/2024 11:43:56 AM 276 Extensor pollicis brevis O:Post. surface of distal third of the radius and the i.oss. memb. I:proximal phalanx of the thumb. In:Radial nerve (C6, 7, 8). B/s:Post. interosseous artery from the ulnar art. Actions 1. Extension of the thumb at the CMC joint 2. Assists with extension of the thumb at the MCP joint 3. Assists with extension of the wrist 11/26/2024 11:43:56 AM 277 11/26/2024 11:43:56 AM 278 11/26/2024 11:43:56 AM 279  THE HAND The hand is the distal part of the upper limb. It is a sensory and motor instrument capable of a very wide range of activities The activities of the hand can be divided into 3: 1.Power grip 2.Precision handling 3.Pinch 11/26/2024 11:43:56 AM 280 280 11/26/2024 11:43:56 AM 281 281  Power grip Power grip is the forcible motion of the fingers and the thumb acting against the palm The motion transmits force to an object and, in contrast to free motion, is static and isometric. The hand conforms to the shape and size of the object. To do this phalangeal rotation abduction and adduction may be required, e.g. spherical grip, hook grip, disc grip and various kinds of squeezes. 11/26/2024 11:43:56 AM 282 282  Precision handling: Involves a change in position of a handled object either in space or about its own axes. It is dynamic and isotonic and mostly involves two basic modes of handling. 1. Precision rotation – involving the thumb and other fingers that rotate an object about one of its internal axes, e.g. winding a watch. 2. Precision translation – the moving of an object away from or towards the palm, e.g. threading a needle, buttoning a shirt... 11/26/2024 11:43:56 AM 283 283  pinch – Is compression of an object between the thumb and index finger or between the thumb and the two adjacent fingers. it is primarily a static and isometric activity. e.g., handling a tea cup, holding a coin... 11/26/2024 11:43:56 AM 284 284 Muscles of the hand Short mm. of the hand are divided in to 3 groups. Thenar, hypothemar and Intrinsic mm. 1. Thenar muscles These form ball of the thumb which is a fleshy mass on the lateral sides of the palm. To this belong: 1. Abductor pollicis brevis 2. Flexor pollicis brevis 3. Opponens pollicis 4. Adductor 11/26/2024 11:43:56 AM pollicis 285 285  Opponens pollicis Abductor pollicis brevis Flexor policis brevis Adducto r policis 11/26/2024 11:43:56 AM 286 286 These four muscles are arranged in 3 layer. Superficial layer - Abductor pollicis brevis - Superficial part of flexor pollicis brevis Middle layer - Opponens pollicis Deep layer- Deep part of flexor pollicis brevis - Adductor pollicis 11/26/2024 11:43:56 AM 287 287 These muscles arise from the carpal bones and some of them additionally from the flexor retinuculum Inserted to the base of the proximal phalanx of the thumb with few exceptions. Their action corresponds to their names All of them are innervated by median nerve except, those that form the deep layer (adductor pollicis and deep part of flexor pollicis brevis) which are innervated by ulnar nerve. 11/26/2024 11:43:56 AM 288 288 2. Hypothenar muscles (Antithenar) They form the hypothenar eminence or prominence, which is a fleshy mass on the medial side of the palm composed of 4 mm. 1. Palmaris brevis 2. Abductor digiti minimi 3. Flexor digiti minimi brevis 4. opponens digiti minimi All of them are innervated by ulnar nerve. Their action corresponds to their names 11/26/2024 11:43:56 AM 289 289  Abductor digiti minimi Flexor digiti minimi Opponens digiti minimi 11/26/2024 11:43:56 AM 290 290 11/26/2024 11:43:56 AM 291 11/26/2024 11:43:56 AM 292 3. Intrinsic muscles of the hand This group consist of: 1. Lumbricales (4) 3. Dorsal Interosssei (4) 2. Palmar Interossei (3) Lumbricales O- tendon of the FDP. The radial two lumbricales arise by one head from the radial side of the lateral two tendons of F.D.P. The ulnar two lumbricales arise by two heads from the adjacent side of the medial two tendons of F.D.P. 11/26/2024 11:43:56 AM flexor digiturm profoundus 293 293 1st and 2nd 3rd and 4th lumbricales lumbricales(bipen ate) (unipenate) 11/26/2024 11:43:56 AM 294 294 I:Each to the radial surface of the extensor apparatus of the same digits as the tendons of origin. In:First and second lumbricals: median nerve (C8, T1). Third and fourth lumbricals: ulnar nerve (C8, T1). B/ s:Deep palmar arch of the radial artery 11/26/2024 11:43:56 AM 295 295 Action 1. Flexion of the digits at the metacarpophalangeal joints 2. Assists with extension of the digits at the proximal interphalangeal joints 3. Assists with extension of the digits at the distal interphalangeal joints 11/26/2024 11:43:56 AM 296 296 Palmar interossei O:Ulnar aspect of the palmar surfaces of the second metacarpal and radial aspect of the palmar surface of 4th and 5th metacarpals. I:Ulnar aspect of the base of the proximal phalanx and extensor apparatus of the second digit and the radial aspect of the base of the proximal phalanx and extensor apparatus of the fourth and fifth digits. In:Ulnar nerve (C8, T1). B/ s:Deep palmar arch of the radial artery. 11/26/2024 11:43:56 AM 297 297  Palmar interosseous (unipannate) 11/26/2024 11:43:56 AM 298 298  Action 1. Flexion of the digits at the metacarpophalangeal joints 2. Assists with adduction of the digits at the metacarpophalangeal joints 3. Assists with extension of the digits at the proximal interphalangeal joints 4. Assists with extension of the digits at the distal interphalangeal joints 11/26/2024 11:43:56 AM 299 299  11/26/2024 11/26/2024 11:43:56 AM 300 300 Dorsal interossei (of hand) O:Each by two heads, to the adjacent sides of the metacarpals in each inter space. The first lying between the 1st and 2nd , the 2nd between the 2nd and 3rd , the 3rd between the 3rd and the 4th, and the 4th between 4th and 5th metacarpals. I:The base of the proximal phalanx.The 1st dorsal interosseous attaches to the radial side of the thumb, the 2nd attaches to the radial side of the 2nd digit, the 3rd attaches to the ulnar side of the 2nd digit, and the 4th attaches to the ulnar side of the 3rd digit. 11/26/2024 11:43:56 AM 301 301 Dorsal interosseous (bipennate) 11/26/2024 11:43:56 AM 302 302 In:ulnar nerve (C8, T1). B/s:Deep palmar arch of the radial artery. Primary action 1.Flexion of the digits at the MCP joints 2.Assists with abduction of the digits at the MCP jts with axis of rotation running through 3rd digit Extensor digitorum may also assist with abduction of the digits at the MCP joints. 3.Assists with extension of the digits at the proximal interphalangeal joints 4.Assists with extension of the digits at the distal interphalangeal 11/26/2024 11:43:56 AM joints 303 303 11/26/2024 11:43:56 AM 304 304  JOINTS OF THE 11/26/2024 11:43:56 AM UPPER LIMB 305  Joints of the shoulder girdle I. Sternoclavicular joint A. Articulating surfaces Clavicular notch of the sternum Articular facet of the sternal end of the clavicle Articular disc (oval fibro cartilaginous disc) B. Articular capsule - is wide and attached to the margins of the articular surface and to the articular disc 11/26/2024 11:43:56 AM 306 C. Ligaments 1. Anterior and posterior sternoclavicular ligaments –reinforce the joint anteriorly and posteriorly. 2. Interclavicular ligament –strengthen the joint capsule superiorly. 3. Costoclavicular ligament -helps to prevent the upward displacement of the clavicle and dislocation of the sternoclavicular joint. D. Axes - it is a multiaxial saddle joint Functionally ball-and-socket synovial joint. 11/26/2024 11:43:56 AM 307 11/26/2024 11:43:56 AM 308  E. Movements 1. On the sagittal axis - elevation of the shoulder (600) and depression (only 100) of the elevated shoulder. 2. On vertical axis - Forward and backward movement of the shoulder(200 - 00 - 200). 3. On the longitudinal axis - rotation of the clavicle, which is associated with sliding movement of the scapula on the thorax and the movements on the other two axes. 11/26/2024 11:43:56 AM 309  II. Acromioclavicular joint Articulating surfaces(facets) an incomplete articular disc is usually found between the two surfaces. Articular capsule - is wide and attached to the margins of the articular surfaces. Ligaments Acromioclavicular ligament -It reinforces the superior aspect of the articular capsule. 11/26/2024 11:43:56 AM 310 11/26/2024 11:43:56 AM 311 Coracoclavicular ligament: It has two parts: Conoid ligament - the medial inverted shaped part of the coracoclavicular ligament. Trapezoid ligament - is the lateral quadrilateral part of the coracoclavicular ligament The coracoclavicular ligament prevents the upward displacement of the clavicle and dislocation of the acromioclavicular joint. D. Axes similar to SC joint E. Movements 11/26/2024 11:43:56 AM 312 The Shoulder (Glenohumeral) joint Articular surfaces Glenoid cavity of the scapula and head of the humerus. Both the articulating surfaces are covered by hyaline cartilage. The glenoid cavity can receive only 1/4 - 1/3 of the head of the humerus The cavity is widened and slightly deepened by a lip of fibrocartilage the glenoidal labrum.. 11/26/2024 11:43:56 AM 313 11/26/2024 11:43:56 AM 314 Articular capsule - is very wide Attachment superiorly : to outer part of the glenoidal labrum, Inferomedially :to surgical neck and inferolaterally : to anatomical neck of humerus. It is reinforced only anteriorly by the coracohumeral ligament. In the intertubercular sulcus the capsule covers the tendon of the long head of biceps forming the intertubercular synovial sheath. 11/26/2024 11:43:56 AM 315  Ligaments Coracohumeral lig. - extends from coracoid process to greater and lesser tubercles. It reinforces the superior part of the capsule Glenohumeral ligs. (Sup., middle and inf.) they extend between the glenoid labrum and the anatomical neck of the humerus. Transverse humeral ligament -holds the long head of biceps in the groove. Coracoacromial ligament - forms a fibrous arch roofing the shoulder joint. It also prevents the upward dislocation of the humerus 11/26/2024 11:43:56 AM 316 11/26/2024 11:43:56 AM 317 Bursae - 1. Communicating bursae a. Subacromial bursa b. Subcoracoid bursa c. Subtendinous bursa of subscapularis m. 2. Non-communicating bursae a. Subdeltoid bursa b. Subcutaneous acromial bursa The subdeltoid bursa may sometimes communicate with the synovial cavity through the subacromial bursa. 11/26/2024 11:43:56 AM 318 11/26/2024 11:43:56 AM 319 Axes –multiaxial(ball-and-socket) Movements On the sagittal axis - Abduction -Adduction On the transverse axis - Flexion (anteversion) - Extension (Retroversion) 3. On the longitudinal axis Medial rotation Lateral 11/26/2024 11:43:56 AM rotation 320  The movements at the shoulder joint are usually associated with movements of the clavicular joints thereby increasing the range of movement, that is: Abduction - Adduction : 1800 - 00 - 400 Flexion - Extension : 1800 - 00 - 400 Medial rotation - Lateral rotation : The stability of the shoulder joint is assisted muscles forming the rotator cuff( supraspinatus, by the infraspinatus, subscapularis and teres minor muscles) 11/26/2024 11:43:56 AM 321 11/26/2024 11:43:56 AM 322  The shoulder joint is one of the most common sites of dislocation or subluxation in our body. When it occurs the dislocation is usually in a distal direction(inferiorly).. There are three factors that make the shoulder joint the most common site of dislocation (subluxation). The small contact area between the articular surfaces The wide articular capsule The presence of only very 11/26/2024 11:43:56 AM few ligaments. 323  ELBOW JOINT A synovial joint of hinge variety There are three joints in the elbow region, 1, Humeroulnar joint 2, Humeroradial joint 3, Proximal radioulnar joint The three joints have a common capsule & they share a single synovial cavity , due to this they are considered together as a single joint. 11/26/2024 11:43:56 AM 324  Articular Capsule - covers the articulating parts including the olecranon , coronoid & radial fossa of the humerus. It doesn’t cover the epicondyles. - around the neck of the radius it forms an outpocketing called sacciform recess of elbow joint. 11/26/2024 11:43:56 AM 325 11/26/2024 11:43:56 AM 326 11/26/2024 11:43:56 AM 327 - A transverse line passing 2-3cm below the epicondyles indicates the level of humeroulnar & humeroradial joints. Articular surfaces 1, Trochlea of humerus & trochlear notch of ulna. 2, capitulum of humerus & articular fovea of head of radius. 3, Articular circumference of the head of the radius & radial notch of the ulna. 11/26/2024 11:43:56 AM 328 11/26/2024 11:43:56 AM 329 Humeroulnar Joint main joint of the elbow which is hinge in type. ( uniaxial ) formed b/n trochlea of the humerus & trochlear notch of the ulna. Movement - flexion & extension. 11/26/2024 11:43:56 AM 330 11/26/2024 11:43:56 AM 331 11/26/2024 11:43:56 AM 332 Humeroradial Joint - with regard to the articulating surfaces it is ball & socket type of joint. But functionally it is hinge in type. - From an extended position ( called in orthopedics 0 or Zero position ) a flexion of 140 * is possible , Degree of flexion depends on muscle volume of the arm & forearm. 11/26/2024 11:43:56 AM 333 - In the extended arm the tips of olecranon & the two epicondyles lie in a straight line ( Hueter’s line ). During flexion of the arm to 90º they form an equilateral triangle. Most often there is a subcutaneous bursa on the olecranon. This bursa may be inflammed by repeated trauma resulting in olecranon bursitis ( students elbow or miner’s elbow ). 11/26/2024 11:43:56 AM 334 – Relations of elbow joint -Anteriorly - Brachialis , median nerve , brachial aa , tendon of biceps. -Medially- ulnar nerve , flexor carpi ulnaris , common flexor origin. -Posteriorly - triceps & anconeus -Laterally - Supinator , extensor carpi radialis brevis , & other common extensors. 11/26/2024 11:43:56 AM 335 RADIOULNAR JOINTS 1, Proximal-(pivot joint) - Articular surfaces - articular circumference of head of radius - radial notch of ulna Ligaments -radial collateral -annular Articular capsule -similar to elbow joint Movement -pronation & supination 11/26/2024 11:43:56 AM 336  2, Distal radio ulnar - Articular surfaces - ulnar notch of radius - articular circumference of head of ulna. Articular Capsule - Is wide & attached at the boundary b/n the bones & their articular cartilage above & to the margins of the articular disc below. - part of the capsule extends proximally b/n the radius & ulna for about 1-2cm 11/26/2024 11:43:56 AM 337 11/26/2024 11:43:56 AM 338 11/26/2024 11:43:56 AM 339  Ligament - Interosseous membrane connects the interosseous border of radius & ulna. - keeps pressure balance b/n radius & ulna. - prevents friction / rubbing b/n the bones - sometimes referred as middle radioulnar joint - In its upper 1/3 it is strengthened by the oblique cord ( Weitbrecht’s cord , Coopers ligament. 11/26/2024 11:43:56 AM 340  – Axis of movement -Uniaxial pivot joint , axis runs diagonally from the center of the head of radius proximally to the middle part of the head of the ulna distally. – Movements -supination -pronation -The ‘O’ position during pronation & supination movements is when the transverse axis of the forearm lies in sagittal plane. 11/26/2024 11:43:56 AM 341 11/26/2024 11:43:56 AM 342  Applied Anatomy -In cases of forearm fracture POP casts should be applied in a supinated position. 3. RADIOCARPAL JOINT ( Proximal wrist jt ) synovial joint of the ellipsoid variety. Articular surfaces Upper - inferior surface of the lower end of the radius & articular disc of the inferior radioulnar joint. Lower - the three proximal carpal bones; -scaphoid - lunate triquetrium 11/26/2024 11:43:56 AM 343  Articular capsule - Surrounds the joint & is attached above to the lower ends of radius & ulna & below to the proximal row of carpal bones. - Is wide , thin & is strengthened by ligaments in its palmar , dorsal & lateral aspects. Ligaments Anterior ( palmar radiocarpal ) Strong band directed to medially & downwards from radius to lunate bone. 11/26/2024 11:43:56 AM 344  Posterior ( dorsal radiocarpal ) Is weaker than the anterior ligament, is directed downwards & medially to lunate bone. Lateral ( radial collateral ) -Extends from styloid process of the radius to the lateral side of the scaphoid bone. - Medial ( ulnar collateral ) - Extends from styloid process of the ulna to the triquetral & pisiform bones. 11/26/2024 11:43:56 AM 345 Relations - Anterior – long flexor tendons with their synovial sheath & median nerve. - Posterior - extensor tendons of the wrist & fingers with their sheath. - Lateral - radial artery. Blood Supply -Anterior & Posterior carpal arches Nerve Supply -Anterior & posterior interosseous nerves 11/26/2024 11:43:56 AM 346  Movements 1, A transverse radioulnar axis passing through lunate bone. -Palmar & dorsal flexion both for 90* from ‘O’ position 2, A sagittal dorsopalmar axis passing through capitate bone. -Abduction ( radial deviation ) for ~15* -Adduction ( ulnar deviation ) for ~45* from ‘O’ position. flexion is usually combined with adduction & extension with abduction. 11/26/2024 11:43:56 AM 347 MIDCARPAL ( Distal wrist ) JOINT A jt b/n distal & proximal row of carpal bones Articular cavity is S- shaped , due to the downward projection of scaphoid from the proximal row & upward projection of capitate from distal row. Articular capsule attached at the transition b/n bones & their articular cartilage. Axes & movement - as in radiocarpal joint 11/26/2024 11:43:56 AM 348 11/26/2024 11:43:56 AM 349 Movements -Adduction, abduction, opposition, reposition. -Opposition is the combined movement of abduction, flexion, adduction which can be done with in a range of 50-60º. - It is most important joint in the hand , the loss of the thumb carries a function loss of ~25 % in the hand. Muscles involved in the movement of the carpometacarpal joint of the thumb 11/26/2024 11:43:56 AM 350 11/26/2024 11:43:56 AM 351 JOINTS OF THE FINGERS -All the fingers except the thumb contain the ff joints. 1. Metacarpophalangeal joint between the metacarpal and proximal phalanx. 2. Proximal interphalangeal joints - between proximal and middle phalanx. 3. Distal interphalangeal joints - between the middle and distal phalanx 11/26/2024 11:43:56 AM 352 11/26/2024 11:43:56 AM 353  Cubital fossa a triangular hollow area ,anterior to elbow j Boundaries.superiorly ;-line connecting medial & lateral epicondyle.medially :- pronater teres.laterally :-brachioradilis Floor.brachialis & supinator ms.Roof.deep fascia & bicepital aponeurosis ,subcutaneous t 11/26/2024 11:43:56 AM 354 11/26/2024 11:43:56 AM 354 11/26/2024 11:43:56 AM 355 11/26/2024 11:43:56 AM 356  Contents -brachial artery (terminal) -deep accompanying veins -median nerve -biceps brachii tendon -superficially- median cubital vein &medial and lateral antebrachial cutaneous nerve 11/26/2024 11:43:56 AM 357 11/26/2024 11:43:56 AM 357 11/26/2024 11:43:56 AM 358 11/26/2024 11:43:56 AM 359  Signs of single nerve involvement Long thoracic (C5-7) - paralysis of serratus anterior, which causes “winging” of the scapula when the arm is extended and pressed against a fixed object in front of the patient and difficulty of raising the arm above the horizontal plane. Suprascapular nerve (C5 &6) - Paralysis of supra- and infraspinatus muscle leading to subluxtion of the s