Upper Limb Anatomy (PDF)

Musculoskeletal I module (Upper limb)  Scapula *Site: Post. bone of shoulder girdle, covering post. parts of 2nd to 7th ribs. *Type: Flat bone. *General features: 2 Surfaces 3 Borders...

Musculoskeletal I module (Upper limb)  Scapula *Site: Post. bone of shoulder girdle, covering post. parts of 2nd to 7th ribs. *Type: Flat bone. *General features: 2 Surfaces 3 Borders 3 Angles 3 Processes 3 Tubercles 3 Fossae 3 Notches *Anterior *Upper(superior); *Lateral (head *Coracoid; *Supraglenoid; *Supraspinous; *Suprascapular; (ventral) shortest. of scapula); -on lateral end of upper border. above glenoid cavity. above spine. on upper border (costal). carries glenoid -Has tip, upper & lower surfaces, near its lateral end. cavity which is medial & lateral borders. directed laterally *Medial(vertebral); for articulation with *Spine; *Infraglenoid; *Spinoglenoid; *Infraspinous; longest. humerus head -on upper part posterior surface. below glenoid cavity. below spine. between glenoid (shoulder joint). -Has upper & lower surfaces. N.B.: Both are on cavity & lateral Anterior, lateral & posterior (crest posterior surface. border of spine. with upper & lower lips) borders. *Posterior *Lateral; thickest. *Superior; *Acromion; (dorsal). *Tubercle on *Subscapular; *Notch for over 2nd rib. -Continuation of crest of spine. lower lip of on anterior surface. circumflex -Has medial (carries facet for crest of spine scapular A.; *Inferior; lateral end clavicle forming th (near spine root). on dorsal aspect over 7 rib. acromio-clavicular joint) & of lateral border. lateral (continuous with spine at acromial angle) borders. *Identification of side: *Spine; directed posteriorly *Glenoid cavity; directed laterally.  Clavicle *Site: Anterior bone of shoulder girdle, lying horizontally at neck root. It is subcutaneous, extending from sternum medially to shoulder laterally. *Type: Long bone, but differs; its lateral 1/3 has no medullary cavity, formed by membranous ossification & 1st long bone to ossify in embryo, only long horizontal bone. *General features: It has 2 ends & a shaft; Ends Shaft (S-shaped) *Lateral (acromial) end: *Medial 2/3: *Lateral 1/3: Flattened, articulate with facet on Cylindrical 4 surfaces; Flattened. 2 surfaces; medial border acromion forming -Anterior: -Superior: Smooth. acromio-clavicular joint. Convex forwards. -Inferior: Rough. *Medial (sternal) end: -Posterior: 2 borders; Enlarged prismatic, articulates with Concave backwards. -Anterior: manubrium sterni & 1st costal cartilage -Superior: Smooth. Concave forwards & forming sterno-clavicular joint. -Inferior: Rough. present deltoid tubercle. -Posterior: Convex backwards. Inferior surface is rough: *Medially: Rough impression for costo-clavicular ligament. *Laterally: Conoid tubercle (at junction of medial 2/3 & lateral 1/3) & trapezoid line (extending from conoid towards lateral end). *Middle 1/3: Subclavius groove (longitudinal groove) for subclavius insertion. *Identification of side: *Medial end; large *Medial 2/3; Convex forwards. *Superior surface; Smooth. Humerus *Site: Bone of arm. *Type: Long bone. *General features: It has 2 ends & a shaft;  Ends Shaft *Upper end: *3 borders; - Head: A)Anterior: Forms less than half of a sphere, directed medially to Above continuous with lateral lip of articulate with glenoid cavity forming shoulder joint. bicipital groove while below smooth. -2 neck: B)Medial: A)Anatomical; constriction adjoining head. Lower part is sharp (medial supra-condylar ridge). B)Surgical; junction of upper end with shaft, commonest C)Lateral: site of fracture. Lower part is sharp (lateral supra-condylar ridge). -2 tuberosities: A)Lesser; directed forwards. B)Greater; shows 3 impressions (upper, middle & lower) for muscle attachment. N.B.: Bicipital (inter-tubercular) groove; inbetween the 2 tuberosities, having medial & lateral lips & floor inbetween. *Lower end: *3 surfaces; A)Articular part: A)Antero-medial: Shows a nutrient foramen about its middle. *Trochlea; pully shaped, articulates with trochlear notch B)Antero-lateral: of ulna forming part of elbow joint. Shows deltoid tuberosity (V-shaped rough *Capitulum; convex, articulates with radius head forming area) at its middle. another part of elbow joint. C)Posterior: B)Non-articular part: Upper part shows faint ridge while middle *2 epicondyles; shows spiral (radial) groove. A)Medial: Larger ,more prominent & subcutaneous. B)Lateral: Smaller & less prominent. *3 fossae; A)Coronoid: Anteriorly & receives coronoid process of ulna in elbow flexion. B)Radial: Anteriorly & receives radius head in elbow flexion. C)Olecranon: Posteriorly & receives olecranon process of ulna in elbow extension. *Identification of side: *Head; medially *Coronoid & radial fossae, anteriorly. *Carrying angle: Med. margin of trochlea projects downwards more than lat. margin producing angle (15 degrees, more in females) between long axis arm & long axis supinated forearm, when elbow is extended. It allows forearm to swing away from pelvis especially in females with wider pelvis. It disappears when elbow is flexed or forearm is pronated.  Radius & Ulna Bone Radius Ulna *Site Lateral bone of forearm. Medial bone of forearm. *Type Long bone. Long bone. *General Ends: *Upper end: Ends: *Upper end: features -Head: -2 pocesses: 2 ends & a shaft Disc shaped, upper concave surface articulates with capitulum A)Olecranon; above, it projects in olecranon fossa of humerus forming part of elbow joint & circumference articulates with when elbow is extended. radial notch of ulna forming superior radio-ulnar joint. B)Coronoid; below, it projects in coronoid fossa of humerus when elbow is flexed. Its anterior surface shows ulnar tuberosity. -2 notches: -Neck: Constricted part below head. A)Trochlear; anteriorly between olecranon & coronoid processes & receives trochlea forming part of elbow. B)Radial; on lateral surface of coronoid process, articulating with circumference of radius head forming superior radio-ulnar joint. -Radial tuberosity: Anterior smooth & posterior rough. N.B.: Below radial notch, there is supinator fossa which is bounded posteriorly by supinator crest. *Lower end: 5 surfaces; *Lower end: -Head: Rounded, articulating with ulnar notch of radius forming -Anterior: Smooth & concave. -Posterior: Rough & convex, showing dorsal tubercle of lister. inferior radio-ulnar joint. -Lateral: Projects downwards forming styloid process. -Medial: Shows ulnar notch articulating with head ulna forming inferior radio-ulnar joint. -Inferior: Divided into lateral triangular part articulating with -Styloid process: Projection from postero-medial aspect of lower end. scaphoid & medial quadrangular part articulating with lunate.  Radius & Ulna Shaft: *3 borders; Shaft: *3 borders; A)Anterior: A)Anterior: Begins from anterior part of radial tuberosity, its upper part is Begins from medial side of ulnar tuberosity. called anterior oblique line. B)Posterior: B)Posterior: Begins from posterior part of radial tuberosity, its upper part is Begins from apex of triangle on olecranon process back. called posterior oblique line. C)Medial (interosseous). C)Lateral (interosseous) *3 surfaces; *3 surfaces; A)Anterior: Shows a nutrient foramen. A)Anterior: Shows a nutrient foramen. B)Posterior B)Posterior:Shows oblique ridge (above) & vertical ridge(below). C)Lateral: Shows pronator tuberosity at its middle. C)Medial *Anterior surface of lower end; smooth & concave. *Trochlear notch of upper end; anteriorly. *Identification *Styloid process of lower end, laterally. *Radial notch of upper end, laterally. of side Bones of hand 1-Carpal bones: 8 bones arranged in 2 rows; A)Proximal raw: 4 (from lateral to medial); Scaphoid (boat like, has a tubercle), lunate (semilunar), triquetral (pyramidal) & pisiform (sesamoid, smallest of carpal bones). B)Distal raw: 4 (from lateral to medial); Trapezium (has a crest), trapezoid (smaller than trapezium), capitate (largest of carpal bones & 1st to ossify) & hamate (has a hook). N.B.: -Scaphoid is commonest carpal bone to fracture after falling on out- stretched hand, because it receives blood supply through distal part only & in case of fracture at its middle , the proximal fragment is deprived from blood & undergo avascular necrosis. -Anterior dislocation of lunate is common in wrist injuries, as it is broader on anterior than posterior aspect. 2-Metacarpal bones: 5 bones numbered from thumb to little finger. Each has base (articulate with distal carpal bones forming carpo-metacarpal joint), shaft & head (articulate with proximal phalanx of corresponding finger forming metacarpo-phalangeal joint). N.B.: 2 sesamoid bones located anterior to head of 1st metacarpal, are almost constant. 3-Phalanges: 2 in thumb (proximal & distal) & 3 in other fingers (proximal, middle & distal). Each consists of base, shaft & head. Pectoral region *Def.: -Region on upper part of front of chest wall down to the 6th rib -It includes: Skin, superficial fascia (mammary gland), deep (pectoral) fascia & muscles. *Cutaneous nerves of pectoral region: -Supraclavicular nerves (C3,4): From cervical plexus, supplying skin between clavicle & 2nd rib including skin on upper 1/2 deltoid. -Ant. & lat. cutaneous branches of 2nd to 6th intercostals nerves: Supplies skin below 2nd rib. Mammary gland *Shape & type: Modified sweat gland (rudimentary in male). Hemispherical with circular base, nipple & areola on top & axillary tail. *Position: *In superficial fascia of pectoral region at front & side of thorax. Base extends from 2nd rib above to 6th rib below & from sternum medially to midaxillary line (vertical line in middle of axilla, midway between ant. & post. axillary folds) laterally. Base lies on deep fascia covering pectoralis major, serratus ant. & external abdominal oblique aponeurosis. *Axillary tail; tongue like prolongation from gland supero-lat. quadrant, which curves around lower border of pectoralis major to pierce axillary fascia & extends upwards in axilla.  *Structure: Internal structure Covering skin (nipple & areola) th -Consists of 16-20 lobes arranged in radial manner converging -Nipple: Conical projection over 4 towards nipple. Each lobe collects its secretion in lactiferous duct intercostal space, traversed by lacti- which widens deep to areola forming lactiferous sinus then it ferous ducts to open on its summit. narrows again traversing nipple to open on its summit. Nipple position changes after 1st -Lobes are separated into compartments by fibrous septa childbirth & lactation to a variable (cooper's ligament) extending from skin to chest wall deep lower level. fascia. Cancer breast involving these septa may pull on over- -Areola: Circular pigmented skin lying skin leading to nipple retraction. Also it may obstruct skin (containing sebaceous glands) lymphatics causing skin oedema which is pitted by hair follicles surrounds nipple base. In virgins it giving skin orange peel appearance (peau d'orange). is pinkish & becomes darker during -Breast abscess is drained by radial incision to avoid infection 1st pregnancy & never returns again. spread to neighbouring lobes & to minimize damage to radially arranged ducts. N.B.: The gland is small in children & enlarges in females at puberty due to increase in amount of superficial fascia & fat. 2nd enlargement is during 1st pregnancy due to glandular tissue proliferation reaching maximum size during lactation. *Arterial supply: 1-Lat. thoracic branch of 2nd part axillary A.: To breast lat. 1/2. 2-Lat. branches of post. intercostals AA.: To lat. 1/2 (minimally). 3-Perforating branches of internal mammary A. (in 2nd, 3rd & 4th intercostal spaces): To med. 1/2. 4-Pectoral branch of acromio-thoracic of 2nd part axillary A. *Lymphatic drainage: A)Superficial (subareolar) plexus: Under areola, receiving afferents from the gland & sending efferents to deep lymphatic plexus. B)Deep plexus: On deep fascia on which gland lies, receiving afferents from superficial plexus & from gland 4 quadrants, sending efferents as follows; Lat. quadrants Med. quadrants *To pectoral group of axillary L.N.s (mainly). *To para-sternal L.N.s, along internal mammary *To subscapular group of axillary L.N.s (from tail). A. (mainly). *To infra-clavicular L.N.s, its efferents pierce clavi- *To deep plexus opposite side, crossing pectoral fascia to drain in apical group of axillary L.N.s middle line (some). (from upper lat. part). *To sub-diaphragmatic plexus, pierceing *To para-aortic L.N.s (inside thorax), following abdominal wall (from lower med. part). post. intercostals AA. (few from lat. part). N.B.: Axillary L.N.s receive more than 75% of breast lymph while most of remainder enters para-sternal L.Ns. *Clinical importance: Cancer breast & breast abscess (see internal structure). Pectoral fascia: Deep fascia covering pectoralis major muscle. It has 2 extensions; axillary fascia (in axilla floor) & clavipectoral fascia. Clavipectoral fascia *Site: Stong sheet of deep fascia occupying interval between subclavius & pectoralis minor. It lies behind upper part of pectoralis major covering axillary vessels & nerves. *Attachment: -Med.: Attached to 1st & 2nd costal cartilages. -Lat.: Attached to coracoid process, blending with coraco-clavicular ligament. -Above: Splits enclosing subclavius to become attached to subclavius groove. -Below: Splits enclosing pectoralis minor, then continues to axillary fascia (in axilla floor) as suspensory ligament of axilla. Fascia from clavicle to axilla floor is called axillary septum. *Structures piercing: -Acromio-thoracic artery -Cephalic vein. -Lat. pectoral n. -Lymph vessels from infraclavicular to apical group of axillary lymph nodes.  Muscles connecting upper limb with thoracic wall Muscles Muscle Origin Insertion Nerve supply Action Pectoralis -Clavicular head: By a bilaminar tendon into lat. lip Lat. & med. pectoral -Whole muscle: Adduction & med. rotation major Ant. surface of med. of bicipital groove of humerus. nerves. of arm (shoulder joint). 1/2 clavicle. N.B: *Clavicular head forms ant. -Clavicular head: Flexion of arm. -Sternocostal head: lamina, while sternocostal head -Sternocostal head: Extends flexed arm as in of.Ant. surface sternum. forms post. lamina, both laminae swimming, rowing & climbing..Ant. surface upper 6 are continous from below. costal cartilages. *Twisting of tendon lower border.External abdominal forms ant. axillary fold. oblique aponeurosis. pectoral Pectoralis Outer surfaces of 3rd, 4th Upper surface & med. border of Med. pectoral nerve. -Protraction & depression of scapula minor & 5th ribs near their coracoid process of scapula. (shoulder girdle). costal cartilages. -Accessory muscle of forced inspiration. region Subclavius Upper surface of 1st Subclavius groove of clavicle. N. to subclavius Steadies clavicle preventing excessive costochondral junction. (C5, 6). movements of shoulder girdle. Muscle Serratus By 8 digitations from outer Ventral surface of med. border N. to serratus ant. -Powerful protraction of scapula. anterior surfaces of upper 8 ribs, scapula. (long thoracic n. ) -Upward rotation of scapula (abduction of side midway between angles & -1st digit: Sup. angle. (N. of bell) (C5, 6 & 7). from 90-180) by lower 5 digitations. costal cartilages. 1st digitation -2nd, 3rd digits: Whole med. border. -Fixation of scapula to chest wall (if the nerve arises from 1st & 2nd ribs. -Lower 5 digits: Inf. angle. is injured, the muscle will be paralysed & the of chest med. border will project backwards like a wing in pushing against resistance; winging of scapula). -Accessory muscle of forced inspiration.  Muscles connecting upper limb with vertebral column (muscles of back) Muscle Origin Insertion Nerve supply Action Trapezius -Back of skull: Med. 1/3 of sup. V shaped -Motor: -Maintain shoulder level, if paralysed Superficial nuchal line & external occipital -Upper fibres: Post. border Spinal root of accessory n. shoulder drop. (Triangular muscle protuberance. of lat. 1/3 clavicle. (11th cranial n.). -Upper fibres: Elevation of scapula. covering upper -Back of neck: Nuchal ligament -Middle fibres: Med. border -Sensory: C3, 4. -Middle fibres: Retraction of scapula. 1/2 back) & 7th cervical spine. acromion & upper lip of N.B.: It is the only muscle -Upper & lower fibres: Upward -Back of thorax: All thoracic spines crest of spine scapula. in upper limb which is not rotation of scapula. & their supraspinous ligaments. -Lower fibres: Tubercle supplied by brachial plexus. on lower lip of crest of spine scapula. Latissimus -Lower 6 thoracic spines. Floor of bicipital groove of N. to latissimus dorsi -Adduction, extension & med. Dorsi -Thoracolumbar fascia. humerus. ‫(ز‬thoracodorsal n.) rotation of arm (swimming & rowing). (Triangular muscle -Post. part of outer lip of iliac crest. N.B.:It has triple relation -Acting with pectoralis major, covering lower -Outer surfaces of lower 4 ribs. with teres major (1st behind, it pulls trunk upwards as in climbing. layer 1/2 back) -Dorsal aspect of inf. angle then below & finally infront -Accessory muscle of forced expiration scapula. of teres major) forming as in coughing. together post. axillary fold. Levator Transverse processes of upper Dorsal surface of medial -Motor: N. to rhomboids Elevation, retraction & downward Deep scapulae 4 cervical vertebrae. border scapula above root (dorsal scapular n.) (C5). rotation of scapula. of spine. -Sensory: C3, 4. Rhomboideus Nuchal ligament , C7 & T1 spines. Dorsal surface of medial N. to rhomboids Retraction & downward minor border scapula, opposite to (dorsal scapular n.). rotation of scapula. root of spine. layer Rhomboideus T2,3,4,5 spines & their Dorsal surface of medial N. to rhomboids Retraction & downward major supraspinous ligaments. border scapula, below root (dorsal scapular n.). rotation of scapula. of spine.  Muscles of shoulder (scapular) region Muscle Origin Insertion Nerve supply Action Supraspinatus Med. 2/3 of supraspinous fossa. Upper impression of Suprascapular n. (C5,6). -Abduction of arm from 0-15. greater tuberosity of -Stabilization of shoulder joint from above humerus. (rotator muscle cuff). Infraspinatus Med. 2/3 of infraspinous fossa. Middle impression of Suprascapular n. (C5,6). -Adduction & lat. rotation of arm. greater tuberosity of -Stabilization of shoulder joint from behind humerus. (rotator muscle cuff). Teres minor Dorsal surface of upper 2/3 Lower impression of Axillary (circumflex) n. (C5,6). -Adduction & lat. rotation of arm. of lat. border of scapula. greater tuberosity of -Stabilization of shoulder joint from behind humerus. (rotator muscle cuff). Teres major Dorsal surface of lower 1/3 of Med. lip of bicipital Lower subscapular n. (C5,6). Adduction, extension & med. rotation of arm. lat. border of scapula. groove of humerus. subscapularis Med. 2/3 of subscapular fossa. Lesser tuberosity Upper & lower subscapular -Adduction & med. rotation of arm. of humerus. nerves (C5,6). -Stabilization of shoulder joint from infront (rotator muscle cuff). Deltoid V shaped Deltoid tuberosity Axillary (circumflex) n. (C5,6). -Ant. fibres: Flexion & med. rotation of arm. (Thick triangular, -Ant. fibres: Ant. border of lat. 1/3 of humerus -Middle fibres: Abduction of arm from 15-90. forms rounded clavicle. -Post. fibres: Extension & lat. rotation of arm. contour of shoulder) -Middle fibres: Lat. border acromion N.B.: Deltoid paralysis leads to flat shoulder & process. loss of abduction from 15-90. -Post. fibres: Lower lip of crest of spine scapula.  Triangles related to latissimus dorsi muscle Triangle Auscultation triangle Lumbar triangle Boundaries -Above: Lat. border trapezius. -Med.: Lat. border latissimus. -Below: Upper border latissimus. -Lat.: Post. border external abdominal oblique. -Lat.: Lower part med. border of scapula. -Below: Iliac crest. Floor -Rhomboideus major. Internal abdominal oblique & transversus -6th & 7th ribs with space inbetween. abdominis. Clinical Breath sounds are clearly heard here. Might be site of lumbar hernia. importance Rotator muscle cuff (musculo-tendinous cuff of shoulder) Supraspinatus, infraspinatus, teres minor & subscapularis blend with shoulder joint capsule stabilizing head of humerus in glenoid cavity. Quadrangular & triangular spaces Space Quadrangular (lat.) Upper triangular (med.) Lower triangular Boundaries -Above: Teres minor (behind) -Above: Teres minor (behind) -Above: Teres major. & subscapularis (infront). & subscapularis (infront). -Med.: Long head triceps. -Below: Teres major. -Below: Teres major. -Lat.: Lat. head triceps -Med.: Long head triceps. -Lat.: Long head triceps. & shaft of humerus. -Lat.: Surgical neck humerus. Contents -Post. circumflex humeral vessels. Circumflex scapular artery. -Profunda brachii vessels. -Circumflex nerve. -Radial nerve. Relations of deltoid muscle A)Deep relations: *Bones: Upper end of humerus (lesser & greater tuberosities) & scapula (supra & infra- glenoid tubercles, coracoid process). *Muscles: -Subscapularis, supraspinatus, infraspinatus, teres minor & lat. head of triceps. -Long heads of biceps & triceps, pectoralis minor, short head of biceps & coracobrachialis. *Vessels & nerves: Ant. & post. circumflex humeral vessels & circumflex nerve. *Bursa: Subacromial bursa separates deltoid from capsule of shoulder joint & supraspinatus tendon. B)Deltopectoral groove: *Site: Just below clavicle, between pectoralis major & deltoid. *Contents: Deltoid branch of acromio-thoracic artery, cephalic vein (upper part) & deltopectoral lymph nodes.  Axilla *Def., shape & site: Intermuscular space, pyramidal shaped (having apex, base & 4 walls), lying between upper part of side of chest wall & upper part of med. side arm. *Boundaries: a)Apex (cervicoaxillary canal): - Directed upwards & medially, connecting axilla with root of neck, transmitting axillary vessels & nerves from neck to axilla. -Triangular, bounded by: back of clavicle (ant.), upper border of scapula (post.) & outer border of 1st rib (med.). b)Base (floor): -Directed downwards & laterally -Formed of skin (containing hair, sweat & sebaceous glands), superficial fascia & deep (axillary) fascia (receiving attachment of suspensory ligament of axilla). c)Ant. (pectoral) wall: 2 layers: 1-Superficial layer: Pectoralis major. 2-Deep layer (axillary septum): Subclavius, clavipectoral fascia, pectoralis minor & suspensory ligament of axilla (attached to axillary fascia). Ant. axillary fold: Lower border ant. wall; twisted lower border of pectoralis major. d)Post. (subscapular) wall: Subscapularis, teres major & latissimus dorsi. Post. axillary fold: lower border post. wall; teres major & latissimus dorsi. N.B.: Post. fold lies at a slightly lower level than ant. fold because ant wall is slightly shorter than post. wall. e)Med. (costal) wall: Upper 4 ribs & their intercostal muscles, covered by upper part of serratus ant. f)Lat. (humeral) wall: Bicipital groove, hidden by short head biceps & coracobrachialis (narrowest wall). *Contents: 1)Axillary vessels: -Axillary artery & its branches. -Axillary vein & its tributaries. 2)Nerves: -Brachial plexus (cords & branches) -Long thoracic N. -Intercostobrachial N. (lat. cutaneous branch of 2nd thoracic N.) 3)Axillary lymph nodes: 5 groups (ant., post. lat., central & apical). 4)Special contents: - Mammary gland tail -Axillary fat & loose areolar tissue. N.B.: Axillary vessels & brachial plexus run from apex to base of axilla, along lat. wall & nearer to ant. wall.  Brachial plexus *Def.: Net work of spinal nerves , lying partly in neck & partly in axilla, supplying muscles & skin of upper limb. *Formation (Stages) & site: A-Roots: They lie in neck. Formed of ant. rami of lower 4 cervical (C5,6,7,8) & 1st thoracic (T1) nerves.. B-Trunks (3): They lie in neck above clavicle; Uppertrunk: C5,6. -Middle trunk: C7 -lower trunk: C8 & T1. C-Divisions: They lie behind clavicle (at apex of axilla). Each trunk divides into ant. & post. divisions.. D-Cords (3): They lie in axilla; -Post. cord: Union of post. divisions of the 3 trunks. -Lat. cord: Union of ant. divisions of upper & middle trunks -Med. cord: Ant. division of lower trunk. E-Branches: Branches from roots Branches from trunks Branches from cords (upper trunk only) (They lie in axilla) 1-N. to rhomboideus 1-N. to subclavius (C5,6): -Lat. cord (C5,6,7): (dorsal scapular n.) (C5): Descends infront of brachial 1-Lat. pectoral n.: It pierces clavipectoral fascia & It descends on dorsal plexus supplying subclavius. ends by supplying pectoralis major. aspect of med. border 2-Lat. root of median n. scapula supplying levator 3-Musculocutaneous n. (largest branch). scapulae, rhomboideus -Med. cord (all C8 & T1, except ulnar n. C7,8 &T1): minor & major muscles. 1-Med. pectoral n.: It pierces & supplies pectoralis minor to end by supplying pectoralis major. 2-Med. root of median n. 3-Med. cut. n. arm: To skin on lower part of med. side arm. 4- Med. cut. n. forearm: Descends med. to axillary & brachial arteries, then iierces deep fascia at middle arm becoming superficial. It divides into ant. & post. branches, supplying skin on med. side forearm to wrist. 5-Ulnar n. (largest branch). -Post. cord: 1-Upper subscapular n.(C5,6):To upper part 2-N. to serratus ant. 2-Suprascapular N. (C5,6): subscapularis. (long thoracic N.) (N. of *It enters suprascapular 2-lower subscapular n.(C5,6):To lower part Bell) (C5,6,7): It descends foramen to reach supra- subscapularis & teres major. on serratus ant. in mid- spinous fossa, supplying 3-N. to latissimus dorsi (thoracodorsal n.) axillary line supplying it. supraspinatus. (C6,7,8): Descends till inf. angle scapula to supply *It passes through latissimus dorsi. spinoglenoid notch to reach 4-Axillary (circumflex) n. (C5,6) (smaller terminal). infraspinous fossa, supplying 5-Radial n. (C5,6,7,8 & T1) (larger terminal). infraspinatus. It also supplies shoulder joint. N.B.: Branches of lat. & med. cords supply flexor side while branches of post. cord supply extensor side of upper limb.  Axillary ( circumflex) n. Origin & root In axilla, as smaller of the 2 terminal branches of post. cord of brachial plexus (C5,6). value Course & end -In axilla, it lies between 3rd part axillary a. & subscapularis. -It passes backwards below capsule of shoulder joint through quadrangular space, accompanied by post. circumflex humeral a.,to reach back of surgical neck humerus. Branches *Articular: To shoulder joint. *Muscular:.Ant. branch: Continues its course round surgical neck, ends by supplying deltoid..Post. branch: Supplies teres minor, then pierces deep fascia to become upper lat. cut. n. of arm which supplies skin on lower 1/2 of deltoid. Injury Causes: Injury is frequent: 1-Badly adjusted axillary crutch. 2-Downwards dislocation shoulder joint 3-Fracture surgical neck humerus. Results: Motor loss, disability & deformity: -Paralysis of deltoid & teres minor. -Loss of arm abduction from 15-90 degrees. -Flat shoulder (loss of rounded contour) due to deltoid wasting. Sensory loss: Loss of sensation on lower 1/2 of deltoid. Axillary artery *Beginning: At outer border 1st rib as continuation of subclavian A. *Course: It enters axilla through apex & descends along its lateral wall. *End: At lower border teres major by becoming brachial A. *Parts: Pectoralis minor divides it into 3 parts; 1st: Above muscle 2nd: Deep to muscle 3rd: Below muscle (longest). *Relations: Part 1st 2nd 3rd Ant. Clavicular head pectoralis major. - Pectoralis major. -Med. root of median N -Clavipectoral fascia. -Pectoralis minor. Post. -1st digitation serratus ant. - Subscapularis. - Subscapularis. -N. to serratus ant. -Post. cord brachial plexus. -Post. cord branches. -Med. cord brachial plexus Med. - Axillary V. - Axillary V. - Axillary V. -Med. cord brachial plexus. -Med.cord branches. Lat. - Lat. & post. cords brachial plexus. - Lat. cord brachial plexus. - Lat. cord branches. *Branches:  1st part *Sup. thoracic A.: Runs along pectoralis minor upper border to supply thoracic wall upper part, pectoral muscles & breast. branches 2nd part *Lat. thoracic A.: Runs along pectoralis minor lower border reaching chest side to supply serratus ant. In female it gives lat. mammary branches branches supplying gland lat. part. *Acromio-thoracic A.: Pierces clavipectoral fascia & divides into 4 branches: -Acromial : To acromion (anastomosis around shoulder). -Pectoral: Supplies pectoral muscles & breast -Clavicular: Supplies clavicle & subclavius -Deltoid: Supplies pectoralis major & deltoid (anastomosis around shoulder). 3rd part *Ant. circumflex humeral A.: Runs infront of surgical neck, giving ascending branch to shoulder (anastomosis around shoulder) & branches ending by anastomosis with post. circumflex humeral a. (anastomosis around surgical neck). *Post. circumflex humeral A.: Runs backwards reaching surgical neck back, giving descending branch anastomosing with ascending branch of profunda brachii a. & finally anastomoses with ant. circumflex humeral a. (anastomosis around surgical neck). *Subscapular A. (largest branch): Runs along subscapularis lower border & gives circumflex scapular a., then continues as thoraco- dorsal a. reaching & supplying latissimus dorsi (anastomosis around scapula). *Anastomosis shared by axillary a.: Anastomosis around Anastomosis around surgical neck Anastomosis around scapula shoulder joint (Cruciate anastomosis) st st *1 part subclavian a.: *1 part subclavian a.: *1st part subclavian a.(thyro-cervical trunk): Suprascapular a. Descending branch of suprascapular a. -Suprascapular a. -Deep branch pf transverse cervical a. nd *2 part axillary a.: *3rd part axillary a.: rd *3 part axillary a.: Acromial & deltoid branches -Ant. circumflex humeral a. -Subscapular a. -Circumflex scapular a. of acromio-thoracic a. -Post. circumflex humeral a. with its *Descending aorta: Post. intercostals aa. *3rd part axillary a.: ascending & descending branches. Clinical importance: This anastomosis can bypass any obstruction between Ascending branch of ant. *Brachial a.: 1st part subclavian a. & 3rd part axillary a. maintaining blood flow to upper limb. circumflex humeral a. Ascending branch of profunda brachii a. Also it maintains blood flow to body lower half in case of aortic coarctation.  Axillary vein *Beginning: At lower border teres major by union of basilic V. & venae comitantes of brachial A. *Course: It descends on med. side of axillary A. *End: At outer border 1st rib (apex axilla) by becoming subclavian V. *Tributaries: Correspond to axillary A. branches, cephalic V., basilic V. & venae comitantes of brachial A. Deep fascia of arm (brachial fascia) It sends 2 septa (lat. & med.) among arm muscles, separating flexor from extensor muscles & providing additional surfaces for muscles attachment. Septum Lat. intermuscular septum Med. intermuscular septum Attachment Lat. border, lat. supra-condylar ridge Med. border, med. supra-condylar ridge & & lat. epicondyle. med. epicondyle. Muscles of front arm (Flexor group) Muscle Origin Insertion N. supply Action Biceps brachii -Long head: -Bicipital tendon: Musculo- -Flexion of elbow joint. Supraglenoid tubercle Radial tuberosity cutaneous N. -Powerful forearm by a long tendon (post. rough part). supination (when (intracapsular, -Bicipital elbow is flexed). extrasynovial). aponeurosis: -Flexion of shoulder It leaves capsule to From bicipital tendon, joint (short head). descend in bicipital descending med. to -Stabilization of groove where it is blend with deep fascia shoulder joint from retained by transverse in cubital fossa roof. above (long head). humeral ligament. -Short head: Tip of coracoid process, in common with coraco- brachialis. Coraco- Tip of coracoid Middle of med. border Musculo- Flexion & adduction brachialis process, in common humerus. cutaneous N. of arm. with short head biceps. Brachialis -Front of lower 1/2 Ant. surface of coronoid Musculo- Powerful elbow shaft of humerus. process & ulnar tuberosity. cutaneous & flexion. -Front of med. & lat. radial (small intermuscular septa. lat. part) NN.  Musculocutaneous n. Origin & In axilla, from lat. cord of brachial plexus (C5,6,7). root value Course -It descends lat. to 3rd part axillary a. & upper part brachial a. & end -It pierces coracobrachialis , then it passes between biceps & brachialis. -One inch above elbow, lat. to biceps tendon, it pierces deep fascia to become lat. cut. n. forearm. Branches -Muscular: Biceps, brachialis (except small lat. part) & coracobrachialis. -Sensory: Lat. cut. n. forearm: Continuation of musculocutaneous n., it divides into ant. & post. branches, supplying skin on lat. side forearm to wrist & skin on upper part of thumb ball. Brachial artery *Beginning: At lower border teres major as continuation of axillary A. *Course: Its upper part descends on med. side arm then its lower part descends infront of arm passing midway between med. & lat. epicondyles to enter cubital fossa. *End: 1 cm below elbow at level of radius neck by dividing into radial & ulnar terminal branches. *Relations: Ant. Post. Med. Lat. Skin & fascia (in upper part), Long & med. Ulnar N. & basilic V. (in Median N., biceps & coraco- median N. cross it from lat. to heads triceps, upper part), median N. brachialis (in upper part), med. (in middle part) & bicipitial coracobrachialis (in lower part). biceps tendon (in lower part). aponeurosis (in lower part). & brachialis N.B.: 1-Brachial A. is superficial throughout its course (covered by skin & fascia), which makes it easily accessible 2-Median N. has triple relation to brachial a. (lat., then crosses it at level of coracobrachilis insertion & finally becomes med.) *Branches:  Branch Profunda brachii Nutrient Sup. ulnar collateral Inf. ulnar collateral Radial & ulnar *Origin: Largest & highest branch, from postero-med. Arises at middle Arises at middle of Arises 5 cm above elbow, aspect of brachial A. near its beginning. of arm & enters arm, pierces med. divides into; *Course: Accompanied by radial N. it passes backwards nutrient foramen septum with ulnar through lower triangular space, reaching spiral groove near coraco- N., reaching back *Ant. branch; reaching where it passes between lat. & med. heads triceps. brachialis of med. epicondyle front of med. epicondyle *Branches: insertion. anastomosing with post. ulnar anastomosing with ant. 1-Muscular : To triceps 2-Nutrient : To humerus. ulnar recurrent A. recurrent A. 3-Ascending: Anastomoses with descending branch of (anastomosis (anastomosis around post. circumflex humeral A. on back of surgical neck elbow). around elbow) (cruciate anastomosis). 4-Ant. descending terminal (radial collateral): Muscular *Post. branch; pierces Pierces lat. septum with radial N., reaching front of lat. Supply biceps, med. septum to reach back epicondyle anastomosing with radial recurrent A. brachialis & of med. epicondyle, coracobrachialis anastomosing with sup. ulnar (anastomosis around elbow). 5-Post. descending terminal (middle collateral): collateral & post. ulnar recurrent AA. (anastomosis Reaches back of lat. epicondyle anastomosing with post. around elbow). interosseous recurrent (anastomosis around elbow). *Anastomosis around elbow: Anastomosis Around medial epicondyle Around lateral epicondyle Transverse anastomosis Front *Ant. branch of inf. ulnar collateral (brachial A.). *Radial collateral (profunda brachii A.). *Inf. ulnar collateral (brachial A.). *Ant. ulnar recurrent (ulnar A.). *Radial recurrent (radial A.). *Middle collateral (profunda Back *Sup. ulnar collateral (brachial A.). *Middle collateral (profunda brachii A.). brachii A.). *Post. branch of inf. ulnar collateral (brachial A.). *Post. interosseous recurrent of post..*Post. ulnar recurrent (ulnar A.). interosseous (ulnar A.).  Muscles of back arm (extensor group) Muscle Origin Insertion N. supply Action Triceps -Long head: *Upper surface Radial n. (in -Powerful elbow Infraglenoid tubercle. olecranon process. axilla to long extension. -Lat. head: Upper lip of *Few fibers & med. heads, -Articularis cubiti pulls spiral groove on back of (articularis cubiti) in spiral groove back of elbow capsule humers. from deep surface to lat. & med. up during elbow -Med. head.: Back of of lower part heads). extension, preventing humerus below spiral triceps insert in its insinuation inside. groove, back of med. & back of elbow lat. intermuscular septa. joint capsule. Radial n. Origin, In axilla, as larger of the 2 terminal branches of post. cord of brachial plexus (C5,6,7,8 & T1). root value Course -In axilla: It descends between 3rd part of axillary a. & post. wall of axilla. & end -In arm:.In upper 1/3 arm; it descends between upper part brachial a. & long head of triceps..In middle 1/3 arm; it passes backwards between long & med. heads of triceps to reach spiral groove, where it runs downwards & laterally between lat. & med. heads of triceps, accompanied by profunda brachii A.. In lower 1/3 arm; it pierces lat. intermuscular septum accompanied by radial collateral A., reaching front arm where it descends between brachialis & brachioradialis muscles. -In cubital fossa: It enters cubital fossa, where it ends infront of lat. epicondyle by giving a deep branch called post. interosseous N. (mainly motor) & then radial N. continues as superficial radial n. (mainly sensory). Branches In axilla In spiral groove In lower 1/3 arm.Muscular: Long &.Muscular: Lat. & med. heads of.Muscular: Small lat. part of med. heads of triceps. triceps & anconeus. brachialis, brachioradialis &.Cutaneous:.Cutaneous: extensor carpi radialis longus. Post. cut. n. of arm: -Lower lat. cut. n. of arm: To Terminals To skin on back of arm skin on lower 1/2 of lat. side arm. Ends by giving post. interosseous (from deltoid tuberosity -Post. cut. n. of forearm: To skin N. & then radial N. continues as to elbow). on back of forearm down to wrist. superficial radial n.  Deep fascia of forearm (antebrachial fascia) Thicker post. than ant., with 3 sites of thickening: -Strengthened by bicipital aponeurosis. -Along ulna post. border forming an aponeurosis & giving origin to; Flexor carpi ulnaris, flexor digitorum profundus & extensor carpi ulnaris. -In wrist region forming flexor retinaculum (infront) & extensor retinaculum (behind). Muscles of front forearm (Flexors) A- Superficial flexors General rules: -Common flexor origin: Front of med. epicondyle humerus -Common insertion: Palmar aspect of hand except pronator teres. -Common N.: Median n., except flexor carpi ulnaris (ulnar n.) -Common action: Flexion of wrist (except pronator teres) & weak flexion of elbow. Muscle Origin Insertion N. supply Action PRONATOR TERES -Humeral head (larger & more Pronator tuberosity of radius. Median N. -Weak elbow flexion. superficial): Common flexor origin & lower N.B.: Median N. passes between the 2 heads -Powerful pronation forearm. part med. supracondylar ridge. while ulnar A. passes deep to the 2 heads. -Ulnar head (smaller & deeper): Med. side coronoid process of ulna. FLEXOR CARPI Common flexor origin. Palmar aspect of bases of 2nd & 3rd metacarpals. Median N. -Weak elbow flexion. RADIALIS N.B.: Its tendon passes in a special tunnel, -Flexion & abduction wrist through lat. part of flexor retinaculum. (hand). PALMARIS LONGUS Common flexor origin. Apex of palmar aponeurosis. Median N. -Weak elbow & wrist flexion. (slender with long N.B.: Its tendon passes superficial to flexor retinaculum. -Makes palmar aponeurosis tendon, may be absent) tense, giving more protection. FLEXOR CARPI -Humeral head (small): Common flexor origin. Pisiform bone. Ulnar N. -Weak elbow flexion. ULNARIS -Ulnar head: -Med. side of olecranon N.B.: Between its heads passes ulnar N. (reaching -Flexion & adduction wrist. process of ulna. front of forearm). -Upper 2/3 post. border ulna (by aponeurosis).  FLEXOR -Humero-ulnar head: Common flexor It divides into 4 tendons passing deep to flexor Median N. -Elbow & wrist flexion. DIGITORUM origin & med. side coronoid process of ulna. retinaculum. each tendon splits at proximal -Flexion of proximal phalanges SUPERFICIALIS -Radial head: Ant. oblique line radius. phalanx into 2 slips, inserted into sides of shaft (metacarophalangeal joints) & (SUBLIMIS) of middle phalanx of each of med. 4 fingers. middle phalanges (proximal inter- phalngeal joints) of med. 4 fingers. B- Deep flexors General rules: -Common origin: Front of interosseous membrane, except pronator quadratus. -Common insertion: All tendons pass deep to flexor retinaculum, to be inserted in palmar aspect hand, except pronator quadratus. -Common n. supply: Ant. interosseous branch of median n., except med. 1/2 of flexor digitorum profundus (ulnar n.) -Common action: Flexion of wrist , except pronator quadratus. Muscle Origin Insertion Nerve supply Action FLEXOR -Upper 2/3 of front shaft of radius, Its tendon passes through carpal tunnel, deep to flexor retinaculum to Ant. interosseous N. -Flexion wrist. pollicis below ant. oblique line. insert in palmar aspect of base of terminal phalanx of thumb. -Flexion all joints longus -Front interosseous membrane. N.B.: Its tendon is surrounded by radial bursa. thumb. FLEXOR -Upper 3/4 of ant. & med. surfaces It divides into 4 tendons which pass through carpal tunnel, deep -Lat. 1/2: Ant. -Flexion wrist. DIGITORUM shaft of ulna. to flexor retinaculum. Each tendon passes in tunnel between the interosseous N. -Flexion all joints profundus -Front interosseous membrane. 2 slips of each tendon of flexor digitorum superficialis, to be inserted -Med. 1/2: Ulnar N. med. 4 fingers. -Upper 2/3 post. border ulna (by aponeurosis) into base of terminal phalanx of each of med. 4 fingers. N.B.: The 8 tendons of superficialis & profundus are surrounded by ulnar bursa. PRONATOR Oblique ridge on lower 1/4 of front Lower 1/4 of ant. & med. surfaces of shaft of radius. Ant. interosseous N. Pronation forearm quadratus shaft of ulna. (radioulnar joints).  Cubital fossa *Def, shape & site: Intermuscular space, inverted triangular shaped, lying infront of elbow & occupies upper 1/3 of front of forearm. *Boundaries: -Above (base): Transverse imaginary line between the 2 epicondyles. -Med.: Pronator teres -Lat.: Brachioradialis -Below (apex): Meeting of brachioradialis overlapping pronator teres. *Floor: -Med.: Brachialis - Lat.: Supinator. *Roof: A-Skin. B-Superficial fascia; containing: 1-Basilic vein 2-Cephalic vein 3-Median cubital vein 4- Ant. branch of med. cut. nerve forearm. 5 -Ant. branch of lat. cut. nerve forearm 6-Supratrochlear L.N.s (in upper med. part of roof). C-Deep fascia: Reinforced by bicipital aponeurosis (separates median cubital v. superficially from brachial a. & median n. deeply). *Contents (from med. to lat.): 1-Median N. (leaves fossa between 2 heads of pronator teres). 2-End of brachial A. (in middle of fossa) & beginning of radial (leaves fossa through apex) & ulnar (leaves fossa deep to the 2 heads of pronator teres) arteries. 3-Tendon of biceps (inserted in post. part of radial tuberosity). 4-Radial N. & beginning of its post. interosseous branch (leaves fossa by piercing supinator).  Hand Deep fascia of palm (Consists of 3 parts) A)Lat.: Thin & covers thenar eminence B)Med.: Thin & covers hypothenar eminence. C)Central (palmar aponeurosis): Thick & covers intermediate compartment. Palmar aponeurosis *Def.: Central part of deep fascia of palm (strongest & thickest part). *Function: Protection of underlying tendons, vessels & nerves. *Shape: Triangular, having; *Apex (above): Fused with flexor retinaculum & receives Palmaris longus tendon. *Base: Divides into 4 slips, each becomes continuous with fibrous flexor sheath at root of each of med. 4 fingers. *Lat. & med. margins: Continue with deep fascia covering thenar & hypothenar eminences respectively. *Fibrous septa: A)Lat.: From the aponeurosis lat. margin to 1st metacarpal bone. B)Med.: From the aponeurosis med. margin to 5th metacarpal bone. C)Intermediate: From the aponeurosis deep surface near its lat. margin to 3rd metacarpal bone. Muscles of hand Lat. muscles Med. muscles Intermediate muscles A-Muscles thenar A-Muscles hypothenar A-Lumbricals (4 muscles): eminence: eminence: *Origin: -Lat. 2; each arise from lat. -Common origin: From lat. -Common origin: From med. side of corresponding lat. tendon of flexor side of flexor retinaculum. side of flexor retinaculum. digitorum profundus. -Common N. supply: Median -Common N. supply: Deep -Med. 2; each arise from adjacent sides of N. (recurrent muscular branch). branch of ulnar N. med. 3 tendons of flexor digitorum profundus.  *Insertion: Each turns backwards around 1-Abductor pollicis 1-Abductor digiti minimi; metacarpo-phalangeal joint to join brevis: *Lat. side of base of *Med. side of base of proximal extensor expansion of each of med. 4 proximal phalanx of thumb. phalanx of little finger. fingers & finally become inserted into *Abduction thumb (carpo- *Abduction little finger (metacarpo- distal phalanx. metacarpal joint). phalangeal joint). *N. supply: -Lat. 2: Median N. 2-Flexor pollicis brevis: 2-Flexor digiti minimi: -Med. 2: Deep branch of ulnar N. *Lat. side of base of proximal *Med. side of base of proximal *Action: Writing position (flexion of phalanx of thumb. phalanx of little finger. metacarpo-phalangeal & extension of *Flexion thumb (carpo-metacarpal *Flexion little finger (metacarpo- interphalangeal joints) of med. 4 fingers. & metacarpo-phalangeal joints). phalangeal joint). 3-Opponens pollicis: 3-Opponens digiti minimi: *Lat. side of shaft of 1st *Med. side of shaft of 5th metacarpal bone. metacarpal bone. *Opposition (flexion & med. *Opposition of little finger rotation) thumb (carpo- against thumb. metacarpal joint). B-Adductor pollicis: B-palmaris brevis; B-Interossei: *Origin: -Oblique head; bases *Origin: Flexor retinaculum & 1-Four palmar: of 2nd & 3rd metacarpals. palmar aponeurosis. st nd *Origin: From palmar surface of 1 , 2 , -Transverse head; shaft of 3rd *Insertion: Skin on med. side palm. 4th & 5th metacarpals. metacarpal. *N. supply: Superficial branch of *Insertion: -1st; Med. side of base of *Insertion: Med. side of base of ulnar N. proximal phalanx of thumb. proximal phalanx of thumb. *Action: Wrinkles skin on med. side -2nd, 3rd & 4th; Each turns backwards *N. supply: Deep branch of hand to provide a firm hand grip. around metacarpo-phalangeal joint to join ulnar N. extensor expansion of index, ring & little *Action: Adduction thumb fingers & finally become inserted into (carpo-metacarpal joint). distal phalanx. *N. supply: Deep branch of ulnar N. *Action: -Adduction of thumb, index, ring & little fingers. -Writing position. 2-Four dorsal: *Origin: Each arises from adjacent sides of the 2 metacarpal bones between which it lies. *Insertion: Each turns backwards around metacarpo-phalangeal joint to join extensor expansion of index, middle (receives 2 dorsal interossei) & ring fingers , finally become inserted into distal phalanx. *N. supply: Deep branch ulnar N. *Action: -Abduction of index, middle & ring fingers. -Writing position.  Fascial spaces of hand Space Mid palmar Thenar Boundaries *Lat.: Intermediate palmar septum. *Lat.: Lat. palmar septum. *Med.: Med. palmar septum. *Med.: Intermediate palmar septum. *Ventrally: Palmar aponeurosis. *Ventrally: Palmar aponeurosis. *Dorsally: 3rd, 4th & 5th metacarpals with *Dorsally: Transverse head of related interossei. adductor pollicis with covering fascia. Contents *Long flexor tendons of flexor digitorum *Long flexor tendons of index & superficialis & profundus of 3rd, 4th & 5th fingers. thumb fingers. *2nd, 3rd & 4th lumbricals (attached to previous *1st lumbrical (related to index finger). tendons of profundus). *Digital vessels & nerves to med. 3 1/2 fingers. *Digital vessels & nerves to lat. 1 1/2 fingers. Communications *Distally: With webs between med. 4 fingers. *Distally: With web of thumb. *Proximally: With space deep to common *Proximally: With space deep to common synovial sheath in carpal tunnel. synovial sheath in carpal tunnel. N.B.: Space of parona: Space between flexor tendons of forearm (ant.) & pronator quadratus (post.). It is continuous with deep palmar spaces through carpal tunnel behind long flexor tendons. Infection can extend from parona space to palmar spaces & vice versa. Superficial distal pulp space of finger -Pulp space of distal phalanx (at finger tip). It is tightly packed with small lobules of subcutaneous fat separated by fibrous septa, passing from skin to periosteum of distal phalanx. When inflamed it becomes painful due to pus entrapment & compresses on nerves. -Blood vessels of shaft & head (not base) of distal phalanx traverse pulp space. Severe infection may result in thrombosis of shaft & head of distal phalanx & their death (base is spared).  Fibrous flexor sheaths *Def.: Deep fascia on finger ant. surface, which is thickened to hold flexor tendons in contact with ant. surfaces of phalanges during fingers flexion. *Attachment: -Proximal end: Continuous with a slip of palmar aponeurosis. -Distal end: Attached to ant. surface of distal phalanx beyond insertion of flexor digitorum profundus tendon. -The sheath with the phalanx form canal for flexor tendons & their synovial sheaths. At each finger crease skin is attached to fibrous flexor sheath, so pulp over each phalanx is a separate space & infection can spread between pulps along neurovascular digital bundle. Synovial sheaths Common flexor sheath Flexor pollicis sheath Digital synovial sheaths (Ulnar bursa) (Radial bursa) (Digital bursae) -For 8 tendons of superficialis & -For tendon of flexor pollicis -They enclose flexor tendons of each of profundus passing through longus passing through med. 4 fingers in digital canals made of carpal tunnel. carpal tunnel. fibrous flexor sheath & phalanges. -It has a visceral layer applied to -Proximally it extends in fore- -Proximally they extend to heads of tendon & a parietal layer lining arm for 1 inch above flexor metacarpals (except little finger which the tunnel (tendons invaginate retinaculum, while distally it is continuous with ulnar bursa), while sheath from lat. side). extends to muscle insertion. distally they extend to tendons insertion -Proximally it extends in fore- N.B.: Radial & ulnar bursae arm for 1 inch above flexor retinaculum, usually communicate in while distally it ends opposite carpal tunnel. middle of metacarpal bones (except at med. side which becomes continuous with little finger sheath). N.B.: *The 2 layers of sheath are separated by very narrow space with minimal amount of synovial fluid. *Sheaths of index, middle & ring fingers are separated from ulnar bursa by 1-3 cm. Infection of these fingers sheaths remain localized to them, while infection of thumb & little fingers may extend to palm, carpal tunnel & forearm through radial & ulnar bursae. *Flexor carpi radialis tendon has its own synovial sheath in a special tunnel on trapezium.  Median & ulnar nerves Nerve Median n. Ulnar n. Origin In axilla, by 2 roots: Med. root from med. cord & lat. root from lat. cord of In axilla, from med. cord of brachial plexus (C7,8 & T1). & brachial plexus (C5,6,7,8 & T1). root N.B.: Med. root crosses infront of axillary A. to join lat root. N.B.: Fibers C7 reach ulnar n.; lat. cord in axilla or median n. in forearm. value Course -In axilla: It descends lat. to 3rd part of axillary A. -In axilla: It descends med. to 3rd part of axillary A. & end -In arm: -In arm:.In upper 1/2 arm; it descends lat. to upper 1/2 brachial A..In upper 1/2 arm; it descends med. to upper 1/2 brachial A..In middle arm (opposite insertion coracobrachialis); it crosses brachial A..In middle arm (opposite insertion coracobrachialis); it passes from lat. to med. side (either infront or behind A.). backwards piercing med. intermuscular septum (accompanied by sup. ulnar collateral A.) to reach post. compartment arm..In lower 1/2 arm; it descends med. to lower 1/2 brachial A. on brachialis..In lower 1/2 arm; it descends in post. compartment arm on med. head triceps. -In cubital fossa: -At elbow:. It descends med. to lower part of brachial A. & upper part of ulnar A., being. It passes behind med. epicondyle. separated from median cubital V. by bicipital aponeurosis..It leaves cubital fossa & enters forearm by passing between 2 heads of.It enters forearm by passing between 2 heads of flexor carpi ulnaris. pronator teres, being separated from ulnar A. by deep head pronator teres. -In forearm: -In forearm:.It descends in middle of front forearm, between flexor digitorum superficialis &.It descends on med. side of front forearm, between flexor carpi ulnaris profundus. & med. 1/2 flexor digitorum profundus..Above wrist, it becomes superficial, between tendons of flexor carpi radialis.Above wrist, it becomes superficial, between tendons of flexor carpi (lat.) & flexor digitorum superficialis (med.). ulnaris (med.) & flexor digitorum superficialis (lat.) -At wrist: It enters palm by passing through carpal tunnel, deep to flexor -At wrist: It passes superficial to flexor retinaculum, where it ends by retinaculum, where it ends by dividing into med. & lat. terminal branches. dividing into superficial & deep terminal branches.  Median & ulnar nerves Branches -In axilla & arm: No branches. -In axilla & arm: No branches. -In forearm: -In forearm;.Muscular (in cubital fossa): Pronator teres, flexor carpi radialis, Palmaris.Muscular: Flexor carpi ulnaris & med. 1/2 flexor digitorum profundus. longus & flexor digitorum superficialis..Articular: (in cubital fossa): Elbow joint..Articular: Elbow joint..Ant. interosseous n.: -It descends infront of interosseous membrane.Cutaneous: (accompanied by ant. interosseous A.), between flexor pollicis longus (lat.) & -Palmar cut. n.: It passes superficial to flexor retinaculum. It flexor digitorum profundus (med.), then it disappears deep to pronator supplies skin of med. 1/3 palm. quadrates to end by supplying inf. radio-ulnar & wrist joints. -It supplies flexor pollicis longus, lat. 1/2 flexor digitorum profundus & pronator quadrates..Palmar cutaneous n.: It arises 1 inch above wrist, it passes superficial to -Dorsal cut. n.: It reaches dorsum hand, where it divides into 2 flexor retinaculum. It supplies skin of lat. 2/3 palm, except proximal part dorsal digital branches. It supplies skin of dorsal aspect med. 1/3 hand & othenar eminence (supplied by lat. cut n. of forearm). med. 1 & 1/2 fingers. -In palm: -In palm:.Lat. terminal branch: -It gives a recurrent branch suppling thenar eminence.Superficial terminal branch: Supplies palmaris brevis, then divides into 2 muscles (abductor pollicis brevis, flexor pollicis brevis & opponens pollicis). palmar digital branches, supplying skin of palmar aspect med. 1 & 1/2 fingers. -It then divides into 3 palmar digital branches; 2 for skin of palmar aspect of both sides thumb, one for skin of palmar aspect of lat. side index & 1st lumbrical..Deep terminal branch:-It dips between abductor & flexor digiti.Med. terminal branch: It divides into 2 branches; -1st branch: Supplies 2nd lumbrical, then divides into 2 palmar digital branches, minimi, then it pierces opponens digiti minimi (accompanied by deep supplying skin of palmar aspect of adjacent sides of index & middle fingers. palmar branch of ulnar A.) & curves lat. in concavity of deep palmar -2nd branch: Divides into 2 palmar digital branches, supplying skin of palmar arch to end in adductor pollicis. aspect of adjacent sides of middle& ring fingers. -It supplies hypothenar muscles (abductor, flexor & opponens digiti N.B.: The palmar digital branches supplies the palmar aspects & distal minimi), 3rd & 4th lumbricals, interossei (4 palmar & 4 dorsal), adductor halves of dorsal aspects of lat. 3 & 1/2 fingers. pollicis & may also supply flexor pollicis brevis. -It also gives articular branches to wrist & metacarpo-phalangeal joints.  Median & ulnar nerves Injury A-Above elbow: Supracondylar fracture humerus. A-At elbow: -Fracture med. epicondyle, dislocation or compression elbow joint. B-Pronator syndrome: Median N. entrapment caused by N. B-Cubital tunnel syndrome: Ulnar N. compression in compressio n between 2 heads of pronator teres due to trauma, cubital tunnel (tendinous arch connecting the 2 heads of muscular hypertrophy or fibrous bands. flexor carpi ulnaris). Results: Results:. Motor loss, disability & deformity:. Motor loss, disability & deformity: 1-Supination of forearm (paralysis of pronator teres & quadrates). 1 –Radial deviation wrist (paralysis of flexor capi ulnaris). 2-Weak flexion wrist & ulnar deviation (paralysis of muscles front 2- Abduction thumb (paralysis of adductor pollicis). Patient is unable to of forearm, except flexor capi ulnaris & med. 1/2 of flexor digitorum grip piece of paper between thumb & index. profundus). 3-Loss of fingers adduction & abduction (paralysis of interossei). 3-Extension index & middle fingers (paralysis of flexor digitorum Patient is unable to grip piece of paper between fingers. superficialis & lat. 1/2 of profundus). When patient tries to make a 4- Claw hand (patient cannot put hand in writing position, due to fist, index & middle remain straight (pointing fingers). paralysis of med. 2 lumbricals & interossei). There will be extension 4-Loss thumb flexion (paralysis of flexor pollicis longus & brevis). metacarpo-phalangeal joints & equal semiflexion interphalangeal 5-Loss thumb opposition with lat. rotation (paralysis opponens pollicis). joints med. 4 fingers (lat. 2 lumbricals are intact & med. 1/2 of 6- Monkey (Ape) hand: Adduction thumb (paralysis abductor profundus is paralysed). pollicis brevis)..Late trophic changes: Wasting thenar muscles & flat thenar eminence..Late trophic changes: Wasting hypothenar muscles & flat hypothenar eminence , hollowing between metacarpals on hand dorsum (paralysis interossei)..Sensory loss: Loss of sensation from lat. 2/3 palm (except.Sensory loss: Loss of sensation from palmar & dorsal aspects of med. proximal part thenar eminence), palmar aspects & distal halves of 1/3 hand & med. 1 & 1/2 fingers. dorsal aspects lat. 3 & 1/2 fingers.  Median & ulnar nerves C-At wrist: Cut or stab wounds. C-At wrist: Cut or stab wounds. 2- Carpal tunnel syndrome (compression of median n. in carpal tunnel by lunate dislocation, carpal bone osteophytes, arthritic changes of intercarpal joints, inflammation of flexor synovial sheaths or fluid accumulation). Results: Results:.Motor loss ,disability & deformity: Adduction thumb (monkey.Motor loss ,disability & deformity: hand) & loss thumb opposition with lat. rotation (paralysis of 1- Abduction thumb (paralysis of adductor pollicis). Patient is unable to abductor pollicis brevis & opponens pollicis). grip piece of paper between thumb & index. 2-Loss of fingers adduction & abduction (paralysis of interossei). Patient is unable to grip piece of paper between fingers. 3- Partial claw hand, which is more apparent than that occurring in ulnar n. injury at elbow, because of marked flexion of med. 2 fingers (med. 1/2 of flexor digitorum profundus is intact)..Late trophic changes: Wasting hypothenar muscles & flat.Late trophic changes: Wasting thenar muscles & flat thenar eminence. hypothenar eminence , hollowing between metacarpals on hand dorsum (paralysis of interossei)..Sensory loss:.Sensory loss: Loss of sensation from palmar aspect of - If the cause is cut wrist there will be loss of sensation from palmar med. 1 & 1/2 fingers. If palmar cut. branch is involved, there aspects & distal halves of dorsal aspects lat. 3 & 1/2 fingers, there will be will be also sensory loss from med. 1/3 palm. also sensory loss from lat. 2/3 palm, if palmar cut. branch is involved. - If the cause is carpal tunnel syndrome, there will be paresthesia over lat. 3 1/2 fingers.  Radial & ulnar arteries Artery Radial Ulnar Beginning In cubital fossa, at level of radius neck as smaller of 2 terminal In cubital fossa, at level of radius neck as larger of 2 terminal branches of branches of brachial A. brachial A. Course 1-In forearm & at wrist: It runs downwards & laterally along lat. 1-In forearm & at wrist: Its runs obliquely downwards & med. reaching med. side & part of front forearm till wrist, where it turns backwards around of front forearm (upper 1/3), then it descends vertically along med. side forearm relations its lat. side. (lower 2/3) till wrist where it passes superficial to flexor retinaculum reaching hand. *Ant.: -In upper part: Brachioradialis. *Ant.: -In upper part: 5 superficial forearm muscles; Pronator teres, flexor carpi -In lower part: Skin, superficial & deep fascia. radialis, Palmaris longus, flexor digitorum superficialis & flexor carpi ulnaris. N.B.: Radial A. is quiet superficial throughout its course as -In lower part: Skin, superficial & deep fascia. compared to ulnar A. *Post.: It lies on muscles attached to radius forming radial A. bed; *Post.: Brachialis , flexor digitorum profundus & flexor retinaculum. Biceps, supinator, pronator teres, flexor digitorum superficialis, flexor pollicis longus & pronator quadratus. *Lat.: Superficial radial N. (in middle). *Lat.: Flexor digitorum superficialis. *Med.: Pronator teres & flexor carpi radialis. *Med.: Ulnar N. & flexor carpi ulnaris.. 2-In hand:. It crosses anatomical snuff box floor reaching hand 2-In hand: It lies lat. to ulnar N. & pisiform, being covered by palmaris brevis. dorsum where it passes between 2 heads of 1st dorsal interosseous muscle reaching palm, where it emerges between 2 heads of adductor pollicis & runs med. distal to metacarpal bases. End In palm as deep palmar arch. On flexor retinaculum by dividing into superficial & deep branches.  Radial & ulnar arteries A)Near elbow: *Ant. ulnar recurrent: Ascends to anastomose with ant. branch of inf. Branches ulnar collateral A. infront of med. epicondyle. *Post. ulnar recurrent: Ascends to anastomose with sup. & inf. ulnar collateral AA. on back of med. epicondyle. *Common interosseous: Short trunk passing backwards, reaching inter- osseous membrane upper margin, dividing into ant. & post. interosseous AA. 1-Ant. interosseous: -Descends infront of interosseous membrane (accompanied by ant. interosseous N.) between flexor pollicis longus & flexor digitorum profundus. -At upper border pronator quadratus, it pierces interosseous membrane reaching forearm back & descends deep to extensor retinaculum (in 4th compartment.) to end by joining post. carpal arch. Branches: Median A.: Supplies median N. Muscular: To forearm deep flexors & extensors. Nutrient: To radius & ulna. Anastomotic: Join ant. & post. carpal arches. 2-Post. interosseous: Passes backwards above interosseous membrane reaching forearm back, descending between superficial & deep forearm extensors (accompanied by post. interosseous N.). It ends by anastomosing with ant. interosseous A. Branches: Post. interosseous recurrent: Ascends to anastomose with middle collateral A. on back lat. epicondyle. Muscular: To forearm extensors.  Radial & ulnar arteries A)In forearm & at wrist: B)In forearm: *Muscular: To muscles on ulnar side forearm. *Radial recurrent: Ascends to anastomose with radial collateral A. infront of lat. epicondyle. *Muscular: To muscles on radial side forearm. *Ant. carpal: Passes med. infront of carpus to anastomose with C)At wrist: *Ant. carpal: Passes lat. infront of carpus to anastomose ant. carpal branch of ulnar A. forming ant. carpal arch. with ant. carpal branch of radial A. forming ant. carpal arch. *Superficial palmar: Descends through thenar muscles & ends by *Post. carpal: Turns backwards behind carpus to anastomose with post. anastomosing with ulnar A. completing superficial palmar arch. carpal branch of radial A. forming post. carpal arch. B)On dorsum hand: *Post. carpal: Passes med. on carpus back to anastomose with post. carpal branch of ulnar A. forming post. carpal arch. *1st dorsal digital: Supplies lat. side thumb. *1st dorsal metacarpal: Arises on hand dorsum before radial a. D)In hand: *Superficial branch: Curves lat. across palm forming passes between 2 heads of 1st dorsal interosseous, supplying superficial palmar arch. adjacent sides of thumb & index fingers. *Deep branch: Passes between abductor & flexor digiti minimi then penetrates oppenens digiti minimi (accompanied by deep branch of ulnar C)In palm : *Princeps pollicis: Arises from radial as it N.), anastomosing with deep palmar arch at base of 5th metacarpal. emerges between 2 heads of 1st dorsal interosseous supplying both sides of thumb palmar aspect. *Radialis indicis: Supplies lat. side of index palmar aspect. *Deep palmar arch.  Radial & ulnar arteries Arterial arches in hand Arch Ant. carpal arch Post. carpal arch Superficial palmararch Deep palmar arch Site Deep to flexor tendons. Deep to extensor tendons. Deep to palmar aponeurosis, but Deep to flexor tendons of palm. superficial to flexor tendons & median n. digital branches. Level Infront carpus On back carpus Mid shaft of metacarpals, 1/2 Just distal to bases of metacarpals, 1/2 inch distal to deep palmar arch. inch proximal to superficial palmar arch. Formation *Ant. carpal of radial A. *Post. carpal of radial A. *Ulnar A. (mainly). *Radial A. (mainly). *Ant. carpal of ulnar A. *Post. carpal of ulnar A. *Superficial palmar branch of *Deep palmar branch of ulnar A. *Anastomotic of ant. *Ant. interosseous A. radial A. (completed). (completed) interosseous A. *Post. interosseous A. *Recurrent of deep palmar arch. branches *2nd, 3rd & 4th dorsal *3 common palmar digital AA.: *3 palmar metacarpal AA.: Join 3 meta-carpal AA.: Each Run to clefts between med. 4 fingers, common palmar digital branches of divides into 2 dorsal digital each divides into 2 palmar digital superficial palmar arch. branches supplying palmar aspects of branches, supplying adjacent *3 perforating AA.: adjacent sides of med. 4 fingers. sides of med. 4 fingers. Pass dorsally through 2nd, 3rd & 4th intermetacarpal spaces to join dorsal *Palmar digital A.: To med. *Dorsal digital A.: To metacarpal AA. side little finger. med. side little finger. *Reccurent AA.: Ascend deep to flexor retinaculum to join ant. carpal arch. Surface Curved line across hand (convexity Curved line 4 cm across hand from anatomy directed distally) from distal proximal border of root of extended border of root of extended thumb. thumb (just distal to hamate hook). Relations Deep branch of ulnar N. lies in arch concavity.  Flexor retinaculum *Def. & site: Thick transverse band of deep fascia, infront of carpal bones, converting their ant. concave surface into a tunnel called carpal tunnel. *Attachments: -Med.: Pisiform & hook of hamate -Lat.: It splits into 2 laminae; -Superficial: Scaphoid (tubercle) & trapezium (crest) -Deep: Medial lip of trapezium groove. N.B.: In between the 2 laminae, there is a special tunnel, for flexor carpi radialis tendon & its sheath. -Above: Continuous with deep fascia of front forearm. -Below: Continuous with apex of palmar aponeurosis. *Structures passing superficial: From med. to lat. 1-Ulnar N. 2-Ulnar A. 3- Palmar cutaneous branch of ulnar N. 4-Tendon of Palmaris longus. 5 -Palmar cutaneous branch of median N. *Structures passing deep: A: In carpal tunnel; 1-One nerve: Median N. (most superficial structure). 2-Nine tendons: Tendon of flexor pollicis longus, 4 tendons of flexor digitorum superficialis & 4 tendons of flexor digitorum profundus. 3-Two synovial sheaths (bursae): Radial & ulnar bursae. 4-Recurrent branches of deep palmar arch: Deepest structure. B- In special tunnel: Flexor carpi radialis tendon & its sheath. *Muscles attached: -Lat.: Origin thenar muscles -Med.: Origin hypothenar muscles. - In middle: Insertion of palmaris longus tendon.  Carpal tunnel *Boundaries: -Sides & floor: Carpal arch, formed by ant. concave surface carpal bones. -Roof: Flexor retinaculum. *Contents: 1-One nerve: Median n. (most superficial structure). 2-Nine tendons: Tendon of flexor pollicis longus, 4 tendons of flexor digitorum superficialis & 4 tendons of flexor digitorum profundus. 3-Two sy