Upper Extremity Muscle

8/8/2019 Upper Extremity Muscle

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Upper extremityUpper extremity



Surface anatomySurface anatomy

ClavicleClavicleManub riumManub riumJugu lar notch (s uprasternal notch)Jugu lar notch (s uprasternal notch)DeltoidsDeltoidsScap ula, Acromion, spine, coracoid process, fossa,Scap ula, Acromion, spine, coracoid process, fossa,bordersbordersHumer us, t ub ercle, bodyHumer us, t ub ercle, body

Ulna, head, olecranon process, ulnar nerveUlna, head, olecranon process, ulnar nerveRadius, radial nerve, styloid processRadius, radial nerve, styloid processCarpals, pisiform, scaphoid and trapezi um, anatomicalCarpals, pisiform, scaphoid and trapezi um, anatomicalsn uff boxsn uff box



B rachial Plex usB rachial Plex us



Brachial plex us formation .Brachial plex us formation .

The brachial plex us starts from the five ventralThe brachial plex us starts from the five ventralrami of therami of the spinal nervesspinal nerves , after they have given, after they have given

off their se gmental s upply to the m uscles of theoff their se gmental s upply to the m uscles of theneckneck . These are the five. These are the five rootsroots ..These roots mer ge to form threeThese roots mer ge to form three trunkstrunks : : "superior" or " upper" C5"superior" or " upper" C5--C6, "middle" C7, andC6, "middle" C7, and"inferior" or "lower" C8"inferior" or "lower" C8- -T1.T1.E ach tr unk then splits to form an anterior and aE ach tr unk then splits to form an anterior and aposteriorposterior divisiondivision ..



Brachial plex us formation .Brachial plex us formation .

The six divisions will re group to become theThe six divisions will re group to become thecordscords . The cords are named by their position in. The cords are named by their position in

respect to therespect to the axillary arteryaxillary artery ..TheThe posterior cordposterior cord is formed from the threeis formed from the threeposterior divisions of the tr unks.posterior divisions of the tr unks.TheThe lateral cordlateral cord is the anterior divisions from theis the anterior divisions from the

upp er and middle tr unks.upp er and middle tr unks.TheThe medial cordmedial cord is sim pl y a contin uatio n o f t heis si mpl y a co nti nuatio n o f t helo wer tru nk.lo we r tru nk.



Brachial plex us formationBrachial plex us formation

B ranches of the brachial plexusB ranches of the brachial plexus3 branches from the3 branches from the roots roots

Dorsal scap ular nerveDorsal scap ular nervearises fromarises from C5C5 root, s upplies theroot, s upplies the rhom boid m usclesrhom boid m uscles andand levatorlevatorscap ulaescap ulae ..

Nerve to s ub claviusNerve to s ub claviusarises fromarises from C5C5 andand C6C6 roots, s upplies theroots, s upplies the sub clavius m usclesub clavius m uscle

Long thoracic nerveLong thoracic nervearises fromarises from C5C5,, C6C6 andand C7C7 roots, s uppliesroots, s upplies serrat usserrat usanterioranterior




1 branch from the1 branch from the trunkstrunksSuprascap ular nerveSuprascap ular nerve

arises from the s uperior tr unk, s uppliesarises from the s uperior tr unk, s upplies supraspinat ussupraspinat us andandinfraspinat usinfraspinat us musclesmuscles

3 branches from the3 branches from the lateral cordlateral cordLateral pectoral nerveLateral pectoral nerve

suppliessupplies pectoralis majorpectoralis major andand pectoralis minorpectoralis minor ( by( bycomm unicatin g with thecomm unicatin g with the medial pectoral nervemedial pectoral nerve ) from C5, C6, C7.) from C5, C6, C7.

Musculocutaneo us nerveMusculocutaneo us nervefrom C5 and C6 it s uppliesfrom C5 and C6 it s upplies coraco brachialiscoraco brachialis ,, brachialisbrachialis andandbiceps brachiibiceps brachii . It then becomes the. It then becomes the lateral c utaneo us nerve of lateral c utaneo us nerve of the forearmthe forearm ..

Lateral root of theLateral root of the median nervemedian nerve

supplies C5, C6 and C7 fi bres to the median nerve.supplies C5, C6 and C7 fi bres to the median nerve.



Brachial plex us formationBrachial plex us formation5 branches from the5 branches from the posterior cordposterior cordUpper s ub scap ular nerveUpper s ub scap ular nerve

suppliessupplies sub scap ularissub scap ularis (upper part) from C5 and C6(upper part) from C5 and C6Thoracodorsal nerveThoracodorsal nerve

suppliessupplies latissim us dorsilatissim us dorsi with nerve fi bres from C6, C7 andwith nerve fi bres from C6, C7 and C8C8

Lower s ub scap ular nerveLower s ub scap ular nervesupplies the lower part of s ub scap ularis andsupplies the lower part of s ub scap ularis and teres majorteres major from C5 andfrom C5 andC6.C6.

Axillary nerve Axillary nervefrom C5 and C6, it s uppliesfrom C5 and C6, it s upplies deltoiddeltoid and a small area of overlyin g skin byand a small area of overlyin g skin byits anterior branch.its anterior branch.Its posterior branch s uppliesIts posterior branch s upplies teres minorteres minor and deltoid m uscles thenand deltoid m uscles thenbecomes thebecomes the upper lateral c utaneo us nerve of the armupper lateral c utaneo us nerve of the arm

Radial nerveRadial nervenerve fi bres from all 5 roots (C5nerve fi bres from all 5 roots (C5- -T1T1))largest nerve of the plex uslargest nerve of the plex ussuppliessupplies tricepstriceps brachii, the skin of the posterior arm as thebrachii, the skin of the posterior arm as the posteriorposteriorcutaneo us nerve of the armcutaneo us nerve of the arm ,, ancone usancone us, and the, and the extensor m usclesextensor m uscles of theof theforearmforearm ..




5 branches from the5 branches from the medial cordmedial cordmedial pectoral nervemedial pectoral nerve

from C8 and T1, it s uppliesfrom C8 and T1, it s upplies pectoralis majorpectoralis major andand pectoralis minorpectoralis minor

medial root of themedial root of the median nervemedian nervesupplies C8 and T1 fi bres to the median nerve.supplies C8 and T1 fi bres to the median nerve.medial c utaneo us nerve of the armmedial c utaneo us nerve of the arm

supplies the front and medial skin of thesupplies the front and medial skin of the armarm from C8 and T1from C8 and T1medial c utaneo us nerve of the forearmmedial c utaneo us nerve of the forearm

supplies medial skin of the forearm from C8 and T1supplies medial skin of the forearm from C8 and T1

ulnar nerveulnar nerveC7, C8 and T1 fi bresC7, C8 and T1 fi bressuppliessupplies flexor carpi ulnarisflexor carpi ulnaris , the medial 2 bellies of , the medial 2 bellies of flexor di gitorumflexor di gitorumprof und usprof und us, most of the small m uscles of the, most of the small m uscles of the handhand and the skin of and the skin of the medial side of the hand and medial one and a half fin gersthe medial side of the hand and medial one and a half fin gers



Anesthesia of the B rachial Plexus Anesthesia of the B rachial Plexus

The fact that the nerves of the brachial plex us areThe fact that the nerves of the brachial plex us aregrouped to gether acts as a benefit as well.grouped to gether acts as a benefit as well. LocalLocalanestheticsanesthetics such assuch as lidocainelidocaine oror bu pivacainebu pivacaine can becan be

injectedinjected in close proximity to thesein close proximity to these nervesnerves , renderin g an, renderin g anentire arm insensate and immo bile. The process of entire arm insensate and immo bile. The process of injectin g local anesthetic for this p urpose is calledinjectin g local anesthetic for this p urpose is calledregional nerve blockaderegional nerve blockade or more simply, a nerve block,or more simply, a nerve block,and it is a common proced ure inand it is a common proced ure in anesthesiaanesthesia . After an. After anonset time of approximately 10 to 15 min utes, theonset time of approximately 10 to 15 min utes, thetar geted arm will be f ully anesthetized and ready fortar geted arm will be f ully anesthetized and ready forsurgerysurgery . The patient can remain awake d uring the. The patient can remain awake d uring theens uing surgical proced ure, or he can be sedated withens uing surgical proced ure, or he can be sedated withmedications or f ully anesthetized withmedications or f ully anesthetized with general anesthesiageneral anesthesia



Peripheral nerve blockadePeripheral nerve blockadeThe use of peripheral nerve blockade (in this case, a " brachial plex us nerveThe use of peripheral nerve blockade (in this case, a " brachial plex us nerveblock") offers several advanta ges when compared to general anesthesia orblock") offers several advanta ges when compared to general anesthesia orlocal anesthesia :local anesthesia :

The patient can remain awake and breathin g on their own, th us protectin g The patient can remain awake and breathin g on their own, th us protectin g themselves from aspiration of stomach contents into the l ungs. By avoidin g themselves from aspiration of stomach contents into the l ungs. By avoidin g general anesthesia, patients with adverse reactions to general anestheticsgeneral anesthesia, patients with adverse reactions to general anesthetics((viz.viz. malignant hyperthermia, severe post malignant hyperthermia, severe post- -operative na usea and vomitin g,operative na usea and vomitin g,known hypersensitivity to a gents) can be s uccessf ully treated. Similarly,known hypersensitivity to a gents) can be s uccessf ully treated. Similarly,patients who experience n uisance side effects from general anesthesia s uchpatients who experience n uisance side effects from general anesthesia s uchas na usea, vomitin g, or excessive sleepiness can minimize these symptoms.as na usea, vomitin g, or excessive sleepiness can minimize these symptoms.There is no need to perform anThere is no need to perform an endotracheal int ub ationendotracheal int ub ation , the proced ure of , the proced ure of insertin g a breathin g t ub e into the trachea. Occasionally, s uch int ub ation isinsertin g a breathin g t ub e into the trachea. Occasionally, s uch int ub ation isunexpectedly diffic ult to perform, ca using injury to the patient.unexpectedly diffic ult to perform, ca using injury to the patient.The affected lim b'sThe affected lim b's sympathetic nervessympathetic nerves are anesthetized, leadin g toare anesthetized, leadin g tovasodilationvasodilation . This improves. This improves blood flowblood flow to the affected lim b and makesto the affected lim b and makesmicrovasc ular s urgical proced ures technically simpler.microvasc ular s urgical proced ures technically simpler.The lim b can remain n umb for several ho urs after s urgery, providin g The lim b can remain n umb for several ho urs after s urgery, providin g excellent pain relief.excellent pain relief.Deep and s uperficial str uct ures of the lim b are similarly anesthetized,Deep and s uperficial str uct ures of the lim b are similarly anesthetized,allowing extensiveallowing extensive surgical explorationsurgical exploration and correction to occ ur. This is inand correction to occ ur. This is incontrast to locally injected local anesthetics, which tend only to n umb contrast to locally injected local anesthetics, which tend only to n umb superficial str uct ures in the immediate vicinity of the injection.superficial str uct ures in the immediate vicinity of the injection.



B rachial plex us blockadeB rachial plex us blockadeB rachial plex us blockade is the preferred anesthetic techniq ue when :B rachial plex us blockade is the preferred anesthetic techniq ue when :

Surgery is expected to be limited either to a re gion between the midpoint of Surgery is expected to be limited either to a re gion between the midpoint of thethe humer ushumer us and theand the fingersfingers (in which case the brachial plex us block sho uld(in which case the brachial plex us block sho uldbe either abe either a suprasupra--clavicularclavicular,, infrainfra--clavicularclavicular, s ub coracoid, or axillary block),, s ub coracoid, or axillary block),OR surgery is expected to be limited to a re gion between the midpoint of OR surgery is expected to be limited to a re gion between the midpoint of the h umer us and the sho ulder (in which case the brachial plex us blockthe h umer us and the sho ulder (in which case the brachial plex us blocksho uld be an interscalene block). Beca use of the distri bu tion of the localsho uld be an interscalene block). Beca use of the distri bu tion of the localanesthetics on the vario us portions of the brachial plex us, s urgeriesanesthetics on the vario us portions of the brachial plex us, s urgeriescrossin g the midpoint of the h umer us often reveal patchy, unanesthetizedcrossin g the midpoint of the h umer us often reveal patchy, unanesthetizedportions of the arm. Such proced ures pro bably sho uld not be performedportions of the arm. Such proced ures pro bably sho uld not be performedunder re gional nerve block alone.under re gional nerve block alone.

AND ANDThere are no contraThere are no contra- -indications to a block s uch as infection at the intendedindications to a block s uch as infection at the intendedinjection site, si gnificant injection site, si gnificant antianti--coa gu lationcoa gu lation ,, allergyallergy oror hypersensitivityhypersensitivity to localto localanesthetic medications, or disproportionate risk in the event of a localanesthetic medications, or disproportionate risk in the event of a localanesthetic toxic reaction (anesthetic toxic reaction ( seiz ureseiz ure ) s uch as) s uch as gastric aspirationgastric aspiration in a patient in a patient who has not adeq uately fasted,who has not adeq uately fasted,

AND ANDThere will not be a need to perform aThere will not be a need to perform a ne urologic examinationne urologic examination immediatelyimmediatelyfollowing the s urgical proced ure,following the s urgical proced ure,

AND ANDPatient prefers this techniq ue over other availa ble and reasona blePatient prefers this techniq ue over other availa ble and reasona ble



I njuriesI njuries

Two inj uries types are reco gnised in brachial plex usTwo inj uries types are reco gnised in brachial plex usinjuries : Tra uma utic and O bstetric.injuries : Tra uma utic and O bstetric.Tra umatic inj uries often are the res ult of hi gh velocityTra umatic inj uries often are the res ult of hi gh velocityRTA's (Road Traffic Inj uries). The most common form of RTA's (Road Traffic Inj uries). The most common form of injury are the motorcycle drivers fallin g, with either theinjury are the motorcycle drivers fallin g, with either thehead/neck p ushed to the side ( upper plex us lesions) orhead/neck p ushed to the side ( upper plex us lesions) orwith their arm a bducted (stretched upwards) whichwith their arm a bducted (stretched upwards) whichprod uces a lower plex us inj ury.prod uces a lower plex us inj ury.The brachial plex us is s uscepti ble to inj uries that The brachial plex us is s uscepti ble to inj uries that prod uce a bduction of the thoracic lim b from the bodyprod uce a bduction of the thoracic lim b from the bodywall or a direct blow to the lateral s urface of thewall or a direct blow to the lateral s urface of the scap ulascap ula..



The cardinal si gns of brachialThe cardinal si gns of brachial

plex us av ulsion are :plex us av ulsion are :aa weaknessweakness in the armin the armdiminisheddiminished reflexesreflexescorrespondin g correspondin g sensory deficitssensory deficits

The nerve roots are stretched or torn from their ori gin by thisThe nerve roots are stretched or torn from their ori gin by thistra uma, since the menin geal coverin gs of the nerve roots aretra uma, since the menin geal coverin gs of the nerve roots arethinner than those in the peripheral nerve. Thethinner than those in the peripheral nerve. The epine uriumepine urium of theof theperipheral nerve is conti gu ous with theperipheral nerve is conti gu ous with the dural materdural mater , provi ding extra, providin g extrasupport to the peripheral nerves. In cases where the nerve rootssupport to the peripheral nerves. In cases where the nerve rootshave been torn, recovery is unlikely witho ut new experimentalhave been torn, recovery is unlikely witho ut new experimentalsurgical techniq ues.surgical techniq ues.The dia gnosis may be confirmed by anThe dia gnosis may be confirmed by an E MGE MG examination in 5examination in 5- -77days. The evidence of denervation will be evident. If there is nodays. The evidence of denervation will be evident. If there is nonerve cond uction 72 ho urs after the inj ury, thennerve cond uction 72 ho urs after the inj ury, then avulsionavulsion is most is most likely.likely.



Brachial Plex us and Nerves of Upper lim b

Supraclavicular nerveOrigin Muscle distribution

Dorsal scapular Ventral rami of C4, C5 Rhomboids & Lev. scapulae

Long thoracic Ventral rami of C4- C7 Serratus anterior

Nerve to subclavius Superior trunk, C4- C6 Subclavius, sternoclavicular joint

Suprascapular Superior trunk, C4-C6 Supraspinatus, infraspinatus,glenohumeral (shldr) joint



I nfraclavicular nerves

Origin Muscle distribution

Lateral pectoral Lateral cord, C5-C7 Pectoralis major, pectoralis minor

Musculocutaneous

Lateral cord, C5-C7 Coracobrachialis, biceps brachii, brachialis,

Median Lateral cord, C6-C7 Flexor carpi ulnaris, flexor digitorum profundus

Medial pectoral Medial cord, C8-T1 Pectoralis major/minor

Medial brachialcutaneous

Medial cord C8-T1 Skin on medial side of arm.

Medialantebrachialcutaneous

Medial cord, C8-T1 Skin over medial side of forearm



Infraclavicular nerve

Origin Muscle distribution

Ulnar Terminal of medial cord,C7, C8- T1

Half of flexor forearm muscles,small muscles of hand, skin onmedial of hand to ring finger

Upper subscapular Posterior cord, C5-C6 Superior subscapularis

Thoracodorsal Posterior cord, C6-C8 Latissimus dorsi

Lower subscapular Posterior cord, C5-C6 Inferior subscapularis and teresmajor

Axillary Terminal posterior cord,C5- C6

Teres minor, deltoids, shoulder joints, skin over inferior deltoids.

Radial Terminal posterior cord,C5- C6

Triceps brachii, anconeus, brachioradialis, extensor muscles of forearm, skin over

post. Aspect of arm andforearm.



Muscle Origin Insertion Nerve Action

Biceps brachii Coracoid process,supraglenoidtubercle

Radialtuberosity,

biciptalaponeurosis

MusculocutaneousC5 ± C6

Supinatesforearm, flexesforearm

Brachialis Anterior surfaceof distalhumerus

Coronoid process, ulnatuberosity


Flex andadducts arms

Cracobrachialis Coronoid process of scapula

Mid3rd medialsurface humerus


Flex andadducts arm

Triceps brachii LH: I nfraglenoidtubercleLat hd: posthumerus sup. Toradial grooveMedial Hd:

post. Humerus

inf. To radialgroove

Olecranon of ulna and fasciaof forearm

Radial nerve C6 ± C8

Extend forearm,long headsteadies head of humerus

Anconeus LateralepicondyleHumerus

Lat. Surfaceolecranon supof ulna

Radial nerve C7 ± T1

Assist triceps toextend forearm,stabilize elbow,adducts ulna in

pronation



B reakB reak



Axillary artery Axillary arteryBoundaries = lateral border first ri b to s uperior border of Teres minor m uscleBoundaries = lateral border first ri b to s uperior border of Teres minor m uscleDivision:Division:

1st division = from lateral border first ri b to medial border of pectoralis minor1st division = from lateral border first ri b to medial border of pectoralis minorBranchBranch = s upreme thoracic artery= s upreme thoracic artery

2nd division = from medial border of pectoralis m uscle to lateral border of same2nd division = from medial border of pectoralis m uscle to lateral border of samemusclemuscleBranchBranch ==Thoraco acromial arteryThoraco acromial arteryLateral thoracic arteryLateral thoracic artery3rd division = from lateral border of pectoralis minor to s uperior border of the Teres3rd division = from lateral border of pectoralis minor to s uperior border of the Teresminor m uscleminor m uscleBranch =Branch =Sub scap ular arterySub scap ular artery

Anterior circ umflex h umeral artery Anterior circ umflex h umeral arteryPosterior circ umflex h umeral arteryPosterior circ umflex h umeral artery



B rachial arteryB rachial arteryBoundariesBoundaries = distal ed ge of Teres major m uscle to C ub ital= distal ed ge of Teres major m uscle to C ub italfossa.fossa.B ranchesB ranches = 1. Deep brachial or Prof unda brachii artery = to= 1. Deep brachial or Prof unda brachii artery = to

posterior compartment of the armposterior compartment of the armRecurrent branch anastomose with the posterior circ umflex h umeralRecurrent branch anastomose with the posterior circ umflex h umeralarteryarteryLateral branch anastomose with the Radial rec urrent artery.Lateral branch anastomose with the Radial rec urrent artery.Posterior branch anastomose with Rec urrent interosseo us artery.Posterior branch anastomose with Rec urrent interosseo us artery.Collateral branchesCollateral branches

Superior ulnar artery anastomose with posterior rec urrent ulnar artery.Superior ulnar artery anastomose with posterior rec urrent ulnar artery.Inferior ulnar artery anastomose with anterior rec urrent ulnar artery.Inferior ulnar artery anastomose with anterior rec urrent ulnar artery.



Venous return Venous return

Deep veins = 2 to 3 joins to form the venaeDeep veins = 2 to 3 joins to form the venaecomitantes brachiales freely anastomose a bout thecomitantes brachiales freely anastomose a bout thebrachial artery.brachial artery.

superficial veinssuperficial veinsCephalic veins to the anterior of the lateral epicondyle to theCephalic veins to the anterior of the lateral epicondyle to thedeltopectoral trian gle, pierces the clavipectoral fascia to joindeltopectoral trian gle, pierces the clavipectoral fascia to jointhe axillary vein distal to first ri b..the axillary vein distal to first ri b..Basilic vein = medial epicondyle alon g the deep medialBasilic vein = medial epicondyle alon g the deep medialante brachial joins the brachial vein near the teres majorante brachial joins the brachial vein near the teres major

muscle to form the axillary veins.muscle to form the axillary veins.Median c ub ital veins = the connectin g veins betweenMedian c ub ital veins = the connectin g veins betweenthe cephalic and the basilica veins at the c ub italthe cephalic and the basilica veins at the c ub italFossa, it lies at the bicipital apone urosis..Fossa, it lies at the bicipital apone urosis..



Lymphatic drainageLymphatic drainage

Deep lymphatics accompany brachial veinsDeep lymphatics accompany brachial veinsinto the axillary lymph nodes.into the axillary lymph nodes.Superficial lymphatics alon g the s uperficialSuperficial lymphatics alon g the s uperficialveins into the :veins into the :

supratrochlear lymph nodes near the medialsupratrochlear lymph nodes near the medial

epicondyleepicondylesuperficial draina ge bypass most axillarysuperficial draina ge bypass most axillarynodes into the s ub clavian vein.nodes into the s ub clavian vein.



L igaments of the GlenohumeralL igaments of the Glenohumeral

Joint.Joint.There are several important li gaments in theThere are several important li gaments in thesho ulder. Li gaments are soft tiss ue str uct ures that sho ulder. Li gaments are soft tiss ue str uct ures that connect bones to bones. A joint caps ule is aconnect bones to bones. A joint caps ule is awaterti ght sac that s urrounds a joint. In thewaterti ght sac that s urrounds a joint. In thesho ulder, the joint caps ule is formed by a group of sho ulder, the joint caps ule is formed by a group of ligaments that connect the h umer us to the glenoid.ligaments that connect the h umer us to the glenoid.These li gaments are the main so urce of sta bility forThese li gaments are the main so urce of sta bility forthe sho ulder. They help hold the sho ulder in placethe sho ulder. They help hold the sho ulder in placeand keep it from dislocatin g. These are theand keep it from dislocatin g. These are theglenoh umeral li gaments (GHL)glenoh umeral li gaments (GHL)

Another li gament links the coracoid to the acromion Another li gament links the coracoid to the acromion-- coracoacromial li gament (CAL). This li gament cancoracoacromial li gament (CAL). This li gament canthicken and ca use Impin gement Syndromethicken and ca use Impin gement SyndromeLigaments attach the clavicle to the acromion in theLigaments attach the clavicle to the acromion in the

AC joint. AC joint.Two li gaments connect the clavicle to the scap ulaTwo li gaments connect the clavicle to the scap ulaby attachin g to theby attachin g to the coracoid process,coracoid process, a bony rid gea bony rid geon the scap ulaon the scap ula -- coracoclavic ular ligaments (CCL)coracoclavic ular ligaments (CCL)Ligaments of the Sho ulder Complex:Ligaments of the Sho ulder Complex:CCLCCL -- coracoclavic ular ligamentscoracoclavic ular ligamentsCALCAL -- coracoacromial li gamentscoracoacromial li gamentsSGHLSGHL -- Superior GlenoH umeral Li gament Superior GlenoH umeral Li gament MGHLMGHL -- Muperior GlenoH umeral Li gament Muperior GlenoH umeral Li gament IGHLIGHL -- Inferior GlenoH umeral Li gament Inferior GlenoH umeral Li gament



L igaments of the Rotator CuffL igaments of the Rotator Cuff

The tendons of the rotator c uff are the next layer inThe tendons of the rotator c uff are the next layer inthe sho ulder joint. Tendons are m uch likethe sho ulder joint. Tendons are m uch likeligaments, except that tendons attach m uscles toligaments, except that tendons attach m uscles tobone. M uscles move the bones by p ulling on thebone. M uscles move the bones by p ulling on thetendons. One important tendon that travels thro ug htendons. One important tendon that travels thro ug hthe sho ulder joint is thethe sho ulder joint is the biceps tendonbiceps tendon .. TheThebiceps tendon act ually begins at the top of thebiceps tendon act ually begins at the top of thesho ulder socket (the glenoid) and then passessho ulder socket (the glenoid) and then passesacross the front of the sho ulder to connect to theacross the front of the sho ulder to connect to thebiceps m uscle. (The biceps is the m uscle that biceps m uscle. (The biceps is the m uscle that weightlifters are always showin g off).weightlifters are always showin g off).TheThe rotator cuff rotator cuff t end o ns ar e a gro up of fo u r t end o ns ar e a gro up of fo u r t end o ns t hat co nnec t t he deepes t la yer of musclest end o ns t hat co nnec t t he deepes t la yer of musclesto t he hume r us.to t he hume r us. They ar e t he t end o ns of t heThey ar e t he t end o ns of t herotator cu ff muscles (le ft )rotator cu ff muscles (le ft )Tend o ns of t he sh o ulde r :Tend o ns of t he sh o ulde r :Fro m fro nt to back :Fro m fro nt to back :Su bsca pulari sSu bsca pulari sB ic eps Tend o nB ic eps Tend o nSup ra sp i nat usSup ra sp i nat usIn fra sp i nat usIn fra sp i nat usTe r es Mi nor Te r es Mi nor



Muscles of the sho ulderMuscles of the sho ulder

There are 30 m uscles providin g There are 30 m uscles providin g movement and s upport for themovement and s upport for thesho ulder complex. 15 m uscles movesho ulder complex. 15 m uscles moveand sta bilize the scap ula; 9 m usclesand sta bilize the scap ula; 9 m usclesprovide for glenoh umeral joint motion;provide for glenoh umeral joint motion;

and 6 s upport the scap ula on theand 6 s upport the scap ula on thethoraxthoraxThere are three important groups of There are three important groups of muscles aro und the sho ulder : muscles aro und the sho ulder : 1. Surface m uscles ( E xtrinsic) : 1. Surface m uscles ( E xtrinsic) : The lar geThe lar ge d eltoi d d eltoi d muscle forms themuscle forms theouter layer of m uscle. This is theouter layer of m uscle. This is thelargest, stron gest m uscle of thelargest, stron gest m uscle of thesho ulder. The deltoid m uscle takessho ulder. The deltoid m uscle takesover liftin g the arm once the arm isover liftin g the arm once the arm isaway from the side.away from the side.Pectoralis Major provides movement Pectoralis Major provides movement and s upport in the front of theand s upport in the front of thesho uldersho ulder



Deep ( Intrinsic) m usclesDeep ( Intrinsic) m uscles

. Deep m uscles (Intrinsic) : . Deep m uscles (Intrinsic) : The rotator c uff tendons attach to the deep rotator c uff m uscles.The rotator c uff tendons attach to the deep rotator c uff m uscles.These 4 m uscles are involved in raisin g the arm from the side andThese 4 m uscles are involved in raisin g the arm from the side androtatin g the sho ulder in the many directions. The rotator c uff rotatin g the sho ulder in the many directions. The rotator c uff mechanism also helps keep the sho ulder joint sta ble by holdin g themechanism also helps keep the sho ulder joint sta ble by holdin g thehumeral head in the glenoid socket. These m uscles are : humeral head in the glenoid socket. These m uscles are : sub scap ularis, s upraspinat us, infraspinat us and teres minor.sub scap ularis, s upraspinat us, infraspinat us and teres minor.3. Back Muscles (Posterior) : 3. Back Muscles (Posterior) : These m uscles are at the back of the sho ulder that sta bilise andThese m uscles are at the back of the sho ulder that sta bilise andmove the scap ula on the tr unk of the body. This group incl udes themove the scap ula on the tr unk of the body. This group incl udes the

trapezi us, rhom boids, levator scap ulae, and the serrat us anteriortrapezi us, rhom boids, levator scap ulae, and the serrat us anteriormuscles; and are concerned with sta bilisation and rotation of themuscles; and are concerned with sta bilisation and rotation of thescap ula.scap ula.



B ursas of the ShoulderB ursas of the ShoulderSandwiched between the rotator c uff Sandwiched between the rotator c uff muscles and the o uter layer of lar ge bu lkymuscles and the o uter layer of lar ge bu lkymuscles is a str uct ure known as amuscles is a str uct ure known as a bu rsa.bu rsa.Bursae are everywhere in the body. TheyBursae are everywhere in the body. Theyare fo und wherever two body parts moveare fo und wherever two body parts moveagainst one another and there is no joint toagainst one another and there is no joint tored uce the friction. A bu rsa is simply a sacred uce the friction. A bu rsa is simply a sacbetween two movin g surfaces that containsbetween two movin g surfaces that containsa small amo unt of l ub ricatin g fluid.a small amo unt of l ub ricatin g fluid.Think of a bu rsa like this : If yo u press yo urThink of a bu rsa like this : If yo u press yo urhands to gether and slide them a gainst onehands to gether and slide them a gainst oneanother, yo u prod uce some friction. In fact,another, yo u prod uce some friction. In fact,when yo ur hands are cold yo u may r ub when yo ur hands are cold yo u may r ub them to gether briskly to create heat fromthem to gether briskly to create heat fromthe friction. Now ima gine that yo u hold inthe friction. Now ima gine that yo u hold inyour hands a small plastic sack that containsyour hands a small plastic sack that containsa few drops of salad oil. This sack wo uld let a few drops of salad oil. This sack wo uld let your hands glide freely a gainst each otheryour hands glide freely a gainst each otherwitho ut a great deal of friction.witho ut a great deal of friction.



Muscles of the BackMuscles of the Back



Superficial m usclesSuperficial m uscles

MuscleMuscle Ori ginOrigin InsertionInsertion Action Action NerveNerveT rapeziusT rapezius Occiput,Occiput,

nuchal linenuchal lineClavicle,Clavicle,acromion,acromion,spine ofspine ofscapulascapula

Rotator,Rotator,adductor,adductor,lowers thelowers thescapula.scapula.

SpinalSpinalaccessoryaccessorynervenerve

LatissimusLatissimusdorsidorsi

T horacoT horaco- -LumbarLumbar

fascia,spinefascia,spines of lumbars of lumbar& sacral,& sacral,iliac crest,iliac crest,lower 4 ribslower 4 ribs

I ntertubercI ntertubercular grooveular groove

or bicipitalor bicipitalgroove.groove.

Extends,Extends,adducts,adducts,

medianmedianrotator ofrotator ofshouldershoulder

T horacoT horacodorsal ( longdorsal ( long

subscapularsubscapular))



Superficial, rhom boid layerSuperficial, rhom boid layerMuscleMuscle OriginOrigin InsertionInsertion Action Action NerveNerveLevatorLevatorscap ulascap ula

Post,Post,t ub ercle andt ub ercle andtransversetransverseprocessprocessC1C1--44

MedialMedialborderborderscap ula,scap ula,higherhigher

E levator andE levator androtator of rotator of scap ulascap ula

DorsalDorsalscap ularscap ularnervenerve

Rhom boidRhom boidminorminor

Nuchal li g.Nuchal li g.Spine C7Spine C7--T1T1

MedialMedialborderborderscap ula,scap ula,lowerlower

Add uct Add uct scap ulascap ulamedially,medially,depressor of depressor of scap ulascap ula


Rhom boidRhom boidmajormajor

Spine T2Spine T2 T5,T5,supraspinoussupraspinous

lig.lig.

MedialMedialborder lowerborder lower

Add uct Add uct scap ulascap ulamedially,medially,depressordepressor




Deep m uscles of the back,Deep m uscles of the back,

transversetransverse- - costal groupcostal groupSpleni us capitisSpleni us capitis from nuchal lig, spine of C7, T1from nuchal lig, spine of C7, T1 --3 to occiput ,3 to occiput ,mastoidmastoid

Spleni us cervicisSpleni us cervicis spines of T 3spines of T 3--6 to transverse process C 16 to transverse process C 1 --33

E rector spinaeE rector spinae med crest of scarum to lower 6 ribsmed crest of scarum to lower 6 ribs

Iliocostalis l umborumIliocostalis l umborum from spines T11 from spines T11 L5 , iliac crest to sacrumL5 , iliac crest to sacrum

Iliocostalis thoracisIliocostalis thoracis -- from lower 6 rib angle to rib 1from lower 6 rib angle to rib 1 --6/trnsvrs proc.6/trnsvrs proc.C7C7

Iliocostalis cervicisIliocostalis cervicis -- angle rib 3angle rib 3- -6 to trnsvrs poc. C46 to trnsvrs poc. C4- -66Longissim us thoracisLongissim us thoracis- - mid crest sacrummid crest sacrum

Longissim us cervicisLongissim us cervicis-- transvrs proc T1 transvrs proc T1 -- 55

Longissim us capitisLongissim us capitis-- transvrs proc. T1transvrs proc. T1 -- 5 , artic. Proc C 5 5 , artic. Proc C 5 -- 77

Spinalis thoracisSpinalis thoracis -- spines T11 spines T11 L2L2

Spinalis cervicisSpinalis cervicis -- C7 to spine C 2C7 to spine C 2



D eep layer, T ransverseD eep layer, T ransverse- -spinal groupspinal group

Semispinalis thoracisSemispinalis thoracis transvrs proc. T 6transvrs proc. T 6 --10 to spines C610 to spines C6- -T 4T 4

Semispinalis cervicisSemispinalis cervicis transvrs proc. T1transvrs proc. T1 --T 6, to spines C 2T 6, to spines C 2 --C 5C5

Semispinalis capitisSemispinalis capitis T ransvrs proc. C7T ransvrs proc. C7- -T 7, to nuchal plane of occiputT 7, to nuchal plane of occiput

Spinalis capitisSpinalis capitis -- transvrs proc. C7transvrs proc. C7- -T 7, to nuchal plane occiputT 7, to nuchal plane occiputMultifidusMultifidus

SacralSacral post sacr um to spines o C2post sacr um to spines o C2 L5L5LumbarLumbar mamillary proc.mamillary proc.ThoracicThoracic from transvrs processfrom transvrs process

CervicalCervical from artic ular proc C4from artic ular proc C4 C7C7RotatoresRotatoresLongiLongi transvrs proc of 1 verte bra to spine 2 verte bra a bovetransvrs proc of 1 verte bra to spine 2 verte bra a boveB revesB reves transvrs proc of 1 verte bra to next verte bra a bovetransvrs proc of 1 verte bra to next verte bra a boveInterspinalisInterspinalis connects apices of spines of adjoinin g verte braconnects apices of spines of adjoinin g verte braIntertransverseIntertransverse- - interconnects anterior t ub ercle of transvrs processinterconnects anterior t ub ercle of transvrs process



Sub occipital m uscleSub occipital m uscle

Rect us capitis posterior majorRect us capitis posterior majorFrom spino us process of axis, to inf n uchal line. E xtend andFrom spino us process of axis, to inf n uchal line. E xtend androtate the head to same siderotate the head to same sideTub ercle post arch of atlas, to inf n uchal line. E xtends head.Tub ercle post arch of atlas, to inf n uchal line. E xtends head.

Rect us capitis posterior minorRect us capitis posterior minorT ubercle on post arch atlas to inferior nuchal line.T ubercle on post arch atlas to inferior nuchal line.Extends head.Extends head.

Obliquu s capitis inferiorObliquu s capitis inferiorapex, and spine of atlas T rnsvrse proc. Atlas, turns head same sideapex, and spine of atlas T rnsvrse proc. Atlas, turns head same side

Obliquu s capitis s uperiorObliquu s capitis s uperiorT ransvrs proc. Atlas to occipital bone between nuchal lines.T ransvrs proc. Atlas to occipital bone between nuchal lines.Extends head and bends it to same side.Extends head and bends it to same side.



Actions, general . Actions, general .

Nerve s upply by all posterior primary divisions of spinal nerves.Nerve s upply by all posterior primary divisions of spinal nerves.Spleni usSpleni us draws head back, bends head laterally, rotates ace todraws head back, bends head laterally, rotates ace tosame side.same side.

IliocostalisIliocostalis-- bends verte bral col umn to side, l umborum depress ri bsbends verte bral col umn to side, l umborum depress ri bsLongissimus thoracis and cervicis bendsLongissimus thoracis and cervicis bends column to side, depress ribscolumn to side, depress ribs

LongissimusLongissimus capitis extends head, bends head to side, rotates face tocapitis extends head, bends head to side, rotates face tosame sidesame side

Semispinalis thoracis & cervicisSemispinalis thoracis & cervicis -- rotates column to same side.rotates column to same side.

Semispinalis capitisSemispinalis capitis extends head rotates head to opposite side.extends head rotates head to opposite side.Multifidus rotates column to opposite side.Multifidus rotates column to opposite side.Rotatores rotates column to opposite side.Rotatores rotates column to opposite side.I ntertransverse bends column to same side.I ntertransverse bends column to same side.



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Upper Extremity Muscle