FORELIMB de Ashdown Caballo

3 Th Folimh.ir

tg!3"1 s'lfrace feafures of the sapulr and brachialrcgirrs: lefr laEral yifl.

of the saouIay pa|pabIe.divergent hairut it does not

withers (spinous processof 4,5 and 6)

scaputa.dorsal border of cartilage

sp,r,e

cervical vertebrae,rrasyerse processes

humerus:cranial and caudal

divisionsof major tuberosit

deltoid tuberosi

position of divergent hairvorte

ulna, olecranon

humerus,laterarepicondle

radiUs, Iateral tu berosit

Fig.3.2 The bones of the forelimb.regions: left laterI view.

Sapular and brachial

The pa|pab|e bony prominenes shown in Fig.3 ] have been o|oured red. hepa|pabIe edge of the sapu|ar arti|age is shwn by a rd wire. Th tips of the spinousproesses at the withrs have not bn olourd.

Fig.3.3 Surface fetures of the brahial, ntebralridilarpal regions : left Iatera!view.The palpable bony prominens hav ben shaved h sufae fa:u"s :, :-.. _a-:.and th Ioation of the arpa| pad (hestnut) on the mdia| side of the irl i- ] ] j.aantebrahium, are shown in Figs 7.1,7.3,7 5and7 7. he |ateraI promie .--+dista| extrmity of the radius is often a||d the Iatera| sty|oid proess. bli : s :a .mtaphysea|.

humerus, cranial and

, .';--'u..ir

-----.-.---deltoidtuberositposition of divergent hairvorteutna, orccranon

humer us, later al epicond le

r ad i u s, l ate r al tu be ros it

radius,lateralprominence of distaleXtremit

position of radiocar palioint

accessor carpal bone

proimal etremit ofmetacarpal bone lV

Fig.3.4 Bones of the fore!imb. Brahia!, antebrahial andarpa! regions: left lateralview.h pa|pab|e bony prominens shown in Fig 3 3 have been o|ourd rd hartiular prooess situatd just dista| to th marked metaphysa| prominne of thradius is the so-a||ed .IatraI styloid prosS of th radius': it is, in fact, the distaIepiphysis of the uIna and it artiu|ates with the ulnar arpa| bone.

g5 aiaeous lt's|es of A'e sellr nd brachiellqfrr: left latera| YU. serfiii fsi' in whih the utaneous musles lie, has been opened both

ly to sttow the under|ying mus|es. These mus|es are more fu||y

Fig.3.6 Superfiia! strutures of the sapular and brahia!regions: left lateralview (1).The supefiia| fasia and the Utaneous musc|es have been removed. During theprevious dissetion of the neck (see Chapter 2) the omotransversrius ndbrahiocepha|icus muscles (shown intat in Figs.2.3 and 2.4) were transected(Frg.2.7).

m. trapezius:pars cevicalis pars thoracica

Nical crest

scapula, spine

superficial fascia(cutedge)

humerus, majortuberosit

humerus, deltoidtuberosit

brachial fascia

supeiicial fascia(cutedge)

nn. spinales rr. cutaneidorsles laterales:

CVIIIl

m. serratusventralisceNlcls

m. subclaviusm. supraspinatus

lnn. cervicalessupeiiciales

m. omotransversariusm. unohoideus

a carotis communisv. juguIaris eterna

n. supraclavicularis (CV I )m. cleidocephalicus

,}.,merus, major tuberosin- cutaneus brachii

latera]is (n. aillaris)m. cleidobrachialis

m. triceps brachii (caputlaterale)

rn - rctoralis descendens

superficial fascia(cutedge)

m, trapezius:parsthoracicapars cervicalis

m. cutaneus trunci

m. cutaneusomobrachialis

m, triceps brachii

olecranon

scapula, spinenn. thoracici rr. cutaneidors/es lateralesm' /tlssimus dorslm. infraspinatusaponeurosis ofm. deltoideusm. tensor fasciaeantebrachiim. deltoideusm. serratus ventralisthoracism. triceps (caput longum)n. intercostobrachialisdeep tascia coveringm. obliquus eternusabdominism' cutaneu trunciv. thoracica supeiicialisolecranon

m. cutaneu s omobr ac h i a I i sin superficialfasciav. cephalia

Fig.3.7 Superficia! structures of the salr br*9regions: left laterl view (2).he ervial trapezius mus|e has been removed and the |atissimus dorsi aseto show the scapu|ar attahments of the eviaI and thorai parts of tl.re verrmserrate mus|e. The fuII extent of this musIe is see when the scapula is rerove(Fig.3.10).

m. rhomboideus ceryicis

m. splenius

m. serratus ventraliscervlcts

m. subclaviusm. deltoideus

m ilioostalisce/tcts

m. omohoidusv. jugularis eterna

m. sternothroideushUmerus, major tuberosi

m. cleidocephalicusm. sternocephalicus

m. triceps brachii:caput longumcaput laterale

m' petoralisdesendes

n. cutaneus antebrachiilateralis (n radialis)

+.^^^-;', ^^.^l l l |I oPaLIUJ ' Pol thoraia

scapulacranial anglecartilagecaudal anglem serratusventralisthoracts

cva[JuIa'lI l ^,,^-^^^;^^},,^t r t JUtr)r dSIJtr toIUom infraspinatus

m omotransversariusm latissimus dorsi (cut)deep fascia coveringm obliquus eternusabdominism. cutaneus truncim. tensor fasciaeantebrachiiv. thoracic a superf ici al i sm pectoralisscedesm.cutaneu s omo brach i al is

Fig.3.8 Axi!!arystructuresbefore removalof the leftforelimb:dorsalview.h trnzil rerhomboideus andVentraI serrate musIeshave been ut' and thescapula has beenabduted and viewedfrom abov to displaythe emergene of thbrahia| pIexusbtwen the two partsof th sa|enus musIe-Fig.3.9 shows a futherstage in this dissetionof the axilla

m serratus ventralisthoracis (cut edge)

n meoranus

n thoracicus laiera

n thoracodorsahs

n radiaJis

nn- p,tarajs Jr

n .ltlLis

m sca/enus:dorsalisventralis

emergence of pleusbrachialis

n musculocutaneus

n. suprascapularis

a v suprascapularis

n subscapularis

leftforelimb tt

F33 Axilhrsilrfirres beforerernoval of the leftforelimb: caudl view.--e forelimb has now been furtherouted to display the axiIIa moreomp|etely. The nerves and bIoodressels of the axilla have been.orther dissetd to revea| their:opographial reIationshi ps.Futher detaiIs of trunk and limb aresnown in Figs 3 10 and 3.15.

m. serratus ventralis cervicis

n. suprascapuas

n subscapularis

n. thoracodorsalis

m. subclavius

m- serratus ventralis,ervj etthoracis

a.v. sUprascapulas

m. subscapularis

m /atrsslmus dorsi

m. teres major

a.v subscapularis

m. cutaneus trunci

m scalenus ventralis

m serratus ventralisthoracis

n. medianus etn. musculocutaneus

n aillaris

a. aiIIaris

v ailIaris

n. radialis

nn. pectorales caudales

lnn. axillares

n thoracicuslateralis

rib cage

m. pectoralis ascedes

v thoraica superficialis

a v. thoracodorsalis

03.10 The pectora!d ventral serratesles after removaIof; lorelimb: left lateralx.bralis, rhomboideus, trapeziuslventral serrate muscles haven inised to remove theinb. The nerves of the brahiaIls are not arranged to show thesition before removaI of the his is, however, shown in3.48.

m. r hom boi d an s tlracis

m rhomboideus cervic,sm sptentus

m longissimusthoracism. serratus ventralis:

cer'tclsthoracis

m. iliocostaliscervlcis

m scalenus ventralisn. phrenicus (CVI)

a carotis communisI nn. cervicales profundi

caudalesm sternothrohoideus

v. jugularis externalnn. ceNicales

super-ficiales

a. cerv ical is s u perf ici al isr. deltoideus

m. subclavius

v cephalica

m. pectoralisdescedens

cutedgeofm trapezius(parsthoracia)

dorsoscapular ligament,deep, middle andsuperficial parts

rn serrtus dors/cranialis

m. iliocostal is thorlsmm. intercosta|es eternin thoraicus longusm s/enus dors/lsplexus brachialisn. thoraodorsalisn, thoracicus lateral issuperfiiaI tendinouspart of m' serrtusventralis thoracis

nn. pectorales caudalesrn' serrtus ventralisth or ac i s i nte r d i g it ati n gwith m. obliquusexternus abdomi nis (cut)

a'v' aillarisa. thoracica eternam rectus thoracis

m. pectoralis asedens m' pectoral i s trasyersus

fi

Fr$.t 1 Superfici! strufurs of the ]eft antebrahium andcnps: rosilral Yiew._-l il-l t ben removed from the trunk. he skin and suoefiiaI fascia have beeniE,-l. to sw the supefiiaI vessels and nerves, but the antebrahiaI musIes aref_ .sted by the strong antebrahial fasia. The specimen at this stage of ss:lo'l is a|so shown in Fios.3.1 2-3..1 4.

radius:mediaI stloid processl ate r al st l oi d p roce ss

Fig.3.12 Superricial strutures of the leftcarpus: Iaterlview.he spimn is at the sam stage of dissetion as that shown in Figs.3.1 1 , 3

,1 3 and314

- retora]isdescedes

.n petoralis ascedes

m biceps brachii

m pctoral i s lrasyersus

v. cephalica

m fleor carpi radialis

radius

m etensor carpi radialis

n. cutaneus antebrachi icrani alis ( n. aill aris)

m. omotransversarilJs

m. cleidobrachialis

m. brachialis

v cephalica

n. cutaneus antebrachiilateralis (n radialis)

m tensor carpi radialisradius, l ateral tube rosit

m. etensor digitorumcommunts

m. abductor digiti Ilongus

m. etensor carpi radialis

m tensor digitorumcommunls

rete arpi dorsale


m. cleidobrachialis

n cutaneus antebrachiilateralis ( n. radi alis)

n. cutaneUs antebrahiicanialis (n aillaris)

n cutaneus antebrachiimedialis(n. musculo cutaneus)

m extensor carpi radialis

m. extensor digitorumcommUn

v. cephalica cessorla

v cephalicaaessorlr carpeus dors/is

metacarpaltuberosit

antebrahium nd

m. triceps brachii:caput longumcaput laterale

m. cutaneus trunci

v. thoracica superf ici alis

m. pectoralis ascedes

olecranon

m' fleor digitorumprofundus (caput ul nare)

n. cutaneus antebrachiicaudalis (n. ulnaris)

m' etensor carpi ulnaris

m. etensor dioitorumlatra|is

a. lnterosse cranialis


n. ulnaris, r. dorsalis

.9.t,. ll, -.....arpus: cuoal vlew.he speimen is at the sme stage of dissetion as that shovin " Fs.

. . 3 1; -] .iFor a omment on the use of th term.lateraI s|oid proess. see not g =g i

m. cutaneustruncl

v thoracica superf icialis

m tensorfasiaeantebrachii

a.v collateralis ulnaris

m. fleor arpi ulnaris:caPut ulnare

caput humerale

m. etensor digitorumcommunls

m etensor carpi ulnaris

m' fleor carpi ulnaris

n. ulnaris r. dorsalis

lateral coll ateral carPalligament

radial carpal bone

Fig.3.14 Superficial strutures of the left antebrahium andarpus: medialview.The speimen is at the same stage of dissetion as that shown in Figs.3.1 1 -3..1 3.

n. pectoralis caudaiis

m pectoralis asede'rs

v mediana cubiti

m pectoralis trnsyersusn. cutaneUs antebrahiicaudalis (n. ulnaris)

d ee p antebrachi al fascia

n. cutaneus antebrahiimedialis(n. musculocutaneus)

v cephalica

radius:lateral sty loid processmedial stloid process

a v radialis

medi al collateral carpalligament


ulnar carpal bone

m pectoralisascedensa.v collateralis ulnaris

m, pectoalisdesedes

v. cephalicam. biceps brachii

v. mediana cubiti

n. ulnarislaceftus flbrosusm. etenso carpi radialis

n. cutanes atebrachi imedialis(n' musculocutaa,s1v' ce phal ia essiradius

radius, mdial stboprocessextesor reon.,tn-m. abdlJt i iIonglrs

rnetarp J'r"Js

m. cutaneus trunct

v. thoracica su Peiicialism. tensor fasciae

antebrahiim pectoralis transversus

n. cutaneus antebrachiicaudalis (n. ulnaris)

deep antebrachial fasciav. cephalica

m. flexor carpi radialism. fleor carpi ulnaris

n. cutaneus antebrachiimedialis

(n musculocutaneus)

a.v. radialis


fleor retinacuIum

proimal etremit ofmetacarpal bone ll

Frg.ts heEfrtrrarrrdtacfii|regions: medialvifl._.

-s|es that join:-r -c to the trunk-.r en Ut. seeig 10. buttheir:tahments to thespu| and humerushve ben oreserved.No attemDt hs benmade to display theai||ary vessels andneves in their orrettopgraphiaIpositions. hese arshown in Figs 3 43-3.51

m. rhomboideus thorlsscapular cartilage

m. serratus ventralisthoracis

n. subscapularis

m. subscapularis

n. thoracodorsalis

m.latissimus dorsi

m. teres major

a.v. thoracodorsalis

n. radialis

n. ulnaris

n thoracicus lateralislnn. axillares

m. cutaneus truncinn. pectorales caudales

v. thoracica supe r-f i ci al is

a.v. collateralis ulnaris

m. rhomboideus ervilsm serratus ventralisceryl/sa. scapularis dors/isn suprascapularism. supraspnatusm. subclaviusn aillarisa. suprascapularisn meotanusn musculocutaneusa.v. subscapularisa.v. aillaris

nn. petorales cranialesa.v. thoracica eternam pectoralisdescedensm' pectoralis asendesv. cephalicav. mediana cubitim. pectoralis trsyersus

_10

n. ulnaris

|ig.Q.t6 The nerues of the brchil plexus of ttreleft forelimb: medial view.This is a Ioser view of a part of the specimen shown in Fig.3.15.

n. thoracodorsalis n. suprascapularis

nn. pectorales caudales a.v. thoracica externa

Fi9.3.17 The left median artery, vean and nerve atthe medial cubitl region: medil v.ew.

pu|se may be taken and the median nerve is surgia||y aessibIe.

m. tensor fasciae antebrachii n pectoraliscaudalis

n. subscapularis

a. suprascapularis

n. radialis

n, ulnaris

n. medianus

n. musculocutaneus

a.v axillaris

a.v- subscapularis

a.v. thoracodorsalis

nn. pectorales crani ales

n. thoracicus lateralis

lnn. aillares

m' pectoralis asendensv. thoracica eternaa. collateralis ulnarisn' cutaneus antebrahiicaudalis (n. ulnaris)m. biceps brachiim. pectoral is desedensm. fleor carpi radialiscut edge of deepantebrachial fasciav. cephalicav. mediana cubitiv. medianalacenus fibosus

m. brachialisa. medianar. muscularis tomm. fleoresn. mdianusm. N cto r al i s tr aselg.6radiusm. fleorcari rclifsm. extensor IFi |#

m flexor carpi ulnaris v. cephalica acesso

I.'

Frg.|E S|rrr.lures of the le'ft brhil region'rE0rhcrn rrd Garpus: rostral view.

he Iong tendon in the bieps musle (|aertus fibrosus) is lea seeninserting with the extensor rpi radiaIis. his speimen is aIso shown inFigs.3.19-3.24.

m. infraspinatus

m. deltoideus

m. triceps brachii (caputlongum)

humerus, majortUberosit



n. cutaneus antebrachiiI ateral i s ( n. r ad i al i s)

m' etensor carpi radialis

n. cutaneus antebrachiimedialis(n. musculocutaneus)

lacrtus flbrosus

m' etensor digitorumcommunrs

v transversa cubiti

m- etensor digitorumommunls

rete carpi dorsale

radius, distal end:lateral stloi d processmedial stloid process

etensor retin acul u m otcarpus

a. suprascapularis

m. supraspinatus

a' aillaris

humerus, minortuberosit

m. Nctoralis ascendes


m coracobrachialis

m. biceps brachii

m brachiocephalicus

m brachialis

v. mediana cubiti

a.v mediana

medial collateral cubitalIigament

m. fleor caroi radialis

radius


m abdutor digiti llongus

v ceohalicaccessorl

B.19 Structures of the sapular and brahial3ions nd the antebrachium: |eft laterl view.

The strong omobrahiaI, brahiaI and antebrahia| fsiae have beenremoved. This speimen is aIso shown in Figs.3.18 and.2U3.24.

scapula, cranial angle

m' serrtus ventraliscervicis (cut edge)

scapula, tuberosit ofsptne

m. supraspinatus

m. infraspinatus, tendonpasstng over malor

tUberosit

numerus, greatertuberosit

m. teres minor

humerus, deltoidtuberosi

m. biceps brachii

a. circumflea humericranialis

m biceps brachii,lacertus fibrosus

m cleidobrachialis

m. brachialis

m extensor carpi radialis

m etnsor digitorumcommunls

m' etensor digitorumIateralis


. interossea cranialis

carpus

metacarpus

!'':'.:..t'.

i;.,'.:': ' jt:.l'..1

-li: ' .'.: z'

scapula, caftilage

scapula, caudal angle

m. serratus ventralisthoracis (cut edge)


m. tensor fasciaeantebrachii

m. deltoideus

n cutaneus antebrachlcranialis (n ailIaris)

m. triceps brachii (caputIaterale)

n, cutaneus antebrachiilate ral is (n. radi alis )

olecranon

humerus,lateralepicondle

radius' lateral tuberosit

m etensor carpi ulnaris(m ulnaris lateralis)

m. fleor digitorumprofundus (caput ulnare)

m. fleor digitorumprofundus (caputhumerale)

n. ulnaris, r. dorsalis

accessory alpal furc

I

F330 SEutrres of the ntebrachium rrdGillls: lefr Iteral vi*._.

s figur'e reveIs the dista| part of the speimen shown in Fio.3.19.

rn. ticeps brahii1 altal,e,.Js ate brachii

raialis (n. aillaris)

a. circmflea humericranialis

Iacertus flbrosus

m cleidobrachialis

m. etensor digitorumlateralis


m. etensor digitorumcommus


a /lerosse cranialis

radi us, distal etremit

rete carpi dorsale

carpus

metacarpus


m triceps brachii (caputlaterale)

olecranon

radius, l ateral tUberosit

. m.'fleor digitorumprotu nous, caput ulnare

a v. collateralis ulnaris

rn etensor carpi ulnaris

radius,! ateraJ stloi d process

rete carpi dorsale

n' ulnaris r dorslis

asso| carpal bone

m. triceps brachii:caput longumaput Iaterale

n. cutaneus antebrachi ilateralis (n radialis)

olecranon

a. collateralis radialis

m' fleor digitorumprofundus (caput ulnare)

humerus,lateralepicondIe

radius, lateral tuberosit

m. etensor carpi ulnaris(m ulnaris lateralis)

v collateralis ulnaris

m. fleor dioitorumprofundus (caputhumerale)

n. ulnaris, r dorsalis

accessor arpal bone

Fig.3.21 .Structures of the left brachil region,antebrahium nd arpus: cudal view.]h_.spe9en is at the stage of disstion shown in Figs.3.19, 2o, .22,.23 and.24'

n medianus etn musculocutaneus

v. brachialis

m tnsor fasciaeantebrachii

v.transversa cubiti

n.meotanus

n cutaneus antebrachiicaudalis (n. ulnaris)m. fleor carpi ulnaris:caput ulnarecaput humeralen ulnasm. fleor dioitorumsupeiiciat

m. flexor digitorumprofundus (caputhumerale)

m fleor carpi ulnais

radius, medial sloidprocess

n cutaneus antebrachiimedialis(n. musculocutaneus)

a.v. radialis

Structures of the left scapular nd brachialantebrahium and arPus: medi! view.

speimen is t the stage of dissetion shown in Figs.3..| 8-3.2.1 nd

scapular cartilage

scapula, caudal angle

m. subscapularis

m. teres malor

m. triceps brachii (caputIongum)

a. thoracodorsalis

n. radialis

v. brachialis

n. ulnaris

a. brachialis


m tnsorfasciaeantebrachii

a. ul naris collateralis

n utaneus antebrachiicaudalis

m flor carpi radialis

m, fleor carpi ulnaris

a.v. radralis

n. cutaneus antebrachiimedialis

(n. musculocutaneus)

fleor retinaculum

lrss IFigs anteto the trunk.

m. sr,atJs yer*iscag/Io''!F

m. suprasqirfr.

n. subscagtlaris

n. suprascapttaris

n. aillais

a. suprascapulais

a aillaris

m. pector al i s asendens

m. coraobrahialis

m. biceps brachii

lnn. cubitales

m. cleidobrachialis

v. mediana cubiti

a.v mediana

n. medianus

m. extensor carpi radialis

laceftus fibrosus

av' transversaubiti

radius

etensor retinaculum

v. cephalica accessor

m. abductor digiti I longus

n. subscapularis

n. suprascapularisn aillaris, ramitom teres majorm. supraspinatus

n. axillaris

a suprasapularisa aillarisa. subsapularis


m. pe cto r al i s asendes

m coraobrachialis

n. musculoUtanaJs,r. muscularis distalis

m. cleidobrachialis

m. biceps brachfr

v. medianatim. braliaIs

/er[ fibr.s

m.erte'rid*srfra.farrjd.offr

The left brahial region and ntebrahium:vtew.

is a Ioser view of a oart of the soecimen shown in Fio 3.22.

m. subscapularis

m. teres malor

m tensorfasciaeantebrachii

a. thoracodorsalis

n radialis

n. ulnaris

a.v. brachialis

lnn. cubitales


n. cutaneus antebrachi icaudalis

a.v. medianaet n. medianus

medi al coll ateral cubitalligament (including' m. pronatorteres)

m. fleor carpi radialis

m. fleor carpi ulnaris:caput ulnare

caput humerale

Eg.i.| he Eir ilEbrdlium arrd GaIPus: med.alU.l.i .bser vi d a prt of the speimen shown in Fig.3.22.

m- tensor fasciaeantebrachii

n' ctaeus ntebrachiicaudalis (n. ulnaris)


deep antebrachial fascia

a v. mediana

m. fleor carpi ulnaris(caput ulnare)

m' fleor carpi radialis

Inn. cubitales

n. medianus

m, bieps brachii

v. mediana cubili

m. brachialis

n. medianus

ramus muscularis tomm' fleores

m. biceps brachii,lacertus fibrosus


a.v. transversa cubiti

etensor retinaculUm(cut edge)

radius, medial stloidprocess

n. cutaneus antebrachiimedialis(n. musculocutaneus)

v ephalica acessofla

m. abductor digiti Itongus

m. fleor carpi ulnaris(caput humerale)

a. radialis

v cephalica

accessor arpal bone

v. radiatis

fleor retinaculum

ig..25 Deeper structures of the left scapular andrhial regions: rostrl view.E supraspinatus musIe has been removed from the supraspinouss to show the suprasapu|ar nerve and the origin of the bieps brahiiusl. he deItoid mus|e has aIso bn removed. The intermediate

m' rhomboideus cerylis

scapular cartilage

senalus ventraliscervtcts

scapula:cranial border

sptnesupraspous fossa

n. suprascapularis

m subscapularis

scapula:coraoid process

supraglenoidtubercle

a. suprascapularism. coraobrachialis

m. supraspinatus(inseftions on minor and

major tuberosities)

a. aillaris

m. biceps, tendon inintertuberal groove

humerus, minortuberosi

m. coracobrachialis

m. biceps brachii

m. cleidobrachialis

m. brachialis

laceftus fibrosus

tuberosity of the humrus is not visibIe in the intetubr} groilE lt scovered by the bips tndon whih is mou|ded upon th oot, ]ribetween major and minor tuberosities. his speimn is ai53 3r'3- 1Figs..26 and 3.28

m. infraspinatus

scapula, neck

m infraspinatus


humerus, majortuberosit

n utaneus antebrachiicranialis (n. aillaris)


n. cutaneus antbrachiilate ral i s ( n. r ad i al is )

m. extensor carpi radialis

n' cutaneus antebrahiimedialis(n. musculocutaeus)

m. etensor digitorumcommunls

9J5 .Deeperslruturs of the tft sepular ad bhiel!rts: laEla| Yiew.sle shows the full extent of the infraspinatus mus|e ande.

scapula:suprspous foss

catilagesptne

caudal anglecranial bordercaudal border

m. subscapularisa. suprascapularisn. suprascapularis

scaputa:neck

supraglenoid tuberclem. supraspinatus (cut)

humerus, majortuberot

a. circumf|ea humericaudalis

a. circumflexa humericranialis

m. brachialis

lacertus fibrosus

m. cleidobrachialis

F19.3.27 The humeralgroove' brahialismuscle and rd.a| nerve:left lterl view.he Iatera| head of the trieosmusle has been reseted to revea|th brahia|is mus|e in its humera|groove, and the assoiated nerveand artery. In older textbooks thisfeature of the shaft of the humerusis aI|ed the musulospira| groove.

m. serratus ventralisthorais

origin of m deltoideus

m. infraspinatusm. triceps brachii (caputIongum)

m. teres minorn. aillarism. deltoideus (cut)humerus, deltoidtuberositm, bieps brachiim' triceps brachii (aputlaterale)n. cutaneus antebrachiilateralis (n radialis)m. etensor carpi radialisoIeranon

humerus,lateralepicondlem. etensor digitorumcommunts

m. biceps brachii(tendon in

inteftuberal groove)a. ircumtlexa humeri

caudalis

m. infraspinatus

m. teres minorm. triceps brachii (caput

Iaterale)m. deltoideus


m. brachialis in humeralsu/cus

a. circumflea humericranialis

humerus,lateralepicondle

humerus, majortuberositn. cutaneus antebrachiicranialis (n. aillaris)a. profunda brachiin. cutaneus antebrachiilateralis (n radialis)n. radialism. trieps brachii (caputmediale)m. triceps brachii (caputlaterale)m. fleor diaitorumprofundus (caput ulnare)

m. etensorcarpi radialis

m. etensorcarpi ulnaris

n. aiIlaris


g..28 The left brhial artery ulnar and median nerves:edilview.e s of dissetionow Th veins haveen hial region to showl arteries and nervs more |ear|y Thepraspinatus muscIe has ben removed toow the origins of the bieps brahii andraobrahialis musles from the sapuIa. Theor musIe of the antebrahiaI fasia hasen removed

I

m rhomboideus torlset ervlls

scapular cartilage

m rcres malor

n aillaris (reflectedventraIl)

a. sUbscapu/r,s

m tensorfasciaeantebrachii

a. thoracodorsalis

n. radialis


n. ulnaris

m triceps brachii (caputlongum)

a brachialis profundaa. brachialis

m. triceps brachii (caPutmediale)

n. ulnaris

n cutaneus antebrachiicaudalis (n. ulnaris)

olecranon

humerus, medialepicondle

a ulnaris collateralism fleor carpi ulnaris

(caPut ulnare)

m. fleor carpi ulnaris


m. serratus ventralis:pars thoracispars ceNtcts

m. subscapularis

. subsapu/aris

n. suprascapularis

a. suprascapu|as

scapula, supraglenoidtubercle and coracoidprocess

m. coracobrachialis,tendon

humerus, minortuberosit

m. biceps brachii

m. supraspinatus

a. aillaris

m. coracobrachialis

m' pector aI i s asedens

n. musculocutaneusr' muscularis proimalis

m. biceps brachii

n. musculocutaneusr. muscularis distalis

lnn. cubitales

m. cleidobrachialis

v medianaubiti

a.v. mediana

n medianus

m. brachialis

laceftus fibrosus

F'g.al Deep Usselsarrd rges of the leftatebhium: lteralvil.a,[: of tre ommon digita| extensor-;sle has been rmoved to show:e rania| iterosseous atery andranhes of the radia| nev.

m cleidobrachialis

m. brachialis

m. biceps brachii(lacerlus fibrosus)

n cutaneus antebrachiimedialis

(n musculocutaneus)

m eIensorcarplradialis

m etensor digitorumommUnls

a v transversa cubiti

a v interossea cranialisat rlerosseous spe

radius

a.v. interossea crani ali s

m abductor digiti Itongus

m. etensor Carpiradialis

a.v. interossea cranialis

m etensor digitorumcommunts

m triceps brachii(caput laterale)

olecranon

a. col lateralis radi ali s

m fleor digitorumprofu ndus (caput ulnare)

lateral col lateral cubitalligamenthumerus,lateralepicondIe

m. etensor digitorUmlateralis

n radialis

ulna

m. extensor carpi ulnaris(ulnaris lateralis)

m' fleor digitorumprofundus (caputhumerale)

m. etensor digitorUmlateralis

93.30 Deep vesselsid nerves of the leftEbrachium: medilr(1).flexor arpi radia|is and f|exor u|naris musIes have been removd (see a|so Fig .22)*w the median nerve with itsu|ar branhes and thernon interosseous atrv

n. cutaneus antebrachiicaudalis (n ulnaris)

m triceps brahii (caputtongum)

olecranon

m. triceps brachii(caput mediale)

m fleor arpi ulnaris(caPut ulnare)

a.v. col lateral is ulnaris

m fleor digitorumprofundus (caput ulnare)

m' fleor carpi ulnaris(caput humerale)


medial rad ial tuberosit

n. medianusrr musculares

to mm. fleores

m fleor digitorumsuperficialis

n medianus

v mediana


m. fleor carpi ulnaris

n. ulnaris

a brachialis

n medianus

a. collateralis u ln aris

lnn. cubitales

v brachialisv. mediana cubiti

humerus, medialepicondle

n cutaneus antebrachiimedialis(n musculocutaneus)

laertus fibrosus

m brahialismedi al collateral cu bitalligament (includesm. pronator teres)a profundaantebrahiia.v. transversa cubiti

m etensor carpiradialis

Iaceftus fibrosus

n. palmaris medialis

n. palmaris lateralisradius

F!9-3| reP.csztdtofIftsftaEbratrium:

'fid YieU (2).

' fleor rpi u|naris mus|e hasen rrved to disp|ay thestrLtures lying deep to its tendonof iertion (see a|so Fig.3'32). prt hs been removed from thesuperfiia| digita| f|eor mus|e tostw the radia| and humeraI headsof the deep flexor muscle.

m. triceps brachii (caputIongum)

n. cutaneus antebrachi icaudalis (n. ulnaris)m' fleor dioitorum

p rof u n d us ( c a pufu t n a re )n. utnas

m. fleor digitorumsuperficialis

a. profunda antebrachi im' fleor digitorumprofundus (caput

humerale)m' fleor digitorumprofundus (caput

radiale)m. flexor digitorum

superficialisn. palmaris lateralis

1n. medianus)

n ulnaris r. dorsa/n. ulnaris r. palmaris

v. cephalica

n. palmaris lateralis(n. medianus et n ulnaris)

m. fleor carpi ulnaris(cutedge oftendon)

accessory carpal bonea.v. radialis

m. triceps brachii (caputmediale)

a collateralis ulnarislnn. cubitales

m. biceps brachii

v medianacubitin cutaneus antebrachiimedialis(n. musuIoutaneUs)lacertus flbrosusm. fleor carpi radialism' fleor carpi ulnarisn. medianus (r. muscularis)a.v. transversa cubitiv. meolanan meotanusn. palmaris medialisn. palmaris lateralism. fIeor carpi radialism. etensor carpi radialisradiusa. medianav. mediana r palmarisradiUs' medial stloidprocess

medial collateral li gament

m. abdutor digiti l longus

.32 Vessels andrves of the left arpus:diIview.iis a c|oser view of a oart of thtion shown in Fig 3.31 ' heper strutures ar shown In;.3.4] and '42, The more dista|ons of the Iimb are shown in;.3.36 and 3.40.

m fleor digitorumprofu ndus (caput ul nare )

m. fleor digitorumprofundus (caput

humerale)

m. fleor digitorumprofundus (caput

radiale)

m, fleor digitorumsuperficialis

n. ulnas


n. palmaris lateralis

n ulnaris r. dorsalis

n ulnaris r palmaris

a mediana r palmaris

m, etensor carpi uInaris

cut edge of m. fleorcarpi ulnaris

n. palmaris lateralis(n. medianus et n. ulnaris)

acessor carpal bone

cut edge of fleorretinaculum

v. radialis r palmarissupedicialis

n medianus


n palmaris lateralis

n palmaris medialis

v. mediana

raolus

n palmaris medialis

a. meonna

a. radialis


v. cephalica

v. mediana r. palmaris

v. radialis

radial carpal bone


metacarpal bone llproimal etremil

t

F{tgSElrrcs ofl E-erpl.lsrd prcximal

r3s.3.34-3.36 show]se regions at theae stage of: ssetin. The:croximate extents. 1-e sovia| tendons:.eaths are indiated dotted bIue |ines.

Fi9.3.34Strutures ofthe Ieft carpusndmetaarpus:lateralview.Th soimn is thatshown in Figs 3 33,3.35 and 3 36. Thacessory Iigament o1the deep digita| f|xormus| is aIso knownas the hek Iigamentor aroa| head of thismus|e.

m.etelrIpt rdialis

medial collateral carpalligament

m abductor digiti Ilongus

metacarpal tuberosit

a radialis r. carpeusdorsa/ls

metacaroal bone lll

m etensor carpi radialisa. /terossea cranialis

r ad i Us' lateral stloidproess


intermedi ate carpal bone

rete carpi dorsalecarpal bone lV

metacarpal bone lll ,tUberosit

tendon from m. etesordigitorum communis

(caput radiale)to m. etensor

digitorum lateralis


m, etensor digitorumlateralis


m fleor digitorumprofundus, ligamentum

acessoflUrna metacarpeadorsal,s

iltmetacarpal bone lllmtacarpal bone lV

distal extremity

m. lnterosseus(suspesory ligament)

radius:medial sIoid processI at ral st l oi d p roce ss

. tterossea cranialis

snov i al ten do sheaths

cut edge of extensorretinaculum

lateral col late ral arpalligament

rete carpi dorsale


rete carpi dorsale

tendon of m etensordigitorum lateralis



m etensor carpi ulnaris,insertions

ulnar carpal bone


lateral collateralligamentof carpus

metacarpal bone lV,proimal etremit

deep metacarpalfascia(cut)

m fleor digitorumprofundus

a. metacarpeapalmaris lll

m fleor digitorumsuperficialis

n palmaris medialisr communtcans

v digitalispalmaris communis lll

m. fleor digitorumprofundus

m. fleor digitorumsuperticialis


n. ulnaris r palmaris

m. extensor digitorumlateralis

m. fleor carpi ulnaris(insertion)

m' etensor carpi ulnaris(insertions)

I ate r al col I ate r al car p alligament

acessory arpal bone

fIeor retinaculum ofcarpus

deep metacarpal fascia(cut)


a metacarpeadorsalilt

m. fleor digitorumsuperficialis

n ulnarisn. meonnus

a.v mediana r palmaris

v cephalica

accessory arpal bon

n. palmaris lateralis(n medianus et

n ulnaris)

a.v. radialis

a v. digitalis palmariscommunis ll

n. palmaris medialisr. communtcans


rn. terosseus

m. fleor digiIorumsuperficialis

n. palmaris lateralis(n medianus)a mediana, r. palmaisradius, medial sloidprocess

v. cephalica


n palmaris lateralis(n medianus et n.ulnaris)


a.v. radialis

n palmaris medialis(n. medianus)

n. palmaris medialisr communtcans

a metaarpea dorsalis ll

m. fleor digitorumsupeiicialis

m. /terosseus(suspesory ligament)

m' fleor carpi radialis


metacarpaltubrosit


metacarpal bone ll,proimal etremit

metacarpal tUberosit

a. radialis r. carpeusdors/

metacarpal bone lll

a. metacarpea dorsalis ll

metacarpal bone ll ,distal etremit


Fig"35Strgfi.lrcs dthe leftcilpllsndmetaa]pus:plmr Yiew.The spetrnen is tna:shown in Figs.3 333.34 and 3.36. nef|exor aroi uInarismus|e has beenremoved to eooseth origin of the |atera'oalmar nerve

Fi9.3.36Strutures ofthe left arPusand proximalmetaarpus:medialview.The speimen is thatshown inFigs.3.30-3.35. Theateries in thisdissetion are shownmore clearly inFig 3.40.

t

Ftg3.S..Itrsdesadztrbsdthelfi cpus armetacarts:dorsal Yi._rs

speimen is aIsosl.!rm in igs.3. 38-3-4o. The dissetions.ows the three majora.(eries ontributin g to:'e dorsal arterialletwork on the aroushe disoosition of thesynovial tendonsheaths of the arouss shown in Fig.3.33

Fi9.3.38Musles ndarteries of theleft carpus andmetarpus:laterlview.he veins, nrves andsuoerfiiaI tissushave been removd todispIay th mus|es ofthe region. Theartris hav beenpreservd to oovidrefrne points forthe positions of othersuperf iiaI strutursthat hav beenrmoved (omparewith Fig 3.34).

m. e,?so.Ip| rialis

radius

radius' medial sloidproess

m. abductor digiti Itongus

metacarpal tuberosity

a. radialis r. carpeusdors/

metacarpal bone lll

phalan l

m etensor digitorumommUnls

lterosse cranialis

rad i Us, lateral st loidproess

rete carpi dorsale

I ate r a I col I ate r al I i g ament

metacarpal tuberosit

tendon from m, etensordigitorum communis tom etensor digitorum

lateralis

m. extensor digitorumlateralis

a metacarpea dorsalis lll

metacarpal bone lV,distal etremil

metacarpal bone lll

proimal sesamoid bone

metacarpal bone lll,distal etremit

rn ,terosseus, tendon tom. etensor digitorUm

communls

a- Uansversa cubiti

/lerosse cranialis

radi us, late r al st loidproess

rete carpi dorsale

lateral collateral carpalgament

tendons fromrn /terosseusto m. extensor digitorumcommunts

m' etensor digitorumlateralis

n. ulnaris r dorsalis(displaced)

m. etensor carpi Ulnaris


accessoriometacarpalligament

metacarpal bone lV ,proimal etremit

m' fl.eor digitorumprotundus

m' fleor digitorumprofundus, ligamentumaccessonum

m' fle.or.digitorumsupe|cIaIls

a digitalis palmariscommunis ll

m. terosseus

palmar ligamentoffetlock joint

proimal phalan

m etensor arpi Ulnarisn Ulnas

m etensor digitorumIateralis

n ulnaris r palmarism etensor arpi ulnaris

radius, latral stloidproess

n palmaris lateralisaccessory arpal bonelateral col lateral carpal

ligament

acessorio_me ta ar p alligament

metacarpal bone lVm. extensor digitorum

lateralis

a. metacarpea dorsalis lll

rn. ,lerosseus

a digitalis lateralis


m. etensor carpi ulnaris

v. mediana r palmaris

acessory carpal bone

cut edge of fleorretinaculum

a.v. radialisa. mediana

m' fleor digitorumprofundus,ligamentum

accessortum

a. digitalis palmariscommunis ll

m, fleor digitorumsuPerficialis

m fleor digitorumprofundus

metacarpal bone ll,distal etremit

palmar ligament ofretloR joint

proimal sesamoid bone

medial tendon fromm. interosseus to m

etensor digitorumcommunts

m. flexor arpi radialis

m. fleor digitorumsupeiicialisn. medianusa. radialis

v. cephalicaradius' medial sloidproessa.v medianar. palmarism. fleor carpi ulnaris,inseftion (cut)

medial collateral carpalligament

fleor retinacuIum cut toepose arpal canalmetacarpal bone ll


metacarpal bone lll

m fleor digitorumsuperticialis

a digitalis medialis

palmar ligamentoffetlock joint

v cephalicaradius, medial stloidproessm. abductor digiti Ilongus

medial collateral I igamentof carpus

m. etensor arpi radialisinsefting on metacarpaltuberositmetacarpal bon llproimaletremit

a. radialisr. carpeus dors/ls


metacarpal bone lll

m. rnferosseus

m. etensor digitorUmcommunls

medial collateralmetacarpophalangealligament

F339tustes andarterbs dfteleft arprsandmetGarpus:palmar Yiew.The f|exor retinacu|Uwhih forms theoalmar wall of thearpa| ana|, hasbeen Ut to exoose thCaroal anaI. FurtherdetaiIs of the ana|and its ontents areshown in Figs.3.4.land3.42.

Fi9.3.40Muscles andarteries of theleft carpus andmetaarpus:media! view.his dissetion is aIsoshcwn in Figs.3.37-3.39.

il

Frga"4l he left arpl Ganl and jts corrtents:ofi$ u

g..42 he left carpalanaland its contents:Hique caudomedial view (2).

he tendon of the superfiia| digita| f|exor musle has ben E.dled o;:the arpa| ana| to dispIay its aessory' or hek, Iigrnet r frrthe auda| surfae of the radius' he aessory |igarrflt ot t]e dedigital flexor tendon is shown in Figs.3.34 and 3.38.

lacertus fibrosus inm etensor arpi radialis

raotus

n. medianus

v. mediana



v. radialis


n palmaris medialis(n. medianus)

m. fleor digitorumsu pe rf ici al is, I i gamentu maccessoum

cutedge of carpalsnovial sheath

a radialis

medial carpal collateralligament


a. digitalis palmariscommunis ll

metacarpal bone ll ,proimaleXtremit

a. radialis r carpeusdors/is


metacarpal bone lll

metacarpal bone ll

m. fleor digitorumprofundus (caput ulnare)

m. fleor digitorumprofundus (aput

humerale)

m. etensor carpi ulnaris

m fleor digitorumsuperticialis

a. meolana

a radialis proimalis

n ulnaris


n. palmaris lateralis(n. medianus)

snovial carpal sheath offleor tendons, s novia|

cavtry

n. ulnaris r. palmaris


n palmaris lateralis(n. medianus et

n. ulnaris)

cutedge of inseftion ofm' fleor carpi UInaris


a. radialis

m. fleor digitorumprofundus

m fleor digitorumsupeiicialis

olg]Deda|

Egl3.{3 Stsrrcrcsatilttic inlet of a

fiod: ht side inYTEU.

he lfi thorai wa|I ad theltrcb visera have beenrerD\.ed. he audaI ervia| andrlil thorai regions of the rightside are displayed. Thesubsequent disstions of thisspeimen (Figs.3.44-3.51 ) showthe right forelimb, dissted from itsmediaI aspet whi|e sti|| attahed tothe trunk.

a- vertebralis(sinistra)

pleus brachi a/ls slnlster(C7 'C8'1 '2)

rn. sa/eUs:dorsa/lsventralis

m.logus colli

oesopnagus

t. vagosmpathicus(sinister)

trachea

a. carotis communis(detra et sinistra)

a'v' vertebraIis (detra)

m. omohoideus

t. vagosmpathicus(dexter)

m. scalenusventralis

v jugularis eterna(detra)

m. sternocephalicus

m. sternoth rohoi deu s

v. cephalica

manubrium of sternum

t' smpathicus

a.v' scapularis dorsl(sinistra)

a'v. cervialis profunda(sinistra)

a, cervicalis profunda(detra)

t. costoceryla/,s(deter)

pleus brachialis(deter)

ribs 1 ,2lnn. mediastinalescraniales

a. subclavia deitra

a. cerv i cali s su perficial is

pleural covering ofintercostal spaces 1 ,2

a.v. aillaris

a' thoracica eterna

a.v. thoracica interna

ribs 1,2(left costal cartilageattachments, cut)

m - longissimus thoracis

Inn. sternales craniales Inn. sternales craniales

Fig.3.44 Right brchil plexus arrd erir* vss d tb ;foal: medialview (1).he strutures |ying media| to the insertion of the vetral s|eus n.te h'e tremoved to show hw the mus|e separates the brahia| p|exus frorn tr'e axilrvesse|s t the crania| border of the first rib.

costal cartilage of rib 1

Fig.3.45 Right brachial plexus and axillary vessels of thefoal: medialview (2).he strnum and the right first rib have now been removed, revealing the origins of thesubc|avius mus|e andthe nerves arising from the brahiaI p|exus.

trachea

a. carotis communis

t' vagosmpathicus

v. jugularis eterna

v. cephalica

m. sternothrohoideus

a.v. cervicalissuperficialis

sternum, manubrium

oesophagus

tacnea

a. carotis communis(detra)

t. vagosmpathicus(deter)

a.v. aillaris

v. cephalica

m. pectoralisdescedens

m. subclavius (origins)

m. pectoral is transversus

m. scalenus ventralis a.v. vettebralis(dete) @etra)

a. thoraciinternarr. i nte rstales ventales

a cervicalis profunda

l. ostoeryical,

rib 1 with part of itsendothoracicfasciaremoved

m. sa/enus ventralis

m. intercostalis internusin fi rst inte rcastal spe

a.v. aillaris

a. thoracica eterna

a. thoracica interna

pleus brachialis

position from which rib 1has been removed

m' i nte rcosta l i s etenusin first intercostal sc

a. thoracica eterna

ribs 2'

m. i nte r tafr sr?'te.6in sedinterostflspae

m. trsyersljs t'ais

rigmti2.(dlte,l,)

m. longus colli

HgrS-16*uilres of ]igftt xil|h thefoal:medhl yiew (1).--e flrst frve ribs and] veatral serrate-s|e have been.er.rved to revea| the.,ght i|la. hesub|avius mus|e hasatso been cut awav.

oesopgus

trachea

a.v vertebralis

a carous communis

t. vagosmpathicus

m. subclavius

n pectoralis cranialis

a v. aillaris

v cephalica

n. pectoral is cranialis

m. pectoralisdesedes

m. pectoralis trasyersus

n. pectoralis cranialis

m subclavius

a.v. aiIlaris

n Actora]is asendes

rjtn. Ntorales caudales

^ toralis asedes

remnants of riahtthoracic wall -

t. costoeryic,s

a cervicalis profunda

n. thoracodorsalis

pleus brachialis

a. thoracica eterna



v. thoracica superficialis

m pectoralisasedesFig.3.47

- Strutures of the right axitl in the foal:medialview (2).he superfiial petora| muscles have been removed.

n. thoracodorsalis

n. medianus

n. radialis

m. cutaneus trunci


v. thoracica supedicialismedial deep antebrachial

fascia

pIeus brachialis

Fig.3.48 Structures of the right axilla in the fol:medialview (3).Further dissection reveals the vessels and nerves of the region re fully nd stwsthe xiIlary |ymph nodes.

Fig.3.49 Strutures of the right ax.lla in the foal:medialview (4).The axillary vein has been shortened to reveal the axillary loop formed bymusuloctaneous and median nerves. The remova| of the thoraodorsal and |ateralthorai vesse|s and nerves revea|s more c|ear|y the musIes of the ail|a.

trachea

a.v. vertebralis

t. vagasympathicusn. pectoralis cranialis

m. subclavius

n. musculocutaeus

n. ulnarisa' aillaris

n. medianusv. aillaris

v ' thoracica eterna


m' pectoralis asendens

a.v veftebralism. scalenusventralis

tacnean pectoralis cranialisa. carotis communis

t. vagosmpathicusm. subclavius

n musculocutaneusa. axillaris

ansa aillarisn. pectoralis cranialis

n. rnedianus

m. longusdit. ostocer,.,6

a. cervicalis protwt,

m. subscapularism.teres major

n. thoracodorsalis

n' aillarisa.v. subscapularis


a.v. thoracodorsalisn. radialis

n. i nte rco sto b r ac h i al i s

lnn' aillares

v. thoracica superficiales


m. longus collim. subscapularisn. aillarism. teres malor

a.v. subscapularis

a. thoracodorsalis

m.latissimus dorsin. radialis

v ' aillarisn. ulnarisv. thoracia externa

m' pector al i s asendes

,

+59 !frrs dthe m ax.lla er brecftial rcglorr oflilH:fidYU.ilqE''fi'o pe,or| rr.sle hs bee removed.

Fig.3.51 The right xillary artery in the foal: medialview.The nerves of the brahial p|exus have been removed from around the xil|ary artery toshow its branhes and the brahia| artery'

tracheaoesopagus

m. scalenus ventralisa. carotis communis

m subclaviusa v. veftebralis

m. pectoral I s ascedensn. musculocutaneus

ansa ailIarisnn. petorales caudales

m. coracobrachialisn. musculocutaneus

r muscularis proimalism. biceps brachii

n. medianusn. musculocutaneusr. muscularis distalis

v. cephalicav. mediana cubiti


oesopr,agust. vagosmpathicus

tracheaa. carotis communis:

detra et sinistrat. vagosmpathicus

m. scalenusventralism. subclavius

m. pectoralis asedesa suprascapularis

a. aillarisa. circumflexa

humeri cranialisn. musculocutaneus

r- llscularis proximalis

m- aracobrachialis

m. biceps brachii

n. mtculoaltaneusr. us'J,aris dista]is

m.longus collit. ostoceryicalis

a. cervicalis profunda

m. subscapularis

n. aillaris

m.latissimus dorsi

m. teres major

a.v. subscapularis

n radialisn. ulnaris

a.v. brachialis

m. pectoralis ascendesInn cubitales



n. Utaneus antebrachiicaudalis (n. ulnaris)

m.Iongus collia v. vertebralist' costoervicalisa. cevialis profundapleus brachialism. subscapularisn. axillarisa. circumflea humericaudalis

a. thoracodorsalism. teres major

a.v. subscapularisa.v. brachialis

n. medianus

n. ulnaris

lnn cubitales


FORELIMB de Ashdown Caballo

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