Thorax13BONYTHORAXANDJOINTS1st thoracic vertebraClavicle1stribRibs:1stSpine of2ndscapula3rdScapula4th5thInferior angle of scapula7th rib6thAngle of the 9th rib7th8th9th intercostal space9thFloating (free) ribs(11-12)10th12th11thSpinous process ofB. Posterior View1stlumbarvertebra1.10BONYTHORAX(CONTINUED) The superior thoracic aperture (thoracic inlet) is the doorway between theWhenclinicians refertothesuperiorthoracic apertureasthethoracic"outlet,"they are emphasizing the importantnerves and arteries thatthoracic cavity and the neck region; it is bounded by the 1st thoracic ver-tebra.the1stribsandtheircartilages,andthemanubriumofthesternum.passthroughthisapertureintothelowerneckandupperlimb.Hence,.Each ribarticulatesposteriorlywiththevertebral column.varioustypesofthoracicoutletsyndromesexistsuchasthecostoPosteriorly,all ribs angle inferiorly,anteriorly,the3rdto 1Othcostal carti-clavicular syndromepallor and coldness ofthe skin of theupperlagesangle superiorly.limbanddiminished radial pulse-resultingfrom compressionoftheThe scapula issuspendedfromtheclavicle and extends across the2nd tosubclavianarterybetweentheclavicleandthe1strib.7th ribs posteriorly
1st thoracic vertebra 1st rib Clavicle Scapula 7th rib Angle of the 9th rib 12th Spinous process of 1st lumbar vertebra Floating (free) ribs (11 - 12) 9th intercostal space Inferior angle of scapula Spine of scapula Ribs: 1st 2nd 3rd 4th 5th 6th 7th 8th 9th 10th 11th B. Posterior View Agur_Chap01.indd 13 11/14/2011 2:44:08 PM
14BONYTHORAXANDJOINTSCut edges of fibrous layerArticularof joint capsuleJugular(suprastermal)notchcavities ofClavicularClavicular notchsternoclavicularnotchSynovial-jointCostalmembrane1stcostalnotches:cartilage1stArticular disc-ManubriumManubriumAnteriorstemoclavicularClavicleInterclavicularligamentligamentManubriostemal jointCostal notchesSternal(stemal angle)2nd-2ndangleeABodyCostoclaviculal(stermebrae):ligament1st福1stcostal3rd-3rdcartilageBodyofsternumO2ndManubriumaB. Anterior View4th4thCostal3rdClavicularTransversenotchcartilages:ridge5th--4th5th6thXiphisternal7th6thXiphisternaljointjoint7thManubriumXiphoid processXiphoid processManubriosternal jointC. Lateral ViewA. Anterior ViewIntra-articularligamentSternocostalYear of synostosis:joints-In about 10% of adultsF (30-80 years)AnteriorsternocostalBodyofstemumradiateligamentsSternebrae1st121st year±2nd14thyear±InterchondraljointAnteriorcostaxiphoid ligament3rd7th year±Interchondral ligament4thCommonly aftermiddlelifeXiphoid processD. Anterior ViewE. Anterior View1.11STERNUMANDASSOCIATEDJOINTSA.Parts of sternum.B.Sternoclavicular joint.C.Features of the lateral aspect of the sternum.D.Ages ofossification of sternum.E.Stermocostal,manubriosternal,and interchondral joints.On the rightsideof thespecimen,thecortexofthestemumandtheexternal surfaceofthecostal cartilageshavebeenshavedaway
Jugular (suprasternal) notch Xiphoid process Xiphisternal joint Body of sternum 3rd 4th 5th 6th 7th 2nd Manubriosternal joint (sternal angle) Manubrium 1st costal cartilage Clavicular notch Transverse ridge A. Anterior View E. Anterior View Manubrium Sternal angle 1st 2nd 4th Xiphisternal joint 3rd Xiphoid process 7th 6th 5th 4th 3rd 2nd 1st Body (sternebrae): Costal notches: Anterior sternocostal radiate ligaments Interchondral ligament Anterior costoxiphoid ligament Interchondral joint Sternocostal joints Intra-articular ligament Manubriosternal joint C. Lateral View Clavicular notch Xiphoid process Manubrium Body of sternum Costal notches: Anterior sternoclavicular ligament Interclavicular ligament Articular cavities of sternoclavicular joint Cut edges of fibrous layer of joint capsule Clavicle Articular disc Synovial membrane Manubrium B. Anterior View Costoclavicular ligament 1st costal cartilage 21st year± 14th year± 7th year± In about 10% of adults (30-80 years) Commonly after middle life 1st 2nd 3rd 4th D. Anterior View Sternebrae Costal cartilages: 1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8 Year of synostosis: Clavicular notch Agur_Chap01.indd 14 11/14/2011 2:44:12 PM
Thorax15BONYTHORAXANDJOINTS1st ribSingle facetGroove foron headsubclavian veinGroove for2nd ribsubclavianarteryScalenetubercle1stribSuperiorfacet.Inferior facetCostal angleHeadTubercleHFNeckNeck6th ribB. Superior ViewCrest of neckShaft:Crest of headIntemal surfaceArticular partTubercleShaft:NonarticularpartExtemalsurface8th rib2nd ribCostalgrooveSite ofarticulation withcostal cartilageTubercle for serratus anteriorHeadSingle facet11thribNeckon headTubercleC. Superior ViewA. Posterior View12thrib1.12RIBSA."Typical"(6thand8th)and"atypical"(1stand 2nd and 11thand 12th)ribs.B.First rib.C.Second rib.Rib fractures.Theweakestpartof a rib is immediatelyanteriorto its angle.Themiddle ribs aremostcommonlyfractured
1st rib 2nd rib Costal angle 6th rib Shaft: Internal surface Shaft: External surface 8th rib Costal groove 11th rib 12th rib Site of articulation with costal cartilage Tubercle Nonarticular part Articular part Crest of neck Neck Head Crest of head Single facet on head Superior facet Inferior facet Single facet on head Head Head Neck Neck Scalene tubercle Groove for subclavian vein Groove for subclavian artery 1st rib 2nd rib Tubercle Tubercle for serratus anterior A. Posterior View B. Superior View C. Superior View Tubercle Agur_Chap01.indd 15 11/14/2011 2:44:16 PM
16BONYTHORAXANDJOINTSSpinousprocessForamentransversariumElements oftransverse process:TransverseCostalVertebral bodyCervical ribsA. Superior ViewManubriumBody3rd ribSternalforamenSupernumerarypart ofribandcostalcartilageXiphoid processD. Anterior View3rd ribB. Anterior View3rd costal cartilage1.13RIBANDSTERNUMANOMALIESA.Cervicalribs.Peopleusuallyhave12ribsoneachside,butthenumber1strib2nd ribmay be increasedbythepresence of cervicaland/or lumbar ribs (super-numeraryribs)ordecreasedbyafailureofthe12thpairtoform.Cervicalribs(present inupto1%of people)articulatewiththeC7vertebraandareFusionclinically significantbecausetheymay compress spinal nerves C8andT1ortheinferiortrunkofthebrachialplexus supplyingtheupperlimb.Tinglingand numbness may occur along the medial border of the forearm.Theymayalsocompressthe subclavian artery,resulting inischemicmusclepain(causedbypoorbloodsupply)intheupperlimb.Lumbarribsarelesscommonthan cervical ribs,buthave clinical significance inthattheymayconfusethe identityofvertebral levelsindiagnosticimages.B.Bifidrib.Thesuperiorcomponentofthis3rd rib is supernumeraryand articulatedwiththeC. Superior Viewlateralaspectofthe1ststernebra.Theinferiorcomponentarticulatedatthejunctionofthe1stand2ndsternebrae.C.Bicipitalrib.Inthisspecimen,therehasbeenpartialfusionofthefirsttwothoracicribs.D.Sternalforamen
Agur_Chap01.indd 16 11/14/2011 2:44:18 PM
ThoraxBONYTHORAXANDJOINTS11SuperiorarticularSuperior costal(demi-) facetTransverse costalfacetfor tubercle of 6th ribT6Joints ofTransverseprocesheadof ribRib6th ribrotatesTransverseprocess ofT7VertebralbodyCostotransverseT6jointInferior costalAxis of rotation(demi-) facet7th ribSpinousprocess of T7A. Lateral ViewRib glidesSuperiorarticularfaceTransverse costalfacet for tubercle110of 6th ribCrestof headVertebralbodyC. Lateral ViewSpinousprocessofT67thribTubercleof 7thribB.Posterolateral View1.14COSTOVERTEBRALARTICULATIONSA.andB.Articulatingstructures.Thesmootharticularpartofthetubercleof therib,thetransversecostalTherearetwoarticularfacetsonthehead of therib:alarger,inferiorcos-facetarticulateswiththetransverseprocessofthesamenumberedver-tal facet for articulation with the vertebral body of its own number,and atebra at the costotransverse jointsmaller,superiorcostalfacetforarticulationwiththevertebralbodyofthec.Movements atthecostotransversejoints.Atthe1stto7thcostotransversevertebra superior to the rib.joints,the ribsrotate, increasing the anteroposteriordiameterof the thorax;Thecrestofthehead ofthe ribseparatesthesuperiorand inferiorcostalat the 8th, 9th, and 10th, they glide, increasing the transverse diameter offacets.the upper abdomen
B. Posterolateral View Superior costal (demi-) facet Superior articular facet Transverse costal facet for tubercle of 6th rib Transverse costal facet for tubercle of 6th rib Transverse process of T7 Costotransverse joint Spinous process of T7 7th rib Inferior costal (demi-) facet Vertebral body T6 T7 T6 T7 Superior articular facet Spinous process of T6 7th rib Vertebral body Crest of head Joints of head of rib Tubercle of 7th rib Transverse process 6th rib Rib rotates A. Rib glides Lateral View C. Lateral View T6 T7 T9 T10 Axis of rotation Agur_Chap01.indd 17 11/14/2011 2:44:21 PM