Clavicle - Lecture Note

CLAVICLEDEFINATIONINTRODUCTIONIt is the ant bone of the shoulder girdle It is a non-typicallong bone as -is It has no medullary cavity(ii) It develops by membranous ossificationGENERAL FEATURES OF THE CLANCLEThe claricle has a shafe and 2 ends (red & lateral)MEDIAK END (STERNAL)(i) large, rounded or quadrangular in shape.(ii) Presents a small facet for articulation with the claricularfacetof manubrium stermi.DIPANKAR RAY(iii) Lower part of the fact extends slightly on the inferior surfaceof the medial end for articulation with the 1st castal carrilage(Fibrous Joint).(iv) Rough area above the articular facet gives attachment to theinterclasicular ligamentTHE LATERAL END (ACROMIAL)Flattend and carries an ovalfacet for articulation with the acromion process of scapulaat the acromio clavicular joint.Human Anatomy For ExamTHESHAFTOFCLAVICLEPresents letter. a double currature resembling theS.Med 2/3 is convex forwards while its lateral 1/3 is corvex backwards.LATERAL 1/3 OF THE SHAFTMEDIAL 2/3 OF SHAFTDIRECTIONIt is conver backwards to meetIt is convex forwards to widenthe coronial process of scapula.the space behind for the passagefrom not of neck to axilla.of the vessels & nerves passingSHAPEFlattend. having ant & posteriorbenders, uppercy lower surfaces.ant post, uppers lovershefaces.Cylindrical in form havingUPPER SURFSMOOTHSMOUTHANT- ASPECTAnterior burder is rough & maypresent a small tubercle (Delto idAnt surface is rough mediallyIts lower surface is rough andtubercle)(for origin of pecturalis major m)LOWERshows-Its lower surface is rough andshows-SURFACE(a) Conoid Tubercle.(a) A rough depressed impression.(b) Trapezoid line.b A grouve for insertion ofcubebrius.(c) A Nutrient foramen. CLAVICLE2PARTICULAR FEATURES OF THE CLAVICLEMUSCLES ATTACHEDMUSCLES ARISE FROM ANT ASPECT OF CLAVICLEPECTORALIS MAJORMUSCLE : from the medical 1/2 of the ant aspect.DELTOID MUSCLE From lateral 1/3 of the ant aspect.MUSCLES ATTACHED TO THE POSTERIOR ASPECT OF THE CLAVICLESTERNOMASTOID MUSCLE (ORIGIN): From the medial 1/3 of posterior& upper surfaces.TRAPEZIUS MUSCLE (INSERTION): Into the lateral 1/3 of post-aspectMUSCLE INSERTED INTO MIDDLE 1/3 OF THE INF SURFACESUBCLAVIUSLIGAMENTS ATTACHEDHuman Anarymy For FromCORACO-CLAVICULAR LIGAMENTIt is arey strong ligament connecting the lower surface of the1/3 of the claride to the upper surface of the coracoid processof Srapula.It has 2 parts:aConoid Part :- Attached to the Conoid Tubercle(b) Trapezoid Part : - Attached to the Trapezoid lineCOSTO -CLAVICULAR LIGAMENTIt connects the inf surface of the medial end of the clavicleto the 1st costo chonoral junction.INTER-CLAVICULAR LGAMENTIt above connects the Sterum the medial ends of the 2 elavicles, crossingIt is the only connection between the bones of the Rt & Itupper limbs.