Y khoa, y dược - The muscular system: Part C

10 The Muscular System: Part CMuscles Crossing the Shoulder JointNine muscles cross the shoulder joint to insert on and move the humerusMuscles Crossing the Shoulder JointSome originate off the scapula; others originate off the axial skeleton Three are prime movers of the armPectoralis major Latissimus dorsi Deltoid Actions include flexion, extension, adduction, abduction, and rotation of humerusMuscles Crossing the Shoulder JointPLAYA&P Flix™: DeltoidPLAYA&P Flix™: Latissimus dorsiPLAYA&P Flix™: Pectoralis majorMuscles Crossing the Shoulder JointFour muscles are rotator cuff musclesSupraspinatusInfraspinatusTeres minorSubscapularis Reinforce the capsule of the shoulderAct as synergists and fixatorsTwo additional muscles are synergists: coracobrachialis and teres majorMuscles Crossing the Shoulder JointPLAYA&P Flix™: Movement from the rotator cuff muscles (a)PLAYA&P Flix™: Muscles that cross the glenohumeral jointPLAYA&P Flix™: Movement from the rotator cuff muscles (b)PLAYA&P Flix™: Teres MajorRotator Cuff Anatomy and FunctionPLAYA&P Flix™: SupraspinatusPLAYA&P Flix™: SubscapularisPLAYA&P Flix™: InfraspinatusPLAYA&P Flix™: Teres minorPLAYA&P Flix™: Rotator cuff musclesFigure 10.14aClavicleDeltoidSternumPectoralis majorLateral headLong headMedial headCoracobrachialisTriceps brachii:Biceps brachiiBrachialisBrachioradialis(a) Anterior viewRotator Cuff Anatomy and FunctionPLAYA&P Flix™: Axial muscles of the glenohumeral joint (a)PLAYA&P Flix™: Scapular muscles of the glenohumeral joint (a)Figure 10.14bSupraspinatus*Spine of scapula(b) Posterior viewDeltoid (cut)Greater tubercleof humerusInfraspinatus*Teres minor*Teres majorTriceps brachii:Latissimus dorsiHumerusOlecranon processof ulna Lateral head Long headAnconeus* Rotator cuff musclesRotator Cuff Anatomy and FunctionPLAYA&P Flix™: Scapular muscles of the glenohumeral joint (b)PLAYA&P Flix™: Axial muscles of the glenohumeral joint (b)Table 10.12 Part 1PLAYA&P Flix™: Movement at the glenohumeral joint (a)PLAYA&P Flix™: Movement at the glenohumeral joint: An overviewPLAYA&P Flix™: Movement at the glenohumeral joint (b)Movement at the Glenohumeral JointPLAYA&P Flix™: Muscles of the elbow joint (a)PLAYA&P Flix™: The elbow joint and forearm: An overviewMuscles Crossing the Elbow JointAnterior flexor musclesBrachialis and biceps brachii—chief forearm flexorsBrachioradialis—synergist and stabilizerFigure 10.14aClavicleDeltoidSternumPectoralis majorLateral headLong headMedial headCoracobrachialisTriceps brachii:Biceps brachiiBrachialisBrachioradialis(a) Anterior viewMuscles Crossing the Elbow JointPLAYA&P Flix™: Biceps brachiiPLAYA&P Flix™: Muscles of the elbow joint (b)PLAYA&P Flix™: BrachialisPLAYA&P Flix™: BrachioradialisMuscles Crossing the Elbow JointPosterior extensor musclesTriceps brachii—prime mover of forearm extensionAnconeus—weak synergistFigure 10.14bSupraspinatus*Spine of scapula(b) Posterior viewDeltoid (cut)Greater tubercleof humerusInfraspinatus*Teres minor*Teres majorTriceps brachii:Latissimus dorsiHumerusOlecranon processof ulna Lateral head Long headAnconeus* Rotator cuff musclesMuscles Crossing the Elbow JointPLAYA&P Flix™: Triceps brachiiPLAYA&P Flix™: Muscles of the elbow joint (c)Figure 10.17aPLAYA&P Flix™: Movement at the elbow jointTricepsbrachiiLateralheadHumerusLongheadMedialhead(a)BrachialisShort headLong head(a) Muscles of the armExtensorsFlexorsOthersPosteriorcompartmentof arm (extendselbow); innervation:radial nerveBiceps brachiiAnterior compartment of arm (flexes elbow); innervation:musculocutaneous nerveTable 10.12 Part 2Muscles of the ForearmActions: movements of the wrist, hand, and fingers Most anterior muscles are flexors and insert via the flexor retinaculumMost posterior muscles are extensors and insert via the extensor retinaculumPLAYA&P Flix™: Muscles that act on the wrist  and fingers: An overviewPLAYA&P Flix™: Muscles of the forearm (a)Muscles of the ForearmSome forearm muscles act to produce pronation and supination of the forearmMuscles of the ForearmPronators: pronator teres and pronator quadratusSupinator: a synergist with the biceps brachiiPLAYA&P Flix™: Pronator teresPLAYA&P Flix™: Muscles of the forearm (c)PLAYA&P Flix™: Muscles of the forearm (b)PLAYA&P Flix™: SupinatorMuscles of the Forearm: Anterior CompartmentFlexorsFlexor carpi radialisPalmaris longusFlexor carpi ulnarisFlexor digitorum muscles (superficialis and profundus)Flexor pollicis longusPLAYA&P Flix™: Carpal tunnelFigure 10.15aBiceps brachiiTendon of biceps brachiiPronator teresBrachioradialisExtensor carpi radialis longusFlexor pollicis longusPronator quadratusFlexor retinaculumMedial head oftriceps brachiiMedial epicondyleof humerusFlexor carpi radialisPalmar aponeurosisSuperficial transverseligament of palmPalmaris longusFlexor carpi ulnarisFlexor digitorumsuperficialis(a)Muscles of the Forearm: Anterior CompartmentPLAYA&P Flix™: Flexor carpi ulnarisPLAYA&P Flix™: Flexor carpi radialisPLAYA&P Flix™: Anterior Muscles of the wrist and fingers (b)PLAYA&P Flix™: Flexor digitorum superificalisFigure 10.15cSupinatorTendon of flexorcarpi ulnaris (cut) Tendon of flexordigitorum profundus Flexor pollicis longusThenar muscles of thumbTendon of flexorpollicis longusLumbricalsTendon of flexor digitorumsuperficialis (cut) Pronator quadratusFlexor digitorumprofundus(c)Muscles of the Forearm: Anterior CompartmentPLAYA&P Flix™: Anterior Muscles of the wrist and fingers (a)Muscles of the Forearm: Posterior CompartmentExtensorsExtensor carpi radialis longus and brevisExtensor digitorumExtensor carpi ulnarisExtensor pollicis brevis and longusExtensor indicisAbductor pollicis longusFigure 10.16aInsertion oftriceps brachiiAnconeusFlexor carpiulnaris Extensor carpiulnarisExtensor digitiminimi Extensor indicisTendons of extensor carpiradialis brevis and longus Extensorexpansion (a)Extensor pollicislongusExtensor pollicisbrevisAbductorpollicis longusExtensor digitorumExtensor carpiradialis brevisExtensor carpiradialis longusBrachioradialisTendons ofextensordigitorumMuscles of the Forearm: Posterior CompartmentPLAYA&P Flix™: Extensor carpi radialis longusPLAYA&P Flix™: Posterior Muscles of the wrist and fingers (b)PLAYA&P Flix™: Extensor carpi radialis brevisPLAYA&P Flix™: Extensor digitorumPLAYA&P Flix™: Extensor carpi ulnaris(c)Figure 10.16bOlecranon process of ulnaInterosseiAnconeusSupinatorAbductor pollicis longusExtensor pollicis longusExtensor pollicis brevisExtensor indicis(b)Muscles of the Forearm: Posterior CompartmentPLAYA&P Flix™: Posterior Muscles of the wrist and fingers (a)Movements of the Wrist and Fingers Flexion and extension Abduction and adductionPLAYA&P Flix™: Movements of the wrist and fingers (b)PLAYA&P Flix™: Movements of the wrist and fingers (a)Figure 10.17bExtensorsFlexorsOthers(b)FlexorsExtensorsUlnaPosterior compartment of forearm(extends wrist and fingers);innervation: radial nerveOthersRadiusPronatorteres Brachioradialis(elbow flexor)Abductorpollicis longus(b) Muscles of the forearmAnterior compartment of forearm (flexes wrist and fingers); innervation: median or ulnar nerveFigure 10.12 Part 3Intrinsic Muscles of the HandSmall weak musclesLie entirely within the palm of the hand Control precise movements of metacarpals and fingers (e.g., threading a needle)Abductors and adductors of the fingersProduce opposition—move the thumb toward the little fingerFinger and Thumb MovementsFlexionThumb—bends medially along the palmFingers—bend anteriorlyExtensionThumb—points laterallyFingers—move posteriorlyIntrinsic Muscles of the HandThree groupsThenar eminence (ball of the thumb) Hypothenar eminence (ball of the little finger) Each of the above groups has a flexor, an abductor, and an opponens muscleMidpalmar muscles: lumbricals and palmar and dorsal interossei extend the fingersInterossei muscles also abduct and adduct the fingersFigure 10.18aFlexor digitorumprofundusTendons of:Flexor digitorumsuperficialisThirdlumbricalFourthlumbricalOpponensdigiti minimiFlexor digitiminimi brevisAbductordigiti minimiPisiform boneFlexor carpiulnaris tendonFlexor digitorumsuperficialistendonsFlexor pollicis longusFlexor carpi radialisPalmaris longusFlexor retinaculumAbductor pollicislongusOpponens pollicisAbductor pollicisbrevisFlexor pollicisbrevisAdductor pollicisDorsal interosseiFirst lumbricalSecond lumbricalFibrous sheath(a) First superficial layerTendons of:Figure 10.18bFlexor digitorumprofundus tendonFlexor digitorumsuperficialis tendonPalmar interosseiOpponens digitiminimi Flexor digiti minimibrevis (cut) Abductor digiti minimi(cut)Flexor pollicis longustendon Opponens pollicisAbductor pollicisbrevisFlexor pollicisbrevisAdductor pollicisDorsal interossei(b) Second layerFigure 10.18cPalmar interossei(c) Palmar interossei (isolated)Figure 10.18dDorsal interossei(d) Dorsal interossei (isolated)Intrinsic Muscles of the HandPLAYAnimation: Rotatable hand