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

10 The Muscular System: Part DMuscles Crossing Hip and Knee JointsMost anterior muscles flex the femur at the hip and extend the leg at the knee (foreswing of walking)Most posterior muscles extend the thigh and flex the leg (backswing of walking)Medial muscles all adduct the thighAll three groups are enclosed by the fascia lataPLAYA&P Flix™: Muscles that act on the hip joint and femur: An overviewMovements of the Thigh Include flexion, extension, abduction, adduction, circumduction, and rotationThigh flexors pass in front of the hip jointIliopsoas (iliacus and psoas major): prime mover of flexionTensor fasciae lataeRectus femorisAssisted by medial adductors and sartorius PLAYA&P Flix™: Anterior muscles that cross the hip jointFigure 10.19aPsoas minorIliac crestPsoas majorIliopsoas12th ribQuadratus lumborumIliacusAnterior superior iliac spineTensor fasciae lataePectineusSartoriusQuadriceps femoris• Rectus femoris • Vastus lateralis• Vastus medialis(a)Adductor magnusPatellaPatellar ligamentTendon of quadriceps femoris12th thoracic vertebra5th lumbar vertebraAdductor longusGracilisMovements of the ThighPLAYA&P Flix™: Tensor fasciae lataePLAYA&P Flix™: IliopsoasPLAYA&P Flix™: Rectus femorisPLAYA&P Flix™: SartoriusMovements of the ThighThigh extensorsHamstring muscles (prime movers of extension)Biceps femorisSemitendinosusSemimembranosus Gluteus maximus (prime mover during forceful extension)Figure 10.20aGluteus mediusGluteus maximusAdductor magnusGracilisIliotibial tractLong headSemitendinosusSemimembranosusShort headBicepsfemorisHamstrings(a)Movements of the ThighPLAYA&P Flix™: SemitendinosusPLAYA&P Flix™: Biceps femorisPLAYA&P Flix™: SemimembranosusMovements of the Thigh Adductors (also medially rotate thigh)Adductor magnusAdductor longusAdductor brevisPectineusGracilisPLAYA&P Flix™: Medial muscles that cross the hip jointFigure 10.19b(b)O = origin I = insertionAdductormagnusPectineus(cut)AdductorbrevisAdductorlongusFemurPLAYA&P Flix™: PectineusMovements of the Thigh AbductorsGluteus maximus (also laterally rotates thigh)Gluteus medius (also medially rotates thigh)Gluteus minimus (also medially rotates thigh)Piriformis (also laterally rotates thigh)Obturator externus (also laterally rotates thigh)Obturator internus (also laterally rotates thigh)Gemellus (also laterally rotates thigh)PLAYA&P Flix™: Posterior muscles that cross the hip jointFigure 10.20cSuperiorgemellusObturatorinternusInferiorgemellusGluteus medius (cut) Gluteus minimusPiriformisObturatorexternusQuadratusfemorisGluteusmaximus(cut)(c)Movements of the Thigh PLAYA&P Flix™: Gluteus mediusPLAYA&P Flix™: Gluteus maximus(c)Summary of Movement at the Hip JointPLAYA&P Flix™: Movement at the hip jointMuscles of the Thigh that Move the Knee JointQuadriceps femoris—sole extensor of the knee Hamstring muscles—flex the knee, and are antagonists to the quadriceps femorisPLAYA&P Flix™: Muscles that cross the knee joint: An overview.Figure 10.19aPsoas minorIliac crestPsoas majorIliopsoas12th ribQuadratus lumborumIliacusAnterior superior iliac spineTensor fasciae lataePectineusSartoriusQuadriceps femoris• Rectus femoris • Vastus lateralis• Vastus medialis(a)Adductor magnusPatellaPatellar ligamentTendon of quadriceps femoris12th thoracic vertebra5th lumbar vertebraAdductor longusGracilisPLAYA&P Flix™: Movement at the hip jointMuscles of the Thigh that Move the Knee JointPLAYA&P Flix™: Rectus femorisPLAYA&P Flix™: Anterior extensors that act on the kneePLAYA&P Flix™: Vastus lateralisPLAYA&P Flix™: Vastus medialisPLAYA&P Flix™: Vastus intermediusFigure 10.20aGluteus mediusGluteus maximusAdductor magnusGracilisIliotibial tractLong headSemitendinosusSemimembranosusShort headBicepsfemorisHamstrings(a)PLAYA&P Flix™: Movement at the hip jointMuscles of the Thigh that Move the Knee JointPLAYA&P Flix™: Biceps femorisPLAYA&P Flix™: Posterior flexors that act on the kneePLAYA&P Flix™: SemitendinosusPLAYA&P Flix™: SemimembranosusSummary of Movement at the Knee JointPLAYA&P Flix™: Movement at the knee jointFascia of the LegA deep fascia of the leg is continuous with the fascia lataThis fascia segregates the leg into three compartments: anterior, lateral, and posteriorDistally, the fascia thickens and forms the flexor, extensor, and fibular retinaculaePLAYA&P Flix™: Muscles that act on the ankle and foot: An overviewMuscles of the Leg: MovementsVarious leg muscles produce the following movementsAnkle—dorsiflexion and plantar flexionIntertarsal joints—inversion and eversion of the footToes—flexion and extensionPLAYA&P Flix™: Movements of the ankle and foot (a)Muscles of the Anterior Compartment of the LegPrimary toe extensors and ankle dorsiflexorsTibialis anteriorExtensor digitorum longusExtensor hallucis longusFibularis tertius (not always present)PLAYA&P Flix™: Anterior muscles that act on the ankle and footFigure 10.21aFibularis longusGastrocnemiusTibiaTibialis anteriorExtensor digitorum longusSoleusExtensor hallucis longusFibularis tertiusExtensor hallucis brevisExtensor digitorum brevisSuperior and inferiorextensor retinacula(a)Muscles of the Anterior Compartment ofthe LegPLAYA&P Flix™: Extensor digitorum longusPLAYA&P Flix™: Tibialis anteriorPLAYA&P Flix™: Extensor hallucis longusMuscles of the Lateral Compartment ofthe LegPlantar flexion and eversion of the footFibularis longus Fibularis brevisPLAYA&P Flix™: Lateral muscles that act on the ankle and footFigure 10.22aPatellaHead of fibulaGastrocnemiusSoleusFibularis longusExtensor digitorum longusTibialis anteriorExtensor hallucis longusFibularis tertiusFibularis brevisFlexor hallucis longusFibular retinaculumLateral malleolusSuperior and inferior extensorretinacula Extensor digitorum brevis5th metatarsalExtensor hallucis brevis(a)Muscles of the Lateral Compartment ofthe LegPLAYA&P Flix™: Fibularis longusMuscles of the Posterior Compartment of the LegFlexors of the foot and the toesGastrocnemiusSoleusPlantarisPopliteusTibialis posteriorFlexor digitorum longusFlexor hallucis longusMuscles of the Posterior Compartment of the LegPLAYA&P Flix™: Deep posterior muscles that act on the ankle and footPLAYA&P Flix™: Superficial muscles that act on the ankle and footFigure 10.23aGastrocnemiusPlantarisMedial headLateral headTendon ofgastrocnemiusCalcaneal tendon Medial malleolus Lateral malleolusCalcaneus(a) Superficial view of the posterior leg.Muscles of the Posterior Compartment of the LegPLAYA&P Flix™: SoleusPLAYA&P Flix™: GastrocnemiusFigure 10.23cGastrocnemiusmedial head (cut)Flexor digitorumlongusTendon of tibialisposterior Medial malleolusCalcaneal tendon (cut)CalcaneusFibularis brevisFlexor hallucis longusFibularis longusFibulaTibialis posteriorSoleus (cut)PopliteusGastrocnemiuslateral head (cut)Plantaris (cut)(c) The triceps surae has been removed to show the deep muscles of the posterior compartment.Muscles of the Posterior Compartment of the LegPLAYA&P Flix™: Flexor digitorum longusPLAYA&P Flix™: Tibialis posteriorPLAYA&P Flix™: Flexor hallucis longusMajor Actions of Muscles Acting on the Thigh, Leg, and FootView the next five slides for a summary of the major actions of the muscles acting on the thigh, leg, and footFigure 10.25aPosterior compartment ofthigh (flexes leg and extendsthigh); innervation: tibialnerve (portion of sciatic nerve)Medial compartment (adductsthigh); innervation: obturatornerve Anterior compartment (extends leg);innervated by femoral nerveVastusintermediusRectus femorisVastus medialis(a) Muscles of the thighPosteriorcompartmentmusclesAnteriorcompartmentmuscleMedialcompartmentmuscles of thighand lateralcompartmentmuscles of legAdductorsVastuslateralisHamstringsFemur(a)Figure 10.25bPosterior compartmentof leg (plantar flexes foot,flexes toes); innervatedby tibial nerveAnterior compartment of leg(dorsiflexes foot, extends toes);innervated by deep fibular nerveLateral compartment of leg(plantar flexes and everts foot);innervation: superficialfibular nerveTriceps suraeFibulaTibialisanteriorTibiaFibularismuscles(b) Muscles of the leg(b)PosteriorcompartmentmusclesAnteriorcompartmentmuscleMedialcompartmentmuscles of thighand lateralcompartmentmuscles of legPLAYA&P Flix™: Actions of the muscles of the lateral compartment of the legPLAYA&P Flix™: Actions of the muscles of the anterior compartment of the legPLAYA&P Flix™: Actions of the muscles of the posterior compartment of the legMajor Actions of Muscles Acting on the Ankle and FootTable 10.17 Part 1Table 10.17 Part 2Intrinsic Muscles of the FootHelp flex, extend, abduct, and adduct the toesSupport the arches of the foot along with some leg tendonsExtensor digitorum brevis—dorsal foot muscle that helps extend the toesFigure 10.21aFibularis longusGastrocnemiusTibiaTibialis anteriorExtensor digitorum longusSoleusExtensor hallucis longusFibularis tertiusExtensor hallucis brevisExtensor digitorum brevisSuperior and inferiorextensor retinacula(a)Plantar Muscles The plantar muscles occur in four layers Superficial layerFlexor digitorum brevisAbductor hallucisAbductor digiti minimi Second layerFlexor accessoriusLumbricalsFigure 10.24aTendon of flexor hallucis longusLumbricalsFlexor hallucis brevisFlexor digiti minimi brevisAbductor hallucisFlexor digitorum brevisFlexor accessoriusAbductor digiti minimiCalcaneal tuberosity(a) First layer (plantar aspect)Figure 10.24bLumbricalsFlexor hallucis brevisFlexor digitorum longus (tendon)Flexor digiti minimi brevisAbductor digiti minimiFlexor accessoriusFibularis longus (tendon)Flexor digitorum longus (tendon)Flexor hallucis longus (tendon)Flexor hallucis longus tendon(b) Second layer (plantar aspect) Plantar Muscles 3. Third layerFlexor hallucis brevisAdductor hallucisFlexor digiti minimi brevis4. Deepest layerPlantar and dorsal interosseiFigure 10.24cAdductor hallucis (transverse head) Adductor hallucis (oblique head) Interosseous musclesFlexor hallucis brevisFlexor digiti minimi brevisFibularis longus (tendon)Flexor accessoriusFlexor digitorum longus (tendon)Flexor hallucis longus (tendon)(c) Third layer (plantar aspect)Figure 10.24dPlantar interossei(d) Fourth layer (plantar aspect): plantar interosseiPLAYAnimation: Rotatable foot