Experimental Manualof HumanAnatomyStructuraldifferences betweenthepelvisofan adultmale andfemalereflectthefemale'sfunctionof pregnancy and parturition. Afemale pelvic bone is usually lighter and thinner, and has a smallerobturatorforamen and acetabulum thanamale one.Thefemalepelvic cavityis wider in alldiameters.The distances between the ischial spines and ischial tuberosities are also greater thanthose in a male. In the female, the pelvic inlet is round or oval and has an obliquity of about 6oo, itspelvic outlet is wider than that of the male. The sacral curvature is bent more sharply posteriorlythan in a male.The subpubic angle is narrow in a male(700-75°), but much wider inthe female(900100°). The pubic symphsis pubis is shallower and shorter in the female than in the male.2.Articulations of free lower limbThe articulations of the free upper limb include the hip joint, the knee joint, the joints betweenthetibiaandfibula,andthe jointsofthefoot(1) Hip jointThe hip join is a typical ball and socket synovial joint, formed by the head of the femur and theacetabulum of hipbone.Thefibrocartilageattached tothemargin of the acetabulum is called theacetabular labrum.Itdeepens the socket of acetabulum and protects theedge of the bone.Theacetabular labrum is an incomplete ring connecting by the transverse acetabular ligamentinferiorly.Thearticularcartilage on thefemoral head coversthe entire surfaceexceptforthefoveacapitis femoris.The articular capsuleis strong and dense.Aboveit isattachedtothemargin oftheacetabulum and the transverse ligament. Below, it surrounds the neck of the femur, and is attached.in front, tothe intertrochanteric line,behind to only the upper 2/3parts of the neck.Fracture at theneck of the femur may be intra or extra capsular, depending on whether it occurs above or belowthe attachment of the capsule.The capsule is strengthened by a number of ligaments. The iliofemoral ligament is the mostimportant and the strongest. It lies in front of the Joint, and is frequently called the Y-shaped(inverted) ligament. Above, its stem is attached to the lower part of the anterior inferior iliac spine;its two limbs pass downward tobe attached along the intertrochanteric line.It has an important role36
Experimental Manual of Human Anatomy 36 Structural differences between the pelvis of an adult male and female reflect the female's function of pregnancy and parturition. A female pelvic bone is usually lighter and thinner, and has a smaller obturator foramen and acetabulum than a male one. The female pelvic cavity is wider in all diameters. The distances between the ischial spines and ischial tuberosities are also greater than those in a male. In the female, the pelvic inlet is round or oval and has an obliquity of about 600 ; its pelvic outlet is wider than that of the male. The sacral curvature is bent more sharply posteriorly than in a male. The subpubic angle is narrow in a male (700 -750 ), but much wider in the female (900 - 1000 ). The pubic symphsis pubis is shallower and shorter in the female than in the male. 2. Articulations of free lower limb The articulations of the free upper limb include the hip joint, the knee joint, the joints between the tibia and fibula, and the joints of the foot. (1) Hip joint The hip join is a typical ball and socket synovial joint, formed by the head of the femur and the acetabulum of hip bone. The fibrocartilage attached to the margin of the acetabulum is called the acetabular labrum. It deepens the socket of acetabulum and protects the edge of the bone. The acetabular labrum is an incomplete ring connecting by the transverse acetabular ligament inferiorly. The articular cartilage on the femoral head covers the entire surface except for the fovea capitis femoris. The articular capsule is strong and dense. Above it is attached to the margin of the acetabulum and the transverse ligament. Below, it surrounds the neck of the femur, and is attached, in front, to the intertrochanteric line, behind to only the upper 2/3 parts of the neck. Fracture at the neck of the femur may be intra or extra capsular, depending on whether it occurs above or below the attachment of the capsule. The capsule is strengthened by a number of ligaments. The iliofemoral ligament is the most important and the strongest. It lies in front of the Joint, and is frequently called the Y-shaped (inverted) ligament. Above, its stem is attached to the lower part of the anterior inferior iliac spine; its two limbs pass downward to be attached along the intertrochanteric line. It has an important role
ExperimentalManualofHumanAnatomyin maintaining the erect posture of the body.The ligament ofthe head of the femur is intracapsularand passes from the acetabular notch and transverse ligament into the fovea on the head offemur,along it runs an artery,which supplies a small area ofthe femoral head adjacent to the attachmentof the ligament. The ligament is tense when the thigh is semiflexed and the limb adducted .Thepubofemoral ligament is attached to the ramus of the pubis and blends with the capsule. Thisligament limits abduction and lateral rotation ofthe joint.The ischiofemoral ligament springs fromthe ischium below the acetabulum and blends with the circular fibers of the capsule. It limitsadductionof the joint.Thetransverse acetabular ligament is aportionof theacetabular labrum infact. Its flattened fibers cross the acetabular notch and concert it into a foramen through which thenutrient vessels enter the joint.The zona orbicularis are circularfibers and forma collar around theneck of thefemur tohelpholdthehead inthe acetabulumThehip joint is capableofflexion,extension,abduction,adduction,circumduction and rotation(2) KneejointThe knee joint is the largest and the most complicated joint in the body. It is formed by the medialand lateral condyles of femurandtibia,thepatellaand thepatellasurfaceof femur.Sincethearticular surfaces of thecomponentbonesarenot adapted to each other,thekneejoint hasto dependontheaccessory structurestomaintain its stabilityThearticular capsuleof the joint is attachedto theborders ofthearticular surfaces ofthebonycomponents and the menisci. It is strengthened in almost its entire and is inseparable from themAnteriorly,thepatellar ligament is the continuation of thetendon of the quadriceps femorisPosteriorly,theobliquepopliteal ligamentspringsfromthemedial condyleofthetibia and crosseslaterally and superiorly to thelateral condyleofthefemur.Medially,the tibial collateral ligament isa flat band that extends from the tubercle on the medial condyle of the femur to the medial condyleand themedial surface of the body ofthe tibia.Its deep surface is intimately adherentto the capsuleand the medial meniscus. Laterally, the fibular collateral ligament, a rounded fibrous cord, isattached above to the back part of the lateral condyle of the femur and below to the lateral side of37
Experimental Manual of Human Anatomy 37 in maintaining the erect posture of the body. The ligament of the head of the femur is intracapsular, and passes from the acetabular notch and transverse ligament into the fovea on the head of femur, along it runs an artery, which supplies a small area of the femoral head adjacent to the attachment of the ligament. The ligament is tense when the thigh is semiflexed and the limb adducted .The pubofemoral ligament is attached to the ramus of the pubis and blends with the capsule. This ligament limits abduction and lateral rotation of the joint. The ischiofemoral ligament springs from the ischium below the acetabulum and blends with the circular fibers of the capsule. It limits adduction of the joint. The transverse acetabular ligament is a portion of the acetabular labrum in fact. Its flattened fibers cross the acetabular notch and concert it into a foramen through which the nutrient vessels enter the joint. The zona orbicularis are circular fibers and form a collar around the neck of the femur to help hold the head in the acetabulum. The hip joint is capable of flexion, extension, abduction, adduction, circumduction and rotation. (2) Knee joint The knee joint is the largest and the most complicated joint in the body. It is formed by the medial and lateral condyles of femur and tibia, the patella and the patella surface of femur. Since the articular surfaces of the component bones are not adapted to each other, the knee joint has to depend on the accessory structures to maintain its stability. The articular capsule of the joint is attached to the borders of the articular surfaces of the bony components and the menisci. It is strengthened in almost its entire and is inseparable from them. Anteriorly, the patellar ligament is the continuation of the tendon of the quadriceps femoris. Posteriorly, the oblique popliteal ligament springs from the medial condyle of the tibia and crosses laterally and superiorly to the lateral condyle of the femur. Medially, the tibial collateral ligament is a flat band that extends from the tubercle on the medial condyle of the femur to the medial condyle and the medial surface of the body of the tibia. Its deep surface is intimately adherent to the capsule and the medial meniscus. Laterally, the fibular collateral ligament, a rounded fibrous cord, is attached above to the back part of the lateral condyle of the femur and below to the lateral side of
Experimental Manualof HumanAnatomythe headofthefibula.And isfreeto articular capsule.Boththetibial andfibularcollateral ligamentsbecometaut inextension and loose inflexion.Thecruciateligamentsconsist of the anterior cruciateligament and posterior cruciate ligaments. They lie within the capsule of the knee Joint and are apair of strong cords crossing each other like the limbs of an “X".The anterior cruciate ligamentprevents anterior displacement ofthe tibia and becomes taut in full extension. The posterior cruciateligament preventstibiafromposteriordisplacementand becomestaut in all positionsofflexionThe menisci aretwo crescent shaped wafers offibrocartilage,which serve to deepen the surface ofthe head of the tibia for articulation with the condyles ofthe femur. They play an important role inimproving the congruity of the articular surfaces. The lateral meniscus is more nearly circular andcovers a somewhat greater proportion of the tibial surface than does the medial meniscus. Themedial meniscus is larger and is nearly semicircular in outline.The lateral margin of it is firmlyfixed to the articular capsule and the tibial collateral ligament. This accounts for the more frequentincidence of injury to the medial than the lateral meniscus. Sprains of the tibial collateral ligamentmaytearthecartilageordetach itfromthearticularcapsuleTheknee joint isprimarilya hinge joint and its principal movements areflexion and extensionIn semi flexed position, the joint allows slight abduction and adduction, and some rotationof theleg.(3) Articulations between tibia and fibulaThetibia and fibula are connected by the tibiofibular articulation, the interosseous membrane andthe tibiofibularsyndesmosis.The proximal tibiofibular joint is an arthrodial joint between the lateralcondyle ofthetibia and theheadof thefibula.Thedistal tibiofibular syndesmosis isformedbythesurface ofthelower end of thefibula and tibia,and strengthenedbythe anterior,posterior andinterosseous ligaments. A very strong interosseous membrane extends between the interosseouscrests of thetibia and fibula(4) Joints of theFootThe joints offoot include six part: the ankle joint, the intertarsal joints, the tarsometatarsal joint38
Experimental Manual of Human Anatomy 38 the head of the fibula. And is free to articular capsule. Both the tibial and fibular collateral ligaments become taut in extension and loose in flexion. The cruciate ligaments consist of the anterior cruciate ligament and posterior cruciate ligaments. They lie within the capsule of the knee Joint and are a pair of strong cords crossing each other like the limbs of an “X". The anterior cruciate ligament prevents anterior displacement of the tibia and becomes taut in full extension. The posterior cruciate ligament prevents tibia from posterior displacement and becomes taut in all positions of flexion. The menisci are two crescent shaped wafers of fibrocartilage, which serve to deepen the surface of the head of the tibia for articulation with the condyles of the femur. They play an important role in improving the congruity of the articular surfaces. The lateral meniscus is more nearly circular and covers a somewhat greater proportion of the tibial surface than does the medial meniscus. The medial meniscus is larger and is nearly semicircular in outline. The lateral margin of it is firmly fixed to the articular capsule and the tibial collateral ligament. This accounts for the more frequent incidence of injury to the medial than the lateral meniscus. Sprains of the tibial collateral ligament may tear the cartilage or detach it from the articular capsule. The knee joint is primarily a hinge joint and its principal movements are flexion and extension. In semi flexed position, the joint allows slight abduction and adduction, and some rotation of the leg. (3) Articulations between tibia and fibula The tibia and fibula are connected by the tibiofibular articulation, the interosseous membrane and the tibiofibular syndesmosis. The proximal tibiofibular joint is an arthrodial joint between the lateral condyle of the tibia and the head of the fibula. The distal tibiofibular syndesmosis is formed by the surface of the lower end of the fibula and tibia, and strengthened by the anterior, posterior and interosseous ligaments. A very strong interosseous membrane extends between the interosseous crests of the tibia and fibula. (4) Joints of the Foot The joints of foot include six part: the ankle joint, the intertarsal joints, the tarsometatarsal joint
ExperimentalManualofHumanAnatomythe intermetatarsal joints, the metatarsophalangeal Joints and the interphalangeal joints.The ankle joint or talocrural joint is a hinge joint which is formed by the distal ends of the tibiaandfibulawiththetrochleaofthetalus.The articularcapsule surrounds the joints ofthethreebonesthe anteriorandposteriorparts of the capsule are verythin and loose.There arethree ligamentssupporting the ankle joint on the outside of the capsule. The strong medial or deltoid ligament isassociated withthe tibia.From the tip of the medial malleolus, it extendsto the navicular bone, talusand calcaneusbones of thefoot.Thelateral collateral ligaments consist of theanterioretalofibularligament,posteriortalofibularligamentandcalcaneofibularligament.Theyextendfromthelateralmalleolus to the talus and the calcaneus respectivelyThemovementsof the jointaredorsiflexionandplantarflexion.Thetrochleaofthetalus is wideInfrontthan behind,in dorsiflexion,theebroaderportion ofthetrochlea occupiesand completelyfills the socket of the Joint, so that the position of dorsiflexion of the joint is more stable than thepositionof planterflexion.The intertarsal joints include several jointsthemost importantofthesejoints arethe subtalar jointthe talocalcaneonavicular joint and the calca-neocuboid joint.Thetransverse tarsal joint or Chopartjoint, is composed ofthe talonavicular joint medially and the calcaneocuboid joint laterally.Thesejoints are separatebut combinein a distinctive movement pattern responsible forthe action ofinversion and eversion ofthefoot.Inversion is accompaniedbyadduction andplantarflexion,whileeversion is accompanied by abduction and dorsiflexion. The movements of the subtalar and thetalocalcaneonavicular jointsallowthefoottobeplaced firmlyon slantingand irregular surfaces andstill serve as a firmbasis of supportfor the body.Many strong ligaments are concerned inmaintaining the stability of joints.In order to resist the stress of the body weight, the plantarligaments are much stronger than the dorsal. The chief ligaments of these joints are the plantarcalcaneonaviclar ligament or spring ligament, which supports the inferior surfaceofthe head ofthstalus, the bifurcate ligament, which is "Y" shaped and extends from the calcaneus to the navicularand cuboid; the long plantar ligament, with its deeper fibers stretching from the plantar surface of39
Experimental Manual of Human Anatomy 39 the intermetatarsal joints, the metatarsophalangeal Joints and the interphalangeal joints. The ankle joint or talocrural joint is a hinge joint which is formed by the distal ends of the tibia and fibula with the trochlea of the talus. The articular capsule surrounds the joints of the three bones: the anterior and posterior parts of the capsule are very thin and loose. There are three ligaments supporting the ankle joint on the outside of the capsule. The strong medial or deltoid ligament is associated with the tibia. From the tip of the medial malleolus, it extends to the navicular bone, talus and calcaneus bones of the foot. The lateral collateral ligaments consist of the anterior etalofibular ligament, posterior talofibular ligament and calcaneofibular ligament. They extend from the lateral malleolus to the talus and the calcaneus respectively. The movements of the joint are dorsiflexion and plantar flexion. The trochlea of the talus is wider In front than behind; in dorsiflexion, thee broader portion of the trochlea occupies and completely fills the socket of the Joint, so that the position of dorsiflexion of the joint is more stable than the position of planter flexion. The intertarsal joints include several joints the most important of these joints are the subtalar joint, the talocalcaneonavicular joint and the calca-neocuboid joint. The transverse tarsal joint or Chopart joint, is composed of the talonavicular joint medially and the calcaneocuboid joint laterally. These joints are separate but combine in a distinctive movement pattern responsible for the action of inversion and eversion of the foot. Inversion is accompanied by adduction and plantar flexion, while eversion is accompanied by abduction and dorsiflexion. The movements of the subtalar and the talocalcaneonavicular joints allow the foot to be placed firmly on slanting and irregular surfaces and still serve as a firm basis of support for the body. Many strong ligaments are concerned in maintaining the stability of joints. In order to resist the stress of the body weight, the plantar ligaments are much stronger than the dorsal. The chief ligaments of these joints are the plantar calcaneonaviclar ligament or spring ligament, which supports the inferior surface of the head of the talus; the bifurcate ligament, which is " Y" shaped and extends from the calcaneus to the navicular and cuboid; the long plantar ligament, with its deeper fibers stretching from the plantar surface of
ExperimentalManualofHumanAnatomythecalcaneustothetuberosityofthe cuboidbone,and itsmore superficialfiberstothebases ofthethird, fourth and fifth metatarsal bones. These ligaments play an important role in maintaining thelongitudinal arch of the foot.The tarsometatarsal joints (or Lisfrance's joint)are plane synovial joints between the adjacentsurfaces ofthe distal rowoftarsal bones and the bases ofthe metatarsal bones. Movements permittedat these joints are limited to a slight gliding of the bones upon each other.The intermetatarsal joints areplanearticulations and unite the bases ofthemetatarsal bones.Themovement permitted is limited to a slight glidingThe metatarsophalangeal joints are ellipsoid articulations between the rounded head of themetatarsal bonesand thebasesof theproximalphalanges.Themovements of the jointsareflexionextension, abduction and adductionThe interphalangeal joints are similar to the metatarsophalangeal joints except that their trochlearsurfaces permit only dorsiflexion and plantar flexion(5)ArchesofFootThearrangement of bonesofthefootforms medial and lateral longitudinal arches andtransversearcheswhich enablethe footto support thebodyweight and provideleverage while walking.Thearches of the foot are completed and maintained by strong ligaments and tendons.The ligamentsare primarily in static standing, but the muscular support of the foot becomes significant both in theminor movements of the erect posture and the more extensive bodily actions. If they are weakenedit may result in flat foot.(Mei Yang)Chapter 5 SkullLearning Objectives:1.Comprehend theformation,division andfunction oftheskull2.Identify the bony landmarks in both the internal and external views of the skull base3.Describe the structures ofthe orbit, the bony nasal cavity and the paranasal sinuses40
Experimental Manual of Human Anatomy 40 the calcaneus to the tuberosity of the cuboid bone, and its more superficial fibers to the bases of the third, fourth and fifth metatarsal bones. These ligaments play an important role in maintaining the longitudinal arch of the foot. The tarsometatarsal joints (or Lisfrance's joint) are plane synovial joints between the adjacent surfaces of the distal row of tarsal bones and the bases of the metatarsal bones. Movements permitted at these joints are limited to a slight gliding of the bones upon each other. The intermetatarsal joints are plane articulations and unite the bases of the metatarsal bones. The movement permitted is limited to a slight gliding. The metatarsophalangeal joints are ellipsoid articulations between the rounded head of the metatarsal bones and the bases of the proximal phalanges. The movements of the joints are flexion, extension, abduction and adduction. The interphalangeal joints are similar to the metatarsophalangeal joints except that their trochlear surfaces permit only dorsiflexion and plantar flexion. (5) Arches of Foot The arrangement of bones of the foot forms medial and lateral longitudinal arches and transverse arches which enable the foot to support the body weight and provide leverage while walking. The arches of the foot are completed and maintained by strong ligaments and tendons. The ligaments are primarily in static standing, but the muscular support of the foot becomes significant both in the minor movements of the erect posture and the more extensive bodily actions. If they are weakened, it may result in flat foot. (Mei Yang) Chapter 5 Skull Learning Objectives: 1. Comprehend the formation, division and function of the skull. 2. Identify the bony landmarks in both the internal and external views of the skull base. 3. Describe the structures of the orbit, the bony nasal cavity and the paranasal sinuses