1. Chapter 8 Lecture Outline Copyright (c) The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 8-1

2. 8-2 The Skeletal System overview of the skeleton the skull the vertebral column and thoracic cage the pectoral girdle and upper limb the pelvic girdle and lower limb Figure 8.1a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Skull Frontal bone Pectoral girdle Clavicle Maxilla Parietal bone Mandible Humerus Femur Fibula Ulna Radius Scapula Hip bone Sacrum Patella Carpus Thoracic cage Pelvis Sternum Ribs Costal cartilages Phalanges Metatarsal bones Phalanges Coccyx Vertebral column Metacarpal bones Tarsus (a) Anterior view Tibia

3. 8-3 Overview of the Skeleton two regions of the skeleton –axial skeleton – forms the central supporting axis of the body skull, auditory ossicles, hyoid bone, vertebral column, and thoracic cage (ribs and sternum) –appendicular skeleton – includes the bones of the upper limb and pectoral girdle, and the bones of the lower limb and pelvic girdle number of bones –206 in typical adult skeleton varies with development of sesamoid bones (patella) –bones that form within some tendons in response to stress varies with presence of sutural (wormian) bones in skull –extra bones that develop in skull suture lines –270 bones at birth, decreases with fusion surface markings defined in Table 8.2 –ridges, spines, bumps, depressions, canals, pores, slits, cavities, and articular surfaces

4. 8-4 Axial and Appendicular Skeleton axial skeleton is colored tan –skull, vertebrae, sternum, ribs, sacrum and hyoid appendicular skeleton is colored green –pectoral girdle –upper extremity –pelvic girdle –lower extremity Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Skull Frontal bone Clavicle Maxilla Parietal bone Mandible Occipital bone Mandible Humerus Femur Fibula Ulna Radius Scapula Clavicle Scapula Hip bone Sacrum Patella Carpus Pelvis Sternum Ribs Costal cartilages Phalanges Metatarsal bones Phalanges Coccyx (b) Posterior view Pectoral girdle Thoracic cage Vertebral column Metacarpal bones Tarsus (a) Anterior view Tibia Figure 8.1

5. 8-5 Anatomical Features of Bones Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sinuses Crest Foramen Fossae Head Tubercle Crest Tuberosity Line Head Fovea Trochanters Fossae (a) Skull (lateral view) Epicondyles Condyles Alveolus Spine Condyle Process Lines Meatus (b) Scapula (posterior view) (c) Femur (posterior view) (d) Humerus (anterior view) Process Spine Figure 8.2

6. 8-6 The Skull skull – the most complex part of the skeleton 22 bones joined together by sutures (immovable joints) 8 cranial bones surround cranial cavity which encloses the brain other cavities – orbits, nasal cavity, oral (buccal) cavity, middle-, and inner ear cavities, and paranasal sinuses paranasal sinuses – frontal, sphenoid, ethmoid, and maxillary –lined by mucous membrane and air-filled –lighten the anterior portion of the skull –act as chambers that add resonance to the voice foramina – holes that allow passage for nerves and blood vessels 14 facial bones support teeth, facial and jaw muscles

7. 8-7 Major Skull Cavities Figure 8.7 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Frontal bone Ethmoid bone Middle Superior Inferior Maxilla Nasal cavity Mandible Vomer Orbit Cranial cavity Nasal conchae Oral cavity Maxillary sinus Zygomatic bone Ethmoid air cells

8. 8-8 Cranial Fossa cranium (braincase) – protects the brain and associated sense organs –swelling of the brain inside the rigid cranium may force tissue through foramen magnum resulting in death –consists of two parts: the calvaria (skullcap) and the cranial base base is divided into three basins that comprise the cranial floor –anterior cranial fossa holds the frontal lobe of the brain –middle cranial fossa holds the temporal lobes of the brain –posterior cranial fossa contains the cerebellum Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Superior view Posterior cranial fossa Middle cranial fossa Anterior cranial fossa Cerebellum Temporal lobe Frontal lobe (b) Lateral view Anterior cranial fossa Middle cranial fossa Posterior cranial fossa Figure 8.9

9. 8-9 Frontal Bone forms forehead and part of the roof of the cranium coronal suture – posterior boundary of frontal bone supraorbital margin forms roof of the orbit supraorbital foramen provides passage for nerve, artery, and vein glabella – smooth area above root of the nose contains frontal sinus Figure 8.3 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Frontal bone Coronal suture Lacrimal bone Squamous suture Infraorbital foramen Vomer Mandible Sphenoid bone Ethmoid bone Nasal bone Zygomatic bone Maxilla Mental foramen Temporal bone Glabella Mental protuberance Parietal bone Middle nasal concha Inferior nasal concha Supraorbital margin Supraorbital foramen

10. 8-10 Parietal Bone form most of cranial roof and part of its lateral walls bordered by 4 sutures –sagittal – between parietal bones –coronal – at anterior margin –lambdoid – at posterior margin –squamous – at lateral border two temporal lines serve as attachment of the temporalis muscle Figure 8.4a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parietal bone Frontal bone Lambdoid suture Sphenoid bone Temporal bone Zygomatic process External acoustic meatus Mandible Temporal lines Coronal suture Ethmoid bone Lacrimal bone Nasal bone Infraorbital foramen Zygomatic bone Temporal process Zygomaticofacial foramen Maxilla Mental foramen Occipital bone Squamous suture Mandibular condyle Styloid process Mastoid process (a) Right lateral view Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Frontal bone Coronal suture Sagittal suture Sutural bone Parietal bone Parietal foramen Lambdoid suture Occipital bone Posterior Anterior Figure 8.6

11. 8-11 Temporal Bone lateral wall and part of floor of cranial cavity –squamous part encircled by squamous suture zygomatic process mandibular fossa –tympanic part external auditory meatus styloid process –mastoid part mastoid process –mastoiditis from ear infection mastoid notch stylomastoid foramen mastoid foramen Figure 8.4a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parietal bone Frontal bone Lambdoid suture Sphenoid bone Temporal bone Zygomatic process External acoustic meatus Mandible Temporal lines Coronal suture Ethmoid bone Lacrimal bone Nasal bone Infraorbital foramen Zygomatic bone Temporal process Zygomaticofacial foramen Maxilla Mental foramen Occipital bone Squamous suture Mandibular condyle Styloid process Mastoid process (a) Right lateral view

12. 8-12 Petrous Portion of Temporal Bone –petrous part part of cranial floor separates middle from posterior cranial fossa houses middle and inner ear cavities receptors for hearing and sense of balance internal auditory meatus - opening for CN VII (vestibulocochlear nerve) carotid canal jugular foramen Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (b) Superior view of cranial floor Cribriform foramina Crista galli Diploe (spongy bone) Sphenoid bone Temporal bone Parietal bone Occipital bone Sella turcica Frontal bone Optic foramen Foramen rotundum Foramen ovale Foramen spinosum Foramen magnum Jugular foramen Hypoglossal canal Internal acoustic meatus Groove for venous sinus Petrous part of temporal bone Cribriform plate of ethmoid bone Figure 8.5b

13. 8-13 Right Temporal Bone Mastoid part Mastoid process (a) Lateral surface (b) Medial surface Styloid process Squamous suture Styloid process Tympanic part Squamous part Squamous suture Zygomatic process Mandibular fossa Mastoid process Squamous part Petrous part Mastoid notch External acoustic meatus Zygomatic process Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Internal acoustic meatus Figure 8.10

14. 8-14 Occipital Bone rear and base of skull foramen magnum holds spinal cord basilar part skull rests on atlas at occipital condyles hypoglossal canal transmits hypoglossal nerve (CN XII) supplying tongue muscles condylar canal external occipital protuberance for nuchal ligament superior and inferior nuchal lines mark neck muscles Figure 8.5a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Zygomatic bone Lambdoid suture Foramen magnum Mastoid foramen Jugular foramen Stylomastoid foramen Carotid canal Intermaxillary suture Palatine bone Greater palatine foramen Medial pterygoid plate Lateral pterygoid plate Foramen ovale Foramen spinosum Foramen lacerum Incisive foramen Sphenoid bone Zygomatic arch Mandibular fossa Styloid process External acoustic meatus Mastoid process Mastoid notch Condylar canal Temporal bone Superior nuchal line Inferior nuchal line Occipital bone (a) Inferior view Parietal bone Occipital condyle Vomer Posterior nasal aperture Palatine process of maxilla Basilar part of occipital bone External occipital protuberance

15. Sphenoid Bone body greater wing lesser wing optic foramen anterior clinoid processes superior orbital fissure 8-15 Figure 8.5b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lesser wing Greater wing Foramen ovale Body Lateral pterygoid plate Medial pterygoid plate Pterygoid processes (b) Posterior view Dorsum sellae Foramen rotundum Superior orbital fissure Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (b) Superior view of cranial floor Cribriform foramina Crista galli Diploe (spongy bone) Sphenoid bone Temporal bone Parietal bone Occipital bone Sella turcica Frontal bone Optic foramen Foramen rotundum Foramen ovale Foramen spinosum Foramen magnum Jugular foramen Hypoglossal canal Internal acoustic meatus Groove for venous sinus Petrous part of temporal bone Cribriform plate of ethmoid bone Figure 8.11b

16. 8-16 Sphenoid Bone Figure 8.11a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Optic foramen Lesser wing Greater wing Sella turcica Dorsum sellae Foramen rotundum Hypophyseal fossa Foramen ovale Foramen spinosum (a) Superior view Anterior clinoid process Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (b) Superior view of cranial floor Cribriform foramina Crista galli Diploe (spongy bone) Sphenoid bone Temporal bone Parietal bone Occipital bone Sella turcica Frontal bone Optic foramen Foramen rotundum Foramen ovale Foramen spinosum Foramen magnum Jugular foramen Hypoglossal canal Internal acoustic meatus Groove for venous sinus Petrous part of temporal bone Cribriform plate of ethmoid bone Figure 8.5b foramen rotundum foramen ovale foramen lacerum posterior nasal apertures or choanae medial pterygoid plate lateral pterygoid plate sphenoid sinus

17. 8-17 Sphenoid Bone sphenoid sinus Figure 8.4b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Coronal suture Frontal bone Sphenoid sinus Frontal sinus Crista galli Parietal bone Temporal bone Internal acoustic meatus Jugular foramen Hypoglossal canal Mandibular foramen Styloid process Squamous suture Lambdoid suture Sella turcica Occipital bone Vomer Palatine bone Maxilla Mandible Mental spines Nasal bone (b) Median section Cribriform plate of ethmoid bone Perpendicular plate of ethmoid bone Palatine process of maxilla Figure 8.5a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Zygomatic bone Lambdoid suture Foramen magnum Mastoid foramen Jugular foramen Stylomastoid foramen Carotid canal Intermaxillary suture Palatine bone Greater palatine foramen Medial pterygoid plate Lateral pterygoid plate Foramen ovale Foramen spinosum Foramen lacerum Incisive foramen Sphenoid bone Zygomatic arch Mandibular fossa Styloid process External acoustic meatus Mastoid process Mastoid notch Condylar canal Temporal bone Superior nuchal line Inferior nuchal line Occipital bone (a) Inferior view Parietal bone Occipital condyle Vomer Posterior nasal aperture Palatine process of maxilla Basilar part of occipital bone External occipital protuberance

18. 8-18 Ethmoid Bone Figure 8.12 Supraorbital foramen Orbital plate of ethmoid bone Lacrimal bone Optic foramen Orbital plate of frontal bone Lesser wing of sphenoid bone Frontal process of maxilla Superior orbital fissure Roof of orbit Orbital process of palatine bone Orbital surface of maxilla Floor of orbit Medial wall Zygomatic process of frontal bone Greater wing of sphenoid bone Orbital surface of zygomatic bone Inferior orbital fissure Lateral wall of orbit Infraorbital foramen Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. between the eyes contributes to medial wall of orbit lateral walls and roof of nasal cavity, and nasal septum three major portions of this porous, delicate bone perpendicular plate forms superior two-thirds of nasal septum cribriform plate – forms roof of nasal cavity –crista galli – attachment point for meninges –cribriform (olfactory) foramina labyrinth – large mass on each side of perpendicular plate –ethmoid cells in the make up ethmoid sinuses –orbital plate Figure 8.14 Orbital plate Crista galli Cribriform plate Cribriform foramina Ethmoidal cells Perpendicular plate Superior nasal concha Middle nasal concha Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

19. 8-19 Ethmoid Bone superior and middle concha perpendicular plate of nasal septum Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Coronal suture Frontal bone Sphenoid sinus Frontal sinus Crista galli Parietal bone Temporal bone Internal acoustic meatus Jugular foramen Hypoglossal canal Mandibular foramen Styloid process Squamous suture Lambdoid suture Sella turcica Occipital bone Vomer Palatine bone Maxilla Mandible Mental spines Nasal bone (b) Median section Cribriform plate of ethmoid bone Perpendicular plate of ethmoid bone Palatine process of maxilla Frontal sinus Inferior Anterior nasal spine Maxilla Incisive foramen Lacrimal bone Nasal bone Nasal cartilages Superior Middle Sphenoid sinus Palatine bone Sphenoid bone Crista galli Sella turcica Cribriform plate Cribriform foramina Occipital bone Lip Frontal bone Incisor Nasal conchae: Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.4bFigure 8.13

20. Facial Bones facial bones (14)– those that have no direct contact with the brain or meninges –support the teeth –give shape and individuality to the face –form part of the orbital and nasal cavities –provide attachments for muscles of facial expression and mastication 2 maxillae2 nasal bones 2 palatine bones2 inferior nasal conchae 2 zygomatic bones1 vomer 2 lacrimal bones1 mandible 8-20

21. 8-21 Maxillary Bones largest facial bones forms upper jaw and meet each other at a median intermaxillary suture –alveolar processes are bony points between teeth –alveolus - sockets that hold teeth forms inferomedial wall of orbit –infraorbital foramen –inferior orbital fissure forms most of the hard palate –palatine process –palate – forms the roof of the mouth and floor of nasal cavity –incisive foramen –palate allows us to chew while breathing –cleft palate and cleft lip Figure 8.3 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Frontal bone Coronal suture Lacrimal bone Squamous suture Infraorbital foramen Vomer Mandible Sphenoid bone Ethmoid bone Nasal bone Zygomatic bone Maxilla Mental foramen Temporal bone Glabella Mental protuberance Parietal bone Middle nasal concha Inferior nasal concha Supraorbital margin Supraorbital foramen Figure 8.5a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lambdoid suture Foramen magnum Mastoid foramen Jugular foramen Stylomastoid foramen Carotid canal Intermaxillary suture Palatine bone Greater palatine foramen Medial pterygoid plate Lateral pterygoid plate Foramen ovale Foramen spinosum Foramen lacerum (a) Inferior view Palatine process of maxilla Basilar part of occipital bone External occipital protuberance Zygomatic bone Incisive foramen Sphenoid bone Zygomatic arch Mandibular fossa Styloid process External acoustic meatus Mastoid process Mastoid notch Condylar canal Temporal bone Superior nuchal line Inferior nuchal line Occipital bone Parietal bone Occipital condyle Vomer Posterior nasal aperture

22. 8-22 Location of Maxillary Sinus maxillary sinus fills maxillae bone larger in volume than frontal, sphenoid and ethmoid sinuses Figure 8.8 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sphenoid sinus Frontal sinus Ethmoid sinus Maxillary sinus Figure 8.8

23. Palatine Bones L-shaped bone form the posterior portion of the hard palate part of lateral nasal cavity wall part of the orbital floor greater palatine foramina Supraorbital foramen Orbital plate of ethmoid bone Lacrimal bone Optic foramen Orbital plate of frontal bone Lesser wing of sphenoid bone Frontal process of maxilla Superior orbital fissure Roof of orbit Orbital process of palatine bone Orbital surface of maxilla Floor of orbit Medial wall Zygomatic process of frontal bone Greater wing of sphenoid bone Orbital surface of zygomatic bone Inferior orbital fissure Lateral wall of orbit Infraorbital foramen Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.14 8-23 Frontal sinus Inferior Anterior nasal spine Maxilla Incisive foramen Lacrimal bone Nasal bone Nasal cartilages Superior Middle Sphenoid sinus Palatine bone Sphenoid bone Crista galli Sella turcica Cribriform plate Cribriform foramina Occipital bone Lip Frontal bone Incisor Nasal conchae: Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.13

24. 8-24 Zygomatic Bones forms angles of the cheekbones and part of lateral orbital wall zygomaticofacial foramen zygomatic arch is formed from temporal process of zygomatic bone and zygomatic process of temporal bone Figure 8.4a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parietal bone Frontal bone Lambdoid suture Sphenoid bone Temporal bone Zygomatic process External acoustic meatus Mandible Temporal lines Coronal suture Ethmoid bone Lacrimal bone Nasal bone Infraorbital foramen Zygomatic bone Temporal process Zygomaticofacial foramen Maxilla Mental foramen Occipital bone Squamous suture Mandibular condyle Styloid process Mastoid process (a) Right lateral view

25. 8-25 Lacrimal Bones form part of medial wall of each orbit smallest bone of skull lacrimal fossa houses lacrimal sac in life –tears collect in lacrimal sac and drain into nasal cavity Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parietal bone Frontal bone Lambdoid suture Sphenoid bone Temporal bone Zygomatic process External acoustic meatus Mandible Temporal lines Coronal suture Ethmoid bone Lacrimal bone Nasal bone Infraorbital foramen Zygomatic bone Temporal process Zygomaticofacial foramen Maxilla Mental foramen Occipital bone Squamous suture Mandibular condyle Styloid process Mastoid process (a) Right lateral view Figure 8.4a

26. 8-26 Nasal Bones forms bridge of nose supports cartilages that shape lower portion of the nose often fractured by blow to the nose Figure 8.3 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Frontal bone Coronal suture Lacrimal bone Squamous suture Infraorbital foramen Vomer Mandible Sphenoid bone Ethmoid bone Nasal bone Zygomatic bone Maxilla Mental foramen Temporal bone Glabella Mental protuberance Parietal bone Middle nasal concha Inferior nasal concha Supraorbital margin Supraorbital foramen

27. 8-27 Inferior Nasal Conchae three conchae in the nasal cavity –superior and middle are part of the ethmoid bone inferior nasal concha is a separate bone largest of the three Frontal sinus Inferior Anterior nasal spine Maxilla Incisive foramen Lacrimal bone Nasal bone Nasal cartilages Superior Middle Sphenoid sinus Palatine bone Sphenoid bone Crista galli Sella turcica Cribriform plate Cribriform foramina Occipital bone Lip Frontal bone Incisor Nasal conchae: Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.13

28. 8-28 Vomer inferior half of the nasal septum –superior half formed by perpendicular plate of ethmoid supports cartilage that forms the anterior part of the nasal septum Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Coronal suture Frontal bone Sphenoid sinus Frontal sinus Crista galli Parietal bone Temporal bone Internal acoustic meatus Jugular foramen Hypoglossal canal Mandibular foramen Styloid process Squamous suture Lambdoid suture Sella turcica Occipital bone Vomer Palatine bone Maxilla Mandible Mental spines Nasal bone (b) Median section Cribriform plate of ethmoid bone Perpendicular plate of ethmoid bone Palatine process of maxilla Figure 8.4b

29. 8-29 strongest bone of the skull only bone of skull that moves noticeably supports lower teeth provides attachments for muscles of facial expression and mastication mental symphysis – median cartilaginous joint in fetus –develops as two separate bones in fetus –ossifies in early childhood mental protuberance – point of chin two major parts on each side –body – supports teeth –ramus – articulates with cranium angle – where body and ramus meet alveolar processes between teeth mental foramen mental spines Mandible Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Zygomatic bone Lambdoid suture Foramen magnum Mastoid foramen Jugular foramen Stylomastoid foramen Carotid canal Intermaxillary suture Palatine bone Greater palatine foramen Medial pterygoid plate Lateral pterygoid plate Foramen ovale Foramen spinosum Foramen lacerum Incisive foramen Sphenoid bone Zygomatic arch Mandibular fossa Styloid process External acoustic meatus Mastoid process Mastoid notch Condylar canal Temporal bone Superior nuchal line Inferior nuchal line Occipital bone (a) Inferior view Parietal bone Occipital condyle Vomer Posterior nasal aperture Palatine process of maxilla Basilar part of occipital bone External occipital protuberance Mandibular condyles Condylar process Mandibular notch Coronoid process Mandibular foramen Body Angle Ramus Mental protuberance Mental foramen Alveolar process Figure 8.5a Figure 8.15 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

30. Ramus, Angle and Body of Mandible condylar process bears the mandibular condyle – oval knob that articulates with the mandibular fossa of the temporal bone forming the hinge temporomandibular joint (TMJ) coronoid process – point of insertion of temporalis muscle mandibular notch mandibular foramen 8-30 Figure 8.15 Mandibular condyles Condylar process Mandibular notch Coronoid process Mandibular foramen Body Angle Ramus Mental protuberance Mental foramen Alveolar process Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

31. 8-31 auditory ossicles –three in each middle-ear cavity –malleus, incus, and stapes hyoid bone –slender u-shaped bone between the chin and larynx –does not articulate with any other bone –suspended from styloid process of skull by muscle and ligament –body and greater and lesser horns (cornua) –fractured hyoid bone is evidence of strangulation Bones Associated With Skull Figure 8.16 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Hyoid Larynx Styloid process Stylohyoid muscle Greater horn Lesser horn Body

32. 8-32 Skull in Infancy and Childhood fontanels - spaces between unfused bones –filled with fibrous membrane –allow shifting of bones during birth and growth of brain –anterior, posterior, sphenoid (anterolateral), and mastoid (posterolateral fontanels two frontal bones fuse by age 6 (metopic suture) skull reaches adult size by 8 or 9 years of age Figure 8.17 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Parietal bone Occipital bone Maxilla Frontal bone Anterior fontanel Sagittal suture Posterior fontanel Mandible (b) Superior view (a) Lateral view Lambdoid suture Squamous suture Mastoid fontanel Temporal bone Parietal bone Sphenoid bone Coronal suture Frontal bone Sphenoid fontanel Nasal bone Zygomatic bone

33. 8-33 The Vertebral Column (Spine) functions –supports the skull and trunk –allows for their movement –protects the spinal cord –absorbs stress of walking, running, and lifting –provides attachments for limbs thoracic cage, and postural muscles 33 vertebrae with intervertebral discs of fibrocartilage between most of them adult vertebral column averages 71 cm. (28 in.) long –intervertebral discs account for about one-quarter of its length –person is 1% shorter when they go to bed –compression squeezes water out during the day and absorbs water when compression removed during sleep Figure 8.18 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cervical vertebrae Thoracic vertebrae Atlas (C1) Axis (C2) C7 Lumbar vertebrae Sacrum Coccyx Anterior viewPosterior view T1 T12 L1 L5 S1 S5

34. 8-34 The Vertebral Column (Spine) five vertebral groups –7 cervical in the neck –12 thoracic in the chest –5 lumbar in lower back –5 fused sacral at base of spine –4 fused coccygeal variations in number of lumbar and sacral vertebrae occur in 1 in 20 people Figure 8.18 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cervical vertebrae Thoracic vertebrae Atlas (C1) Axis (C2) C7 Lumbar vertebrae Sacrum Coccyx Anterior viewPosterior view T1 T12 L1 L5 S1 S5

35. 8-35 Newborn Spinal Curvature spine exhibits one continuous C-shaped curve at birth known as primary curvature Figure 8.20 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. © The McGraw-Hill Companies, Inc./Bob Coyle, photographer

36. 8-36 Adult Spinal Curvatures s-shaped vertebral column with four normal curvatures –cervical –thoracic –lumbar –pelvic primary curvatures – present at birth –thoracic and pelvic secondary curvatures – develop later –cervical and lumbar –lifting head as it begins to crawl develops cervical curvature –walking upright develops lumbar curvature Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Cervical curvature Thoracic curvature Lumbar curvature Pelvic curvature C7 T1 T12 L1 S1 L5 C1 Figure 8.19

37. 8-37 Abnormal Spinal Curvatures from disease, paralysis of trunk muscles, poor posture, pregnancy, or congenital defect scoliosis – abnormal lateral curvature –most common –usually in thoracic region –particularly of adolescent girls –developmental abnormality in which the body and arch fail to develop on one side of the vertebrae kyphosis (hunchback) – exaggerated thoracic curvature –usually from osteoporosis, also osteomalacia or spinal tuberculosis, or wrestling or weightlifting in young boys lordosis (swayback) – exaggerated lumbar curvature – is from pregnancy or obesity Key Normal Pathological (b) Kyphosis (“hunchback”) (c) Lordosis (“hunchback”) (a) Scoliosis Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.21

38. 8-38 General Structure of Vertebra body (centrum) –mass of spongy bone that contains red bone marrow –covered with thin shell of compact bone –weight bearing portion –rough superior and inferior surfaces provide firm attachment for intervertebral discs vertebral foramina –collectively form vertebral canal for spinal cord vertebral arch –composed of two parts on each side –pedicle – pillarlike and lamina - platelike spinous process –projection extending from the apex of arch –extends posteriorly and downward transverse process –extends laterally from point where pedicel and lamina meet superior articular processes –project upward from one vertebra and meets inferior articular processes from the vertebra above facets –flat articular surfaces covered with hyaline cartilage Figure 8.22 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Spinous process Lamina Pedicle Body (a) 2nd lumbar vertebra (L2) Anterior Posterior Superior articular facet Transverse process Vertebral foramen Vertebral arch Nucleus pulposus Anulus fibrosus (b) Intervertebral disc

39. 8-39 Intervertebral Foramen and Discs intervertebral foramen –when two vertebrae are joined they exhibit and opening between their pedicles –passageway for spinal nerves –inferior vertebral notch in the pedicle of the upper vertebra –superior vertebral notch in the pedicle of the lower vertebra intervertebral discs (23) –first one between C2 and C3 –last one between L5 and sacrum –pad consisting of: nucleus pulposus - inner gelatinous mass anulus fibrosus – outer ring of fibrocartilage –bind vertebrae together –support weight of the body –absorb shock –herniated disc (‘ruptured’ or ‘slipped’ disc) puts painful pressure on spinal nerve or spinal cord Figure 8.23b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. L1 L2 L3 Intervertebral disc Spinous process (b) Left lateral view Superior articular process of L1 Inferior vertebral notch of L1 Superior vertebral notch of L2 Inferior articular process of L3 Intervertebral foramen

40. 8-40 Cervical Vertebra C1 - Atlas atlas (C1) –supports the head –has no body –a delicate ring surrounding a large vertebral foramen –lateral masses with superior articular facets articulates with occipital condyles allows nodding motion of skull gesturing ‘yes’ –inferior articular facets articulate with C2 –anterior and posterior arches –anterior and posterior tubercles Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. L2 L3 Body (centrum) Intervertebral disc Lamina (a) Posterior (dorsal) view Transverse process Inferior articular process of L2 Superior articular process of L3 Figure 8.23a

41. 8-41 Cervical Vertebra C2 - Axis axis (C2) –allows rotation of the head gesturing ‘no’ –dens or odontoid process – prominent knob on its anterosuperior side forms as an independent ossification center during first year of life fuses with axis by age 3 to 6 years projects into vertebral foramen of the atlas held in place by a transverse ligament –atlanto-occipital joint – joint between atlas and cranium –atlantoaxial joint – joint between the atlas and axis Figure 8.24b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Inferior articular process Spinous process Lamina Dens (odontoid process) Superior articular facet Body Pedicle Transverse foramen Transverse process (b) Axis

42. 8-42 Atlas and Axis Articulation Figure 8.24c Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Dens Axis of rotation Atlas Axis Transverse ligament (c) Atlantoaxial joint

43. 8-43 Typical Cervical Vertebrae C1-C7 are the smallest and lightest vertebrae, other than the coccygeals bifid or forked spinous process in C2 to C6 small body and larger vertebral foramen transverse foramen in each short transverse process –provides passage and protection for: vertebral arteries – supply blood to the brain vertebral veins – drain blood from various neck structures –transverse foramen only found in cervical vertebrae C7 vertebra prominens – spinous process not bifid and especially long –prominent bump on the lower back of the neck –convenient landmark for counting vertebrae Figure 8.25a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Body Spinous process Lamina Spinous process Inferior articular process Superior articular facet (a) Cervical vertebrae Superior viewsLateral views Transverse foramen Transverse process

44. 8-44 Typical Thoracic Vertebrae Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Transverse process Superior costal facet Inferior costal facet Body Spinous process Inferior articular facet Transverse costal facet Spinous process Lamina Superior articular facet (b) Thoracic vertebrae Transverse costal facet Figure 8.25b 12 thoracic vertebrae (T1 – T12) –corresponds to the 12 pairs of ribs attached to them spinous processes pointed and angled sharply downward larger body than cervical but, smaller than lumbar costal facets for attachment of ribs –on body as small, smooth, slightly concave spots transverse costal facets at end of each transverse process on T1 – T10 –provide second point of articulation for ribs 1 to 10 inferior and superior costal facets on vertebral body – - in most cases, ribs insert between the two vertebra

45. 8-45 Lumbar Vertebrae 5 lumbar vertebrae (L1 – L5) thick, stout body blunt, squarish spinous process superior articular processes face medially –lumbar region resistant to twisting movements Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pedicle Body Spinous process Inferior articular facet Spinous process Superior articular facet Superior articular process (c) Lumbar vertebrae Transverse process Figure 8.25c

46. 8-46 Sacrum (Anterior View) sacrum – bony plate that forms the posterior wall of the pelvic cavity once considered the seat of the soul in children, five separate sacral vertebrae (S1 – S5) begin fusion around age 16 and complete fusion by age 26 anterior surface –smooth and concave –4 transverse lines indicate line of fusion of vertebrae –4 pair of large anterior sacral (pelvic) foramina allow for passage of nerves and arteries into the pelvic organs sacral promontory on S1 supports L5 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Transverse lines Coccyx Ala S1 S2 S3 S4 S5 Co1 Co2 Co3 Co4 (a) Anterior view Superior articular process Sacral promontory Anterior sacral foramina Figure 8.26a

47. 8-47 Sacrum (Posterior View) posterior surface very rough median sacral crest –formed from fusion of spinous processes lateral sacral crest –less prominent, and on either side of median sacral crest –formed from the fusion of the transverse processes posterior sacral foramina –4 pairs of openings for spinal nerves that supply gluteal region and lower limbs sacral canal runs through sacrum and ends as sacral hiatus –contains spinal nerve roots auricular surface is part of sacroiliac (SI) joint formed with hip bone superior articular processes on S1 –articulates with L5 alae – pair of large, rough, winglike extensions lateral to the superior articular processes Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Horn Sacral hiatus Coccyx Sacral canal (b) Posterior view Superior articular process Transverse process Posterior sacral foramina Lateral sacral crest Auricular surface Median sacral crest Figure 8.26b

48. 8-48 Coccyx coccyx – usually consists of four small vertebrae (Co1 – Co4) –sometimes five fuse into a single, triangular bone by age 20 – 30 horns (cornua) on Co1 –serves as attachment points for ligaments that bind the coccyx to the sacrum fractured during difficult childbirth or by hard fall on buttocks provide attachment for muscles of the pelvic floor Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Horn Sacral hiatus Coccyx Sacral canal (b) Posterior view Superior articular process Transverse process Posterior sacral foramina Lateral sacral crest Auricular surface Median sacral crest Figure 8.26b

49. 8-49 Thoracic Cage consists of thoracic vertebrae, sternum and ribs forms conical enclosure for lungs and heart provides attachment for pectoral girdle and upper limbs broad base and narrower apex rhythmically expanded by respiratory muscles to draw air into the lungs costal margin – inferior border of thoracic cage formed by the downward arc of ribs protect thoracic organs, but also the spleen, most of the liver, and to some extent the kidneys Figure 8.27 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sternoclavicular joint Acromioclavicular joint Clavicle Scapula Suprasternal notch Clavicular notch Manubrium Angle Body Xiphoid process Costal cartilages Costal margin True ribs (1–7) 1 2 3 4 5 6 7 8 9 10 11 12 T12 T1 L1 False ribs (8–12) Sternum: Pectoral girdle: Floating ribs (11–12)

50. 8-50 Sternum sternum (breastbone) – bony plate anterior to the heart divided into three regions: –manubrium broad superior portion suprasternal (jugular) notch medially clavicular notches – articulate with clavicle ribs attach along scalloped lateral margins –body (gladiolus) longest part of sternum sternal angle – point where body joins manubrium ribs attach along scalloped lateral margins –xiphoid inferior end of sternum attachment for some of abdominal muscles in cardiopulmonary resuscitation, improperly performed chest compressions can drive xiphoid process into the liver and cause a fatal hemorrhage

51. 8-51 Ribs 12 pairs of ribs –no difference between sexes –posterior (proximal) end attached to vertebral column –anterior (distal) ends mostly attached to the sternum –costal cartilages composed of hyaline cartilage attach anterior ends to sternum head – portion of the rib that articulates with the thoracic vertebrae –superior articular facet –inferior articular facet neck – narrow portion distal to the head tubercle – wider rough area distal to the neck –articulates with transverse costal facet of vertebra angle – lateral curve of rib shaft – long, gentle sloping, bladelike portion of rib –costal groove on inferior margin of shaft Figure 8.28b Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Head Neck Tubercle Rib 6 T6 (b) Superior view Superior articular facet Superior costal facet for rib 6 Transverse costal facet for rib 6 Figure 8.29b Neck Shaft Head Superior Costal groove Inferior Tubercle Angle (b) Ribs 2–10 Articular facet for transverse process Articular facets for vertebral bodies Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

52. 8-52 Articulation of Rib 6 with Vertebrae T5 and T6 Figure 8.29 Head Neck Tubercle Rib 6 T6 (b) Superior view Rib 6 Inferior costal facet of T5 Superior articular facet of rib 6 Inferior articular facet of rib 6 Superior costal facet of T6 (a) Anterior view Vertebral body T5 Vertebral body T6 Transverse costal facet for rib 6 Superior articular facet Superior costal facet for rib 6 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

53. 8-53 True and False Ribs true ribs (ribs 1 to 7) – each has its own costal cartilage connecting it to the sternum false ribs (ribs 8-12) –lack independent cartilaginous connection to the sternum –floating ribs (ribs 11 – 12) articulate with bodies of vertebrae T11 and T12 do not have tubercles do not attach to transverse processes of the vertebra no cartilaginous connection to the sternum or any of the higher costal cartilages Figure 8.27 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Sternoclavicular joint Acromioclavicular joint Clavicle Scapula Suprasternal notch Clavicular notch Manubrium Angle Body Xiphoid process Costal cartilages Costal margin True ribs (1–7) 1 2 3 4 5 6 7 8 9 10 11 12 T12 T1 L1 False ribs (8–12) Sternum: Pectoral girdle: Floating ribs (11–12)

54. 8-54 Pectoral Girdle pectoral girdle (shoulder girdle) – supports the arm consists of two bones on each side of the body –clavicle (collarbone) and scapula (shoulder blade) clavicle articulates medially to the sternum and laterally to the scapula –sternoclavicular joint –acromioclavicular joint scapula articulates with the humerus –glenohumeral joint - shoulder joint –easily dislocated due to loose attachment

55. 8-55 Clavicle clavicle - S-shaped, somewhat flattened bone inferior – grooves and ridges for muscle attachment sternal end - rounded head acromial end – flattened –conoid tubercle – roughened tuberosity near acromial end –ligament attachment braces the shoulder keeping upper limb away from the midline of the body most frequently fractured bone in the body Figure 8.30 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Conoid tubercle (a) Superior view (b) Inferior view Sternal end Acromial end Acromial end Sternal end

56. 8-56 Scapula scapula – named for its resemblance to a spade or shovel triangular plate that posteriorly overlies ribs 2 to 7 –three sides - superior, medial (vertebral) and lateral (axillary) borders –three angles – superior, inferior, and lateral angles suprascapular notch – conspicuous notch on superior border –provides passage for a nerve spine – transverse ridge on posterior surface –supraspinous fossa – indentation superior to the spine –infraspinous fossa – broad surface inferior to the spine subscapular fossa – concave, anterior surface of scapula complex lateral angle of scapula has three main features: –acromion – platelike extension of the spine forms apex of the shoulder articulates with the clavicle – the sole point of attachment of the scapula and the upper limb to the rest of the skeleton –coracoid process – shaped like a bent finger provides attachment for tendons of the biceps brachii and other arm muscles –glenoid cavity – shallow socket that articulates with the head of the humerus forming glenohumeral joint

57. 8-57 Scapula Figure 8.31 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Superior angle Acromion Spine Acromion Inferior angle (a) Anterior view(b) Posterior view Suprascapular notch Coracoid process Glenoid cavity Subscapular fossa Lateral border Medial border Superior border Supraspinous fossa Lateral angle Infraspinous fossa

58. 8-58 Upper Limb upper limb is divided into four regions containing a total of 30 bones per limb –brachium (arm proper) – extends from shoulder to elbow contains only one bone - humerus –antebrachium (forearm) – extends from elbow to wrist contains two bones - radius and ulna –carpus (wrist) contains 8 small bones arranged in 2 rows –manus (hand) 19 bones in 2 groups –5 metacarpals in palm –14 phalanges in fingers

59. 8-59 Humerus proximal end –hemispherical head that articulates with the glenoid cavity of scapula –anatomical neck –greater and lesser tubercles and deltoid tuberosity –intertubercular sulcus holds biceps tendon –surgical neck distal end –rounded capitulum articulates with head of radius –trochlea articulates with ulna –lateral and medial epicondyles –lateral and medial supracondylar ridges –olecranon fossa holds olecranon process of ulna –coronoid fossa –radial fossa Capitulum Head Trochlea (a) Anterior view(b) Posterior view Greater tubercle Lesser tubercle Intertubercular sulcus Deltoid tuberosity Coronoid fossa Radial fossa Lateral epicondyle Surgical neck Greater tubercle Anatomical neck Nutrient foramen Deltoid tuberosity Medial supracondylar ridge Medial epicondyle Lateral supracondylar ridge Lateral epicondyle Olecranon fossa Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.32

60. 8-60 Radius radius –head – disc-shape, allows for rotation around the longitudinal axis of the bone during pronation and supination of hand superior surface articulates with capitulum on humerus side of disc spins on radial notch on ulna –neck –radial tuberosity for biceps muscle –styloid process can be palpated near thumb –ulnar notch Figure 8.33 Olecranon (a) Anterior view(b) Posterior view Articular facets Ulna Radius Ulnar tuberosity Coronoid process Trochlear notch Radial notch of ulna Head of radius Neck of radius Radial tuberosity Styloid process Interosseous borders Interosseous membrane Ulnar notch of radius Head of ulna Styloid process Styloid process Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Head of radius Neck of radius

61. 8-61 Ulna and Interosseous Membrane ulna –trochlear notch articulates with trochlea of humerus –olecranon – bony point at back of elbow –coronoid process –radial notch holds head of radius –styloid process interosseous membrane –ligament attaches radius to ulna along interosseous margin of each bone –enables the two elbow joints to share the load Figure 8.33 Olecranon (a) Anterior view(b) Posterior view Articular facets Ulna Radius Ulnar tuberosity Coronoid process Trochlear notch Radial notch of ulna Head of radius Neck of radius Radial tuberosity Styloid process Interosseous borders Interosseous membrane Ulnar notch of radius Head of ulna Styloid process Styloid process Head of radius Neck of radius Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

62. 8-62 Carpal Bones 8 bones form wrist –allow movements of flexion, extension, abduction and adduction 2 rows (4 bones each) –proximal row – –scaphoid, lunate, triquetrum, and pisiform pisiform is a sesamoid developed by age 9 to12 in tendon of flexor carpi ulnaris muscle –distal row - trapezium, trapezoid, capitate, and hamate Figure 8.34a I IIIII IV V Distal phalanx II Middle phalanx II Proximal phalanx II Head Body Base Hamulus of hamate Hamate Pisiform Triquetrum Lunate Capitate Trapezium Trapezoid Body Head Scaphoid Base Phalanges Key to carpal bones Distal row Proximal row Distal phalanx I Proximal phalanx I First metacarpal Carpal bones Metacarpal bones Carpal bones Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Anterior view

63. 8-63 Metacarpals and Phalanges Figure 8.34a I IIIII IV V Distal phalanx II Middle phalanx II Proximal phalanx II Head Body Base Hamulus of hamate Hamate Pisiform Triquetrum Lunate Capitate Trapezium Trapezoid Body Head Scaphoid Base Phalanges Key to carpal bones Distal row Proximal row Distal phalanx I Proximal phalanx I First metacarpal Carpal bones Metacarpal bones Carpal bones Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Anterior view metacarpals - bones of the palm –metacarpal I proximal to base of thumb –metacarpal V proximal to base of little finger –proximal base, body, and distal head phalanges - bones of the fingers –thumb or pollex has two phalanges proximal and distal phalanx –fingers have three phalanges proximal, middle and distal phalanx

64. Sesamoid Bone pisiform –develops around age 9 – 12 years –in tendon of flexor carpi ulnaris muscle 8-64

65. 8-65 Pelvic Girdle pelvic girdle – consists of a complete ring composed of three bones –two hip (coxal) bones also called ossa coxae or innominate bones –sacrum that is also part of the vertebral column pelvis – bowl-shaped structure composed of the two coxal bones and sacrum as well as their ligaments and muscles that line the pelvic cavity and form its floor –supports trunk on the lower limbs and protects viscera, lower colon, urinary bladder, and internal reproductive organs sacroiliac joint - joins hipbone to the vertebral column –auricular surface of ileum to auricular surface of sacrum anteriorly, interpubic disc – pad of fibrocartilage joins pubic bones pubic symphysis – the interpubic disc and adjacent regions of the pubic bone on each side Figure 8.35a Ilium Ischium Coccyx Body Ramus Pubis (a) Anterosuperior view Pubic symphysis Acetabulum Spine Pelvic inlet Sacroiliac joint Body Superior ramus Inferior ramus Iliac crest Iliac fossa Anterior superior iliac spine Anterior inferior iliac spine Base of sacrum Pelvic surface of sacrum Interpubic disc Obturator foramen Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

66. 8-66 Pelvic Inlet and Outlet greater (false) pelvis – between flare of the hips lesser (true) pelvis – narrower and below pelvic brim – round margin that separates the two pelvic inlet – opening circumscribed by brim that infant’s head must pass during birth pelvic outlet – lower margin of the lesser pelvis Figure 8.35b Figure 8.35a Ilium Ischium Coccyx Body Ramus Pubis (a) Anterosuperior view Pubic symphysis Acetabulum Spine Pelvic inlet Sacroiliac joint Body Superior ramus Inferior ramus Iliac crest Iliac fossa Anterior superior iliac spine Anterior inferior iliac spine Base of sacrum Pelvic surface of sacrum Interpubic disc Obturator foramen Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (b) Median section Pelvic inlet Pelvic brim Greater pelvis Pelvic outlet Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Lesser pelvis

67. 8-67 Hip Bone three distinct features of hip bone –iliac crest – superior crest of hip –acetabulum – the hip socket –obturator foramen – large hole below acetabulum each adult hip bone is formed by the fusion of three childhood bones –ileum the largest extends from the iliac crest to the center of the acetabulum anterior and posterior superior spine anterior and posterior inferior spines greater sciatic notch and iliac fossa –ischium inferioposterior portion of hip heavy body with prominent spine lesser sciatic notch ischial tuberosity ramus –pubis (pubic bone) most anterior portion of the hip bone body, superior and inferior ramus Figure 8.36a Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. IliumIschiumPubis Posterior superior Iliac spine Anterior superior iliac spine Greater sciatic notch Inferior gluteal line Anterior gluteal line Ischial spine Acetabulum Ischial tuberosity (a) Lateral view Body of ischium Lesser sciatic notch Iliac crest Anterior inferior iliac spine r Body of ilium Body of pubis Inferior ramus of pubis Obturator foramen Ramus of ischium Superior ramus of pubis Posterior gluteal line Posterior inferior Iliac spine

68. 8-68 Comparison of Male and Female male - heavier and thicker due to forces exerted by stronger muscles female - wider and shallower, and adapted to the needs of pregnancy and childbirth, larger pelvic inlet and outlet for passage of infant’s head Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Male Female 90  120  Pubic arch Obturator foramen Pelvic inlet Pelvic brim Figure 8.37

69. 8-69 Lower Limb lower limb divided into four regions containing 30 bones per limb –femoral region (thigh) – extends from hip to knee region contains the femur and patella –crural region (leg proper) – extends from knee to ankle contains medial tibia and lateral fibula –tarsal region (tarsus) – ankle – the union of the crural region with the foot tarsal bones are considered part of the foot –pedal region (pes) - foot composed of 7 tarsal bones, 5 metatarsals, and 14 phalanges in the toes

70. 8-70 Femur longest and strongest bone of the body hemispherical head that articulates with the acetabulum of the pelvis –forms ball-and-socket joint –fovea capitis – pit in head of femur for attachment of a ligament constricted neck greater and lesser trochanters for muscle attachment intertrochanteric crest – thick oblique ridge on the posterior surface that connects the trochanters intertrochanteric line – more delicate ridge on the anterior surface that connects trochanters linea aspera – ridge on posterior of the shaft spiral (pectineal) line and gluteal tuberosity medial and lateral condyles and epicondyles found distally intercondylar fossa patellar and popliteal surface Figure 8.38 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Greater trochanter Intertrochanteric line Lateral epicondyle Patellar surface (b) Posterior view Lateral epicondyle Medial supracondylar line Lateral condyle Linea aspera Intertrochanteric crest Gluteal tuberosity Greater trochanter Head Fovea capitis Neck Lesser trochanter Spiral line Shaft Medial epicondyle Popliteal surface Medial condyle Intercondylar fossa Base of patella Articular facets Apex of patella Lateral supracondylar line (a) Anterior view

71. 8-71 Patella (Kneecap) patella - triangular sesamoid bone embedded in tendon of the knee cartilaginous at birth –ossifies at 3 to 6 year base – broad, superior portion apex – pointed, inferior portion articular facets – shallow, posterior portion quadriceps femoris tendon extends from the anterior muscle of the thigh to the patella –continues as the patellar ligament from the patella to the tibia Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Greater trochanter Intertrochanteric line Lateral epicondyle Patellar surface (b) Posterior view Lateral epicondyle Medial supracondylar line Lateral condyle Linea aspera Intertrochanteric crest Gluteal tuberosity Greater trochanter Head Fovea capitis Neck Lesser trochanter Spiral line Shaft Medial epicondyle Popliteal surface Medial condyle Intercondylar fossa Base of patella Articular facets Apex of patella Lateral supracondylar line (a) Anterior view Figure 8.38

72. 8-72 Tibia tibia - thick, medial, weight- bearing bone –only weight bearing bone of the crural region –broad superior head –medial and lateral condyles fairly flat articular surfaces articulate with condyle of femur –intercondylar eminence – ridge separating condyles –tibial tuberosity – attachment of quadricep muscles –anterior crest – sharp, angular –medial malleolus – bony knob on inside of ankle Lateral condyle Apex Head of fibula Intercondylar eminence Lateral surface Distal tibiofibular joint Lateral malleolus Fibula Anterior crest Lateral malleolus (b) Posterior view Proximal tibiofibular joint Tibia Medial malleolus Medial condyle Tibial tuberosity Interosseous membrane (a) Anterior view Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.39

73. 8-73 Fibula fibula – slender, lateral strut that helps stabilizes ankle does not bear any body weight –spare bone tissue for grafts head - proximal end apex – point of the head lateral malleolus - distal expansion, bony knob on lateral side of ankle joined to tibia by interosseous membrane Lateral condyle Apex Head of fibula Intercondylar eminence Lateral surface Distal tibiofibular joint Lateral malleolus Fibula Anterior crest Lateral malleolus (b) Posterior view Proximal tibiofibular joint Tibia Medial malleolus Medial condyle Tibial tuberosity Interosseous membrane (a) Anterior view Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.39

74. 8-74 The Ankle and Foot tarsal bones – arranged in proximal and distal groups tarsal bones are shaped and arranged differently from carpal bones due to load-bearing role of the ankle calcaneus – largest tarsal bone –forms heel –distal portion is point of attachment for calcaneal (Achilles) tendon talus is most superior tarsal bone –forms ankle joint with tibia and fibula –sits upon calcaneus and articulates with navicular proximal row of tarsal bones –talus, calcaneus, and navicular distal row of tarsal bones –medial, intermediate and lateral cuneiforms and cuboid Key to tarsal bones Distal group Proximal group Distal phalanx I Proximal phalanx I Metatarsal Medial cuneiform Intermediate cuneiform Lateral cuneiform Navicular Talus (a) Superior (dorsal) view Calcaneus Cuboid V IV III II I Trochlear surface of talus Tuberosity of calcaneus Proximal phalanx V Middle phalanx V Distal phalanx V Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.40a

75. 8-75 The Foot remaining bones of foot are similar in name and arrangement to the hand metatarsals –metatarsal I is proximal to the great toe (hallux) –metatarsal V is proximal to the little toe –proximal base, intermediate shaft, and distal head phalanges –2 in great toe proximal and distal phalanx –3 in all other toes proximal, middle and distal phalanx Key to tarsal bones Distal group Proximal group Distal phalanx I Proximal phalanx I Metatarsal Medial cuneiform Intermediate cuneiform Lateral cuneiform Navicular Talus (a) Superior (dorsal) view Calcaneus Cuboid V IV III II I Trochlear surface of talus Tuberosity of calcaneus Proximal phalanx V Middle phalanx V Distal phalanx V Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 8.40a

76. 8-76 Embryonic Limb Rotation rotation of upper and lower limbs in opposite directions –starts seventh week of embryonic development –largest digit medial in foot and lateral in hand –each limb rotates about 90° in opposite directions –rotation also explains why elbow flexes posteriorly and knee flexes anteriorly Figure 8.41 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Seven weeks(b) Eight weeks Thumb Elbow Knee Great toe Future thumb Future great toe

77. 8-77 Foot Arches –sole of foot is not flat on ground –3 springy arches absorb stress medial longitudinal arch – from heel to hallux –formed from the calcaneus, talus, navicular, cuneiforms and metatarsals I and III lateral longitudinal arch –from heel to little toe –includes calcaneus, cuboid,and metatarsals IV and V transverse arch –across middle of foot –includes the cuboid, cuneiforms, and proximal heads of metatarsals –arches held together by short, strong ligaments pes planus (flat feet) – excessive weight, repetitious stress, or congenital weakness Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Inferior (plantar) view Medial longitudinal arch Transverse arch Lateral longitudinal arch Figure 8.42a

78. 8-78 Skeletal Adaptations for Bipedalism humans are only animals habitually bipedal –3.6 million year old human footprints indicate upright walking adaptations –strong, springy foot arches –great toe not opposable –femurs angle inward so knees are closer together – erect posture requires less muscular effort –viscera supported in bowl-shaped pelvis –insertions of gluteal muscles differ from other primates

79. 8-79 Bipedalism and Limb Adaptations Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. (a) Foot Human Chimpanzee Figure 8.43(1)a,b (b) Knee ChimpanzeeHuman Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

80. 8-80 Bipedalism and Upright Stance (c) Gluteal muscles Chimpanzee Human Chimpanzee (d) Pelvis Chimpanzee Human (e) Vertebral column Figure 8.43(2)d,eFigure 8.43(1)c Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

81. 8-81 Bipedalism and Head Position Figure 8.43(2)f Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Pivot Chimpanzee Human (f) Skull Supraorbital ridge Foramen magnum Foramen magnum