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Chapter 7 The Skeletal System: The Axial Skeleton Lecture Outline Principles of Human Anatomy and Physiology, 11e 1 INTRODUCTION • Familiarity with the names, shapes, and positions of individual bones helps to locate other organs and to understand how muscles produce different movements due to attachment on individual bones and the use of leverage with joints. • The bones, muscles, and joints together form the musculoskeletal system. Principles of Human Anatomy and Physiology, 11e 2 Chapter 7 The Skeletal System:The Axial Skeleton • Axial Skeleton – 80 bones – lie along longitudinal axis – skull, hyoid, vertebrae, ribs, sternum, ear ossicles • Appendicular Skeleton – 126 bones – upper & lower limbs and pelvic & pectoral girdles Principles of Human Anatomy and Physiology, 11e 3 DIVISIONS OF THE SKELETAL SYSTEM • The axial skeleton consists of bones arranged along the longitudinal axis of the body. The parts of the axial skeleton, composed of 80 bones, are the skull, hyoid bone, vertebral column, sternum, and ribs (Figure 7.1). • The appendicular skeleton comprises one of the two major divisions of the skeletal system.It consists of 126 bones in the upper and lower extremities (limbs or appendages) and the pectoral (shoulder) and pelvic (hip) girdles, which attach them to the rest of the skeleton. Principles of Human Anatomy and Physiology, 11e 4 Types of Bones • 5 basic types of bones: – long = compact – short = spongy except surface – flat = plates of compact enclosing spongy – irregular = variable – sesamoid = develop in tendons or ligaments (patella) • Sutural bones = in joint between skull bones Principles of Human Anatomy and Physiology, 11e 5 BONE SURFACE MARKINGS • There are two major types of surface markings. – Depressions and openings participate in joints or allow the passage of soft tissue. – Processes are projections or outgrowths that either help form joints or serve as attachment points for connective tissue. • Table 7.2 describe the various surface markings along with examples of each. Principles of Human Anatomy and Physiology, 11e 6 Bone Surface Markings from Table 7.2 • • • • • • • • • Foramen = opening Fossa = shallow depression Sulcus = groove Meatus = tubelike passageway or canal Condyle = large, round protuberance Facet = smooth flat articular surface Trochanter = very large projection Tuberosity = large, rounded, roughened projection Learning the terms found in this Table will simplify your study of the skeleton. Principles of Human Anatomy and Physiology, 11e 7 SKULL • The skull, composed of 22 bones, consists of the cranial bones (cranium) and the facial bones (face) (Figures. 7.3 through 7.8). • General Features – The skull forms the large cranial cavity and smaller cavities, including the nasal cavity and orbits (eye sockets). – Certain skull bones contain mucous membrane lined cavities called paranasal sinuses. – The only moveable bone of the skull, other than the ear ossicles within the temporal bones, is the mandible. – Immovable joints called sutures hold the skull bones together. Principles of Human Anatomy and Physiology, 11e 8 The Skull • 8 Cranial bones – protect brain & house ear ossicles – muscle attachment for jaw, neck & facial muscles • 14 Facial bones – protect delicate sense organs -- smell, taste, vision – support entrances to digestive and respiratory systems Principles of Human Anatomy and Physiology, 11e 9 The 8 Cranial Bones Frontal Parietal (2) Temporal (2) Occipital Principles of Human Anatomy and Physiology, 11e Sphenoid Ethmoid 10 Frontal Bone • • • • Forehead, roof of orbits, & anterior cranial floor Frontal suture gone by age 6 (metopic suture) Supraorbital margin and frontal sinus A “black eye” results from accumulation of fluid and blood in the upper eyelid following a blow to the relatively sharp supraorbital margin (brow line). Principles of Human Anatomy and Physiology, 11e 11 cranial bone functions • They protect the brain. – Their inner surfaces attach to membranes that stabilize the positions of the brain, blood vessels, and nerves. – The outer surfaces of cranial bones provide large areas of attachment for muscles that move the various parts of the head. – Facial bones form the framework of the face and protect and provide support for the nerves and blood vessels in that area. • Cranial and facial bones together protect and support the special sense organs. Principles of Human Anatomy and Physiology, 11e 12 Parietal & Temporal Bones • Parietal – sides & roof of cranial cavity • Temporal – temporal squama – zygomatic process forms part of arch – external auditory meatus – mastoid process – styloid process – stylomastoid foramen(VII) – mandibular fossa (TMJ) – petrous portion (VIII) Principles of Human Anatomy and Physiology, 11e 13 Temporal and Occipital bones • Temporal – carotid foramen (carotid artery) – jugular foramen (jugular vein) • Occipital – foramen magnum – occipital condyles – external occipital protuberance attachment for ligamentum nuchae – superior & inferior nuchal lines Principles of Human Anatomy and Physiology, 11e 14 Sphenoid bone • Base of skull • Pterygoid processes are attachment sites for jaw muscles Principles of Human Anatomy and Physiology, 11e 15 Sphenoid in Anterior View • Body is a cubelike portion holding sphenoid sinuses • Greater and lesser wings • Pterygoid processes Principles of Human Anatomy and Physiology, 11e 16 Sphenoid from Superior View • Lesser wing & greater wing • Sella turcica holds pituitary gland • Optic foramen Principles of Human Anatomy and Physiology, 11e 17 Ethmoid Bone • The ethmoid bone forms part of the anterior portion of the cranial floor, the medial wall of the orbits, the superior portion of the nasal septum, and most of the superior side walls of the nasal cavity. It is a major superior supporting structure of the nasal cavity (Figures 7.11, 7.13). • Crista galli attaches to the membranes that cover the brain Principles of Human Anatomy and Physiology, 11e 18 Ethmoid bone • Lateral masses contain ethmoid sinuses • Perpendicular plate is upper part of nasal septum • Superior & middle nasal concha or turbinates – filters & warms air Principles of Human Anatomy and Physiology, 11e 19 14 Facial Bones Nasal (2) Mandible (1) Inferior nasal conchae (2) Principles of Human Anatomy and Physiology, 11e Maxillae (2) Lacrimal (2) Zygomatic (2) Palatine (2) Vomer (1) 20 Maxillary bones • • • • Floor of orbit, floor of nasal cavity or hard palate Maxillary sinus Alveolar processes hold upper teeth Cleft palate is lack of union of maxillary bones Principles of Human Anatomy and Physiology, 11e 21 Zygomatic Bones • Cheekbones • Lateral wall of orbit along with sphenoid • Part of zygomatic arch along with part of temporal Principles of Human Anatomy and Physiology, 11e 22 Lacrimal and Inferior Nasal Conchae • Lacrimal bones – part of medial wall of orbit Inferior Nasal Conchae – lacrimal fossa houses lacrimal sac • Inferior nasal concha or turbinate (not part of ethmoid) Principles of Human Anatomy and Physiology, 11e 23 Mandible • • • • Body, angle & rami Condylar & coronoid processes Alveolar processes for lower teeth Mandibular & mental foramen Principles of Human Anatomy and Physiology, 11e 24 TMJ • The mandible articulates with the temporal bone to form the temporomandibular joint (Figure 7.4). • Temporomandibular joint (TMJ) syndrome is dysfunction to varying degrees of the temporomandibular joint. Causes appear to be numerous and the treatment is similarly variable. Principles of Human Anatomy and Physiology, 11e 25 Palatine & Vomer • Palatine – L-shaped : one end is back part of hard palate, other end is part of orbit (see previous picture) • Vomer – posterior part of nasal septum Principles of Human Anatomy and Physiology, 11e 26 Nasal Septum • The nasal septum is a vertical partition that divides the nasal cavity into right and left sides (Figure 7.11). • A deviated nasal septum is a lateral deflection of the septum from the midline, usually resulting from improper fusion of septal bones and cartilage. Principles of Human Anatomy and Physiology, 11e 27 Nasal Septum • Divides nasal cavity into left and right sides • Formed by vomer, perpendicular plate of ethmoid and septal cartilage • Deviated septum does not line in the midline – developmental abnormality or trauma Principles of Human Anatomy and Physiology, 11e 28 The orbits (eye sockets) • The orbits contain the eyeballs and associated structures and are formed by seven bones of the skull (Figure 7.12). • Five important foramina are associated with each orbit Principles of Human Anatomy and Physiology, 11e 29 Bones of the Orbit – – – – – Roof is frontal and sphenoid Lateral wall is zygomatic and sphenoid Floor is maxilla, zygomatic and sphenoid Medial wall is maxilla, lacrimal, ethmoid and sphenoid Orbital fissures and optic foramen Principles of Human Anatomy and Physiology, 11e 30 Foramina of the Skull • Table 7.4 describes major openings of skull • In which bone would you find the following and what is their function? – foramen magnum – optic foramen – mandibular foramen – carotid canal – stylomastoid foramen Principles of Human Anatomy and Physiology, 11e 31 Unique Features of the Skull Principles of Human Anatomy and Physiology, 11e 32 Sutures • Sutures are immovable joints found only between skull bones and hold skull bones together. • Sutures include the coronal, sagittal, lamboidal,and squamous sutures, among others (Figures 7.4, 7.6). Principles of Human Anatomy and Physiology, 11e 33 Sutures • Lamboid suture unites parietal and occipital • Sagittal suture unites 2 parietal bones Principles of Human Anatomy and Physiology, 11e 34 Sutures • Coronal suture unites frontal and both parietal bones • Squamous suture unites parietal and temporal bones Principles of Human Anatomy and Physiology, 11e 35 Paranasal Sinuses • Paranasal sinuses are cavities in bones of the skull that communicate with the nasal cavity. – They are lined by mucous membranes and also serve to lighten the skull and serve as resonating chambers for speech. – Cranial bones containing the sinuses are the frontal, sphenoid, ethmoid, and maxillae. – Sinusitis occurs when membranes of the paranasal sinuses become inflamed due to infection or allergy. Principles of Human Anatomy and Physiology, 11e 36 Paranasal Sinuses • • • • Paired cavities in ethmoid, sphenoid, frontal and maxillary Lined with mucous membranes and open into nasal cavity Resonating chambers for voice, lighten the skull Sinusitis is inflammation of the membrane (allergy) Principles of Human Anatomy and Physiology, 11e 37 Paranasal Sinuses • • • • Paired cavities in ethmoid, sphenoid, frontal and maxillary Lined with mucous membranes and open into nasal cavity Resonating chambers for voice, lighten the skull Sinusitis is inflammation of the membrane (allergy) Principles of Human Anatomy and Physiology, 11e 38 Fontanels • Fontanels are dense connective tissue membrane-filled spaces between the cranial bones of fetuses and infants. They remain unossified at birth but close early in a child’s life (Figure 7.14). – The major fontanels are the anterior, posterior, anterolaterals, and posterolaterals . • Fontanels have two major functions. – They enable the fetal skull to modify its size and shape as it passes through the birth canal. – They permit rapid growth of the brain during infancy. Principles of Human Anatomy and Physiology, 11e 39 Fontanels of the Skull at Birth. • Dense connective tissue membrane-filled spaces (soft spots) • Unossified at birth but close early in a child's life. Principles of Human Anatomy and Physiology, 11e 40 HYOID BONE • The hyoid bone is a unique component of the axial skeleton because it does not articulate with any other bones. • The hyoid bone consists of a horizontal body and paired projections, the lesser and greater horns. (Figure 7.15) Principles of Human Anatomy and Physiology, 11e 41 Hyoid Bone – U-shaped single bone – Articulates with no other bone of the body – Suspended by ligament and muscle from skull – Supports the tongue & provides attachment for tongue, neck and pharyngeal muscles Principles of Human Anatomy and Physiology, 11e 42 VERTEBRAL COLUMN • The vertebral column, along with the sternum and ribs, makes up the trunk of the skeleton. • The 26 bones of the vertebral column are arranged into five regions: cervical, thoracic, lumbar, sacral, and coccygeal (Figure 7.16a). Principles of Human Anatomy and Physiology, 11e 43 Vertebral Column • Backbone or spine built of 26 vertebrae • Five vertebral regions – cervical vertebrae (7) in the neck – thoracic vertebrae ( 12 ) in the thorax – lumbar vertebrae ( 5 ) in the low back region – sacrum (5, fused) – coccyx (4, fused) Principles of Human Anatomy and Physiology, 11e 44 Intervertebral Discs • Between adjacent vertebrae absorbs vertical shock • Permit various movements of the vertebral column • Fibrocartilagenous ring with a pulpy center Principles of Human Anatomy and Physiology, 11e 45 Normal Curves of the Vertebral Column • The four normal vertebral curves are the cervical and lumbar (anteriorly convex curves) and thoracic and sacral (anteriorly concave curves) (Figure 7.16b). • Between adjacent vertebrae, from the first cervical (atlas) to the sacrum, are intervertebral discs that form strong joints, permit various movements of the vertebral column, and absorb vertical shock (Figure 7.16d). – In the fetus, there is only a single anteriorly concave curve (Figure 7.16c). – The cervical curve develops as the child begins to hold his head erect. – The lumbar curve develops as the child begins to walk. – All curves are fully developed by age 10. Principles of Human Anatomy and Physiology, 11e 46 Normal Curves of the Vertebral Column • Primary curves – thoracic and sacral are formed during fetal development • Secondary curves – cervical if formed when infant raises head at 4 months – lumbar forms when infant sits up & begins to walk at 1 year Principles of Human Anatomy and Physiology, 11e 47 Vertebrae • Parts of a typical vertebra include a body, a vertebral arch, and several processes (Figure 7.17). Principles of Human Anatomy and Physiology, 11e 48 Typical Vertebrae Principles of Human Anatomy and Physiology, 11e • Body – weight bearing • Vertebral arch – pedicles – laminae • Vertebral foramen • Seven processes – 2 transverse – 1 spinous – 4 articular • Vertebral notches 49 Intervertebral Foramen & Spinal Canal • Spinal canal is all vertebral foramen together • Intervertebral foramen are 2 vertebral notches together Principles of Human Anatomy and Physiology, 11e 50 Regions of the Vertebral Column Principles of Human Anatomy and Physiology, 11e 51 Cervical Region • There are 7 cervical vertebrae (Figure 7.18a). – The first cervical vertebra is the atlas and supports the skull (Figure 7.18a, b). – The second cervical vertebra is the axis, which permits side-to-side rotation of the head (Figure 7.18a, c). – The third to sixth correspond to the structural patterns of the typical cervical vertebrae (Figure 7.18d). – The seventh called the vertebra prominens is somewhat different (Figure 7.18) Principles of Human Anatomy and Physiology, 11e 52 Typical Cervical Vertebrae (C3-C7) • Smaller bodies but larger spinal canal • Transverse processes – shorter, with transverse foramen for vertebral artery • Spinous processes of C2 to C6 often bifid • 1st and 2nd cervical vertebrae are unique - atlas & axis Principles of Human Anatomy and Physiology, 11e 53 Atlas & Axis (C1-C2) • Atlas -- ring of bone, superior facets for occipital condyles – nodding movement at atlanto-occipital joint signifies “yes” • Axis -- dens or odontoid process is body of atlas – pivotal movement at atlanto-axial joint signifies “no” Principles of Human Anatomy and Physiology, 11e 54 Thoracic Region • There are 12 thoracic vertebrae (Figure 7.19). • These vertebrae articulate with the ribs. Principles of Human Anatomy and Physiology, 11e 55 Thoracic Vertebrae (T1-T12) • Larger and stronger bodies • Longer transverse & spinous processes • Facets or demifacets on body for head of rib • Facets on transverse processes (T1-T10) for tubercle of rib Principles of Human Anatomy and Physiology, 11e 56 Lumbar Region • There are 5 lumbar vertebrae (Figure 7.20). • They are the largest and strongest vertebrae in the column. • Table 7.4 summarizes the major structural differences among the cervical, thoracic, and lumbar vertebrae. Principles of Human Anatomy and Physiology, 11e 57 Lumbar Vertebrae • Strongest & largest • Short thick spinous & transverse processes – back musculature Principles of Human Anatomy and Physiology, 11e 58 Sacrum • The sacrum is formed by the union of 5 sacral vertebrae (Figure 7.21a) and serves as a strong foundation for the pelvic girdle. • Table 8.1 shows the differences between the male and female sacrum. Principles of Human Anatomy and Physiology, 11e 59 Sacrum • Union of 5 vertebrae (S1 - S5) by age 30 – median sacral crest was spinous processes – sacral ala is fused transverse processes • Sacral canal ends at sacral hiatus • Auricular surface & sacral tuberosity of SI joint Principles of Human Anatomy and Physiology, 11e 60 Coccyx • The coccyx is formed by the fusion of 4 coccygeal vertebrae (Figure 7.21). • Caudal anesthesia (epidural block), frequently used during labor (in childbirth), causes numbness in the regions innervated by the sacral and coccygeal nerves (approximately from the waist to the knees). Principles of Human Anatomy and Physiology, 11e 61 Coccyx • Union of 4 vertebrae (Co1 - Co4) by age 30 • Caudal or epidural anesthesia during delivery – into sacral hiatus anesthetize sacral & coccygeal nerves – sacral and coccygeal cornu are important landmarks Principles of Human Anatomy and Physiology, 11e 62 THORAX • The term thorax refers to the entire chest. • The skeletal part of the thorax (a bony cage) consists of the sternum, costal cartilages, ribs, and the bodies of the thoracic vertebrae (Figure 7.22). • The thoracic cage encloses and protects the organs in the thoracic and superior abdominal cavities. It also provides support for the bones of the shoulder girdle and upper limbs. Principles of Human Anatomy and Physiology, 11e 63 Thorax Principles of Human Anatomy and Physiology, 11e 64 Thorax – Bony cage flattened from front to back – Sternum (breastbone) – Ribs • 1-7 are true ribs (vertebrosternal) • 8-12 are false ribs (vertebrochondral) • 11-12 are floating – Costal cartilages – Bodies of the thoracic vertebrae. Principles of Human Anatomy and Physiology, 11e 65 Sternum • The sternum is located on the anterior midline of the thoracic wall. • It consists of three parts: manubrium, body, and xiphoid process (Figure 7.22). Principles of Human Anatomy and Physiology, 11e 66 Sternum Principles of Human Anatomy and Physiology, 11e • Manubrium – 1st & 2nd ribs – clavicular notch • Body – costal cartilages of 210 ribs • Xiphoid – ossifies by 40 – CPR position – abdominal mm. • Sternal puncture – biopsy 67 Ribs • The 12 pairs of ribs give structural support to the sides of the thoracic cavity (Figure 7.22b). – The first 7 pairs of ribs are called true ribs; the remaining five pairs, false ribs (with the last two false ribs called floating ribs). – Figure 7.23a shows the parts of a typical rib. – Rib fractures are the most common types of chest injuries. Principles of Human Anatomy and Physiology, 11e 68 Ribs • • • • Increase in length from ribs 1-7, thereafter decreasing Head and tubercle articulate with facets Body with costal groove containing nerve & blood vessels Intercostal spaces contain intercostal muscles Principles of Human Anatomy and Physiology, 11e 69 Rib Articulation • Tubercle articulates with transverse process • Head articulates with vertebral bodies Principles of Human Anatomy and Physiology, 11e 70 DISORDERS: HOMEOSTATIC IMBALANCES • Protrusion of the nucleus pulposus into an adjacent vertebral body is called a herniated (slipped) disc (Figure 7.24). This movement exerts pressure on spinal nerves, causing considerable pain. Principles of Human Anatomy and Physiology, 11e 71 Herniated (Slipped) Disc • Protrusion of the nucleus pulposus • Most commonly in lumbar region • Pressure on spinal nerves causes pain • Surgical removal of disc after laminectomy Principles of Human Anatomy and Physiology, 11e 72 DISORDERS: HOMEOSTATIC IMBALANCES • Abnormal curvatures of the vertebral column include scoliosis, an lateral bending of the vertebral column; kyphosis, an exaggerated curve of the thoracic curve; and lordosis, an exaggeration of the lumbar curve (Figure 7.25 a-c). • Spina bifida is a congenital defect caused by failure of the vertebral laminae to unite at the midline. This may involve only one or several vertebrae; nervous tissue may or may not protrude through the skin (Figure 7.26). Principles of Human Anatomy and Physiology, 11e 73 Clinical Problems • Abnornal curves of the spine. – scoliosis (lateral bending of the column) – kyphosis (exaggerated thoracic curve) – lordosis (exaggerated lumbar curve) • Spina bifida is a congenital defect – failure of the vertebral laminae to unite – nervous tissue is unprotected – paralysis Principles of Human Anatomy and Physiology, 11e 74 end Principles of Human Anatomy and Physiology, 11e 75 Chapter 8 The Skeletal System: Appendicular Skeleton Lecture Outline Principles of Human Anatomy and Physiology, 11e 76 INTRODUCTION • The appendicular skeleton includes the bones of the upper and lower extremities and the shoulder and hip girdles. • The appendicular skeleton functions primarily to facilitate movement. Principles of Human Anatomy and Physiology, 11e 77 Chapter 8 The Skeletal System: Appendicular Skeleton • Pectoral girdle • Pelvic girdle • Upper limbs • Lower limbs Principles of Human Anatomy and Physiology, 11e 78 Pectoral (Shoulder) Girdle The pectoral or shoulder girdle attaches the bones of the upper limbs to the axial skeleton (Figure 8.1). • Consists of scapula and clavicle • Clavicle articulates with sternum (sternoclavicular joint) • Clavicle articulates with scapula (acromioclavicular joint) • Scapula held in place by muscle only • Upper limb attached to pectoral girdle at shoulder (glenohumeral joint) Principles of Human Anatomy and Physiology, 11e 79 Clavicle • The clavicle or collar bone lies horizontally in the superior and anterior part of thorax superior to the first rib and articulates with the sternum and the clavicle (Figure 8.2). • The clavicle, one of the most frequently broken bones in the body, transmits mechanical force from the upper limb to the trunk. Principles of Human Anatomy and Physiology, 11e 80 Clavicle (collarbone) • S-shaped bone with two curves – medial curve convex anteriorly/lateral one concave anteriorly • Extends from sternum to scapula above 1st rib • Fracture site is junction of curves • Ligaments attached to clavicle stabilize its position. Principles of Human Anatomy and Physiology, 11e 81 Scapula • The scapula or shoulder blade articulates with the clavicle and the humerus (Figure 8.3). • The scapulae articulate with other bones anteriorly, but are held in place posteriorly only by complex shoulder and back musculature. Principles of Human Anatomy and Physiology, 11e 82 Anterior Surface of Scapula • Subscapular fossa filled with muscle • Coracoid process for muscle attachment Principles of Human Anatomy and Physiology, 11e 83 Posterior Surface of Scapula • Triangular flat bone found in upper back region • Scapular spine ends as acromion process – a sharp ridge widening to a flat process • Glenoid cavity forms shoulder joint with head of humerus • Supraspinous & infraspinous fossa for muscular attachments Principles of Human Anatomy and Physiology, 11e 84 UPPER LIMB (EXTREMITY) • Each upper limb consists of 30 bones including the humerus, ulna, radius, carpals, metacarpals, and phalanges (Figure 8.4). Principles of Human Anatomy and Physiology, 11e 85 Upper Extremity • Each upper limb = 30 bones – humerus within the arm – ulna & radius within the forearm – carpal bones within the wrist – metacarpal bones within the palm – phalanges in the fingers • Joints – shoulder (glenohumeral), elbow, wrist, metacarpophalangeal, interphalangeal Principles of Human Anatomy and Physiology, 11e 86 Humerus • The humerus is the longest and largest bone of the upper limb (Figure 8.5). • It articulates proximally with the scapula and distally at the elbow with both the radius and ulna. Principles of Human Anatomy and Physiology, 11e 87 Humerus --- Proximal End • Part of shoulder joint • Head & anatomical neck • Greater & lesser tubercles for muscle attachments • Intertubercular sulcus or bicipital groove • Surgical neck is fracture site • Deltoid tuberosity • Shaft Principles of Human Anatomy and Physiology, 11e 88 Humerus --- Distal End anterior and posterior • Forms elbow joint with ulna and radius • Capitulum – articulates with head of radius • Trochlea – articulation with ulna • Olecranon fossa – posterior depression for olecranon process of ulna • Medial & lateral epicondyles – attachment of forearm muscles Principles of Human Anatomy and Physiology, 11e 89 Ulna and Radius • The ulna is located on the medial aspect of the forearm (Figure 8.6). • The radius is located on the lateral aspect (thumb side) of the forearm (Figure 8.6) • The radius and ulna articulate with the humerus at the elbow joint (Figure 8.7a), with each other (Figure 8.7b, c), and with three carpal bones. (Figure 8.8) Principles of Human Anatomy and Physiology, 11e 90 Ulna & Radius --- Proximal End • Ulna (on little finger side) – trochlear notch articulates with humerus & radial notch with radius – olecranon process forms point of elbow • Radius (on thumb side) – head articulates with capitulum of humerus & radial notch of ulna – tuberosity for muscle attachment Principles of Human Anatomy and Physiology, 11e 91 Ulna & Radius --- Proximal End • Ulna (on little finger side) – trochlear notch articulates with humerus & radial notch with radius – olecranon process forms point of elbow • Radius (on thumb side) – head articulates with capitulum of humerus & radial notch of ulna – tuberosity for muscle attachment Principles of Human Anatomy and Physiology, 11e 92 Elbow Joint • • • • Articulation of humerus with ulna and radius Ulna articulates with trochlea of humerus Radius articulates with capitulum of humerus Interosseous membrane between ulna & radius provides site for muscle attachment Principles of Human Anatomy and Physiology, 11e 93 Ulna and Radius - Distal End • Ulna --styloid process – head separated from wrist joint by fibrocartilage disc • Radius – forms wrist joint with scaphoid, lunate & triquetrum – forms distal radioulnar joint with head of ulna Principles of Human Anatomy and Physiology, 11e 94 Carpals, Metacarpal, and Phalanges • The eight carpal bones, bound together by ligaments, comprise the wrist (Figure. 8.8). • Five metacarpal bones are contained in the palm of each hand (Figure 8.8). • Each hand contains 14 phalanges, three in each finger and two in each thumb (Figure 8.8). Principles of Human Anatomy and Physiology, 11e 95 8 Carpal Bones (wrist) • Proximal row - lat to med – scaphoid - boat shaped – lunate - moon shaped – triquetrum - 3 corners – pisiform - pea shaped • Distal row - lateral to medial – trapezium - four sided – trapezoid - four sided – capitate - large head – hamate - hooked process • Carpal tunnel--tunnel of bone & flexor retinaculum Principles of Human Anatomy and Physiology, 11e 96 Metacarpals and Phalanges • Metacarpals – 5 total----#1 proximal to thumb – base, shaft, head – knuckles (metacarpophalangeal joints) • Phalanges – 14 total: each is called phalanx – proximal, middle, distal on each finger, except thumb – base, shaft, head Principles of Human Anatomy and Physiology, 11e 97 Hand Principles of Human Anatomy and Physiology, 11e 98 PELVIC (HIP) GIRDLE • The pelvic (hip) girdle consists of two hipbones (coxal bones) and provides a strong and stable support for the lower extremities, on which the weight of the body is carried (Figure 8.9). • Each hipbone (coxal bone) is composed of three separate bones at birth: the ilium, pubis, and ischium. • These bones eventually fuse at a depression called the acetabulum, which forms the socket for the hip joint (Figure 8.10a). Principles of Human Anatomy and Physiology, 11e 99 Pelvic Girdle and Hip Bones • Pelvic girdle = two hipbones united at pubic symphysis – articulate posteriorly with sacrum at sacroiliac joints • Each hip bone = ilium, pubis, and ischium – fuse after birth at acetabulum • Bony pelvis = 2 hip bones, sacrum and coccyx Principles of Human Anatomy and Physiology, 11e 100 The Ilium • The larger of the three components of the hip bone and articulates (fuses) with the ischium and pubis (Figure 8.10b,c). • Bone marrow aspiration or bone marrow biopsy are frequently performed on the iliac crest in adults. • The ischium is the inferior, posterior portion of the hip bone (Figure 8.10b,c). • The pubis is the anterior and inferior part of the hip bone (Figure 8.10b,c). Principles of Human Anatomy and Physiology, 11e 101 Ilium • • • • • Iliac crest and iliac spines for muscle attachment Iliac fossa for muscle attachment Gluteal lines indicating muscle attachment Sacroiliac joint at auricular surface & iliac tuberosity Greater sciatic notch for sciatic nerve Principles of Human Anatomy and Physiology, 11e 102 Ischium and Pubis • Ischium – ischial spine & tuberosity – lesser sciatic notch – ramus • Pubis – body – superior & inferior ramus – pubic symphysis is pad of fibrocartilage between 2 pubic bones Principles of Human Anatomy and Physiology, 11e 103 Pelvis • Pelvis = sacrum, coccyx & 2 hip bones • Pelvic brim – sacral promontory to symphysis pubis – separates false from true pelvis – false pelvis holds only abdominal organs • Inlet & outlet • Pelvic axis = path of babies head Principles of Human Anatomy and Physiology, 11e 104 True and False Pelves • Together with the sacrum and coccyx, the two hipbones (coxal bones) form the pelvis. • The greater (false) and lesser (true) pelvis are anatomical subdivisions of this basin-like structure (Figure 8.11a). • Pelvimetry, the measurement of the size of the inlet and the outlet of the birth canal, is important during pregnancy Principles of Human Anatomy and Physiology, 11e 105 Female and Male Skeletons • Male skeleton – larger and heavier – larger articular surfaces – larger muscle attachments • Female pelvis – wider & shallower – larger pelvic inlet & outlet – more space in true pelvis – pubic arch >90 degrees Principles of Human Anatomy and Physiology, 11e 106 COMPARISON OF FEMALE AND MALE PELVES • Male bones are generally larger and heavier than those of the female; the male’s joint surfaces also tend to be larger. • Muscle attachment points are more well-defined in the bones of a male than of a female due to the larger size of the muscles in males. • A number of anatomical differences exist between the pelvic girdles of females and those of males, primarily related to the need for a larger pelvic outlet in females to facilitate childbirth (Table 8.1). Principles of Human Anatomy and Physiology, 11e 107 Female Principles of Human Anatomy and Physiology, 11e Male 108 COMPARISON OF PECTORAL AND PELVIC GIRDLES • The pectoral girdle does not directly articulate with the vertebral column; the pelvic girdle does. • The pectoral girdle sockets are shallow and maximize movement; those of the pelvic girdle are deeper and allow less movement. • The structure of the pectoral girdle offers more movement than strength; the pelvic girdle, more strength than movement. Principles of Human Anatomy and Physiology, 11e 109 LOWER LIMB (EXTREMITY) • Each lower extremity is composed of 30 bones, including the femur, tibia, fibula, tarsals, metatarsals, and phalanges (Figure 8.12). Principles of Human Anatomy and Physiology, 11e 110 Lower Extremity • Each lower limb = 30 bones – femur and patella within the thigh – tibia & fibula within the leg – tarsal bones in the foot – metatarsals within the forefoot – phalanges in the toes • Joints – hip, knee, ankle – proximal & distal tibiofibular – metatarsophalangeal Principles of Human Anatomy and Physiology, 11e 111 Femur • The femur or thighbone is the largest, heaviest, and strongest bone of the body (Figure 8.13a, b). • It articulates with the hip bone and the tibia. – head articulates with acetabulum (attached by ligament of head of femur) – medial & lateral condyles articulate with tibia • neck is common fracture site • greater & lesser trochanters, linea aspera, & gluteal tuberosity-- muscle attachments • patellar surface is visible anteriorly between condyles Principles of Human Anatomy and Physiology, 11e 112 Femur Principles of Human Anatomy and Physiology, 11e 113 Patella • The patella or kneecap is a sesamoid bone located anterior to the knee joint (Figure 8.14). • It functions to increase the leverage of the tendon of the quadriceps femoris muscle, to maintain the position of the tendon when the knee is bent, and to protect the knee joint. • Patellofemoral stress syndrome is a common knee problem in runners. Principles of Human Anatomy and Physiology, 11e 114 Patella • triangular sesamoid bone • increases leverage of quadriceps femoris tendon Principles of Human Anatomy and Physiology, 11e 115 Tibia and Fibula • The tibia or shinbone is the larger, medial, weight-bearing bone of the leg (Figure 8.15). • The fibula is parallel and lateral to the tibia (Figure 8.15). Principles of Human Anatomy and Physiology, 11e 116 Tibia and Fibula Principles of Human Anatomy and Physiology, 11e Tibia • medial & larger bone of leg • weight-bearing bone • lateral & medial condyles • tibial tuberosity for patellar lig. • proximal tibiofibular joint • medial malleolus at ankle 117 Tibia and Fibula Fibula • not part of knee joint • muscle attachment only • lateral malleolus at ankle lateral view of tibia Principles of Human Anatomy and Physiology, 11e 118 Tarsals, Metatarsals, and Phalanges • Seven tarsal bones constitute the ankle and share the weight associated with walking (Figure 8.16). • Five metatarsal bones are contained in the foot (Figure 8.16). • Fractures of the metatarsals are common among dancers, especially ballet dancers. • The arrangement of phalanges in the toes is the same as that described for the fingers and thumb above - fourteen bones in each foot (Figure 8.16). Principles of Human Anatomy and Physiology, 11e 119 Tarsus • Proximal region of foot (contains 7 tarsal bones) • Talus = ankle bone (articulates with tibia & fibula) • Calcaneus - heel bone • Cuboid, navicular & 3 cuneiforms Principles of Human Anatomy and Physiology, 11e 120 Metatarsus and Phalanges • Metatarsus – midregion of the foot – 5 metatarsals (1 is most medial) – each with base, shaft and head • Phalanges – distal portion of the foot – similar in number and arrangement to the hand – big toe is hallux Principles of Human Anatomy and Physiology, 11e 121 Arches of the Foot • The bones of the foot are arranged in two non-rigid arches that enable the foot to support the weight of the body; provide an ideal distribution of body weight over the hard and soft tissues, and provide leverage while walking (Figure 8.17). • Flatfoot, clawfoot, and clubfoot are caused by decline, elevation, or rotation of the medial longitudinal arches. Principles of Human Anatomy and Physiology, 11e 122 Arches of the Foot • Function – distribute body weight over foot – yield & spring back when weight is lifted • Longitudinal arches along each side of foot • Transverse arch across midfoot region – navicular, cuneiforms & bases of metatarsals Principles of Human Anatomy and Physiology, 11e 123 Clinical Problems • Flatfoot – weakened ligaments allow bones of medial arch to drop • Clawfoot – medial arch is too elevated • Hip fracture – 1/2 million/year in US – osteoporosis – arthroplasty Principles of Human Anatomy and Physiology, 11e 124 DEVELOPMENTAL ANATOMY OF THE SKELETAL SYSTEM • Bone forms from mesoderm by intramembranous or endochondrial ossification. (Figure 6.6) • The skull begins development during the fourth week after fertilization (Figure 8.18a) • Vertebrae are derived from portions of cube-shaped masses of mesoderm called somites (Figure 10.10) • Around the fifth week of embryonic life, extremities develop from limb buds, which consist of mesoderm and ectoderm (Figure8.18b). • By the sixth week, a constriction around the middle portion of the limb buds produces hand plates and foot plates, which will become hands and feet. (Figure8.18c) • By the seventh week, the arm, forearm and hand are evident in the upper limb bud and the thigh, leg, and foot appear in the lower limb bud. (Figure8.18d) • By the eighth week the limb buds have developed into limbs. (Figure8.18e) Principles of Human Anatomy and Physiology, 11e 125 Principles of Human Anatomy and Physiology, 11e 126 Principles of Human Anatomy and Physiology, 11e 127 end Principles of Human Anatomy and Physiology, 11e 128 Chapter 9 Joints Lecture Outline Principles of Human Anatomy and Physiology, 11e 129 INTRODUCTION • A joint (articulation or arthrosis) is a point of contact between two or more bones, between cartilage and bones, or between teeth and bones. • The scientific study of joints is called arthrology. Principles of Human Anatomy and Physiology, 11e 130 Chapter 9 Joints • Joints hold bones together but permit movement • Point of contact – between 2 bones – between cartilage and bone – between teeth and bones • Arthrology = study of joints • Kinesiology = study of motion Principles of Human Anatomy and Physiology, 11e 131 Classification of Joints • Structural classification is based on the presence or absence of a synovial (joint) cavity and type of connecting tissue. Structurally, joints are classified as – fibrous, cartilaginous, or synovial. • Functional classification based upon movement: – immovable = synarthrosis – slightly movable = amphiarthrosis – freely movable = diarthrosis Principles of Human Anatomy and Physiology, 11e 132 Fibrous Joints • Lack a synovial cavity • Bones held closely together by fibrous connective tissue • Little or no movement (synarthroses or amphiarthroses) • 3 structural types – sutures – syndesmoses – gomphoses Principles of Human Anatomy and Physiology, 11e 133 Sutures • Thin layer of dense fibrous connective tissue unites bones of the skull • Immovable (synarthrosis) • If fuse completely in adults is synostosis Principles of Human Anatomy and Physiology, 11e 134 Syndesmosis • Fibrous joint – bones united by ligament • Slightly movable (amphiarthrosis) • Anterior tibiofibular joint and Interosseous membrane Principles of Human Anatomy and Physiology, 11e 135 Gomphosis • Ligament holds cone-shaped peg in bony socket • Immovable (synarthrosis) • Teeth in alveolar processes Principles of Human Anatomy and Physiology, 11e 136 Cartilaginous Joints • • • • Lacks a synovial cavity Allows little or no movement Bones tightly connected by fibrocartilage or hyaline cartilage 2 types – synchondroses – symphyses Principles of Human Anatomy and Physiology, 11e 137 Synchondrosis • Connecting material is hyaline cartilage • Immovable (synarthrosis) • Epiphyseal plate or joints between ribs and sternum Principles of Human Anatomy and Physiology, 11e 138 Symphysis • Fibrocartilage is connecting material • Slightly movable (amphiarthroses) • Intervertebral discs and pubic symphysis Principles of Human Anatomy and Physiology, 11e 139 • Synovial cavity separates articulating bones • Freely moveable (diarthroses) • Articular cartilage – reduces friction – absorbs shock • Articular capsule – surrounds joint – thickenings in fibrous capsule called ligaments • Synovial membrane – inner lining of capsule Principles of Human Anatomy and Physiology, 11e Synovial Joints 140 Example of Synovial Joint • Joint space is synovial joint cavity • Articular cartilage covering ends of bones • Articular capsule Principles of Human Anatomy and Physiology, 11e 141 Articular Capsule • The articular capsule surrounds a diarthrosis, encloses the synovial cavity, and unites the articulating bones. • The articular capsule is composed of two layers - the outer fibrous capsule (which may contain ligaments) and the inner synovial membrane (which secretes a lubricating and jointnourishing synovial fluid) (Figure 9.3). • The flexibility of the fibrous capsule permits considerable movement at a joint, whereas its great tensile strength helps prevent bones from dislocating. • Other capsule features include ligaments and articular fat pads (Figure 9.3). Principles of Human Anatomy and Physiology, 11e 142 • Synovial Membrane Special – secretes synovial fluid Features containing slippery hyaluronic acid – brings nutrients to articular cartilage • Accessory ligaments – extracapsular ligaments • outside joint capsule – intracapsular ligaments • within capsule • Articular discs or menisci – attached around edges to capsule – allow 2 bones of different shape to fit tightly – increase stability of knee - torn cartilage • Bursae = saclike structures between structures – skin/bone or tendon/bone or ligament/bone Principles of Human Anatomy and Physiology, 11e 143 Nerve and Blood Supply • Nerves to joints are branches of nerves to nearby muscles • Joint capsule and ligaments contain pain fibers and sensory receptors • Blood supply to the structures of a joint are branches from nearby structures – supply nutrients to all joint tissues except the articular cartilage which is supplied from the synovial fluid Principles of Human Anatomy and Physiology, 11e 144 Sprain versus Strain • Sprain – twisting of joint that stretches or tears ligaments – no dislocation of the bones – may damage nearby blood vessels, muscles or tendons – swelling & hemorrhage from blood vessels – ankle if frequently sprained • Strain – generally less serious injury – overstretched or partially torn muscle Principles of Human Anatomy and Physiology, 11e 145 Bursae and Tendon Sheaths • Bursae – fluid-filled saclike extensions of the joint capsule – reduce friction between moving structures • skin rubs over bone • tendon rubs over bone • Tendon sheaths – tubelike bursae that wrap around tendons at wrist and ankle where many tendons come together in a confined space • Bursitis – chronic inflammation of a bursa Principles of Human Anatomy and Physiology, 11e 146 TYPES OF MOVEMENT AT SYNOVIAL JOINTS Principles of Human Anatomy and Physiology, 11e 147 Gliding Movements • Gliding movements occur when relatively flat bone surfaces move back and forth and from side to side with respect to one another (Figure 9.4). • In gliding joints there is no significant alteration of the angle between the bones. • Gliding movements occur at plantar joints. Principles of Human Anatomy and Physiology, 11e 148 Angular Movements • In angular movements there is an increase or a decrease in the angle between articulating bones. – Flexion results in a decrease in the angle between articulating bones (Figure 9.5). • Lateral flexion involves the movement of the trunk sideways to the right or left at the waist. The movement occurs in the frontal plane and involves the intervertebral joints (Figure 9.5g). – Extension results in an increase in the angle between articulating bones (Figure 9.5). – Hyperextension is a continuation of extension beyond the anatomical position and is usually prevented by the arrangement of ligaments and the anatomical alignment of bones (Figures 9.5a, b, d, e). Principles of Human Anatomy and Physiology, 11e 149 Flexion, Extension & Hyperextension Principles of Human Anatomy and Physiology, 11e 150 Abduction, Adduction, and Circumduction • Abduction refers to the movement of a bone away from the midline (Figure 9.6a-c). • Adduction refers to the movement of a bone toward the midline (Figure 9.6d). • Circumduction refers to movement of the distal end of a part of the body in a circle (Figure 9.7). – Circumduction occurs as a result of a continuous sequence of flexion, abduction, extension, and adduction. – Condyloid, saddle, and ball-and-socket joints allow circumduction. • In rotation, a bone revolves around its own longitudinal axis (Figure 9.8a). Principles of Human Anatomy and Physiology, 11e 151 Abduction and Adduction Condyloid joints Ball and Socket joints Principles of Human Anatomy and Physiology, 11e 152 Circumduction • Movement of a distal end of a body part in a circle • Combination of flexion, extension, adduction and abduction • Occurs at ball and socket, saddle and condyloid joints Principles of Human Anatomy and Physiology, 11e 153 Pivot and ball-and-socket joints permit rotation. • If the anterior surface of a bone of the limb is turned toward the midline, medial rotation occurs. If the anterior surface of a bone of the limb is turned away from the midline, lateral rotation occurs (Figure 9.8 b&c). Principles of Human Anatomy and Physiology, 11e 154 Rotation • Bone revolves around its own longitudinal axis – medial rotation is turning of anterior surface in towards the midline – lateral rotation is turning of anterior surface away from the midline • At ball & socket and pivot type joints Principles of Human Anatomy and Physiology, 11e 155 Special Movements • Elevation is an upward movement of a part of the body (Figure 9.9a). • Depression is a downward movement of a part of the body (Figure 9.9b). • Protraction is a movement of a part of the body anteriorly in the transverse plane (Figure 9.9c). • Retraction is a movement of a protracted part back to the anatomical position (Figure 9.9d). Principles of Human Anatomy and Physiology, 11e 156 Special Movements of Mandible • • • • Principles of Human Anatomy and Physiology, 11e Elevation = upward Depression = downward Protraction = forward Retraction = backward 157 Special Movements • Inversion is movement of the soles medially at the intertarsal joints so that they face away from each other (Figure 9.9e). • Eversion is a movement of the soles laterally at the intertarsal joints so that they face away from each other (Figure 9.9f). • Dorsiflexion refers to bending of the foot at the ankle in the direction of the superior surface (Figure 9.9g). • Plantar flexion involves bending of the foot at the ankle joint in the direction of the plantar surface (Figure 9.9g). Principles of Human Anatomy and Physiology, 11e 158 Special Hand & Foot Movements • • • • • • Principles of Human Anatomy and Physiology, 11e Inversion Eversion Dorsiflexion Plantarflexion Pronation Supination 159 Special Movements • Supination is a movement of the forearm at the proximal and distal radioulnar joints in which the palm is turned anteriorly or superiorly (Figure 9.9h). • Pronation is a movement of the forearm at the proximal and distal radioulnar joints in which the distal end of the radius crosses over the distal end of the ulna and the palm is turned posteriorly or inferiorly (Figure 9.9h). Principles of Human Anatomy and Physiology, 11e 160 Special Movements • Opposition is the movement of the thumb at the carpometacarpal joint in which the thumb moves across the palm to touch the tips of the finger on the same hand. • Review – A summary of the movements that occur at synovial joints is presented in Table 9.1. • A dislocation or luxation is a displacement of a bone from a joint. Principles of Human Anatomy and Physiology, 11e 161 TYPES OF SYNOVIAL JOINTS • Planar joints permit mainly side-to-side and back-and-forth gliding movements (Figure 9.10a). These joints are nonaxial. Principles of Human Anatomy and Physiology, 11e 162 Planar Joint • Bone surfaces are flat or slightly curved • Side to side movement only • Rotation prevented by ligaments • Examples – intercarpal or intertarsal joints – sternoclavicular joint – vertebrocostal joints Principles of Human Anatomy and Physiology, 11e 163 TYPES OF SYNOVIAL JOINTS • A hinge joint contains the convex surface of one bone fitting into a concave surface of another bone (Figure 9.10b). Movement is primarily flexion or extension in a single plane.. Principles of Human Anatomy and Physiology, 11e 164 Hinge Joint • Convex surface of one bones fits into concave surface of 2nd bone • Uniaxial like a door hinge • Examples – Knee, elbow, ankle, interphalangeal joints • Movements produced – flexion = decreasing the joint angle – extension = increasing the angle – hyperextension = opening the joint beyond the anatomical position Principles of Human Anatomy and Physiology, 11e 165 TYPES OF SYNOVIAL JOINTS • In a pivot joint, a round or pointed surface of one bone fits into a ring formed by another bone and a ligament (Figure 9.10c). Movement is rotational and monaxial. Principles of Human Anatomy and Physiology, 11e 166 Pivot Joint • Rounded surface of bone articulates with ring formed by 2nd bone & ligament • Monoaxial since it allows only rotation around longitudinal axis • Examples – Proximal radioulnar joint • supination • pronation – Atlanto-axial joint • turning head side to side “no” Principles of Human Anatomy and Physiology, 11e 167 TYPES OF SYNOVIAL JOINTS • In an condyloid joint, an oval-shaped condyle of one bone fits into an elliptical cavity of another bone (Figure 9.10d). Movements are flexion-extension, abduction-adduction, and circumduction. Principles of Human Anatomy and Physiology, 11e 168 Condyloid or Ellipsoidal Joint • Oval-shaped projection fits into oval depression • Biaxial = flex/extend or abduct/adduct is possible • Examples – wrist and metacarpophalangeal joints for digits 2 to 5 Principles of Human Anatomy and Physiology, 11e 169 TYPES OF SYNOVIAL JOINTS • A saddle joint contains one bone whose articular surface is saddle-shaped and another bone whose articular surface is shaped like a rider sitting in the saddle. Movements are flexion-extension, abduction-adduction, and circumduction (Figure 9.10e). Principles of Human Anatomy and Physiology, 11e 170 Saddle Joint • One bone saddled-shaped; other bone fits as a person would sitting in that saddle • Biaxial – Circumduction allows tip of thumb travel in circle – Opposition allows tip of thumb to touch tip of other fingers • Example – trapezium of carpus and metacarpal of the thumb Principles of Human Anatomy and Physiology, 11e 171 TYPES OF SYNOVIAL JOINTS • In a ball-and-socket joint, the ball-shaped surface of one bone fits into the cuplike depression of another (Figure 9.10f). Movements are flexion-extension, abductionadduction, rotation, and circumduction. Principles of Human Anatomy and Physiology, 11e 172 Ball and Socket Joint • Ball fitting into a cuplike depression • Multiaxial – flexion/extension – abduction/adduction – rotation • Examples (only two!) – shoulder joint – hip joint Principles of Human Anatomy and Physiology, 11e 173 SELECTED JOINTS OF THE BODY Principles of Human Anatomy and Physiology, 11e 174 Tempromandibular Joint (TMJ) (Exhibit 9.1 and Figure 9.11) • The TMJ is a combined hinge and planar joint formed by the condylar process of the mandible, the mandibular fossa, and the articular tubercle of the temporal bone. • Movements include opening and closing and protraction and retraction of the jaw. • When dislocation occurs, the mouth remains open. Principles of Human Anatomy and Physiology, 11e 175 Temporomandibular Joint lateral medial Principles of Human Anatomy and Physiology, 11e • • • • • Synovial joint Articular disc Gliding above disc Hinge below disc Movements – depression – elevation – protraction – retraction 176 Temporoman-dibular Joint • • • • • Principles of Human Anatomy and Physiology, 11e Synovial joint Articular disc Gliding above disc Hinge below disc Movements – depression – elevation – protraction – retraction 177 Shoulder Joint (Exhibit 9.2 and Figure 9.12). • This is a ball-and-socket joint formed by the head of the humerus and the glenoid cavity of the scapula. • Movements at the joint include flexion, extension, abduction, adduction, medial and lateral rotation, and circumduction of the arm . • This joint shows extreme freedom of movement at the expense of stability. • Rotator cuff injury and dislocation or separated shoulder are common injuries to this joint. Principles of Human Anatomy and Physiology, 11e 178 Shoulder Joint • Head of humerus and glenoid cavity of scapula • Ball and socket • All types of movement Principles of Human Anatomy and Physiology, 11e 179 Glenohumeral (Shoulder) Joint • Articular capsule from glenoid cavity to anatomical neck • Glenoid labrum deepens socket • Many nearby bursa (subacromial) Principles of Human Anatomy and Physiology, 11e 180 Supporting Structures at Shoulder • Associated ligaments strengthen joint capsule • Transverse humeral ligament holds biceps tendon in place Principles of Human Anatomy and Physiology, 11e 181 Rotator Cuff Muscles • Attach humerus to scapula • Encircle the joint supporting the capsule • Hold head of humerus in socket Principles of Human Anatomy and Physiology, 11e 182 Elbow Joint (Exhibit 9.3 and Figure 9.13) • This is a hinge joint formed by the trochlea of the humerus, the trochlear notch of the ulna, and the head of the radius. • Movements at this joint are flexion and extension of the forearm. • Tennis elbow, little elbows, and dislocation of the radial head are common injuries to this joint. Principles of Human Anatomy and Physiology, 11e 183 Articular Capsule of the Elbow Joint lateral aspect medial aspect • Radial annular ligament hold head of radius in place • Collateral ligaments maintain integrity of joint Principles of Human Anatomy and Physiology, 11e 184 Hip Joint (Exhibit 9.4 and Figure 9.14) • This ball-and-socket joint is formed by the head of the femur and the acetabulum of the hipbone. • Movements at this joint include flexion, extension, abduction, adduction, circumduction, and medial and lateral rotation of the thigh. • This is an extremely stable joint due to the bones making up the joint and the accessory ligaments and muscles. Principles of Human Anatomy and Physiology, 11e 185 Hip Joint • Head of femur and acetabulum of hip bone • Ball and socket type of joint • All types of movement possible Principles of Human Anatomy and Physiology, 11e 186 Hip Joint Structures • Acetabular labrum • Ligament of the head of the femur • Articular capsule Principles of Human Anatomy and Physiology, 11e 187 Hip Joint Capsule • Dense, strong capsule reinforced by ligaments – iliofemoral ligament – ischiofemoral ligament – pubofemoral ligament • One of strongest structures in the body Principles of Human Anatomy and Physiology, 11e 188 Knee Joints (Exhibit 9.5 and Figure 9.15) • This is the largest and most complex joint of the body and consists of three joints within a single synovial cavity. • Movements at this joint include flexion, extension, slight medial rotation, and lateral rotation of the leg in a flexed position. • Some common injuries are rupture of the tibial colateral ligament and a dislocation of the knee. • Refer to Tables 9.3 and 9.4 to integrate bones, joint classifications, and movements. Principles of Human Anatomy and Physiology, 11e 189 Tibiofemoral Joint • Between femur, tibia and patella • Hinge joint between tibia and femur • Gliding joint between patella and femur • Flexion, extension, and slight rotation of tibia on femur when knee is flexed Principles of Human Anatomy and Physiology, 11e 190 Tibiofemoral Joint • Articular capsule – mostly ligs & tendons • Lateral & medial menisci = articular discs • Many bursa • Vulnerable joint • Knee injuries damage ligaments & tendons since bones do not fit together well Principles of Human Anatomy and Physiology, 11e 191 External Views of Knee Joint • Patella is part of joint capsule anteriorly • Rest of articular capsule is extracapsular ligaments – Fibular and tibial collateral ligaments Principles of Human Anatomy and Physiology, 11e 192 Intracapsular Structures of Knee • Medial meniscus – C-shaped fibrocartilage • Lateral meniscus – nearly circular • Posterior cruciate ligament • Anterior cruciate ligament Principles of Human Anatomy and Physiology, 11e 193 FACTORS AFFECTING CONTACT AND RANGE OF MOTION AT SYNOVIAL JOINTS • • • • • • • • Structure and shape of the articulating bone Strength and tautness of the joint ligaments Arrangement and tension of the muscles Contact of soft parts Hormones Disuse AGING AND JOINTS Various aging effects on joints include decreased production of synovial fluid, a thinning of the articular cartilage, and loss of ligament length and flexibility. • The effects of aging on joints are due to genetic factors as well as wear and tear on joints. Principles of Human Anatomy and Physiology, 11e 194 Arthroscopy & Arthroplasty • Arthroscopy = examination of joint – instrument size of pencil – remove torn knee cartilages & repair ligaments – small incision only • Arthroplasty = replacement of joints – total hip replaces acetabulum & head of femur – plastic socket & metal head – knee replacement common Principles of Human Anatomy and Physiology, 11e 195 Techniques for cartilage replacement • In cartilage transplantation chondrocytes are removed from the patient, grown in culture, and then placed in the damaged joint. • Eroded cartilage may be replaced with synthetic materials • Researchers are also examining the use of stem cells to replace cartilage. Principles of Human Anatomy and Physiology, 11e 196 DISORDERS: HOMEOSTATIC IMBALANCES: Rheumatism and Arthritis • Osteoarthritis is a degenerative joint disease commonly known as “wear-and-tear” arthritis. It is characterized by deterioration of articular cartilage and bone spur formation. It is noninflammatory and primarily affects weight-bearing joints. • Gouty arthritis is a condition in which sodium urate crystals are deposited in soft tissues of joints, causing inflammation, swelling, and pain. If not treated, bones at affected joints will eventually fuse, rendering the joints immobile. Principles of Human Anatomy and Physiology, 11e 197 Hip Replacement Principles of Human Anatomy and Physiology, 11e 198 DISORDERS: HOMEOSTATIC IMBALANCES: • Lyme disease is a bacterial disease which is transmitted by deer ticks. Symptoms include joint stiffness, fevers, chills, headache, and stiff neck. • Ankylosing spondylitis affects joints between the vertebrae and between the sacrum and hip bone. Its cause is unknown. • Ankle Sprains and Fractures: The ankle is the most frequently injured major joint. Sprains are the most common injury to the ankle; they are treated with RICE. A fracture of the distal leg that involves both the medial and lateral malleoli is called a Pott’s fracture. Principles of Human Anatomy and Physiology, 11e 199 Rheumatoid Arthritis • • • • Principles of Human Anatomy and Physiology, 11e Autoimmune disorder Cartilage attacked Inflammation, swelling & pain Final step is fusion of joint 200 Osteoarthritis • Degenerative joint disease – aging, wear & tear • Noninflammatory---no swelling – only cartilage is affected not synovial membrane • Deterioration of cartilage produces bone spurs – restrict movement • Pain upon awakening--disappears with movement Principles of Human Anatomy and Physiology, 11e 201 Gouty Arthritis • Urate crystals build up in joints---pain – waste product of DNA & RNA metabolism – builds up in blood – deposited in cartilage causing inflammation & swelling • Bones fuse • Middle-aged men with abnormal gene Principles of Human Anatomy and Physiology, 11e 202 end Principles of Human Anatomy and Physiology, 11e 203