Intro to the Skeletal System. Chap 6:

Bones are composed of several different tissues working together * osseous tissue * cartilage * dense connective tissue * epithelium * adipose tissue * nervouse tissue
All of the bones and the cartilages,

Functions: * supports soft tissues and provides attachment points for tendons of skeletal muscles * protects the most important internal organs * assists in movement by acting as levers for skeletal muscles * osseous tissue stores and releases minerals, particularly calcium and phosphorus * red marrow within bones produces blood cells * yellow marrow within bones stores triglycerides, a source of potential energy reserve
Classification:
-longbones -- greater length than width
- short bones -- nearly equal in l & w
- flat bones -- thin
- irregular bones -- complex shapes
- sesamoid bones -- shaped like a sesame seed
Long bone anatomy: * -Regions of a long bone * Diaphysis (Shaft) * Medullay cavity (inside shaft) * 2 Epiphyses (proximal and distal) * 2 Metaphyses (join diaphysis and epiphysis with epiphyseal plate, or line once growth stops) * -Surface tissues * Endosteum * Periosteum * Articular cartilage *

Osseous Tissue * -Extra cellular matrix of connective tissue * Water * Collagen fibers- gives property of flexibility and tensile strength * Crystallized mineral salts of hydroxyapatities – gives property of hardness * -Four principal type of cells * Osteogenic- undifferentiated, give rise to osteoblasts (not as important) * Osteoblasts- * Osteocytes- * Osteoclasts- Bone destroying

Types of Osseous Tissue * -compact bone * forms external layer of all bones and comprises most of the diaphysis of long bones * -spongy bone * forms interior of short, flat, irregular, and sesamoid bones, most of epiphysis of long
Compact bone structure * -osteons form repeating structural units aligned in same direction, with few spaces * central canal with blood and lymph vessels and nerves***need to know * concentric lamellae of extracellular matrix***need to know * -Perforating canals penetrate transverse through osteons from periosteum***need to know
Spongy bone structure * -Has more space than compact. Trabeculae- Holes like a sponge ** need to know * Red marrow is made in spongy bone
Blood and Nerve Supply to Bones * -Highly vascular with blood vessels passing into bones from periosteal artery * Nutrient foramen- leads to perforating canal through periosteum * Nutrient artery and vein- diaphysis and parts of metaphysis * Metaphyseal artery and vein * Epiphyseal artery and vein * -Sensory nerves accompany blood vessels

Type of Bone Formation * -Ossification * Initial formation of bones before birth * Growth of bones until adult size reached * Remodeling and repair of bones * -Intramembranous ossification * Bone develops directly within sheet-like mesenchyme layers * Flat bones of skull, mandible, and clavicle * -Endochondral ossification * Most bones in body form within hyaline cartilage develops mesenchyme

** Must know ** primary and secondary ossification. How do you grow and where. General.
Factors influencing bone growth and remodeling * -growth and maintenance of bones depends on adequate nutrition ( Energy, Calcium, Many Vitamins) * -Hormones * Growth hormone and IGF’s stimulate bone growth * Thyroid hormone and insulin also promote bone growth * Sex steroids (estrogen and testosterone) stimulate bone growth in gender specific patterns * Epiphyseal plate closure results from higher levels of estrogens.
Chapter 7 Axial Skeleton Intro * musculoskeletal system * -Bones of skeleton * 206 in adult * More in infants and children as some fuse later * -Skeletal muscles * -Joints
Bone surface markings * In addition to names, bones have unique structural features that serve as anatomical landmarks, and also have various functional roles * -Two major types of surface markings * depressions and openings- usually allow passage of blood vessels and nerves or help form joints. * Processes- projections that either help form joints or serve as attachment points for ligaments and tendons. * P 186

Skull
Anatomy
* Contains 22 bones in two categories * 8 cranial bones * 14 facial bones * Immovable joints are called sutures * Foramina and fissures form openings for blood vessels and nerves
Functions
* Protects the brain and special sensory organs * Forms the framework for the face * Provides attachment of membranes and muscles * Protects and supports entrances of the digestive and respiratory tract *** need to know!!!**
Cranial bones: frontal bone * forms the frontal and the anterior cranial floor, helps form the orbits, and houses the frontal sinuses * major landmarks * supraorbital margin (eyebrows) * supraorbital foramen * frontal sinuses
Cranial bones: Parietal bones * largest of cranial bones
Cranial Bone: Temporal Bones * -most complicated * -form the inferior, lateral sides of the skull and cranial floor * -major landmarks * zygomatic process * mandibular fossa * external auditory meatus * mastoid process * styloid process * -Petrous portion forms floor * Internal auditory meatus * Carotid foramen * Jugular foramen
Cranial bones: sphenoid bone * lies in the middle of the base of the skull and articulates with all other cranial bones * major landmarks * sella turcia- sticks up in skull(IMPORANT. Helps protect pituitary gland p.190) with hypophyseal fossa
Cranial bones: ethmoid bone * Nasal concha * Remember how to identify it. (bones inside of nose)
Facial Bones: Nasal Bone * forms bridge of nose * tiny bones
Facial Bones: Maxilae bones * forms upper jaw bone and hard palate
Facial Bones: Zygomatic bones * form the cheeks and part of the orbits * major landmark * forms part of the zygomatic arch with zygomatic process of temporal bone (Small bone above lower jaw line)
Facial Bones: Lacrimal bone * contributes to the orbits; smallest facial bone * Lacrimal fossa (tear duct) * Inside of the eye
Facial Bones with no major landmarks * palatine bones * form the posterior part of the hard palate, and part of the nasal cavity and orbits * septum of nose
Facial bones: mandible bone * freely movable of lower jawbone * Landmarks * Body * Ramus (Plural= rami) curved projection * Condylar process** * Coronoid process** * Mandibular notch **
Unique skull features- orbits * holds eyeball and related structures * formed by three cranial and four facial bones
Unique skull features- Paranasal sinuses * cavities lined by mucous membranes * found in frontal, sphenoid, ethmoid and maxillary bones * functions: * Lighten the skull * Increase the surface area
Unique skull features: sutures * immovable joints * where skull comes together
Unique skull features: Fontanels * gap between the cranial bones when a baby is born
Hyoid Bone * unique because it does not articulate with any other bone * supports the tongue and provides attachment for some tongue and provides attachment for some tongue muscles and for some muscles of the pharynx and neck * major landmarks * body * lesser horns
Vertebra Column * Series of vertebrae that surround and project the spinal cord, support the head, and serve as a point of attachment for the ribs, pelvic girdle, and back muscles. * 7 cervical vertebrae (C 1-7) * 12 thoracic vertebrae (T 1-12) * 5 lumbar vertebrae (L 1-5) * Sacrum * Coccyx
Vertebral Column * 4 normal curves increase strength, absorb shock, help maintain balance, and protect against vertebral fracture * fibrocartilage intervertebral discs occur between bodies of adjacent vertebrae, allowing movement and absorbing shock
Typical Vertebral Structures * Body – weight bearing portion * Vertebral Arch- surrounds spinal cord * Processes * 1 spinous process * 2 transverse processes * 2 superior articular processes * 2 inferior articular processes * Foramen * Vetebral foramen * Intervertebral foramen (between two vertebrae)
Cervical Vertebrae * Transverse process has a transverse foramen through which the vertebral arteries pass to supply blood to the brain * Atlas (C1) * Articulates with occipital condyles of the skull with modifications for movement (no head “yes”) * Lacks a body and spinous process * Axis (C2) * Has the dens** which projects superiorly to act as a pivot for the roation of the atlas ( shake head “no”)
Thoracic Vertebrae * Articulate with ribs * Bodies have demifacets for articulation * Transverse processes have facets for articulation
Lumbar Vertebrae * Short, Thick processes * Largest and strongest vertebrae
Sacrum and Coccyx * Sacrum * formed by the fusion of the five sacral vertebrae * articulates laterally with the two hip bones * Coccyx * Formed by the fusion of four coccygeal vertebrae * Differences between male and female (mens points more anteriorly)
Thoracic Cage * 12 pair of ribs
Sternum
* Three regions * Manubrium (Square piece at very top) * Body * Xiphoid process (almost triangular where ribs come together) * Major landmarks * Sternal angle * Suprasternal notch * Clavicular notches
Rib Classification * True Ribs ( 1st seven pairs) * Articulate directly with sternum by hyaline costal cartilage * False Ribs (remaining 5 pairs) * Do not attach directly, or at all, with sternum * Cartilages of the 8th,9th,and 10th pairs connect to each other and coastal cartilage of the 7th pair * Floating ribs- 11th and 12th pairs have no anterior articulation, only posteriorly to thoracic vertebrae.
Rib
* Structure * Head * Neck * Body * Intercostal spaces- between ribs * Costal cartilage- anterior
Appendicular skeleton * appendicular skeleton is composed of the upper and lower limbs, and the girdles that attach to the limbs
Pectoral Girdle * composed of clavicle and scapula * articulates with sternum anteriorly * does not articulate with vertebrae or each other posteriorly; instead stabilized by group of large muscles.
Pectoral Girdle: Clavicle * Slender S- shaped collar bone * Articulates medially with the manubrium of the sternum * Articulates with the acromion of the scapula * Major Landmark * Sternal end * Acromial end****
Pectoral Girdle: Scapula * Major site of muscle attachments, and connects to upper limb to the axial skeleton * Major landmarks * Spine * Acromion * Glenoid process * Coracoid Process
Upper Limb * Consists of the following regions (number of individual bones) * Arm (1) * Forearm (2) * Wrist (8) * Palm of hand (5) * Fingers (14)
Upper Limb: Humerus * Longest and largest bone in upper limb * Articulates proximally with glenoid cavity * Articulates distally with radius and ulna at elbow joint * Major landmarks * Proximal End * Head * Neck * Tubercle (Greater and Lesser – one is larger than other) * Deltoid Tuberosity- rough patch muscle attaches to * Distal End * Radial Fossa * Coronoid Fossa * Trochlea * Capitulum * Olecranon Fossa (back of arm) * Medial and lateral Epicondyle (protrusion on side of arm near elbow)
Be sure to figure out which bone your looking at if arm left or right remember anatomical position hands at side with thumbs out. (Medial- Closest to midline)
Upper Limb: Ulna and Radius
Radius is always on thumb side (Lateral) ulna is always medial * articulate proximally at elbow with Humerus * articulat distally with three of the carpals * connected by interosseous membrane * Major Landmark * Ulna: * Olecranon (big back of arm near elbow) * Coronoid process * Styloid Process (distal end of wrist) * Radius: * Proximal end: head (looks like head of nail) * Neck * Radial tuberosity- Roughened end * Styloid Process
Upper Limb: Carpals, Metacarpals, and Phalanges * Carpus includes 8 carpal bones * Concave space formed by several carpals and fibrous flexor retinaculum forms carpal tunnel * Surrounds tendons of finger muscles and medial nerve * -Metacarpals * Pinky finger always is numbered 5, thumb is 1 * Proximal phalanx, Distal phalanx
Pelvic Girdle * Composed of two coxal bones (Hip bones) formed by fusion of three bones * Ilium * Ischium * Pubis * Form Pelvis * Supports the vertebral column * Protects the lower abdominal and pelvic cavity * Remember Pubic symphysis, sacroiliac joint, acetabulum, obturator foramen
Pelvic Girdle: Coxal Bone * Acetabulum * Formed by all 3 bones; articulates with femur head * Obtuator Foramen * Formed by ischium and pubis
Pelvic Girdle: Ilium * Largest and major site of muscle attachment * Landmarks: * Iliac Crest * Greater sciatic notch * Spines (2 anterior, 2 posterior, 2 superior and 2 inferior) **
Pelvic Girdle: Ischium * Inferior, posterior part of hip bone * Landmarks: * Body * Ramus * Ischial spine * Lesser Sciatic notch * Ischial tuberosity (part we sit on) * Obturator Foramen (posterior half)
Pelvic Girdle: Pubis * Anterior, inferior part of hip bone * Pubic Arch- formed by right and left pubis bones at pubic symphasis
False and True Pelves * Pelvic brim is oval ridge that runs from sacral promonotory, to the arcuate lines, to the superior region of the pubic symphsis * False Pelvis * Superior to pelvic brim
Females have more of a true pelvis
Male and Female Pelves * Male * Larger * Heavier * Narrower * Female * Wide * Shallow * More space in true pelvis * Accommodate pregnancy and childbirth Lower Limb * Consists of the following regions (number of individual bones) * Thigh (1) * Kneecap (1) * Leg (2)
Lower Limb: Femur * Longest and heaviest bone in body * Major Landmarks * Body (Shaft) * Head * Neck * Greater Trochanter (beside of the head) * Trochanters are only specific to femur * Lesser Trochanter * Medial and lateral condyles * Medial and lateral epicondyles

Lower Limb: Tibia and Fibula * Tibia is medial, Fibula is lateral * Tibia is much larger than Fibula * Fibula does no weight bearing * Landmarks: * Tibia (shin bone): * Medial condyle * Lateral condyle * Tibial tuberosity (need to know tendon that attaches there) * Medial malleolus * Fibular notch * Fibula: * Head * Lateral Malleolus
Lower Limb: Tarsals, Metatarsals, and Phalanges * Tarsus includes 7 Tarsal Bones * Talus- most superior and only one that articulates with tibia and fibula * Calcaneus- largest and strongest; heal bone * Metatarsals * Five intermediate foot bones * Phalanges * Three bones per toe, except two in big toe

Joints Intro * An articulation, or joint, is the area where two or more bones meet. * Classified as structural and functional
Structural Classification of joints * Based on the anatomical characteristics * Presence or absence of a synovial cavity * Type of connective tissue binding the bones together * Three structural types * Cartilaginous * Synovial * Fibrous
Fibrous joints * Dense connective tissue that holds them together, no movement
Cartilaginous joints * Have cartilage in them, does not always have synovial fluid, limited movement
Synovial joints * Most movable joints, and most complex * Articular hyaline cartilage lines them * Synovial fluid * Ligaments and tendons * Bursae and tendon sheaths
Articular Capsule * Two layers enclose the synovial cavity like a sleeve, capsul
Synovial joint cavity * Fluid capsule
Accessory structures: Ligaments and articular menisci * Absorbs shock
Bursae and tendon sheaths * Bursae: Connective tissue sac lined by synovial membrane and filled with synovial fluid * Cushion * Tendon Sheaths: