Portage A and P Module 4

nasal bones

form the bridge of the nose

transverse processes

have transverse foramina for the passage of the vertebral arteries and vertebral veins

Dislocation of a joint

means that the bone is removed from its socket. Dislocation of the shoulder occurs when the head of the humerus is removed from the glenoid cavity in any direction

Trochanter, tuberosity, tubercle, crest, line, spine

processes or projections for tendon or ligament attachment

acromion process

projects from the scapular spine, which can be seen from both the posterior and anterior views (Figure 4.23). The acromion process connects to the clavicle anteriorly

cranium function

protects the brains and is composed of eight bones fitted tightly together in adults

temporal bone

Below the much larger parietal bones, each temporal bone has an opening that leads to the middle ear

two main divisions of the skeleton

the axial skeleton and the appendicular skeleton

The humerus is comprised of

the head, neck, shaft, capitulum and trochlea

Mastoiditis

a condition that can lead to deafness, is an inflammation of the mastoid sinuses

ethmoid bone

which lies in front of the sphenoid, is a part of the orbital wall and, in addition, is a component of the nasal septum. The sphenoid and the ethmoid bones lie largely inside the skull

The lateral epicondyle of the humerus

can be palpated on the lateral side of the arm at the elbow

The medial epicondyle of the humerus

can be palpated on the medial side of the arm at the elbow

frontal bone

(one bone) forms the forehead, On the top of the cranium

Flat bones

(such as in the cranium) form the roof of the skull to protect the brain

parietal bones

(two, paired bones) extend to the sides

carpal bones

8, which look like small pebbles. The proximal row of carpal bones (from lateral to medial) are: scaphoid, lunate, triquetral, and pisiform. The distal row of carpal bones (from lateral to medial) are: trapezium, trapezoid, capitate, and hamate

Bone functions

All bones are storage areas for inorganic calcium and phosphorus salts. Bones also provide sites for attachment of muscle, tendons and ligaments. The long bones, particularly those of the legs and the arms, permit flexible body movement. The large, heavy bones of the legs support the body against the pull of gravity

ribs

All twelve pairs connect directly to the thoracic vertebrae posteriorly Ribs 1-7 connect directly to the sternum. Ribs 8-10 connect to the sternum indirectly via shafts of cartilage to the sternum. The lower two pairs of ribs (ribs 11 and 12) are called "floating ribs" because they do not attach to the sternum

Phalanges

Beyond the metacarpals, the bones of the fingers and the thumb. The phalanges of the hand are long, slender, and lightweight. The thumb, or first digit, is composed of two phalanges, while all other digits have three

bone landmarks

Bones are not simply smooth surfaces. Each bone has distinct markings, ridges, grooves or holes, called. Bone landmarks serve several functions. Some bone landmarks allow for tendons to attach. Other markings indicate where nerves and blood vessels run alongside the bone or penetrate the bone to provide blood and nervous supply

fontanelles

In newborns, certain bones are not completely formed and instead are joined by membranous regions called commonly called "soft spots". Fontanelles allow the bones of the skull to compress during childbirth and expand to accommodate a rapidly growing infant brain. These regions begin to close around two months but may last up to two years

Head, neck, condyle, trochlea, facet

Processes designed for articulation with adjacent bones

the humerus

The single long bone in the upper arm, has a smoothly rounded head (Figure 4.25) that fits into a socket of the scapula at the glenoid cavity (Figure 4.23). The glenoid cavity is very shallow and much smaller than the head of the humerus. The humerus needs to be held to the shallow glenoid cavity by the rotator cuff muscles and other ligaments. The structure of the shoulder permits movement of the arm in almost any direction but provides little stability. The gleno-humeral joint is prone to dislocation because it is held in place primarily by muscular and ligament attachment with very little bony stability

Number of facial bones and names

There are fourteen facial bones, mandible, vomer (nonpaired), maxillae, zygomatic, nasal, palatine, lacrimal, inferior, middle, and superior nasal conchae

cervical vertebra

There are seven cervical vertebrae. Each has a long spinous process with a bifid tip that splits into two parts posteriorly (except for C1). The cervical vertebral bodies are small, and the vertebral foramen are large

articular facets

allow adjacent vertebrae to articulate with each other. Note how the spinal cord is protected in the center of the vertebrae, and the spinal nerves exit in between the vertebrae

foramen magnum

allows for passage of the spinal cord into the skull

The pectoral girdle

also known as the shoulder girdle, is composed of two clavicles and two scapulae. Each clavicle (collarbone) connects with the sternum anteriorly and the scapula (shoulder blade) posteriorly

inferior nasal conchae

are bones located inferiorly to the middle conchae

middle and superior nasal conchae

are formed from the grooves of the ethmoid bone. The nasal conchae act to swirl the air as it is breathed in through the nasal passages, helping to warm and humidify the air before it enters the lower respiratory system

spinous processes

are located on the dorsal side of the vertebrae and can be palpated (examined externally by touch) as bony projections along the midline of the neck and back

Long bones

are long and thin, designed to support body weight and enable movement. Examples of long bones include the humerus, ulna, radius, tibia, fibula, metacarpals and metatarsals

Short bones

are small and cube-shaped. The carpals in the hand and the tarsals in the foot are short bones

Irregular bones

are varied in structure with ridges or irregular surfaces. The vertebrae are irregular bones designed to protect the spinal cord as well as enable spinal movements. The pelvic bones (ilium, ischium, and pubis) are also irregular bones

The capitulum of the humerus

articulates with a small portion of the radius

The trochlea of the humerus

articulates with the ulna

The groups names of vertebrae (anatomical regions) of the vertebrae are

cervical (neck), thoracic (back, ribs), lumbar (lower back), sacrum and coccyx (tail). When the vertebrae join, they form a canal (vertebral foramen) through which the spinal cord passes

Skeleton functions

comprised of a network of bones held together at joints, has many functions. The skeleton protects vital internal organs. For example, the skull forms a protective encasement for the brain. The rib cage provides protection for the heart and the lungs. Flat bones, such as those of the skull, the ribs, and the breastbone produce blood cells

sinuses

contained in the bones of the cranium, air spaces lined by mucous membrane Sinuses reduce the weight of the skull and give a resonant sound to the voice. Two sinuses called the mastoid sinuses drain into the middle ear

occipital bone

contains a large opening, the foramen magnum, through which the spinal cord passes to become the brain stem

The posterior side of the scapula

contains the supraspinatus fossa, infraspinatus fossa, and the scapular spine

occipital bone

curves to form the base of the skull

Fossa, sulcus

depressions in bone

five types of bones

each with a distinct shape and form (see Figure 4.1). The shape of a bone determines its function. Long bones, flat bones, short bones, irregular bones, sesamoid bones

Process, ramus

elevations in bone

vertebral column

extends from the skull to the pelvis. In a typical spine, the vertebral column has four curvatures that provide more resilience and strength in an upright posture than a straight column could. The various vertebrae are named according to their location in the vertebral column

metacarpal bones

fan out From the carpal bones to form a framework for the palm 5 The first metacarpal is the thumb, and the fifth metacarpal is the pinky. The metacarpal bone that leads to the thumb is placed in such a way that the thumb can reach out and touch the other digits. (Digits is a term that refers to either fingers or toes.

zygomatic bones

give us our cheekbone prominences

thoracic vertebra

has a long, thin spinous process that does not split The spinous process points inferiorly. The vertebral bodies are medium-sized and contain facets for rib articulations. The transverse processes also have costal facets for rib articulations. There are twelve thoracic vertebrae, all of which contain the facets for rib articulations except for T11 and T12

lumbar vertebra

has a shorter spinous process that is broader and points posteriorly. The vertebral bodies of the lumbar spine are the largest, enabling the it to support the weight of the head, neck, trunk, and upper limbs. The transverse processes are shorter and have no costal facets. The vertebral foramen of the lumbar spine are the smallest and triangular-shaped

bones of the cranium

have the same names as the lobes of the brain: frontal, parietal, temporal, and occipital

Sinus

hollow chamber in bone, usually filled with air

carotid canal

is an opening of the temporal bone for the internal carotid artery

sacrum

is comprised of five fused bones at the base of the spine The base of the sacrum is the widest portion which articulates with the L5 vertebra above it

coccyx

is comprised of four to five fused vertebrae, which typically begin to fuse by around age 25. The sacrum and coccyx provide attachment sites for many ligaments and tendons. The stability of the sacrum, coccyx and the ligaments anchoring them to the pelvis are key for pelvic stability

external acoustic meatus

is for transmission of sound, also located within the temporal bone

Bones of the skull

is formed by 22 bones: the cranium (8 bones) and the facial bones (14 bones)

The scapula

is freely movable and held in place only by muscles and ligaments. The attachment of the scapula allows it to follow the many movements of the arm

vertebral body

is located on the anterior portion and is the part of the vertebrae with the most surface area

The olecranon process of the ulna

is the prominent bone that can be palpated in the elbow posteriorly (Figure 4.26). When the arm is held in anatomical position (so that the palm is turned anteriorly), the radius and ulna are almost parallel to one another. When the arm is turned so that the palm is next to the body the radius crosses in front of the ulna, a feature that contributes to the easy twisting motion of the forearm (pronation)

axial skeleton

lies on the midline of the body and consists of the skull, the vertebral column, the sternum, laryngeal skeleton, and the thoracic (rib) cage

palatine bones

make up the posterior portion of the hard palate and the floor of the nasal cavity

sphenoid bone

not only completes the sides of the skull, it also contributes to the floors and walls of the eye sockets

foramina

of the skull allow for many functions, such as passage for blood vessels, nerves and the spinal cord

The neck of the scapula

on the lateral side contains the glenoid cavity, where the head of the humerus articulates with the scapula. The anterior side of the scapula contains the subscapular fossa. coracoid process: projects anteriorly from the scapula, allowing for muscular attachment

Foramen, canal, fissure

openings in bone to allow for nerves, blood supply or a passageway

sinusitis

sinus infection, occurs when the soft tissues inside the sinuses become inflamed from a virus, bacteria or allergen

mandible

the lower jaw, is the only movable portion of the skull

is comprised of three parts

the manubrium, body and xiphoid process. The appendicular skeleton: consists of the bones within the pectoral and pelvic girdles and the attached limbs. The pectoral (shoulder) girdle and upper limbs (arms) are specialized for flexibility and increased range of motion, while the pelvic girdle and lower limbs are specialized for strength

The distal end of the humerus meets the two bones of the lower arm

the ulna and the radius, at the elbow

maxillae

the upper jaw, forms the anterior portion of the hard palate and contains the infraorbital foramen. Tooth sockets are found in both the mandible and the maxillae

vomer

thin, flat joins with the perpendicular plate of the ethmoid to form the nasal septum

lacrimal bone

thin, scale-like lies between an ethmoid bone and a maxillary bone