Osteology

Bone

is a living tissue capable of changing its structure as the result of the stresses to which it is subjected.

protective function

Bone has a _____; the skull and vertebral column, for example, protect the brain and spinal cord from injury; the sternum and ribs protect the thoracic and upper abdominal viscera.

Framework

\- giving support to the softer tissues of the body

Attachment

\-muscles, tendons and ligaments

Protection

\- forming boxes or cages wherein delicate organs are lodged.

Locomotion

\- acting as passive levers during movement.

Blood cell formation

\- by producing red blood cells from contained red marrow.

calcium and phosphorus

Bone is a depository for

Compact and cancellous

Bone exists in two forms:

Compact bone

appears as a solid, dense mass.

cancellous or Spongy

bone consists of a branching network of trabeculae.

trabeculae

are arranged in such a manner as to resist the stresses and strains to which the bone is exposed.

Red marrow

fill up the spaces in the fresh state.

Long bones

are found in the limbs (e.g., the humerus, femur, metacarpals, metatarsals, and phalanges). Their length is greater than their breadth.

diaphysis

Long bones have a tubular shaft called the

epiphysis

Long bones usually have a ____ at each ends.

epiphyseal cartilage

During the growing phase, the diaphysis is separated from the epiphysis by an

metaphysis

The part of the diaphysis that lies adjacent to the epiphyseal cartilage is called the

bone marrow

The shaft has a central marrow cavity containing _____

periosteum

The outer part of the shaft is composed of compact bone that is covered by a connective tissue sheath, called the

hyaline cartilage

The articular surfaces of the ends of the bones are covered by?

Ends

Which part of long bones are composed of cancellous bone surrounded by a thin layer of compact bone.

Short bones

are found in the hand and foot. They are roughly cuboidal in shape and are composed of cancellous bone surrounded by a thin layer of compact bone.

Flat Bones

are found in the vault of the skull (e.g., the frontal and parietal bones). They are composed of thin inner and outer layers of compact bone, the tables, separated by a layer of cancellous bone, the diploë. The scapulae, although irregular, are included in this group.

Irregular bones

include those not assigned to the previous groups (e.g., the bones of the skull, the vertebrae, and the AC pelvic bones). They are composed of a thin shell of compact bone with an interior made up of cancellous bone.

Sesamoid Bones

are small nodules of bone that are found in certain tendons where they rub over bony surfaces.

greater part

Which part of a sesamoid bone is buried in the tendon?

reduce friction on the tendon

What is the function of a sesamoid bone?

Aditus

\- entrance into a cavity

Ala

\- wing-shaped projection or surface

Alveolus

\- deep, narrow pit

Antrum

\-cavity lines by mucous membrane filled with air

Canal

—passageway with complete walls surrounding it

Capitulum

\-head-like rounded prominence

Condyle

\- smooth, rounded enlargement whose articular surface is covered with cartilage

Cornu

\- horn-like projection

Crest

\- sharp, prominent, linear bony elevation

Epicondyle

\- smaller projection situated above a smooth articular eminence

Foramen

\- hole or opening.

Fossa

– shallow depression

Groove

\- a longitudinal depression

Hamulus

\- Hook-like projection

Hiatus

\- slit-like opening or gap

Labium

\- margin or rim of a groove.

Lamina

\-lamella- thin sheet of bone

Lingula

\- tongue like projection

Linea

long narrow elevation

Meatus

= passage or narrow short canal

Process

\- any marked projection

Ridge

\-Slightly prominent than a line

Spina or spine

\- sharp, slender projection

Squama

\- scale-like portion of a bone

Styloid

\- a more pronounced spine

Sulcus

\- a groove

Trochlea

\- a pulley-shaped surface

Tubercle

\- a rough eminence

Tuberosity

\- a larger and rougher elevation

Uncus

\- a projection shaped like a hook.

Vertebral Column

Flexible central pillar of the body

32

How many vertebrae

True/ movable

– cervical, thoracic, and lumbar regions which are separated throughout life.

False/fixed

– sacral and coccygeal regions which in the adult fuse into the sacrum and coccyx respectively.

Intervertebral disc

The flatted plates of fibro-cartilages that are interposed between the adjacent surfaces of the bodies of the vertebrae. Thickest in the cervical and lumbar regions.

Body or Centrum

–the larger anterior part

Vertebral or neural arch

\- the posterior curved part.

Pedicles or roots

\-two short, thick processes by which the arch is attached to the upper part of the surface of the body.

Vertebral notches

\- the concavities on the superior and inferior surface of the pedicles.

Intervertebral Foramen

The rounded hole produced by the notches when two contiguous vertebra are articulated.

Laminae

\- two broad plates that make up the greater part of the vertebral arch.

Vertebral Foramen

\- the large opening bounded by the body anteriorly, and by the arch laterally and posteriorly

Spinous Process

the median projection that is directed backwards and downwards from the union of the laminae

Articular Processes

two superior and inferior projections from the junctions of the pedicles and laminae.

Transverse Processes

two projections directed laterally from the junction of the pedicles and laminae.

Cervical Vertebrae

7, smallest of the true vertebrae

Anterior Arch

narrow anterior portion of the ring

Fovea Dentis

\- smooth articular surface on the posterior surface of the anterior arch.

Posterior arch

\- twice the length of the anterior arch

Anterior tubercle

\- smooth eminence on the middle of the anterior surface of the anterior arch.

Posterior tubercle

\- small eminence that represents the spinous process.

Axis (C2)

strongest. Thickest. (vertebra)

Odontoid process/Dens

\- tooth-like projection on the superior surface of the body.

vertebral promenins (c7)

\- long and prominent spinous process, non bifid and ends in a broad tubercle.

12

How many Thoracic vertebrae

Laminae

\- narrow and directed downwards. Overlapping the lamina below.

Vertebral Foramen

\- smaller than cervical and lumbar

Lumbar Vertebrae

5, the largest of the movable vertebrae.

Spinous processes of Lumbar

large, hatchet-shaped and horizontally placed

Mamillary Process

\- smooth rounded eminences projecting from the posterior parts of the superior articular processes.

Sacrum

Large triangular bone, represents the five sacral vertebrae which in adult fused.

Anterior surface or pelvis surface

concave smooth looks downward and forward.

Transverse Ridges

four horizontal lines that indicates the ossified intervertebral disks. Line of fusion of the 5 vertebrae

Anterior sacral foramina

\- a pair of holes on each end of the transverse ridges.

Promontory

– the prominent anterior border of the upper surface of the first sacral vertebrae.

Alae

– The upper surfaces of the lateral masses, spreading laterally.

Auricular surface

\- the well-defined smooth area laterally, articulates with the Hip Bone.

Median Crest

uneven ridge along the median line, representing the fused spinous processes.

Sacral Groove

\- the shallow concavity on either side of the median crest, representing the fused laminae of the sacral vertebrae

Sacral Tuberosity

the rough uneven area posterior to the auricular surface.

Sacral cornu

blunt projections at the inferior ends of the articular sacral crest, corresponding to the inferior articular processes of the fifth sacral vertebrae.

Hiatus sacralis

space or interval between the two sacral cornu