Download Bones of the Skeleton

Unit 4 Lab: Bones of the Skeleton
(adapted from activities created by A.Tomada and P. Carothers)
Learning Objectives –
When you finish these exercises you should be able to:
1. Identify the main bones that form the axial and appendicular skeleton
2. Compare and contrast skeletal structure in fetal and adult skeletons
3. Identify distinguishing bone markings in different types of bones
4. distinguish between cranial bones and facial bones of the skull
5. identify all the bones of the skull and their important markings in a specimen or diagrammed figure.
6. Identify the types and structure-function-location correlation of different vertebrae
7. Identify the different types of bones that form the upper and lower extremities
You will be working on a series of identification activities. Use your application packet to indicate the
regions you identify, and to make notes on as needed.
Activity #1 - The Plan of the skeleton
The usual number given for bones in the human skeleton is 206. This is not an absolute exact number. Most
people have more bones, but each person has different types, locations and numbers of “extra” bones.
The standard axial skeleton consists of 80 bones that form the central axis of the skeleton. These 80 bones
include the 28 skull bones, 1 unattached hyoid bone in the throat area, 26 vertebrae, 24 rib bones.
The appendicular skeleton includes the appendages composed of 126 non-axial bones of the upper and lower
extremities.
Table Bones of the Skeleton 206 *excluding variable sesamoid and wormian bones
Part of body
Name of bone
Skull 28 bones total
Cranium (8 bones)
Frontal
Parietal -2
Temporal -2
Occipital
Sphenoid
Ethmoid
Face
Nasal -2
Maxillary-2
Zygomatic (malar) -2
Mandible
Lacrimal-2
PalatineInferior conchae/turbinates -2
Vomer
Ear bones
Malleus (hammer) -2
Incus (anvil) -2
Stapes (stirrup)-2
Hyoid
Hyoid -1
Spinal Column 26
bones total
Cervical vertebrae -7
Thoracic vertebrae -12
Lumbar vertebrae -5
Sacrum -1
Coccyx -1
Sternum & Ribs 25
bones total
Sternum -1
True ribs -14
False ribs -10 (4 of which are often referred to as floating)
Upper Extremities
(including shoulder
girdle) 64 bones
total
Lower extremities
(62 bones total)
Clavicle -2
Scapla-2
Humerus-2
Radius-2
Ulna-2
Carpals-16
Metacarpals-10
Phalanges-28
Coxal bones -2
Femur-2
Patella-2
Tibia-2
Tibia-2
Fibula-2
Tasrals-14
Metatarsals-10
Phalanges-28
1. Study the articulated human skeletons to identify the 206 bones in the table. Look for any
missing or extra bones. Label the skeleton diagram (page 9) in your application packet and
make notes along the margins.
Activity #2 – Fetal Skeleton
2. Look at the image of a fetal skeleton below. Identify differences between adult and fetal skeletons.
Activity #3 – The Skull
The skull is the superior portion of the axial skeleton. For ease of study, the 28 bones of the skull are divided
into three categories. The cranial bones form a roughly spherical case for the brain called the cranium. The
facial bones include most of the remaining skull bones, except the six auditory ossicles of the middle ear. In
this exercise, all 28 skull bones are presented for study.
Special Precautions: Please read before proceeding.
Because most of the skulls you are working with are from human donors you are to be respectful and careful in
handling them. The human bones we use in lab are irreplaceable if damaged because human remains are no
longer for sale through the various biological supply catalogues. Therefore, that being said, they truly are
PRICELESS. At all times when the skulls are removed from the plastic container, they are to be held between
two hands and OVER the hand towel which is there in the event the skull slips out of ones hands it would
hopefully fall a short distance onto the towel and avoid hitting the floor or the hard lab table top. The
demonstration pointer is used instead of a pen or pencil to study the features of the skull to avoid marking on
or damage to its delicate parts.
Procedure: Locate each of the parts listed that are typed in bold. Complete page 11 in packet.
Part A. Bones of the Cranium
1. Eight of the 28 bones form the cranium of the skull. Locate, in a specimen and in a figure, each bone
and marking listed, noting the distinguishing characteristics of each. As with all bones and markings
studied in this course, try to understand the structural and functional relationships with surrounding
structures
2. The single FRONTAL BONE forms the anterior third of the cranial dome. Locate these 2 features on
your specimens frontal bone:
*supraorbital foramen – hole on the superior edge of the orbit and
*frontal sinus (seen with removal of the top of the cranial dome or in the 1/ 2 skull only) – air space on the
midline, between and superior to the orbits for the eyes.
3. The left and right PARIETAL BONES form the middle segment of the cranial dome, joined with other
cranial bones to form these sutures.
*sagittal suture - Joins the two parietal bones
*coronal suture – joins the frontal bone to the parietal bones
*lambdoidal suture – joins the parietal bones with the occipital bone
4. The SPHENOID bone is a bat & butterfly-shaped bone that forms part of the anterior floor and sides of
the cranium. The *body is the hollow, cube-like central portion. Locate the sphenoid in the
articulated skull and also study the disarticulated specimen at lab table #8. Locate these
features of the Sphenoid:
*Greater wings – lateral, winglike extensions of the body that form part of the lateral wall of the orbit (eye
socket) wall. This portion is more butterfly-like.
*Lesser wings – narrow, bat wing-like extension of the upper part of the body that form the posterior part of
the orbit’s roof.
*Optic foramen – Round hole (for the optic nerve) through the back of the wall of the orbit
*Superior orbital fissure – Crack like opening lateral to the optic foramen
*Inferior orbital fissure – crack like opening in the inferior back wall of the orbit
*Foramen rotundum – round opening seen from the inside of the skull, anterior to the foramen ovale. The
maxillary branch of cranial nerve V exits the brain through this hole.
*Foramen ovale – Oval opening seen from the inside of the skull, posterior to the foramen rotundum. The
mandibular branch of cranial nerve V exits the brain through this hole.
*Foramen spinosum – Small opening, often with a small, spinelike bump protruding into in, posterior to
foramen ovale. The middle meningeal artery which serves the internal faces of some of the cranial bones
travels through this hole.
*Sella Turcica – Literally “Turkish saddle,” a double projection on the superior aspect of the sphenoid. This
forms a depression that houses and protects the pituitary gland as it hangs off of the inferior aspect of the
brain.
*Sphenoid sinus – Air space inferior to the sella turcica, within the body of the sphenoid bone (seen in the ½
skull only)
5. The paired TEMPORAL bones are at the sides of the cranium, extending inward to form part of the cranial
floor. Locate the Temporal bone in the articulated skull and also study the disarticulated specimen at
lab table #8. Find these temporal bone structures:
* Zygomatic process – narrow, bridge like projection of the temporal bone; articulates with the temporal
process of the zygomatic bone together they form the zygomatic arch.
*Mastoid process – large bump posterior and inferior to the external auditory meatus. You can easily find this
process on your own head if you palpate the area behind the inferior curve of your own ear. It is one of the
anchoring sites of the sternocleidomastoid muscle that moves the head.
*Styloid process – Thin needle like process anterior to the mastoid process…in human skull specimens it is
unfortunately often broken by rough handling and often only the stump of this bone is seen. It serves as the
attachment point for several tongue and neck muscles and also attaches the ligament that secures the hyoid
bone of the neck to the skull.
*External auditory/acoustic meatus – Tube like opening of the ear canal. Sound is carried through this canal
to the eardrum.
*Petrous portion – Can only be seen from the inside of the skull; looks like a “rocky cliff” anterior to the
occipital bone which it connects to posteriorly.
*Squamosal suture – Joint along the top, curved edge of the temporal bone
*Mandibular fossa – Depression that receives the condyle of the mandible
*Temporomandibular joint (TMJ) – Joint formed by the mandibular fossa and the mandibular condyle so the
lower jaw bone, the mandible can move.
*Internal auditory meatus – tube like opening in the petrous portion
*Jugular foramen – Round hole at the junction of the petrous portion and the occipital bone.
*Carotid foramen – Canal through the petrous portion, slightly medial to the jugular foramen.
*Stylomastoid foramen – Hole between the styloid and mastoid processes, allowing cranial nerve VII (the
facial nerve) to leave the skull.
6. The OCCIPITAL BONE forms the posterior portion of the cranial dome, curving inferiorly to the base of the
cranium. Locate the occipital bone in the articulated skull and also study the disarticulated specimen
at lab table #8. Locate these important features:
*Foramen magnum – very large hole for the spinal cord.
*Occipital condyle – flattened bmp lateral to the foramen magnum.
7. The ETHMOID BONE is a delicate structure that forms the middle portion of the anterior cranial floor,
extending inferiorly between the eye orbits to also form the roof of the nasal cavity. Locate the ethmoid bone
in the articulated skull and also study the disarticulated specimen. Find these important ethmoid
structures:
*Ethmoid sinuses (air cells) – air spaces within the main portion of the bone
*Perpendicular plate – thin plate projecting downward along the midsagittal plane, it forms the upper nasal
septum which divides the left and right nasal cavities. Unfortunately the perpendicular plate is often broken by
rough handling, allowing one to only view the upper most section.
*Crista galli – Literally “cock’s comb,” it is a crest on the superior midline of the ethmoid bone that resembles a
rooster’s comb. It attaches to the outmost covering of the brain, the Dura Mater, to secure the brain in the
cranial cavity.
*Middle nasal concha (turbinate) – curved projections from the nasal cavity’s lateral wall.
*Cribiriform plate – thin perforated plate forming the ethmoid’s superor surface. (Cribr = sieve) Unfortunately
due to rough handling the cribiriform plate is often broken.
*Olfactory foramina – tiny holes in the cribriform plate (for olfactory nerves receptors to pass through and
enter the upper nasal cavity). Unfortunately due to rough handling the olfactory foramina are often broken
Part B. Bones of the Face.
1. The two MAXILLAE, or MAXILLARY BONES, are also called the upper jawbones. They support the
face from the eyes down to the mouth, across the front of the cheek. All facial bones except the
mandible articulate with the maxillae, hence, the maxillae are considered the keystone bones of the
facial skeleton. Locate the maxillae in the articulated skull and also study the disarticulated
specimen. Locate these maxillary features:
*Palatine process – plate like posterior projection of the upper jaw; forms the anterior part of the hard palate
*Incisive foramen – anterior hole in the palatine process near the body’s midline. It serves as a passageway
for blood vessels and nerves
*alveolar process – ridges in which the teeth of the upper jaw are anchored
*Infraorbital foramen – hole on the anterior “cheek,” below the orbit. Allows a branch off of the maxillary nerve
to reach the face.
*Maxillary sinus – air spaces within the maxilla’s “cheek” portion. Best seen in the ½ skull and the
disarticulated specimen.
*Anterior nasal spine – where the two maxillae meet.
2. Each of the two LACRIMAL BONES is on the medial margin of an eye orbit, between the ethmoid bone
and an upward projection of the maxilla. Each has a hole where a tear duct is located (in life). Unfortunately
due to rough handling the lacrimal bones are often broken
3. NASAL BONES (left and right) are joined at the midline forming the superior margin of the nasal opening.
4. The two PALATINE bones join together at the midline to form the posterior third of the hard palate (roof of
the mouth).
5. INFERIOR NASAL CONCHAE, or turbinate bones, are a pair of thin, curved bones. They project medially
from the lateral walls of the nasal cavity.
6. MANDIBLE, or lower jaw, is an oddly shaped bone forming the lower part of the face. It is the strongest
bone of the face. Locate the mandible in the articulated skull and also study the disarticulated
specimen. Locate these elements of the mandible:
*Ramus – the posterior arms of the mandible that angle upward. “rami” = branches.
*mandibular arch/notch – Large, U-shaped curve of the superior edge of the ramus
* mandibular condyle – rounded, posterior of two projections on the superior part of the ramus. The condyle
articulates with the mandibular fossa of the temporal bone forming the TMJ.
*coronoid process – anterior of two superior projections of the ramus. It is pointed and “crown shaped”. It is
an insertion point for the large temporalis muscle that raises the jaw when chewing.
*Angle – the corner formed where the ramus begins its upward angle
*Body – the entire anterior portion of the mandible which forms the chin to which the rami are attached.
*Mandibular foramen – hole on the inside surface of the ramus, near the angle which permit the nerves
responsible for tooth sensation to pass to the teeth in the lower jaw.
*Mental foramen – hole on the outside surface of the body, just lateral to the midline. The hole allows blood
vessels and nerves to pass to the skin of the chin and lower lip. “ment” = chin.
7. ZYGOMATIC BONES form the upper lateral corner of a cheek, from the lower eye orbit around to the
temporal bone. Locate:
*temporal process – wedge-shaped process that joins the zygomatic process of the temporal bone
*zygomatic arch – complete bridge-like structure formed by the zygomatic process of the temporal bone and
the temporal process of the zygomatic bone.
8. VOMER – The bone forms the lower portion of the nasal septum that divides the nasal cavity.
Part C. Orbit of the Eye
Seven bones form the orbit of the eye that houses the eyeball: frontal, sphenoid, lacrimal, zygomatic, greater
wing of sphenoid, lesser wing of sphenoid, maxilla. . Examine the orbit of the eye to identify the bones that
contribute to its structure:
Lateral wall of orbit = zygomatic process of the frontal bone, greater wing of the sphenoid, zygomatic bone
Floor of orbit = palatine bone, maxillary bone, zygomatic bone
Medial wall = sphenoid body, ethmoid bone, maxilla, lacrimal bone
Roof of orbit = lesser wing of sphenoid, frontal bone
Part D. Auditory ossicles
Each middle ear, within the petrous portion of the temporal bone, contains three auditory
ossicles. The ossicles transmit the vibratory motion of the eardrum to the oval window, which in turns sets the
fluids of the internal ear into motion, eventually exciting he hearing receptors. They can only be viewed as
disarticulated bones.
*Malleus is also called the hammer.
*Incus is also called the anvil
*Stapes is known as the stirrup
Part E. The Fetal Skull
The fetal skull features partly ossified skull bones and a large proportion of fibrous and cartilaginous
tissue. Because the flat bones of the cranium have not met to form sutures, there are six fibrous areas called
fontanels. Complete page 10 in application packet.
*anterolateral, or sphenoid fontanels – there are 2 of these located at the junction of the sphenoid,
temporal, parietal, and frontal bones.
*posterolateral, or mastoid fontanels – there are 2 of these located at the junction of the temporal, parietal,
and occipital bones.
*anterior, or coronal fontanel – can be found where the right and left parietal bones are to meet the frontal
bone.
*posterior fontanel – forms where the parietal bones are to meet the occipital bone.
Activity #4 – Vertebral Column and Thoracic Cage
A. The vertebral column.
Complete pages 13-14 in the packet.
1. Find each bone and its important features on both an articulated skeleton and among the separate
bones of a disarticulated skeleton and/ vertebrae set.
2. The 7 cervical vertebrae at the superior end of the vertebral column are designated individually by
number. The most superior is C1, the next is C2, and so on. Of C1 through C7, only the first two have
commonly used alternate names:
a. atlas = C1 is a ringlike vertebra that supports the skull by forming a joint with the occipital
condyles. The atlas has an anterior arch and posterior arch fused to left and right lateral masses
to form a circle. Flat articulating facets are found on both the superior and inferior aspects.
b. axis = C2 is remarkable for its dens or odontoid (toothlike) process. The dens points superiorly
through the atlas to act as a pivot for the rotation of C1 and the skull. In an articulated skeleton or
figure, notice the cervical curve of the vertebral column produced by these seven vertebrae. This
curve is considered to be a secondary curve. Consider how this curve is created.
3. The 12 Thoracic vertebrae (T1-T12) are inferior to the cervical vertebrae. As a group, they cure in the
opposite direction of the cervical curve to form the thoracic curve which is considered to be a primary
curve. Consider how this curve is created (see lecture notes).
4. Five large lumbar vertebrae (L1-L5) form the curve of the lower back, or lumbar curve. The lumbar
curve is considered to be a secondary curve. Consider how this curve is created.
ALL VERTEBRAE from C3-L5 have certain common features. Find each of these features on examples of
all three vertebral types (cervical, thoracic, lumbar) a. vertebral foramen – large hole (for the spinal cord) in the center
b. spinous process – spine projecting posteriorly (a bifid or forked, spinous process in cervical
vertebrae). Serves as attachment point for muscles of the back
c. body – thick disk of bone forming the anterior arch (also known as the centrum).
d. Lamina – thin plate like section forming each leg of the posterior arch
e. pedicle – lateral section joining the lamina to the body (like a bridge)
f. intervertebral foramen – hole formed between laminae of successive vertebrae (for spinal
nerves)
g. transverse process – spine that projects laterally. Serve as attachment points for ligaments
and tendons from muscles of he back.
h. superior articular facets – flat surfaces on the superior aspect. These form moveable joints
with the inferior articular facets
i. inferior articular facets – flat surfaces on the inferior aspect. These form moveable joints with
the superor articular facets
5. The sacrum is a bone that develops as a set of five vertebrae that fuse to form one large bone inferior
to L5. A slight sacral curve can be seen from the lateral perspective. In the female skeleton the sacral
curve is accentuated. . The sacral curve is considered to be a primary curve. Consider how this
curve is created (see lecture notes). Find these sacral features:
a. Dorsal foramina – double row of holes between fused segments that form the sacrum (dorsal
aspect)
b. Pelvic foramina – similar to dorsal foramina, but on the ventral aspect
c. Sacral canal – canal formed by the vertebral foramina of the fused sacral segments
d. Sacral hiatus – open space at the caudal end of the sacral canal (where the last two sacral
segments have incomplete spinous processes)
e. Median sacral crest – bumpy ridge formed by fusion of sacral spinous processes
f. Sacral promontory – jutting ventral lip of the superior sacral segment. The body’s center of gravity
lies about 1 cm posterior to this landmark. In a male skeleton, the sacral promontory is more ventral
6. The most inferior bone of the vertebral column is the coccyx, or tailbone. This bone, like the sacrum, is
actually a fusion of several vertebrae. In the female skeleton, the coccyx is more moveable and
straighter than in the male.
B. Hyoid Bone
1. The hyoid bone is not really part of the vertebral column but is considered here. This is a U-shaped bone in
the throat. It serves an attachment for tongue muscles and connective tissue associated with the larynx (voice
box). In most articulated skeletons it is suspended by a wire.
C. Special features of vertebra in addition to the common features of each vertebra type:
1. Cervical Vertebra:
a. Each of the cervical vertebrae have three holes instead of just one. In addition to the
intervertebral foramen, the cervical vertebrae have transverse foramina – hole in a transverse
process through which the vertebral arteries pass to service the brain.
b. C7 can be used as a landmark for counting the vertebrae and is called the vertebra prominens
because it’s spinous process is NOT bifid (forked) and is much larger than those of C1-6.
2. Thoracic Vertebra:
a. These typically have two demifacets (tiny half facets) on each side at the body. The
demifacets show where the heads of the ribs attach.
b. The transverse processes of the thoracic vertebrae have articular facets for the tubercle of
the rib to attach.
D.
The Thoracic Cage (ribs and sternum)
Complete page 12 in the packet.
1. The 25 bones of the rib cage, or thoracic cage, form a partially flexible, protective shield for the heart,
lungs and other thoracic organs. The thoracic cage also helps protect some organs of the upper
abdomen, such as the live and spleen. Locate the major structures of the thoracic cage:
a. Each of the 12 pairs of ribs articulates with the vertebral column in two places: 1) the head of the
rib and 2) the tubercle of the rib.
b. 14 of the ribs are called true ribs because they directly attach to the sternum by way of the costal
cartilages.
c. Inferior to the true ribs are the 5 pairs of false ribs which do not directly connect to the
sternum. The upper three pair of false ribs indirectly connect to the sternum via the costal
cartilages of true ribs. The last two pair of false ribs do not connect to the sternum in any way and
are called floating ribs
2. Identify these features of the ribs in the list below:
a. shaft – the bulk of a rib
b. head – the posterior end which articulates with the body of he vertebrae.
c. tubercle – lateral to the neck is a knoblike structure which articulates with the transverse
process of the thoracic vertebra.
d. neck – the constricted point on the rib between the head and the shaft.
e. costal end/cartilage – opposite end of the head of the rib.
f. You will be responsible for determining if the rib is a left or a right. (See reading or
lecture notes for these hints)
3. The Sternum (breast bone) receives the costal cartilages of the 14 true ribs on the anterior aspect of
the thoracic cage . In life it forms an anterior protective wall over the heart and associated
structures. Find these features of the sernum:
a. body (gladiolus) – main middle portion of the sternum
b. manubrium – superior segment
c. jugular (suprasternal) notch is the central indentation in the superior border of the manubrium. It
is the point where the left common carotid artery leaves the aorta.
d. clavicular notches located on the lateral superior portions of the manubrium.
e. xiphoid process – inferior, pointed segment. It is a plate of hyaline cartilage in youth but is
ossified in older individuals. It serves as an attachment point for some abdominal muscles.
Activity #5 – Upper Extremity
Part A. The Shoulder Girdle
Complete page 15 in the packet.
1) The scapula or shoulder blade, forms part of the shoulder girdle that supports the arms. It is an irregular
bone on the superior, posterior aspect of the rib cage that extends laterally to form a joint with the arm. Find
these features of the scapula:
a. axillary/lateral border – edge of the triangular scapula that faces the armpit region.
b. Vertebral/medial border – scapular edge that faces the vertebral column
c. Superior border – superior edge of the scapula
d. Acromion process - large process projecting laterally from the scapular spine to form part of the
shoulder joint
e. Coracoid process – process anterior to, but smaller than, the acromion process
f. Glenoid cavity (or fossa) – depression at the upper, lateral corner of the scapular triangle; it forms part
of the shoulder socket
g. Spine – large, dorsal crest extending from the vertebral border to the acromion process.
2) The clavicle, or collarbone, is the other bone of the shoulder girdle. The clavicle is a long bone whose long
axis lies along a horizontal axis on the anterior, superior aspect of the thoracic cage. Find these features of the
clavicle
a. acromial end – the lateral end that articulates with the acromion process of the scapula
b. sternal end – the medial end that articulates with the sternum
c. conoid tubercle – a small bump/projection on the inferior, posterior surface of the bone serving as an
attachment point for muscles.
Part B. The Arm and Forearm
Complete page 16-17 in the packet.
1) The humerus is the large, long bone of the upper arm. Find these parts:
a. head – enlarged proximal portion that fits into the glenoid cavity of the scapula
b. anatomical neck – diagonal line just inferior to the articular surface of the head
c. surgical neck – the point at which the bone narrows significantly distal to the head. Named thus because it
is the most frequently fractured part of the humerus.
d. Greater tubercle – large bump near the lateral aspect of the head. It is an attachment point for rotator cuff
muscles.
e. lesser tubercle – bump near the midline of the head’s anterior aspect. It is an attachment point for rotator
cuff muscles.
f. intertubercular sulcus – groove between the greater and lesser tubercles. Acts as a guide for the tendon of
the biceps muscle.
g. deltoid tuberosity – rough deltoid muscle attachment site near the middle of the lateral surface of the shaft of
the humerus.
h. coronoid fossa – depression on the anterior, distal surface that articulates with the ulna’s coronoid process.
i. olecranon fossa – deep depression on the posterior, distal surface that articulates with the ulna’s olecranon
process forming part of the elbow joint.
j. radial fossa- depression lateral to the coronoid fossa, receives head of radius.
k. trochlea – spool shaped (hour glass shaped) articulating surface on the distal end that articulates with the
ulna’s trochlear notch.
l. capitulum – ball like articulating surface on the distal end; lateral to the trochlea, that articulates with the head
of the radius.
m. medial epicondyle – blunt projection of bone on the medial aspect of the distal end. Serves as a muscle
attachment point
n. lateral epicondyle – blunt projection of bone on the lateral aspect of the distal end. Also serving as a muscle
attachment point.
2) The radius is one of two long bones of the lower arm. When it rotates, the hand rotates. It is a major
forearm bone contributing to the wrist joint action. It is lateral to the other lower arm bone (when in the
anatomical position), and articulates with the capitulum’s of the humerus. Find these features:
a. head – proximal disk like enlargement that articulates with the trochlea
b. radial tuberosity – oval bump just distal to the head on the medial surface (facing the ulna). This anchors
the bicep muscle to the arm
c. styloid process – pointed bump on the lateral aspect of the distal end (in anatomical position). It anchors
ligaments that run to the wrist.
d. ulnar notch – medial side of the distal end of radius (in anatomical position) it articulates with the ulna.
3) The ulna, the other long bone of the lower arm; articulates with the trochlea of the humerus. Find these
markings of the ulna:
a. olecrannon process – large proximal process that forms the blunt point on the posterior aspect of the flexed
elbow joint. “Student elbow = colcannon bursitis”
b. trochlear (semilunar) notch - curved anterior indentation on the colcannon that articulates with the trochlea
of the humerus
c. coronoid process – sharp, anterior lip of the trochlear notch that articulates with the coronoid fossa of the
humerus
d. head – distal enlargement
e. styloid process – pointed bump on the medial aspect of the head.
f. radial notch – on the lateral side of the coronoid process is a small depression, where the ulna articulates
with the head of the radius.
Part C. The Wrist and Hand
1) The carpus or the wrist is composed of 8 small cuboid bones. 4 bones in the proximal row and 4 bones in
the distal row. Mnemonics help us to learn them such as: distal row from medial to lateral = “Please tell Luke
Skywalker; proximal row lateral to medial “to take Chewy home”
a. pisiform – pea shaped medial in anatomic position
b. triquetral - (triangular)
c. lunate - half moon shaped
d. scaphoid - somewhat S-shaped or boat shaped
e. hamate - has a “hook” on it to resemble a hammer handle
f. capitate – head shaped (looks like Darth Vader head)
g. trapezoid – “little table” has a shelf
h. trapezium – four sided
2) The hand consists of 5 similar metacarpal bones, numbered 1-5 (starting from the thumb side) and make
up the palm. Articulating with these are the phalanges, or finger bones.
a. metacarpals 1-5
b. heads of metacarpals- hen you clench your fist, the heads of the metacarpals become prominent as your
knuckles.
3) The phalanges are also named 1-5. according to their position and make up the fingers.
a. proximal
b. middle (not present in thumb)
c. distal and numbered 1-5, according to their position.
Activity #5 - The Lower Extremities
Part A. The Pelvic Girdle
Complete page 15 in the packet.
1) The left and right coxal bones, or pelvic bones, join to form the pelvic girdle and articulate with the coxae to
support the legs. The coxae- is the fusion of three bones: the ilium, ishium and pubis.
a. acetabulum- cuplike socket where the ilium, ischium and pubis articulate with the head of the femur
b. ilium- lateral, superior region of the bone, includes the bowl-like wall of the upper pelvis
i. iliac fossa- concavity in the ala (wing)
ii. iliac crest- upper curving “lip” of the bowl
iii. anterior superior spines- blunt anterior points at the end of the iliac crest
iv. anterior inferior spines- smaller blunt points a short distance below the anterior superior spines
v. posterior superior spines- points at the posterior end of the iliac crest
vi. posterior inferior spines- points a short distance below the posterior superior spines
vii. pelvic brim- superior margin of the true pelvis (separates true and false pelvis)
a. true pelvis- space below the pelvic brim in which pelvic organs usually lie
b. false pelvis- broad, shallow space above the pelvic brim and below iliac crests, part of the abdomen
c. ischium- inferior, posterior, lateral coxal region
i. ischial spine- pointed process on the inferior edge of the ischial region that protrudes into the pelvic outlet
ii. ischial tuberosity- rough, thickened area on inferior surface (sit bones)
d. pubis- inferior medial region
i. obturator foramen- large hole formed by the curve of the pubis medially and the ischium
ii. pubic symphysis joint- joint between left and right pubis
iii. pubic arch- inferior to pubic symphysis- helps differentiate between males and females
iv. pelvic outlet- inferior margin of the true pelvis, bounded anteriorly by the pubic arch, laterally by the ischia,
and posteriorly by the sacrum and coccyx
Part B. The Thigh and Leg
Complete page 16-17 in the packet.
1) The femur is the solo bone of the thigh. It is the largest, longest, strongest bone in the body
a. head- large, spherical enlargement at proximal end
b. neck- narrow region just distal to the head
c. greater trochanter- large bump that forms a lateral, proximal “corner”
d. lesser trochanter- bump on medial, proximal aspect (just distal to the neck)
e. intertrochanteric line- line that runs between greater and lesser trochanter
f. linea aspera- ridge that runs lengthwise along posterior surface of shaft
g. gluteal tuberosity- distal to the greater trochanter, lateral line that becomes part of linea aspera
h. medial condyle- medial, distal bump that articulates with the tibia
i. medial epicondyle- blunt projection from the side of the medial condyle
i. lateral condyle- lateral, distal bump that articulates with the tibia
i. lateral epicondyle- blunt projection from the side of the lateral condyle
j. intercondylar fossa- U-shaped depression between condyles
2) The patella is a large sesamoid bone forming the anterior bone of the knee joint
3) The tibia, or “shinbone”, is one of two long bones of the lower leg. It is that larger, medial lower leg bone. It
is second only to the femur in size and strength.
a. lateral condyle- lateral, proximal articular surface
b. medial condyle- medial, proximal articular surface
c. intercondylar eminence- irregular projection between the condyles
c. crest (anterior border)- sharp ridge running longitudinally along the anterior surface
d. tibial tuberosity- rough bump on anterior aspect, just distal to the condyles
e. medial malleolus- pointed bump on the meidal aspect of the distal end
f. articular surface- distal portion, flat to articulate with talus bone of foot
4) The fibula is the narrower, lateral bone of the lower leg.
a. head- proximal enlargement
b. lateral malleolus- pointed bump on the lateral aspect of the distal end
Part C. Foot and Ankle
1) The seven tarsal bones form the ankle:
a. talus
b. calcaneus
c. cuboid
d. navicular
e. medial cuneiform
f. intermediate cuneiform
g. lateral cuneiform
2) The foot comprises of five metatarsal bones and 28 phalanges (just like the hand!)
a. metarasals 1-5
b. distal phalanges
c. middle phalanges
d. proximal phalanges