Skeletal System Study Guide

ZOO 200 SKELETAL SYSTEM STUDY GUIDE

To prepare for the skeletal system lab practical, be able to identify the following bones and other skeletal features. For the pelvic & pectoral girdles, arms & legs, and the hands & feet, be able to distinguish between right and left bones.

The number in parenthesis following the name of a bone or skeletal feature refers to the total number present in the body; e.g. we have 2 parietal bones and 1 frontal bone.

Surface anatomy: many of these bones and associated structures can be felt on your own body; such structures are indicated by the word “feel” immediately after their name; so feel!

There is a plastic, articulated skeleton on reserve in the library. Ask for it at the circulation desk, second floor.

THE AXIAL SKELETON

Bones and other features of the skull

Frontal (1)

frontal sinus

Parietals (R, L)

Temporals (R,L)

external acoustic meatus (feel)
petrous part
zygomatic process
mastoid process (feel)
mandibular fossa
styloid process
carotid canal
internal acoustic meatus

Occipital (1)

foramen magnum
hypoglossal canal
occipital condyles
jugular foramen (between the occipital and temporal bones).

Sphenoid (1)

greater and lesser wings
optic foramen (canal)
foramen ovale
foramen rotundum
lateral and medial plates of the pterygoid processes
sella turcica
superior orbital fissure

Ethmoid (1)

perpendicular plate
cribriform plate
crista galli
superior and middle nasal conchae (the conchae are also known as the turbinates.)

Inferior Nasal Conchae (R,L) (also known as the inferior nasal turbinates.)

Palatines (R,L)

Zygomatics (feel) (R,L)

temporal process [note the zygomatic arch (feel],formed by the temporal process of the zygomatic bone and the zygomatic process of the temporal bone)

Nasals (R, L) (feel)

Lacrimals (R,L)

Vomer (1)

Maxillae (R, L)

palatine processes
median palatine suture

Mandible (1)

body
ramus
condylar process
angle (feel)
coronoid process
mental foramen

Sutures of Skull

Coronal (1)
Sagittal (1)
Lambdoidal (1)
Squamosal (R,L)

Fontanels of Fetal and Newborn Skull

Anterior (frontal) (1)
Posterior (occipital) (1)
Anterolateral (sphenoidal) (R,L)
Posterolateral (mastoid) (R,L)

Paranasal Sinuses

Maxillary (R,L)
Frontal (1)
Sphenoid (1)
Ethmoid air cells (many)

Hyoid Bone (feel)

Vertebral Column

Vertebrae

cervical (7)
thoracic (12)
lumbar (5)
sacral (5 in children)
coccygeal vertebrae (4 in children)

Sacrum (1) (5 fused vertebrae in adults)

Coccyx (1) (4 fused vertebrae in adults)

Cervical, thoracic, lumbar, and sacral curves.

Know the structure of a typical vertebra including

the body
pedicle
lamina
vertebral arch
vertebral foramen
transverse process
spinous process (feel the spinal process of the 7^th cervical vertebra, aka the vertebra prominens),
superior and inferior articulating processes
intervertebral foramen (formed when two successive vertebrae are fitted together)

Be able to recognize a cervical, thoracic, lumbar, sacral, or coccygeal vertebra; know the number of each.

Transverse foramina of the cervical vertebrae

Atlas (C1)
Axis (C2)

dens

Thoracic vertebrae

Rib facets

Sternum and Ribs (Thorax)

Sternum (1)

manubrium
body (gladiolus)
sternal angle (feel)
xiphoid process (feel)
suprasternal (jugular) notch (feel)

Ribs (12 pairs) (7 pairs of “true” ribs, 5 pairs of “false” ribs, [the last 2 pairs of which are “floating” ribs]

head
tubercle
facets

Be able to identify the 1^st rib and inferior costal margin (feel)

THE APPENDICULAR SKELETON

Pectoral (Shoulder) Girdle

Clavicle (feel) (R,L)

sternal extremity
acromial extremity

Scapula (R,L)

acromion (feel)
glenoid cavity
supraglenoid tubercle
coracoid process
spine (feel)
vertebral and axillary border
supra- and infraspinous fossae
subscapular fossa
inferior angle

Upper Extremity

Humerus (R, L)

head
anatomical neck
greater tubercle
lesser tubercle
surgical neck
deltoid tuberosity
capitulum
trochlea
coronoid fossa
olecranon fossa
medial and lateral epicondyles (feel)
intertubercular sulcus (groove)

Ulna (R,L)

olecranon process (feel)
trochlear notch
coronoid process
radial notch
styloid process (feel)
head

Radius (R,L)

head
radial tuberosity
styloid process (feel)
ulnar notch

Carpus (aka carpals) (8 per hand)

Proximal row

pisiform (feel)
triquetrum
lunate
scaphoid

Distal row

hamate
capitate
trapezoid
trapezium

Metacarpals (5 per hand) (feel the distal epiphyses of the metacarpals—what else are these called?)

Phalanges (14 per hand); singular is phalanx.

Pelvic (Hip) Girdle (formed by the two coxal bones, aka the os coxae or pelvic bones; the coxal bone is formed by the fused ilium, ischium, and pubis)

Ilium (R,L)

iliac crest (feel)
anterior superior iliac spine (feel)
anterior inferior iliac spine
iliac fossa

Ischium (R,L)

ischial tuberosity (feel)
ramus

Pubis (R,L)

pubic symphysis
superior and inferior rami

Acetabulum of the coxal bone

The Pelvis (pelvic girdle plus the sacrum and coccyx)

Greater (false) pelvis
Lesser (true) pelvis
Pelvic inlet and outlet

Distinguish between male and female pelvises

Lower Extremities

Femur (R,L)

head
fovea capitis
neck
greater trochanter (feel)
lesser trochanter
gluteal tuberosity
linea aspera
lateral and medial condyles
lateral and medial epicondyles (feel)

Patella (feel) (R,L)

Tibia (R,L)

lateral and medial condyles
tibial tuberosity (feel)
medial malleolus (feel)

Fibula (R, L)

head
lateral malleolus (feel)

Tarsals (aka tarsus) (7 per foot)

Posterior

talus
calcaneus (feel)

Anterior

cuboid
navicular
3 cuneiforms

Metatarsals (5 per foot) (feel the base of the 5^th metatarsal)

Phalanges (14 per foot); singular is phalanx.

JOINTS

Identify the following on the knee joint model

articular cartilage
anterior cruciate ligament (ACL)
posterior cruciate ligament (PCL)
lateral and medial collateral ligaments
menisci.

Some Clinically Relevant Bony Landmarks
clavicle	used to locate the subclavian vein for insertion of central intravenous catheter also used to find jugular veins.
xiphoid process	used to position stethoscope to auscultate the tricuspid valve; process used as a landmark to measure length of NG tubes.
greater trochanter, anterior superior iliac spine (ASIS) and iliac crest	used to locate IM injections in the hip
ASIS	used to locate McBurney’s point for assessment of appendicitis (McBurney’s point is halfway between the ASIS and umbilicus)
sternal angle	used to locate proper position for CPR used to count ribs (2^nd rib joins sternum at the sternal angle)
spinous processes	used to locate points for lumbar punctures and epidurals.
greater tubercle and deltoid tuberosity	used to locate IM (intramuscular) injections in the shoulder
inferior costal margin	used to assess pathology of internal organs (e.g. hepatomegaly)
occipital bone, spine of the scapula, olecranon process, sacrum, coccyx, ischialtuberosity, greater trochanter, calcaneus, lateral and medial malleolus, medial condyle of tibia	all are common sites for pressure sores (“bed sores”)
styloid process of radius	used to locate site for radial pulse
supraorbital ridge and zygomatic bones	palpated to assess sinus infections
vertebra prominens	used to find the end of the cervical spine and beginning of thoracic spine. Can be used to count ribs.
sternum, clavicles, scapula, and spinous processes of vertebra	used to identify location of the midsternal, midclavicular, scapular and vertebral lines of the thorax.
medial malleolus	used to locate posterior tibial pulse.
posterior superior iliac spine	site of bone marrow biopsy.
spinal curvatures	used to assess for kyphosis and lordosis .
pubic symphysis	used to locate incision for placement of catheter for suprapubic bladder drainage.
olecranon process	used to locate triceps tendon for reflex testing.
patella	used to locate patellar tendon for reflex testing
any bony point at joints	used to assess joint health. Obscured bony landmarks may suggest joint swelling. If bony points are misaligned a fracture or dislocation in suggested.

Some Clinically Relevant Bony Landmarks