Chapter 8: Appendicular Skeleton: Key Terms

trochlear notch

large, C-shaped depression located on the anterior side of the proximal ulna; articulates at the elbow with the trochlea of the humerus

midcarpal joint

articulation between the proximal and distal rows of the carpal bones; contributes to movements of the hand at the wrist

proximal radioulnar joint

articulation formed by the radial notch of the ulna and the head of the radius

costoclavicular ligament

band of connective tissue that unites the medial clavicle with the first rib

intertubercular groove (sulcus)

bicipital groove; narrow groove located between the greater and lesser tubercles of the humerus

hallux

big toe; digit 1 of the foot

radius

bone located on the lateral side of the forearm

ulna

bone located on the medial side of the forearm

medial malleolus

bony expansion located on the medial side of the distal tibia

hook of the hamate bone

bony extension located on the anterior side of the hamate carpal bone

ischial ramus

bony extension projecting anteriorly and superiorly from the ischial tuberosity; joins with the inferior pubic ramus to form the ischiopubic ramus

sustentaculum tali

bony ledge extending from the medial side of the calcaneus bone

pubic arch

bony structure formed by the pubic symphysis, and the bodies and inferior pubic rami of the right and left pubic bones

subscapular fossa

broad depression located on the anterior (deep) surface of the scapula

infraspinous fossa

broad depression located on the posterior scapula, inferior to the spine

trapezoid

from the lateral side, the second of the four distal carpal bones; articulates with the scaphoid proximally, the second metacarpal distally, the trapezium laterally, and the capitate medially

lunate

from the lateral side, the second of the four proximal carpal bones; articulates with the radius proximally, the capitate and hamate distally, the scaphoid laterally, and the triquetrum medially

pisiform

from the lateral side, the fourth of the four proximal carpal bones; articulates with the anterior surface of the triquetrum

olecranon fossa

large depression located on the posterior side of the distal humerus; this space receives the olecranon process of the ulna when the elbow is fully extended

obturator foramen

large opening located in the anterior hip bone, between the pubis and ischium regions

greater sciatic notch

large, U-shaped indentation located on the posterior margin of the ilium, superior to the ischial spine

greater trochanter

large, bony expansion of the femur that projects superiorly from the base of the femoral neck

acetabulum

large, cup-shaped cavity located on the lateral side of the hip bone; formed by the junction of the ilium, pubis, and ischium portions of the hip bone

head of the femur

rounded, proximal end of the femur that articulates with the acetabulum of the hip bone to form the hip joint

intertrochanteric line

small ridge running between the greater and lesser trochanters on the anterior side of the proximal femur

glenoid cavity

(also, glenoid fossa) shallow depression located on the lateral scapula, between the superior and lateral borders

greater pelvis

(also, greater pelvic cavity or false pelvis) broad space above the pelvic brim defined laterally by the fan-like portion of the upper ilium

lesser pelvis

(also, lesser pelvic cavity or true pelvis) narrow space located within the pelvis, defined superiorly by the pelvic brim (pelvic inlet) and inferiorly by the pelvic outlet

pollex

(also, thumb) digit 1 of the hand

fossa

(plural = fossae) shallow depression on the surface of a bone

phalanx bone of the hand

(plural = phalanges) one of the 14 bones that form the thumb and fingers; these include the proximal and distal phalanges of the thumb, and the proximal, middle, and distal phalanx bones of the fingers two through five

phalanx bone of the foot

(plural = phalanges) one of the 14 bones that form the toes; these include the proximal and distal phalanges of the big toe, and the proximal, middle, and distal phalanx bones of toes two through five

base of the metatarsal bone

expanded, proximal end of each metatarsal bone

acromial process

acromion of the scapula

pubis

anterior portion of the hip bone

metatarsophalangeal joint

articulation between a metatarsal bone of the foot and the proximal phalanx bone of a toe

interphalangeal joint

articulation between adjacent phalanx bones of the hand or foot digits

carpometacarpal joint

articulation between one of the carpal bones in the distal row and a metacarpal bone of the hand

acromioclavicular joint

articulation between the acromion of the scapula and the acromial end of the clavicle

metacarpophalangeal joint

articulation between the distal end of a metacarpal bone of the hand and a proximal phalanx bone of the thumb or a finger

distal tibiofibular joint

articulation between the distal fibula and the fibular notch of the tibia

proximal tibiofibular joint

articulation between the head of the fibula and the inferior aspect of the lateral condyle of the tibia

distal radioulnar joint

articulation between the head of the ulna and the ulnar notch of the radius

sternoclavicular joint

articulation between the manubrium of the sternum and the sternal end of the clavicle; forms the only bony attachment between the pectoral girdle of the upper limb and the axial skeleton

clavicle

collarbone; elongated bone that articulates with the manubrium of the sternum medially and the acromion of the scapula laterally

olecranon process

expanded posterior and superior portions of the proximal ulna; forms the bony tip of the elbow

superior angle of the scapula

corner of the scapula between the superior and medial borders of the scapula

hip bone

coxal bone; single bone that forms the pelvic girdle; consists of three areas, the ilium, ischium, and pubis

iliac crest

curved, superior margin of the ilium

shaft of the femur

cylindrically shaped region that forms the central portion of the femur

intercondylar fossa

deep depression on the posterior side of the distal femur that separates the medial and lateral condyles

coronoid fossa

depression on the anterior surface of the humerus above the trochlea; this space receives the coronoid process of the ulna when the elbow is maximally flexed

lateral border of the scapula

diagonally oriented lateral margin of the scapula

head of the radius

disc-shaped structure that forms the proximal end of the radius; articulates with the capitulum of the humerus as part of the elbow joint, and with the radial notch of the ulna as part of the proximal radioulnar joint

tibial tuberosity

elevated area on the anterior surface of the proximal tibia

medial border of the scapula

elongated, medial margin of the scapula

shaft of the fibula

elongated, slender portion located between the expanded ends of the fibula

medial epicondyle of the humerus

enlarged projection located on the medial side of the distal humerus

greater tubercle

enlarged prominence located on the lateral side of the proximal humerus

apical ectodermal ridge

enlarged ridge of ectoderm at the distal end of a limb bud that stimulates growth and elongation of the limb

pubic body

enlarged, medial portion of the pubis region of the hip bone

lateral malleolus

expanded distal end of the fibula

head of the metatarsal bone

expanded, distal end of each metatarsal bone

acromion

flattened bony process that extends laterally from the scapular spine to form the bony tip of the shoulder

trapezium

from the lateral side, the first of the four distal carpal bones; articulates with the scaphoid proximally, the first and second metacarpals distally, and the trapezoid medially

scaphoid

from the lateral side, the first of the four proximal carpal bones; articulates with the radius proximally, the trapezoid, trapezium, and capitate distally, and the lunate medially

hamate

from the lateral side, the fourth of the four distal carpal bones; articulates with the lunate and triquetrum proximally, the fourth and fifth metacarpals distally, and the capitate laterally

capitate

from the lateral side, the third of the four distal carpal bones; articulates with the scaphoid and lunate proximally, the trapezoid laterally, the hamate medially, and primarily with the third metacarpal distally

triquetrum

from the lateral side, the third of the four proximal carpal bones; articulates with the lunate laterally, the hamate distally, and has a facet for the pisiform

calcaneus

heel bone; posterior, inferior tarsal bone that forms the heel of the foot

coxal bone

hip bone

pelvic girdle

hip girdle; consists of a single hip bone, which attaches a lower limb to the sacrum of the axial skeleton

inferior angle of the scapula

inferior corner of the scapula located where the medial and lateral borders meet

pelvic outlet

inferior opening of the lesser pelvis; formed by the inferior margin of the pubic symphysis, right and left ischiopubic rami and sacrotuberous ligaments, and the tip of the coccyx

bicipital groove

intertubercular groove; narrow groove located between the greater and lesser tubercles of the humerus

subpubic angle

inverted V-shape formed by the convergence of the right and left ischiopubic rami; this angle is greater than 80 degrees in females and less than 70 degrees in males

intercondylar eminence

irregular elevation on the superior end of the tibia, between the articulating surfaces of the medial and lateral condyles

sacroiliac joint

joint formed by the articulation between the auricular surfaces of the sacrum and ilium

pubic symphysis

joint formed by the articulation between the pubic bodies of the right and left hip bones

hip joint

joint located at the proximal end of the lower limb; formed by the articulation between the acetabulum of the hip bone and the head of the femur

elbow joint

joint located between the upper arm and forearm regions of the upper limb; formed by the articulations between the trochlea of the humerus and the trochlear notch of the ulna, and the capitulum of the humerus and the head of the radius

ankle joint

joint that separates the leg and foot portions of the lower limb; formed by the articulations between the talus bone of the foot inferiorly, and the distal end of the tibia, medial malleolus of the tibia, and lateral malleolus of the fibula superiorly

knee joint

joint that separates the thigh and leg portions of the lower limb; formed by the articulations between the medial and lateral condyles of the femur, and the medial and lateral condyles of the tibia

patella

kneecap; the largest sesamoid bone of the body; articulates with the distal femur

capitulum

knob-like bony structure located anteriorly on the lateral, distal end of the humerus

ischial tuberosity

large, roughened protuberance that forms the posteroinferior portion of the hip bone; weight-bearing region of the pelvis when sitting

acromial end of the clavicle

lateral end of the clavicle that articulates with the acromion of the scapula

lateral condyle of the tibia

lateral, expanded region of the proximal tibia that includes the smooth surface that articulates with the lateral condyle of the femur as part of the knee joint

ligament of the head of the femur

ligament that spans the acetabulum of the hip bone and the fovea capitis of the femoral head

sacrospinous ligament

ligament that spans the sacrum to the ischial spine of the hip bone

sacrotuberous ligament

ligament that spans the sacrum to the ischial tuberosity of the hip bone

anatomical neck

line on the humerus located around the outside margin of the humeral head

linea aspera

longitudinally running bony ridge located in the middle third of the posterior femur

sternal end of the clavicle

medial end of the clavicle that articulates with the manubrium of the sternum

medial condyle of the tibia

medial, expanded region of the proximal tibia that includes the smooth surface that articulates with the medial condyle of the femur as part of the knee joint

intermediate cuneiform

middle of the three cuneiform tarsal bones; articulates posteriorly with the navicular bone, medially with the medial cuneiform bone, laterally with the lateral cuneiform bone, and anteriorly with the second metatarsal bone

fovea capitis

minor indentation on the head of the femur that serves as the site of attachment for the ligament to the head of the femur

lateral cuneiform

most lateral of the three cuneiform tarsal bones; articulates posteriorly with the navicular bone, medially with the intermediate cuneiform bone, laterally with the cuboid bone, and anteriorly with the third metatarsal bone

medial cuneiform

most medial of the three cuneiform tarsal bones; articulates posteriorly with the navicular bone, laterally with the intermediate cuneiform bone, and anteriorly with the first and second metatarsal bones

supraspinous fossa

narrow depression located on the posterior scapula, superior to the spine

ischiopubic ramus

narrow extension of bone that connects the ischial tuberosity to the pubic body; formed by the junction of the ischial ramus and inferior pubic ramus

interosseous border of the ulna

narrow ridge located on the lateral side of the ulnar shaft; for attachment of the interosseous membrane between the ulna and radius

interosseous border of the radius

narrow ridge located on the medial side of the radial shaft; for attachment of the interosseous membrane between the ulna and radius bones

pectineal line

narrow ridge located on the superior surface of the superior pubic ramus

inferior pubic ramus

narrow segment of bone that passes inferiorly and laterally from the pubic body; joins with the ischial ramus to form the ischiopubic ramus

superior pubic ramus

narrow segment of bone that passes laterally from the pubic body to join the ilium

anterior border of the tibia

narrow, anterior margin of the tibia that extends inferiorly from the tibial tuberosity

lateral supracondylar ridge

narrow, bony ridge located along the lateral side of the distal humerus, superior to the lateral epicondyle

shaft of the humerus

narrow, elongated, central region of the humerus

shaft of the radius

narrow, elongated, central region of the radius

shaft of the ulna

narrow, elongated, central region of the ulna

neck of the radius

narrowed region immediately distal to the head of the radius

neck of the femur

narrowed region located inferior to the head of the femur

carpal bone

one of the eight small bones that form the wrist and base of the hand; these are grouped as a proximal row consisting of (from lateral to medial) the scaphoid, lunate, triquetrum, and pisiform bones, and a distal row containing (from lateral to medial) the trapezium, trapezoid, capitate, and hamate bones

metatarsal bone

one of the five elongated bones that forms the anterior half of the foot; numbered 1-5, starting on the medial side of the foot

metacarpal bone

one of the five long bones that form the palm of the hand; numbered 1-5, starting on the lateral (thumb) side of the hand

tarsal bone

one of the seven bones that make up the posterior foot; includes the calcaneus, talus, navicular, cuboid, medial cuneiform, intermediate cuneiform, and lateral cuneiform bones

radial tuberosity

oval-shaped, roughened protuberance located on the medial side of the proximal radius

carpal tunnel

passageway between the anterior forearm and hand formed by the carpal bones and flexor retinaculum

pelvic inlet

pelvic brim

pelvic brim

pelvic inlet; the dividing line between the greater and lesser pelvic regions; formed by the superior margin of the pubic symphysis, the pectineal lines of each pubis, the arcuate lines of each ilium, and the sacral promontory

greater sciatic foramen

pelvic opening formed by the greater sciatic notch of the hip bone, the sacrum, and the sacrospinous ligament

lesser sciatic foramen

pelvic opening formed by the lesser sciatic notch of the hip bone, the sacrospinous ligament, and the sacrotuberous ligament

styloid process of the radius

pointed projection located on the lateral end of the distal radius

ischial spine

pointed, bony projection from the posterior margin of the ischium that separates the greater sciatic notch and lesser sciatic notch

thigh

portion of the lower limb located between the hip and knee joints

leg

portion of the lower limb located between the knee and ankle joints

foot

portion of the lower limb located distal to the ankle joint

ischium

posteroinferior portion of the hip bone

coronoid process of the ulna

projecting bony lip located on the anterior, proximal ulna; forms the inferior margin of the trochlear notch

spine of the scapula

prominent ridge passing mediolaterally across the upper portion of the posterior scapular surface

lateral epicondyle of the humerus

small projection located on the lateral side of the distal humerus

trochlea

pulley-shaped region located medially at the distal end of the humerus; articulates at the elbow with the trochlear notch of the ulna

surgical neck

region of the humerus where the expanded, proximal end joins with the narrower shaft

hand

region of the upper limb distal to the wrist joint

forearm

region of the upper limb located between the elbow and wrist joints; contains the radius and ulna bones

arm

region of the upper limb located between the shoulder and elbow joints; contains the humerus bone

pelvis

ring of bone consisting of the right and left hip bones, the sacrum, and the coccyx

ulnar tuberosity

roughened area located on the anterior, proximal ulna inferior to the coronoid process

auricular surface of the ilium

roughened area located on the posterior, medial side of the ilium of the hip bone; articulates with the auricular surface of the sacrum to form the sacroiliac joint

medial epicondyle of the femur

roughened area of the distal femur located on the medial side of the medial condyle

lateral epicondyle of the femur

roughened area of the femur located on the lateral side of the lateral condyle

gluteal tuberosity

roughened area on the posterior side of the proximal femur, extending inferiorly from the base of the greater trochanter

deltoid tuberosity

roughened, V-shaped region located laterally on the mid-shaft of the humerus

anterior superior iliac spine

rounded, anterior end of the iliac crest

posterior superior iliac spine

rounded, posterior end of the iliac crest

iliac fossa

shallow depression found on the anterior and medial surfaces of the upper ilium

lesser sciatic notch

shallow indentation along the posterior margin of the ischium, inferior to the ischial spine

ulnar notch of the radius

shallow, smooth area located on the medial side of the distal radius; articulates with the head of the ulna at the distal radioulnar joint

interosseous membrane of the forearm

sheet of dense connective tissue that unites the radius and ulna bones

interosseous membrane of the leg

sheet of dense connective tissue that unites the shafts of the tibia and fibula bones

tibia

shin bone; the large, weight-bearing bone located on the medial side of the leg

styloid process of the ulna

short, bony projection located on the medial end of the distal ulna

coracoid process

short, hook-like process that projects anteriorly and laterally from the superior margin of the scapula

intertrochanteric crest

short, prominent ridge running between the greater and lesser trochanters on the posterior side of the proximal femur

scapula

shoulder blade bone located on the posterior side of the shoulder

pectoral girdle

shoulder girdle; the set of bones, consisting of the scapula and clavicle, which attaches each upper limb to the axial skeleton

glenohumeral joint

shoulder joint; formed by the articulation between the glenoid cavity of the scapula and the head of the humerus

humerus

single bone of the upper arm

supraglenoid tubercle

small bump located at the superior margin of the glenoid cavity

pubic tubercle

small bump located on the superior aspect of the pubic body

infraglenoid tubercle

small bump or roughened area located on the lateral border of the scapula, near the inferior margin of the glenoid cavity

radial fossa

small depression located on the anterior humerus above the capitulum; this space receives the head of the radius when the elbow is maximally flexed

limb bud

small elevation that appears on the lateral side of the embryo during the fourth or fifth week of development, which gives rise to an upper or lower limb

suprascapular notch

small notch located along the superior border of the scapula, medial to the coracoid process

interosseous border of the tibia

small ridge running down the lateral side of the tibial shaft; for attachment of the interosseous membrane between the tibia and fibula

interosseous border of the fibula

small ridge running down the medial side of the fibular shaft; for attachment of the interosseous membrane between the fibula and tibia

adductor tubercle

small, bony bump located on the superior aspect of the medial epicondyle of the femur

posterior inferior iliac spine

small, bony projection located at the inferior margin of the auricular surface on the posterior ilium

anterior inferior iliac spine

small, bony projection located on the anterior margin of the ilium, below the anterior superior iliac spine

lesser trochanter

small, bony projection on the medial side of the proximal femur, at the base of the femoral neck

lesser tubercle

small, bony prominence located on anterior side of the proximal humerus

soleal line

small, diagonally running ridge located on the posterior side of the proximal tibia

head of the fibula

small, knob-like, proximal end of the fibula; articulates with the inferior aspect of the lateral condyle of the tibia

head of the ulna

small, rounded distal end of the ulna; articulates with the ulnar notch of the distal radius, forming the distal radioulnar joint

radial notch of the ulna

small, smooth area on the lateral side of the proximal ulna; articulates with the head of the radius as part of the proximal radioulnar joint

patellar surface

smooth groove located on the anterior side of the distal femur, between the medial and lateral condyles; site of articulation for the patella

arcuate line of the ilium

smooth ridge located at the inferior margin of the iliac fossa; forms the lateral portion of the pelvic brim

lateral condyle of the femur

smooth, articulating surface that forms the distal and posterior sides of the lateral expansion of the distal femur

medial condyle of the femur

smooth, articulating surface that forms the distal and posterior sides of the medial expansion of the distal femur

head of the humerus

smooth, rounded region on the medial side of the proximal humerus; articulates with the glenoid fossa of the scapula to form the glenohumeral (shoulder) joint

flexor retinaculum

strong band of connective tissue at the anterior wrist that spans the top of the U-shaped grouping of the carpal bones to form the roof of the carpal tunnel

coracoclavicular ligament

strong band of connective tissue that anchors the coracoid process of the scapula to the lateral clavicle; provides important indirect support for the acromioclavicular joint

anterior sacroiliac ligament

strong ligament between the sacrum and the ilium portions of the hip bone that supports the anterior side of the sacroiliac joint

posterior sacroiliac ligament

strong ligament spanning the sacrum and ilium of the hip bone that supports the posterior side of the sacroiliac joint

superior border of the scapula

superior margin of the scapula

ilium

superior portion of the hip bone

cuboid

tarsal bone that articulates posteriorly with the calcaneus bone, medially with the lateral cuneiform bone, and anteriorly with the fourth and fifth metatarsal bones

navicular

tarsal bone that articulates posteriorly with the talus bone, laterally with the cuboid bone, and anteriorly with the medial, intermediate, and lateral cuneiform bones

talus

tarsal bone that articulates superiorly with the tibia and fibula at the ankle joint; also articulates inferiorly with the calcaneus bone and anteriorly with the navicular bone

femur

thigh bone; the single bone of the thigh

fibula

thin, non-weight-bearing bone found on the lateral side of the leg

shaft of the tibia

triangular-shaped, central portion of the tibia

fibular notch

wide groove on the lateral side of the distal tibia for articulation with the fibula at the distal tibiofibular joint

radiocarpal joint

wrist joint, located between the forearm and hand regions of the upper limb; articulation formed proximally by the distal end of the radius and the fibrocartilaginous pad that unites the distal radius and ulna bone, and distally by the scaphoid, lunate, and triquetrum carpal bones