Bones, Part 2: The Appendicular Skeleton

Vocabulary flashcards covering major bones, landmarks, and structural features of the appendicular skeleton as presented in the lecture.

Appendicular Skeleton

Portion of the skeleton consisting of the pectoral girdle, pelvic girdle, upper limbs, and lower limbs.

Pectoral Girdle

Clavicle + scapula; light girdle that attaches the upper limb to the trunk and permits high mobility.

Pelvic Girdle

Paired hip (coxal) bones plus sacrum; attaches lower limbs to spine, supports viscera, deep acetabulum adds stability.

Clavicle

S-shaped bone whose sternal end articulates with the manubrium and acromial end with the scapula; transmits upper-limb compression to axial skeleton.

Sternal End (Clavicle)

Medial, cone-shaped end of clavicle that joins the manubrium of the sternum.

Acromial End (Clavicle)

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

Scapula

Triangular bone on dorsal ribs 2–7; has superior, medial, and lateral borders and superior, lateral, inferior angles.

Glenoid Cavity

Shallow socket on scapula that receives head of humerus; allows flexibility but less stability (shoulder dislocations).

Coracoid Process

Anterior projection of scapula serving as biceps brachii attachment.

Acromion

Lateral extension of scapular spine; articulates with acromial end of clavicle.

Scapular Spine

Prominent ridge on posterior scapula ending laterally in the acromion.

Arm (Brachium)

Region between shoulder and elbow; contains only the humerus.

Humerus

Longest, strongest bone of upper limb; proximal head fits glenoid cavity, distal end forms elbow with radius (capitulum) and ulna (trochlea).

Capitulum

Lateral condyle of distal humerus that articulates with head of radius.

Trochlea

Spool-shaped medial condyle of humerus that articulates with ulna.

Medial Epicondyle (Humerus)

Medial projection for forearm-muscle attachment.

Lateral Epicondyle (Humerus)

Lateral projection for forearm-muscle attachment.

Tubercles (Greater & Lesser)

Proximal humeral bumps that anchor rotator-cuff muscles.

Deltoid Tuberosity

Lateral shaft roughening where deltoid muscle inserts.

Radial Groove

Posterior oblique groove on humerus carrying radial nerve.

Forearm

Region between elbow and wrist; formed by radius and ulna joined by interosseous membrane.

Interosseous Membrane

Fibrous sheet connecting shafts of radius and ulna (and tibia–fibula in leg).

Ulna

Medial forearm bone forming hinge elbow with humerus; distal head separated from carpals by fibrocartilage.

Olecranon

Proximal ulna projection forming elbow tip; triceps attachment.

Trochlear Notch

Deep curved surface on ulna that grasps trochlea of humerus.

Coronoid Process

Anterior ulna projection completing trochlear notch; enters coronoid fossa during flexion.

Radial Notch

Lateral proximal ulna depression where head of radius pivots (proximal radioulnar joint).

Ulnar Styloid Process

Distal pointed projection anchoring wrist ligaments.

Radius

Lateral forearm bone; head articulates with capitulum (humerus) and radial notch (ulna); distal end forms major wrist joint.

Radial Tuberosity

Medial proximal bump for biceps brachii insertion.

Radial Styloid Process

Distal lateral projection anchoring wrist ligaments; palpated at wrist.

Carpus

Wrist; eight carpal bones in two rows allowing gliding; houses carpal tunnel for median nerve.

Scaphoid

Boat-shaped lateral carpal in proximal row; commonly fractured.

Lunate

Crescent-shaped carpal next to scaphoid in proximal row.

Triquetrum

Proximal-row carpal medial to lunate.

Pisiform

Pea-shaped sesamoid carpal sitting anterior to triquetrum.

Trapezium

Most lateral distal-row carpal; articulates with thumb metacarpal.

Trapezoid

Small distal-row carpal between trapezium and capitate.

Capitate

Largest carpal; central bone of distal row.

Hamate

Medial distal-row carpal with hook-like projection.

Metacarpus

Palm; five metacarpal bones (I–V) radiating from distal carpals to proximal phalanges.

Phalanges (Hand)

Digital bones; each finger has proximal, middle, distal phalanges except thumb (pollex) which lacks middle.

Pollex

Thumb; metacarpal I and two phalanges, provides precision grip.

Coxal (Hip) Bone

Fusion of ilium, ischium, and pubis; unites at pubic symphysis anteriorly and sacrum posteriorly.

Acetabulum

Deep lateral socket of coxal bone receiving femoral head.

Ilium

Superior part of hip bone; auricular surface articulates with sacrum at sacroiliac joint.

Ischium

Posteroinferior hip bone portion; features ischial tuberosity for weight bearing.

Ischial Tuberosity

Thick inferior projection of ischium; bears body weight when sitting.

Pubis

Anterior hip bone portion; left & right join at fibrocartilaginous pubic symphysis.

Pubic Arch

Angle below pubic symphysis; wider in females, helps sex differentiation.

Femur

Longest, strongest bone; head fits acetabulum, distal condyles articulate with tibia, patellar surface anterior.

Fovea Capitis

Pit on femoral head where ligament secures femur to acetabulum.

Greater Trochanter

Large lateral femoral projection for muscle attachment.

Lesser Trochanter

Posteromedial femoral projection for muscle attachment.

Linea Aspera

Long ridge on posterior femoral shaft serving multiple muscle attachments.

Medial & Lateral Condyles (Femur)

Rounded distal surfaces that articulate with tibial condyles at knee.

Patellar Surface

Anterior distal femur groove where patella glides.

Patella

Triangular sesamoid bone in quadriceps tendon; protects knee and improves leverage.

Leg (Crus)

Region between knee and ankle; composed of tibia (medial weight-bearing) and fibula (lateral slender).

Tibia

Larger medial leg bone; receives body weight from femur and transmits to foot; forms knee (superior) and ankle (inferior) joints.

Medial Malleolus

Distal tibial projection forming medial bulge of ankle; articulates with talus.

Fibula

Lateral leg bone; stabilizes ankle, does not bear weight nor articulate with femur.

Tarsus

Posterior half of foot; seven tarsal bones including talus and calcaneus.

Talus

Superior tarsal whose trochlea articulates with tibia/fibula at ankle joint.

Calcaneus

Heel bone; largest tarsal bearing body weight.

Cuboid

Lateral tarsal anterior to calcaneus; keystone of lateral longitudinal arch.

Navicular

Medial tarsal between talus and cuneiforms.

Cuneiforms (Medial, Intermediate, Lateral)

Three wedge-shaped tarsals anterior to navicular.

Metatarsus

Five metatarsal bones (I–V) forming anterior foot; metatarsal I (hallux) supports body weight.

Hallux

Great toe; metatarsal I plus two phalanges (proximal & distal).

Phalanges (Foot)

14 toe bones; each toe has proximal, middle, distal phalanges except hallux lacking middle.

Arches of the Foot

Medial & lateral longitudinal and transverse arches maintained by bone shapes, ligaments, tendons, and keystone bones (talus, cuboid).