Appendicular Skeleton: Upper and Lower Limbs & Pelvic and Pectoral Girdles

Comprehensive vocabulary flashcards covering the osteological features, joints, muscle attachments, and structural differences of the appendicular skeleton, including the pectoral girdle, upper limb, pelvic girdle, and lower limb.

Pectoral Girdle

Also known as the shoulder girdle; formed by the anterior clavicle and posterior scapula, attaching the upper limbs to the axial skeleton.

Clavicle

A slender, rodlike bone with an elongated S-shape situated at the base of the neck between the sternum and scapula.

Sternal End of Clavicle

The medial end of the clavicle that attaches to the manubrium of the sternum.

Acromial End of Clavicle

The lateral end of the clavicle that articulates with the acromion process of the scapula.

Scapula

A flat triangular bone lying on the dorsal surface of the thoracic cage between ribs 2 and 7; features superior, medial (vertebral), and lateral (axillary) borders.

Glenoid Cavity

A shallow socket on the lateral aspect of the scapula that articulates with the head of the humerus.

Coracoid Process

A projection on the anterior scapula that serves as the attachment site for the short head of the biceps muscle.

Acromioclavicular (AC) Joint

The joint connecting the acromion process of the scapula to the acromial end of the clavicle.

Glenohumeral Joint

The shoulder joint where the head of the humerus (ball) meets the glenoid cavity of the scapula (socket); provides high mobility but poor stability.

Rotator Cuff

A group of four small muscles in the shoulder consisting of the supraspinatus, infraspinatus, teres minor, and subscapularis.

Humerus

The arm bone located between the scapula and elbow; features a head, anatomical neck, surgical neck, greater and lesser tubercles, and distal articular condyles.

Surgical Neck of Humerus

The region located immediately distal to the tubercles of the humerus that is a frequent site of fractures.

Deltoid Tuberosity

A rough, elevated area on the shaft of the humerus providing an attachment point for the deltoid muscle.

Capitulum

The lateral condyle on the distal humerus that articulates with the head of the radius.

Trochlea

The pulley-shaped medial condyle on the distal humerus that articulates with the trochlear notch of the ulna.

Olecranon Fossa

A posterior depression on the distal humerus that receives the olecranon process of the ulna when the elbow extends.

Coronoid Fossa

An anterior depression on the distal humerus that receives the coronoid process of the ulna during elbow flexion.

Radius

The lateral bone of the forearm located on the thumb side; articulates proximally with the capitulum of the humerus and distally with the scaphoid and lunate bones.

Ulna

The medial bone of the forearm located between the elbow and wrist; contains the trochlear notch, olecranon process, coronoid process, and head.

Trochlear Notch

A large, wrench-shaped indentation on the proximal ulna that articulates with the trochlea of the humerus.

Olecranon Process

A prominent posterior projection at the proximal end of the ulna that forms the point of the elbow.

Carpals

The 8 wrist bones organized into two rows of four: proximal row (scaphoid, lunate, triquetrum, pisiform) and distal row (trapezium, trapezoid, capitate, hamate).

Metacarpals

The 5 palm bones numbered 1 through 5 in line with each finger starting from the thumb side.

Hand Phalanges

The 14 bones of the fingers: two in the thumb (proximal and distal) and three in each of the remaining four digits (proximal, middle, distal).

Pelvic Girdle

Composed of two hip (coxal/pelvic) bones that attach the lower limbs to the axial skeleton; prioritizes stability over mobility.

Pelvis

A composite structure consisting of the two hip (coxal) bones, the sacrum, and the coccyx.

Coxal Bone

The hip bone formed by the adulthood fusion of three separate bones: the ilium, ischium, and pubis.

Acetabulum

A deep socket on the lateral surface of the hip bone formed by the fusion of the ilium, ischium, and pubis; articulates with the head of the femur.

Ilium

The largest and most superior portion of the coxal bone; features the iliac crest, anterior superior iliac spine (ASIS), greater sciatic notch, and sacroiliac joint surface.

Anterior Superior Iliac Spine (ASIS)

A distinct anterior prominence on the margin of the iliac crest that serves as an attachment site for muscles and ligaments.

Greater Sciatic Notch

A deep indentation on the posterior border of the ilium through which nerves and blood vessels pass into the lower limb.

Ischium

The inferior and posterior portion of each coxal bone.

Ischial Tuberosity

The rough, thick inferior projection of the ischium that supports body weight while seated and attaches the sacrotuberous ligament.

Pubis

The anterior portion of the hip bone that supports the urinary bladder and participates in the pubic symphysis.

Pubic Symphysis

The joint formed along the anterior pelvic midline where the two pubic bones meet.

Obturator Foramen

The large opening enclosed between the pubis and ischium through which few structures pass.

Female Pelvis

Demonstrates more flared iliac bones and wider pelvic inlet and outlet spaces than the male pelvis to facilitate childbirth.

Femur

The thigh bone; the longest, biggest, and strongest bone in the body, measuring approximately $\frac{1}{4}$ of human stature.

Neck of Femur

The constricted segment connecting the head to the femoral shaft; it is the structurally weakest point of the femur and the primary site for hip fractures.

Fovea Capitis

A small pit on the head of the femur that provides attachment for a stabilizing ligament.

Linea Aspera

A prominent longitudinal ridge on the posterior surface of the femoral shaft serving as an attachment point for muscles.

Patella

The kneecap; a sesamoid bone located within the quadriceps tendon that articulates with the patellar surface of the distal femur.

Tibia

The medial bone of the lower leg (shin); bears body weight and articulates proximally with the femur and distally with the talus.

Tibial Tuberosity

A raised rough area on the proximal anterior surface of the tibia that serves as the attachment point for the patellar ligament.

Medial Malleolus

A prominent distal projection on the medial side of the tibia that forms the inner bulge of the ankle.

Fibula

The lateral bone of the lower leg; non-weight-bearing, non-articulating with the femur, and vital for muscle attachment and ankle stability.

Lateral Malleolus

The distal expansion of the fibula that forms the lateral bulge of the ankle and provides lateral stability.

Tibiofibular Joints

The proximal and distal articulations between the tibia and fibula connected by an interosseous membrane, allowing no significant movement.

Tarsus

The ankle complex formed by 7 tarsal bones: talus, calcaneus, cuboid, navicular, lateral cuneiform, intermediate cuneiform, and medial cuneiform.

Talus

A large weight-bearing tarsal bone that articulates superiorly with the inferior articular surface of the tibia.

Calcaneus

The largest tarsal bone that forms the heel and bears substantial body weight.

Metatarsals

The 5 foot bones numbered 1 through 5 starting medially; bones 1–3 articulate with the cuneiforms and bones 4–5 articulate with the cuboid.

Hallux

The great toe; features only 2 phalanges (proximal and distal), while digits 2 through 5 each possess 3 phalanges (proximal, middle, distal).