Chapter 8.2 - Appendicular Skeleton

Flashcards covering the appendicular skeleton, including bones of the upper and lower limbs, girdles, and development.

Appendicular Skeleton

The 126 bones primarily involved in body movements, acting as appendages to the central skeleton, including upper and lower limbs and their girdles.

Pectoral Girdle

Also known as the shoulder girdle, it supports the arm and consists of the clavicle (collarbone) and scapula (shoulder blade) on each side of the body.

Sternoclavicular Joint

The articulation between the clavicle and the sternum.

Acromioclavicular Joint

The articulation between the clavicle and the scapula.

Glenohumeral Joint

The shoulder joint where the scapula articulates with the humerus; easily dislocated due to its loose attachment.

Clavicle

S-shaped bone that braces the shoulder and keeps the arm away from the midline; frequently fractured.

Conoid Tubercle

Rough bump near the acromial end of the clavicle.

Scapula

Triangular plate that posteriorly overlies ribs 2 to 7, resembling a shovel.

Suprascapular Notch

Conspicuous notch on the superior border of the scapula, providing passage for a nerve.

Scapular Spine

Transverse ridge on the posterior surface of the scapula.

Supraspinous Fossa

Indentation superior to the spine on the scapula.

Infraspinous Fossa

Broad surface inferior to the spine on the scapula.

Subscapular Fossa

Concave, anterior surface of the scapula.

Acromion

Plate-like extension of the scapular spine that forms the apex of the shoulder and articulates with the clavicle.

Coracoid Process

Shaped like a bent finger, it provides attachment for tendons of the biceps brachii and other arm muscles.

Glenoid Cavity

Shallow socket on the scapula that articulates with the head of the humerus, forming the glenohumeral joint.

Upper Limb Regions

Brachium (arm), Antebrachium (forearm), Carpal region (wrist), Metacarpals (palm), and Phalanges (fingers).

Humerus

Bone of the brachium (arm), extending from shoulder to elbow.

Radius and Ulna

Bones of the antebrachium (forearm), extending from elbow to wrist.

Carpals

Eight small bones arranged in two rows in the carpal region (wrist).

Metacarpals

Five bones in the palm of the hand.

Phalanges (Hand)

Fourteen bones in the fingers.

Head of Humerus

Hemispherical part of the humerus that articulates with the glenoid cavity of the scapula.

Anatomical Neck

Region around the head of the humerus.

Greater and Lesser Tubercles

Found on the proximal end of the humerus for muscle attachment.

Deltoid Tuberosity

Area on the humerus for attachment of the deltoid muscle.

Intertubercular Sulcus

Holds the biceps tendon on the humerus.

Surgical Neck

Distal to the tubercles on the humerus, a common fracture site.

Capitulum

Rounded structure on the distal end of the humerus that articulates with the head of the radius.

Trochlea

Articulates with ulna on the humerus.

Lateral and Medial Epicondyles

Distal features of the humerus.

Olecranon Fossa

Holds olecranon process of ulna on the humerus.

Coronoid Fossa

Located on the distal humerus.

Radial Fossa

Located on the distal humerus.

Radius

Bone in the antebrachium that allows for rotation during pronation and supination.

Head of Radius

Disc-shaped and allows for rotation during pronation and supination.

Radial Tuberosity

Attachment for the biceps muscle on the radius.

Styloid Process (Radius)

Can be palpated near the thumb on the radius.

Ulnar Notch

Accommodates the head of the ulna.

Ulna

Bone in the antebrachium with the trochlear notch.

Trochlear Notch

Articulates with the trochlea of the humerus on the ulna.

Olecranon

Bony point at the back of the elbow on the ulna.

Coronoid Process (Ulna)

Located on the ulna.

Radial Notch

Holds the head of the radius on the ulna.

Styloid Process (Ulna)

Located on the ulna.

Interosseous Membrane

Ligament that attaches the radius to the ulna along the interosseous margin of each bone.

Carpal Bones

Eight bones that form the wrist, allowing movements of flexion, extension, abduction, and adduction.

Proximal Row of Carpal Bones

Scaphoid, lunate, triquetrum, and pisiform.

Distal Row of Carpal Bones

Trapezium, trapezoid, capitate, and hamate.

Metacarpals

Bones of the palm.

Phalanges (Fingers)

Bones of the fingers.

Pollex

Thumb has two phalanges: proximal and distal.

Fingers

Have three phalanges: proximal, middle, and distal.

Pelvic Girdle

Made up of two hip bones (os coxa, coxal bones) that articulate with the sacrum posteriorly. Each hip bone is made up of the ilium, ischium, and pubis.

Pubic Symphysis

The articulation where the two pubic bones meet anteriorly, with a disc of fibrocartilage between them.

Pelvis

The pelvic girdle plus ligaments and muscles that line the pelvic cavity and form its floor.

Sacroiliac Joint

The joint where the coxal bone joins the vertebral column (auricular surface of ileum to auricular surface of sacrum).

Greater (False) Pelvis

Between the flare of the hips.

Lesser (True) Pelvis

Narrower and below the pelvic brim.

Pelvic Brim

Round margin that separates the greater and lesser pelvis.

Pelvic Inlet

Opening circumscribed by the pelvic brim that an infant’s head must pass during birth.

Pelvic Outlet

Lower margin of the lesser pelvis.

Iliac Crest

Superior crest of the hip bone.

Acetabulum

Hip socket.

Obturator Foramen

Large hole below the acetabulum.

Ilium

Largest bone in the hip extending from the iliac crest to the center of the acetabulum.

Ischium

Inferior-posterior portion of the hip.

Pubis

Most anterior portion of the hip bone.

Sex Differences in Pelvis

Male: heavier and thicker. Female: wider and shallower, larger pelvic inlet and outlet for passage of infant’s head; adapted to the needs of pregnancy and childbirth.

Lower Limb Regions

Thigh (femoral region), leg proper (crural region), foot (tarsal and metatarsal regions), and toes (digits).

Femur

Longest and strongest bone of the body, located in the thigh.

Patella

Located in the thigh.

Tibia and Fibula

Located in the leg proper.

Metatarsals

Located in the foot.

Phalanges (Toes)

Located in the toes.

Head of Femur

Hemispherical head that articulates with the acetabulum of the pelvis.

Fovea Capitis

Pit in the head of the femur for attachment of a ligament.

Greater and Lesser Trochanters

For muscle attachment on the femur.

Intertrochanteric Crest

Thick ridge on the posterior surface of the femur that connects the trochanters.

Intertrochanteric Line

More delicate ridge on the anterior surface of the femur that connects the trochanters.

Linea Aspera

Ridge on the posterior portion of the shaft of the femur.

Femoral Condyles and Epicondyles

Medial and lateral found distally.

Patella

Triangular sesamoid bone embedded in the tendon of the knee.

Base of Patella

Broad, superior portion.

Apex of Patella

Pointed, inferior portion.

Articular Facets

Shallow, posterior portion of the patella.

Tibia

Thick, medial, weight-bearing bone of the leg.

Fibula

Slender, lateral strut that helps stabilize the ankle but does not bear any body weight.

Medial and Lateral Condyles (Tibia)

Flat surfaces that articulate with the condyles of the femur.

Tibial Tuberosity

Attachment of patellar ligament on the tibia.

Medial Malleolus

Bony knob on the inside of the ankle on the tibia.

Lateral Malleolus

Distal expansion, bony knob on the lateral side of the ankle on the fibula.

Tarsal Bones

In the ankle, differing from carpal bones due to the load-bearing role of the ankle.

Calcaneus

Largest tarsal bone that forms the heel; distal portion is the point of attachment for the calcaneal (Achilles) tendon.

Talus

Most superior tarsal bone that forms the talocrural joint with the tibia and fibula.

Proximal Row of Tarsal Bones

Talus, calcaneus, and navicular.

Distal Row of Tarsal Bones

Medial, intermediate, and lateral cuneiforms and cuboid.

Metatarsals

Located in the foot; Metatarsal I is proximal to the great toe (hallux), and Metatarsal V is proximal to the little toe.

Phalanges (Toes)

Two in the great toe (proximal and distal), three in all other toes (proximal, middle, and distal).

Arches of the Foot

Three arches supported by ligaments and tendons (Medial Longitudinal Arch, Lateral Longitudinal Arch, and Transverse Arch) that allow the foot to support the body's weight.