Cram!!

Appendicular Skeleton

Division of the skeleton responsible primarily for movement; includes upper and lower limbs and their girdles.

Pectoral Girdle

A bony ring that functions as your shoulder, consisting of the clavicle (collar bone) and the scapula (shoulder blade), which are attached by the upper limb of the axial skeleton.

Pectoral Girdle: Function

• Structural Support: Attaches the bones of the upper limb to the axial skeleton.

• Muscle Attachment: Serves as an anchoring point for the muscle tendons and ligaments.

• Mobility: Allows the upper limb to move in various directions without any limitations.

Clavicle

S-shaped bone that connects the upper limb to the sternum, known as the collarbone.

Clavicle: Function

• Structural Support: Holds the pectoral girdle away to allow the arm to move freely from the shoulder joints.

• Force Transmission: Can safely route mechanical forces and weight from the upper limb to the axial skeleton for movement.

• Protection: Shields nerves and blood vessels when traveling between the axial skeleton and the upper limb.

Sternal End

Medial end that articulates with the manubrium of the sternum.

Sternoclavicular Joint

The joint connects the clavicle to the sternum through the sternal end of the clavicle.

Acromial End

Lateral end that articulates with the acromion of the scapula.

Acromioclavicular Joint

The joint connects the clavicle to the acromion of the scapula through the acromial end of the clavicle.

Conoid Tubercle

On the inferior-lateral end that attaches for the conoid ligament on the clavicle, in which attaches the clavicle and scapula

Costoclavicular Ligament

A band of connective tissue that attaches both the clavicle and scapula to the first rib.

Scapula

A triangular flat bone on the posterior thorax (lower back), known as the shoulder blade

Scapula: Function

• Mobility: Allows the shoulder to pivot and point in multiple directions for a full range of motion.

• Structural Support: Provides a stable base that allows the humerus (upper arm bone) to move without dislocation.

• Muscle Attachment: Anchors different kinds of muscles that provide strength and leverage to move the arm.

Acromion

Extension of the scapular spine that forms the highest point of the shoulder on the lateral end.

Spine

A long prominent ridge runs diagonally across the posterior surface of the scapula

Supraspinous Fossa

Posterior depression superior to the spine of the scapula as the attachment site for supraspinatus muscle.

Infraspinous Fossa

Posterior depression inferior to the spine of the scapula as the attachment site for infraspinatus muscle.

Subscapular Fossa

Anterior depression of the scapula as the attachment site for subscapularis muscle.

Superior Border

The upper edge of the scapula.

Suprascapular Notch

A prominent indentation on the superior border of the scapula for the passage of suprascapular nerve

Medial (Vertebral) Border

The thin edge of the scapula closest to the vertebral column.

Superior Angle

The point where the superior border and medial border meet.

Inferior Angle

The point where the medial border and the lateral border meet.

Lateral (Axillary) Border

The thick edge of the scapula closest to the arm.

Glenoid Cavity

A shallow depression that serves as an attachment site for the humerus from the glenohumeral (shoulder) joint

Glenohumeral Joint

A ball-and-socket joint connects the scapulae to the humerus through the glenoid cavity for arm rotation.

Humerus

Longest and largest bone of the upper limb that articulates proximally with the scapula and distally with the ulna and radius.

Head of Humerus

Proximal rounded portion that articulates with the glenoid cavity to form glenohumeral (shoulder) joint

Anatomical Neck

Groove distal to the head as the former growth plate.

Greater Tubercle

Lateral projection distal to the anatomical neck for muscle attachment.

Lesser Tubercle

Anterior projection on the anatomical neck for muscle attachment.

Intertubercular Sulcus

Groove between the greater and lesser tubercles.

Surgical Neck

A narrow, constricted section located just below the greater and lesser tubercles of the humerus, and are a common fracture site

Deltoid Tuberosity

Roughened, V-shaped area for attachment of the deltoid muscle.

Radial Groove

Groove on the posterior humerus that contains the radial nerve.

Capitulum

Lateral condyle of the humerus that articulates with the radius.

Radial Fossa

An anterior depression above the capitulum that receives the head of the radius during flexion

Trochlea

The medial knob-like condyle of the humerus articulates with the ulna.

Coronoid Fossa

An anterior depression that receives the coronoid process of the ulna during flexion.

Olecranon Fossa

A large posterior depression that receives the olecranon of the ulna during extension.

Medial Epicondyle

A rough attachment site for forearm muscles on the medial side.

Lateral Epicondyle

A rough attachment site for forearm muscles on the lateral side.

Ulna

Medial forearm bone located on the pinky side.

Olecranon

A thick, curved proximal projection forming the point of the elbow, acting as a lever for straightening the arm.

Coronoid Process

A thick, triangular, anterior projection of the ulna that articulates with the trochlea to form trochlear notch, acting as the hinge joint in the elbow.

Trochlear Notch

A large, C-shaped depression located at the proximal end of the ulna, formed by the olecranon and coronoid process.

Radial Notch

A depression on the lateral-inferior to the trochlear notch that attaches to the head of the radius for elbow function and forearm mobility

Ulnar Tuberosity

A rough, elevated prominence on the anterior-inferior to the coronoid process that attaches to the brachialis muscle

Styloid Process of Ulna

The posterior projection on the distal ulna end for collateral ligament attachment to the wrist.

Radius

The lateral forearm bone runs parallel to the ulna on the lateral (thumb) side of the forearm, and it runs narrow at the proximal end and widens at the distal end.

Head of Radius

A disc-shaped proximal end that articulates with the capitulum of the humerus and radial notch of the ulna.

Neck of Radius

The narrowed section of the radius bone located just beneath the disk-shaped radial head, connecting it to the radial shaft and tuberosity

Radial Tuberosity

A roughened area inferior to the neck of the radius that serves an attachment site for tendons of the biceps brachii muscle.

Styloid Process of Radius

The distal lateral projection under the thumb that attaches to the brachioradialis muscle and the radial collateral ligament to the wrist, or supports the lateral side of the wrist joint.

Ulnar Notch

The distal depression of the radius has a narrow concavity that articulates with the ulna at the distal radioulnar joint.

Interosseous Membrane

The first attachment site between the radius and ulna at a broad, flat, fibrous connective tissue that joins the two bones together to attach deep skeletal muscle.

Proximal Radioulnar Joint

A joint between the head of the radius and radial notch of the ulna, just below the elbow for forearm movement.

Distal Radioulnar Joint

A joint between the head of the ulna and the ulnar notch of the radius

Carpals

Eight wrist bones arranged in two rows (carpus) all joined into one through ligaments

_{Intercarpal Joints}

A complex series of synovial plane (gliding) joints that connect the eight carpal bones of the wrist together into two transverse rows of four.

Carpals: Proximal Rows

Articulates with the distal radius and ulna to form radiocarpal joint

Scaphoid

Most commonly fractured carpal bone.

Lunate

Moon-shaped carpal bone.

Triquetrum

Three-cornered carpal bone.

Pisiform

Pea-shaped carpal bone.

Radiocarpal (Wrist) Joint

A major synovial joint where the radius and ulna meet by the two carpus bone: lunate and scaphoid

Carpals: Distal Rows

Articulates with the metacarpals

Trapezium

Distal row carpal bone that articulates with the thumb.

Trapezoid

Distal row carpal bone between trapezium and capitate.

Capitate

Largest carpal bone.

Hamate

Carpal bone with a hook-shaped projection.

Carpal Tunnel

A narrow passageway containing flexor tendons and the median nerve in the wrist formed by carpal bones and the flexor retinaculum.

Ulnar Side of the Carpal Tunnel

The pisiform and hamate

Radial Side of the Carpal Tunnel

The scaphoid and trapezium.

Flexor Retinaculum

A strong fibrous band of connective tissue that forms the roof of the carpal tunnel.

Metacarpals

Five bones (metacarpus) form the palm, with bones numbered 1–5 from the thumb to pinky, and they are made up of three parts: a proximal base, an intermediate body, and a distal head

Metacarpals: Base

Articulates with the distal row of carpal bones through carpometacarpal joints

Metacarpals: Head

Articulates with the proximal phalanges through the metacarpophalangeal joints

Knuckles

Common name for the heads of the metacarpals.

Phalanges

Bones of the fingers and toes, with 14 bones (phalanx) in each hand and foot, are made up of the base, body, and head.

Phalanges: Digit Numbering

Digits are numbered 1–5, beginning with the thumb (lateral to medial).

Thumb (Pollex)

Thumb (Pollex) Has two phalanges: proximal and distal.

Digits 2–5

Have three phalanges: proximal, middle, and distal.

Interphalangeal Joints

Joints between phalanges.

Pelvic Girdle

Consists of the two hip bones, and connects lower limbs to the axial skeleton.

Pelvic Girdle: Function

• Weight Transfer: Supports the upper body’s weight and transfers it through the hip joints to the lower limbs

• Protection: Forms a pelvic cavity that houses and shields visceral organs

• Movement: Serves as an anchoring point for major muscle groups for walking, running, and balancing

Hip Bone

Coxal bone formed by fusion of the ilium, ischium, and pubis.

Pubic Symphysis

Fibrocartilaginous joint between the hip bones.

Bony Pelvis

A complete basin-shaped structure composed of the hip bones, pubic symphysis, sacrum, and coccyx that connect and support the spine to the lower limbs

Ilium

Largest and superior portion of the hip bone, composed of a superior ala and an inferior body.

Ala of the Ilium

The broad, wing-like superior portion of the ilium.

Body of the Ilium

The inferior portion of the ilium that contributes to the acetabulum.

Acetabulum

The socket of the hip bone that receives the head of the femur.

Iliac Crest

Superior border of the ilium.

Anterior Superior Iliac Spine (ASIS)

Anterior projection of the iliac crest.

Anterior Inferior Iliac Spine (AIIS)

Projection inferior to the ASIS.

Posterior Superior Iliac Spine (PSIS)

Posterior projection of the iliac crest.

Posterior Inferior Iliac Spine (PIIS)

Projection inferior to the PSIS.

Iliac Spines

Serve as attachment sites for tendons of the trunk, hip, and thigh muscles.

Greater Sciatic Notch

Passageway for the sciatic nerve, other nerves, blood vessels, and muscles