A&P Lab 2: Appendicular Skeleton

Parts of Appendicular Skeleton

pectoral girdle

• upper limb: arm (brachium) and forearm (antebrachium)

• upper limb: wrist and hand

• pelvic girdle

• lower limb: thigh and leg

• lower limb: ankle and foot

Pectoral Girdle contains

Clavicle and Scapula

Sternal End

Has a rough pyramid shape and articulates with the manubrium of the sternum

Acromial End

flat shape and articulates with the acromion of the scapula

Trapezoid ridge and conoid tubercle

located on the inferior side on the right clavicle. These are the sites of conoid and trapezoid ligament attachments that connect the clavicle to the scapula

Clavicle Fracture

Happens frequently, common in children, caused by indirect force from outstretched hand, weakest part

Anterior and posterior surfaces of scapula are called

Costal and dorsal sides

Scapula three edges

medial, lateral, superior borders

Scapula three points

superior, inferior, and lateral angles

Costal side of scapula contains the

Subscapular fossa

Subscapular fossa

broad surface on anterior side of scapulae. The subscapularis muscle covers this fossa

Acromion

a large posterior process that forms the bony shoulder tip, continuous with the spine

Coracoid Process

Smaller, anterior projection

Spine of scalpula

Ridge of bone on the posterior aspect of scapula

Supraspinous Fossa

the region of the scapula immediately superior to the scapular spine. The supraspinatus muscle is located here.

Infraspinous fossa

the region of the scapula immediately inferior to the scapular spine. The

infraspinatus muscle is located here.

Glenoid Cavity

found at a lateral angle, shallow cavity (cup-shaped) that articulates with the humerus

Upper limb bones

Humerus, radius, ulna

Head of humerus

the proximal epiphysis that fits into the glenoid cavity. This ball-like structure helps form the glenohumeral joint.

Anatomical Neck

Inferior and encircling the head where the proximal epiphysis (head) joins the diaphysis.

Greater tubercle

projection lateral to the anatomical neck

Lesser Tubercle

projection located inferior to the anatomical neck

Intertubercular sulcus or bicipital groove

depression located between the greater and lesser tubercle. Contains the tendon the long head of the biceps brachii muscle.

Surgical Neck

located distal to the greater and lesser tubercles at a narrowing in the diaphysis. Common site of fractures.

Shaft

Diaphysis area of humerus

Radial Groove

radial nerve and blood vessels pass through the groove

Deltoid tuberosity

on the lateral side halfway down the humerus; the deltoid muscle attaches here

Capitulum

rounded “little head”, articulates with the head of the radius

Trochlea

pulley-like structure, that is medial to the capitulum. Articulates with the trochlear notch of the ulna

Coronoid Fossa

depression right above the trochlea; accommodates coronoid process of the ulna

Medial Epicondyle

a more prominent bump on the medial side of the humerus. The ulnar nerve (i.e., the “funny bone”) can be stimulated by pressing the arm posterior to the medial epicondyle

Lateral Epicondyle

less prominent bump on the lateral side of the humerus

Olecranon Fossa

larger cavity on the posterior side of the humerus (distal end). Accommodates the olecranon of the ulna during extension of the elbow.

Ulna and Radius

Bones of forearm

Medial side of forearm (side of pinky finger)

Ulna location

Trochlear notch

The ulna's C-shaped proximal end

Coronoid process

the anterior-most tip of the trochlear notch, goes into the coronoid fossa of the humerus

Olecranon Process

posterior side of the ulna; ‘Point of the elbow’

Styloid process of ulna

on the distal end of the ulna

Laterally placed, on the same side as thumb

Radius location

Radial Head

disc-shaped head that articulates with the capitulum of the humerus

Radial neck

narrow structure between head and shaft

Radial tuberosity

medial projection (bump) on the distal head of the radius

Radial styloid process

bony projection on the distal end of radius

Carpal bones

8 bones, allows for multiple movements of the wrist

Carpal bone mneumonic device

Straight Line To Pinky, Here Comes The Thumb

Scaphoid Fracture

• The most frequently fractured carpal bone is scaphoid

• Often results from a fall on the palm

• Often misdiagnosed early

Carpal Tunnel Syndrome

• Anterior concave space formed by carpal bones and soft tissue structures

• What passes through here: Tendons (9 total) & tendon sheaths of flexor muscles & the median nerve

• A reduction of the size of the carpal tunnel or increasing in the size of the structure within the tunnel

• Median n. compression can cause paresthesias (tingling)

Metacarpals

• 5

• Bones of the palm of the hand

• Articulate with distal row of carpal bones and phalanges

• Roman numerals I-V are used to identify bones, I is the thumb, V is the little finger

Phalanges number

14

Proximal Phalanx

articulates with the head of the metacarpal

Distal Phalanx

At tip of finger

Middle phalanx

between proximal and distal phalanges

Thumb phalange number

2

• Support body weight

• Used for locomotion

• Maintain balance

Lower limb bones purpose

o Pelvic Girdle

o Thigh (femoral)

o Leg (crural)

o Foot

Lower limb bone regions

Left and right coxal bones

Make up the pelvic

Ilium, ischium, and pubis

Bones of the coxal bone

Acetabulum

a deep socket where the hip articulates with the head of the femur.

Obturator Foramen

space in os coxae, encircled by public and ischial rami

Ilium

Largest bone of hip, resembles elephant ears

Greater Sciatic notch

another structure that can be seen near the posterior inferior iliac spine. This is where the sciatic nerve will exit.

Iliac crest

Outer edge of ilium

Iliac spine

On the most anterior point of the iliac crest is a prominent projection called the anterior superior and inferior iliac spine and on the posterior point of the iliac crest are, the posterior superior and inferior iliac spines. These projections are important sites of attachment for thigh muscles

Ala

fan-shaped structure on the medial surface of ilium

Ischium

Forms bony lower portion of pelvis

Ischial Tuberosity

the most prominent feature of the ischium, often referred to as our "sit bones." Bears weight of the body in a sitting position.

Ischial Ramus

anterior to the ischial tuberosity, contributes to obturator foramen.

Ischial Spine

Triangular (point-like) structure posterior to the acetabulum.

Lesser sciatic notch

semicircular depression inferior to ischial spine

Pubic bones

Form the anterior and inferior portions of the pelvis

Pubis symphysis

the pubic bones meet here.

Pubic body

Thickest and most anterior portion of the bone

Pubic ramus

from the pubic body are two extending rods of bone; a superior pubic ramus and an inferior pubic ramus.

femur, patella, tibia, and fibula, as well as the bones of the foot.

Lower limb bones

Femur

Thigh’s only bone

Head

The proximal portion of the femur, articulates with the acetabulum of the coxal bone

Fovea Capitis

on the middle of the head of the femur is a pit, where a ligament connects the head to the acetabulum

Neck

Attaching the head of the femur to the rest of the bone

Linea Aspera

on the posterior side of the shaft, a raised feature runs the bone's length.

Greater trochanter

immediately distal to the neck. Laterally placed on femur and attachment side for gluteus medius and minimus muscles

Lesser trochanter

on femur’s posteromedial surface, gluteus muscle attachment site

Intertrochanteric Line

on the posterior side of the bone, travels between trochanters

Diaphysis of femur

Shaft of the femur

Nutriuent foramina of femur

in the middle of the linea aspera, the entrance area of the nutrient artery that supplies the femur

Medial condyle

oval structure on the medial, proximal end of the femur, articulates with medial condyle on the tibia

Lateral Condyle

oval structure on the posterior, lateral side, at the proximal end of the femur, articulates with lateral condyle on the tibia

Medial and lateral epicondyle

Superior to each condyle

Intercondylar Fossa

groove between condyles on the posterior side of the femur

Patellar Surface

smooth depression on the anterior surface. The patella articulates with it.

Patella

• Kneecap

• Large, triangular sesamoid bone

• Housed within the tendon of the quadriceps femoris muscle

• Allows tendon to glide more smoothly

• Protects knee joint

• Superior broad base

• Inferior pointed apex

• The articular surface on the posterior aspect

o Articulates with the patella surface of the femur

Tibia and Fibula

Compose lower leg

Medial and lateral condyle

flat surface on the proximal end of the tibia on the superior head

Intercondylar Eminence

separates medial and lateral condyles

Tibial tuberosity

on the anterior surface of the tibia, near the proximal condyle

Medial malleolus

large process near the distal end of the anterior crest curves. Palpated on the medial side of the ankle.

Head

knoblike structure posterior and inferior to tibia’s lateral condyle

Neck and shaft

Part of bone distal to the head

Lateral malleolus

extends laterally to the ankle joint, palpated on the lateral side of the ankle.

Fibular notch

at the distal lateral end of the tibia, where the fibula articulates with the tibia.