BIO65 || CH8: Appendicular Skeleton

Identify and describe the features of the clavicle, scapula, humerus, radius, ulna, and bones of the wrist and hand.

• Clavicle

  • Collarbone

  • S-shaped bone

  • Easily palpated

  • Braces the shoulder

  • Most commonly fractured bone (especially during childbirth)

• Scapula

  • Anterior View

    • Shoulder blade

    • Contains superior, medial, lateral borders

    • Acromion - articulates with clavicle 

    • Coracoid process - for biceps attachments

    • Glenoid cavity - socket for humerus

    • Subscapular fossa

  • Posterior view

    • Overlies ribs 2-7

    • Superior, inferior, lateral angles

    • Spine - ridge on posterior surface

      • Ends in the acromion at its apex

    • Division between

      • Supraspinous fossa

      • Infraspinous fossa

• Humerus

  • Proximal end

    • Head for glenoid fossa/cavity

    • Intertubercular sulcus for biceps’ tendon

    • Greater tubercle

    • Lesser tubercle

    • Anatomical vs Surgical neck

    • Deltoid tuberosity

  • Distal end

    • Capitulum for radius

    • Trochlea for ulna

    • Radial fossa

    • Coronoid fossa

      • For coronoid process on the ulna

    • Olecranon fossa

      • Deep posterior pit (for elbow hinge joint)

    • Medial/lateral epicondyles

• Radius

  • Proximal end (elbow region)

    • Radius has disc-shaped head to articulate with the capitulum of humerus

    • Neck of the radius

    • Radial tuberosity

    • Interosseus border and membrane

• Ulna

  • Proximal ends (elbow region)

    • Ulna has olecranon, trochlear notch, and coronoid process for articulation with the humerus

    • Ulna has radial notch for head of radius to spin

    • Ulnar tuberosity

    • Interosseus border and membrane

• Radius and Ulna

  • Distal End (wrist region)

    • Ulna has a round head with a styloid process

    • Radius also has a styloid process

    • Radius has an ulnar notch for the head of the ulna

• Carpals

  • The carpals consist of 2 rows of 4 small bones

  • Proximal (closest to radius/ulna) row: Scaphoid, Lunate, Triquetrum, Pisiform

  • Distal (closest to hand) row: Hamate, Capitate, Trapezoid, Trapezium

• Metacarpals

  • Bones of palm

    • 1: base of thumb

    • 5: base of little finger

    • Base: proximal end

    • Body: shaft

    • Head: distal end

      • Form your knuckles

• Phalanges

  • Bones of the fingers

    • 1: pollex (thumb)

      • 2 bones

        • Proximal

        • Distal

    • 2-5: digits

      • 3 bones 

        • Proximal

        • Middle

        • Distal

Identify and describe the features of the pelvic girdle, femur, patella, tibia, fibula, and bones of the foot.

• The Pelvic (Hip) Girdle

  • Girdle = 2 hip (coxal) bones + sacrum

  • 3 bones - Ilium, Ischium, Pubis

    • Fuse by age 26

  • Contains 2 joints

  • Sacroiliac (SI) joints

    • Pubic symphysis

    • Right Hip Bone 

  • Lateral View

    • Ilium

      • Iliac crest

      • Iliac spines (4)

      • Greater sciatic notch

    • Ischium

      • Ischial tuberosity

      • Ischial rami

      • Ischial spine

    • Pubis

      • Superior/inferior pubic rami

      • Body

    • Acetabulum

      • Hip socket

    • Obturator foramen

  • Medial View

    • Ilium

      • Iliac crest

      • Iliac spines (4)

      • Greater sciatic notch

      • Iliac fossa

    • Auricular surface

    • Ischium

      • Ischial rami

      • Ischial spine

    • Pubis

      • Pubic symphysis

    • Obturator foramen

• Femur

  • The femur of the thigh is the longest, heaviest, and strongest bone in the body

  • Proximal end

    • Head

      • Fovea capitis

    • Greater/lesser trochanters

    • Intertrochanteric crest (posterior) and line (anterior)

    • Neck

    • Shaft

      • Linea aspera

  • Distal end

    • Lateral and medial epicondyles

    • Lateral and medial condyles

    • Intercondylar fossa

    • Patellar surface for patella

• Patella

  • The largest sesamoid bone in the body

  • Patella - kneecap

    • Inferior apex

    • Base of patella

  • Tibia and Fibula

  • The lower leg consists of the tibia (shinbone) and the fibula (does not bear weight)

  • The tibia’s proximal end articulates with the femur and its distal end with the talus bone of the ankle

    • The tibial tuberosity on the anterior surface is the point of attachment for the patellar ligament

    • Clinical: bc the fibula is not a weight-bearing bone, it is a good source for bone grafting

• Tibia

  • Proximal end

    • Medial and lateral condyles

    • Intercondylar eminence

    • Tibial tuberosity

  • Shaft of tibia (shin)

    • Anterior border

  • Distal end

    • Medial malleolus

• Fibula

  • Proximal end

    • Apex

    • Head

  • Distal end

    • Lateral malleolus

• Tarsals

  • Talus - most superior

  • Calcaneus (heel)

  • Navicular

  • Medial, Intermediate, Lateral Cuneiforms

  • Cuboid

• Metatarsals

  • Numbered, 1-5, medial to lateral

• Phalanges (same idea as for the fingers)

  • Bones of toes

  • Great toe (hallux)

    • 2 phalanges - proximal/distal (just like the thumb)

  • 3 bones in all others

    • 2-5

    • Proximal, middle, distal (just like the fingers)

Compare the anatomy of the male and female pelvic girdles and explain the functional significance of the differences.

• Males

  • More robust

  • Narrower

  • Deeper

  • Narrow subpubic angle (<90 degrees)

  • Smaller pelvic inlet and outlet

• Females

  • Adapted to childbirth

  • Wider

  • Shallower

  • Wide subpubic angle (>90 degrees)

  • Larger pelvic inlet and outlet

Describe some common disorders of the appendicular skeleton.

• Scoliosis

  • Abnormal lateral curvature

• Hyperkyphosis

  • Abnormal posterior thoracic curvature

• Hyperlordosis

  • Swayback

  • Abnormal anterior lumbar curvature