Appendicular Skeleton

Clavicle

Collarbone; S-shaped bone connecting sternum to scapula. Medial end = sternal, lateral end = acromial. Helps stabilize shoulder. 

Scapula

Flat, triangular shoulder blade bone. Features: spine, acromion, coracoid process, glenoid cavity, supraspinous & infraspinous fossae.

Humerus

Arm bone between shoulder & elbow. Features: head, anatomical/surgical neck, tubercles, deltoid tuberosity, condyles, fossae.

Radius

Forearm bone on thumb side. Features: head (disc-shaped), radial tuberosity, styloid process.

Ulna

Forearm bone on pinky side. Features: olecranon, coronoid process, trochlear notch, styloid process.

Carpals

8 wrist bones arranged in two rows. Provide flexibility. 

Metacarpals

5 long bones of the palm, numbered I–V (thumb = I → pinky = V). Form knuckles at their heads.

Phalanges

Finger bones. Each digit has proximal, middle, and distal phalanges, except the thumb (only proximal & distal).

Ilium

Superior portion of hip bone. Features: iliac crest, ASIS, PSIS, iliac fossa, greater sciatic notch.

Ischium

Posterior, inferior hip bone. Features: ischial spine, tuberosity, ramus.

Pubis

Anterior hip bone. Features: pubic symphysis, pubic tubercle, superior/inferior rami.

Acetabulum

Deep socket where ilium, ischium, and pubis fuse. Articulates with femoral head.

Obturator Foramen

Large opening formed by pubis & ischium, mostly closed by connective tissue.

Femur

Thigh bone, longest in body. Features: head, fovea capitis, trochanters, condyles, epicondyles, patellar surface.

Patella

Kneecap; sesamoid bone in quadriceps tendon. Apex points downward.

Tibia

Medial shin bone. Features: condyles, tibial tuberosity, anterior crest, medial malleolus.

Fibula

Lateral shin bone. Features: head, shaft, lateral malleolus.

Tarsals

7 ankle bones. Major ones: talus (ankle joint), calcaneus (heel).

Foot metatarsals

5 long bones of the midfoot, numbered I–V (big toe = I → little toe = V). Form the arches of the foot.

Foot phalanges

Toe bones. Each digit has proximal, middle, and distal phalanges, except the big toe (only proximal & distal).

Synarthrosis fibrous joint

Immovable joints, e.g., sutures of the skull.

Amphiarthrosis Cartilaginous Joint

Slightly movable joints, e.g., pubic symphysis.

Diarthrosis Synovial Joint

Freely movable joints. Includes 6 subtypes.

Planar Joint

Flat surfaces glide; ex: intercarpal joints.

Hinge Joint

Flexion/extension only; ex: elbow, knee.

Pivot joint

Rotation around axis; ex: proximal radioulnar.

Condylar Joint

Oval surface fits into depression; ex: wrist.

Saddle joint

Concave/convex surfaces; ex: thumb CMC joint.

Ball-and-Socket Joint

Spherical head into cup; ex: shoulder, hip.