Lab hand 2

Upper Extremity Bones

• Clavicle

  • Known as the collarbone.

  • Key features:

    • Sternal End: The flat end that attaches to the sternum.

    • Acromial End: The curved end.

  • Important not to confuse clavicle with ribs (clavicle is shorter).

• Sternum

  • The sternum consists of three parts:

    • Manubrium: The top portion.

    • Body: The middle plate.

    • Xiphoid Process: The small part at the bottom.

  • Jugular Notch: Located at the top where the manubrium is.

• Ribs

  • Ribs encircle the chest from front to back.

  • Articulate with both the sternum and vertebrae.

  • Types of ribs:

    • True Ribs (1-7): Attach directly to the sternum.

    • False Ribs (8-10): Attach indirectly to the sternum.

    • Floating Ribs (11-12): Do not attach to the sternum.

• Scapula

  • Also known as the wing bone.

  • Key features:

    • Spine of the Scapula: The prominent ridge.

    • Supraspinous Fossa: Above the spine, where supraspinatus muscle attaches.

    • Infraspinous Fossa: Below the spine.

    • Coracoid Process: A small hook-like structure near the shoulder.

    • Acromion: Larger structure at the end of the spine, meeting the clavicle.

    • Borders: Medial (straighter) and lateral (angled).

• Humerus

  • Long bone of the upper arm.

  • Important landmarks:

    • Head: Joins with the scapula to form the shoulder joint.

    • Greater and Lesser Tubercle: Projections for muscle attachment.

    • Deltoid Tuberosity: A raised area for the deltoid muscle attachment.

    • Medial and Lateral Epicondyles: Important for tendon attachment.

    • Coronoid Fossa: For articulation with the coronoid process of the ulna.

    • Olecranon Fossa: Located at the back of the distal end, where the elbow fits.

• Radius and Ulna

  • Radius: Located on the thumb side of the forearm.

    • Head: Articulates with the humerus.

    • Neck: Just below the head.

    • Radial Tuberosity: For muscle attachment.

    • Styloid Process: Prominent projection on the wrist side.

  • Ulna: Located on the pinky side of the forearm.

    • Olecranon: Forms the elbow.

    • Trochlear Notch: C-shaped indentation for the humerus.

    • Ulnar Tuberosity: A raised area for attachment.

    • Styloid Process: Located at the wrist end, noticeable near pinky.

  • The interosseous membrane connects the radius and ulna.

• Hand

  • Metacarpals: Five bones numbered I-V (thumb to pinky).

  • Phalanges: Bones of the fingers:

    • Proximal: First segment; closest to hand.

    • Middle: Second segment; absent in the thumb.

    • Distal: Final segment; farthest from the hand.

  • Joints: Metacarpophalangeal joints articulate with the phalanges.