Upper Limb Bones

Bones of Upper Extremity

Basic Identification of Bones & X-Rays

The upper extremity consists of numerous bones that facilitate movement and structural support. X-rays are crucial for visual identification and understanding the arrangement of these bones.

Outline of Bones of Upper Extremity

  • Pectoral Girdle (Right): Comprises the

    • Scapula

    • Clavicle

  • Free Part of Upper Limb (Right): Includes the following bones:

    • Humerus

    • Ulna

    • Radius

    • Carpals

    • Metacarpals (I–V)

  • Phalanges (Posterior View): Various finger bones

  • Manubrium of Sternum: Connects with the clavicle

Specific Regions and Bone Count

Pectoral Girdle

  • 1 Clavicle

  • 1 Scapula

Arm (Brachial Region)

  • 1 Humerus

Forearm (Antebrachial)

  • 1 Radius

  • 1 Ulna

Hand

  • 8 Carpals

  • 5 Metacarpals

  • 14 Phalanges

Clavicle Anatomy (Right)

The clavicle has several key areas:

  • Medial Sternal End: Connects with manubrium of sternum

  • Lateral Acromial End: Connects with shoulder

  • Views include:

    • Superior

    • Inferior

Scapula Anatomy and Features

  • Acromion: Partial attachment for Trapezius & Deltoid muscles

  • Coracoid Process: Resembles a raven's beak, attachment for muscles

  • Glenoid Cavity: Socket for humeral head; is the shoulder joint

  • Spine: Serves as another attachment point for muscles

  • Major fossae include:

    • Supraspinous Fossa

    • Infraspinous Fossa

    • Subscapular Fossa

Specific Features of Scapula

  • Spine of Scapula: Partial attachment for larger muscles

  • Glenoid Cavity articulation allows for joint movement

  • Acromion aids in articulation with the humerus

  • Fossae support muscle attachments including Supraspinatus and Infraspinatus

Humerus Structure Overview

Proximal Humerus

  • Head: Articulates with glenoid cavity of scapula

  • Surgical Neck: More prone to fracture than anatomical neck

  • Greater/Lesser Tubercle: Sites for muscle attachment, significant for rotator cuff

  • Intertubercular Sulcus: Passage for tendon of biceps brachii muscle

Distal Humerus

  • Capitulum: Articulates with the head of the radius

  • Trochlea: Pivotal point articulating with ulna

  • Lateral/Medial Epicondyles: Muscle attachment points for forearm

Radius & Ulna Overview

Proximal Radius & Ulna

  • Head: Articulates with capitulum, aiding in mobility

  • Neck: Supports radial tuberosity

  • Coronoid Process & Trochlear Notch: Stabilizes forearm movement

Distal Radius & Ulna

  • Radial Styloid Process: Stability and muscle attachment for wrist

  • Head of Ulna: Another articulating surface

  • Ulnar Styloid Process: Similar to radial counterpart, provides ligament attachment

Hand Anatomy Overview

Phalanges and Metacarpals

  • Phalanges: Classified into Distal, Middle, and Proximal sections

  • Metacarpals (I-V): Form the palm, with digit 1 having fewer bones

  • Carpals: Two rows consisting of Scaphoid, Lunate, Triquetrum, Pisiform, Trapezium, Trapezoid, Capitate, and Hamate; arranged from lateral to medial

Checkpoints for Knowledge Application

These checkpoints aim to reinforce learning and ensure comprehension of the anatomical structures and their significance in upper extremity anatomy.