UPPER LIMB BONES — FULL SUMMARY
Includes:
Pectoral girdle → Clavicle, Scapula
Arm → Humerus
Forearm → Radius, Ulna
Hand → Carpals, Metacarpals, Phalanges
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I. CLAVICLE (Collarbone)
Type: S-shaped long bone
Articulations:
Medially with sternum (SC joint)
Laterally with acromion (AC joint)
Features
Medial 2/3: convex forward
Lateral 1/3: concave forward
Inferior surface:
Conoid tubercle (conoid ligament)
Trapezoid line (trapezoid ligament)
Superior surface smooth
Clinical
Most commonly fractured bone
Fracture → SCM pulls medial fragment superiorly
Subclavian vessels lie below (protected by subclavius)
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II. SCAPULA (Shoulder blade)
Triangular bone over ribs 2–7
Anterior features
Subscapular fossa
Coracoid process
Glenoid cavity
Supraglenoid tubercle (long head of biceps origin)
Infraglenoid tubercle (long head of triceps origin)
Posterior features
Spine of scapula
Acromion
Supraspinous fossa
Infraspinous fossa
Borders
Superior
Lateral
Medial
Angles
Superior, Inferior, Lateral (glenoid)
Clinical
Winged scapula → Long thoracic nerve injury
Fractures uncommon (protected by muscles)
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III. HUMERUS (ARM BONE)
⭐ UPPER END
Head (faces medially)
Anatomical neck
Surgical neck (common fracture → axillary nerve injury)
Greater & lesser tubercles
Intertubercular sulcus (bicipital groove)
Nerve relations:
Surgical neck → axillary nerve
Radial groove → radial nerve
Medial epicondyle → ulnar nerve
⭐ SHAFT
Deltoid tuberosity
Radial (spiral) groove
⭐ LOWER END
Condyles:
Capitulum (articulates with radius)
Trochlea (with ulna)
Epicondyles:
Medial epicondyle (ulnar nerve)
Lateral epicondyle
Fossae:
Coronoid fossa
Radial fossa
Olecranon fossa
Clinical
Supracondylar fracture → median nerve injury, brachial artery injury
Medial epicondyle fracture → ulnar nerve palsy
Mid-shaft fracture → radial nerve palsy, wrist drop
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IV. RADIUS (LATERAL FOREARM BONE)
Upper end
Head of radius (disc-shaped)
Neck
Radial tuberosity
Shaft
Interosseous border
Pronator teres insertion (midshaft lateral)
Lower end
Ulnar notch
Radial styloid process (extends more distally than ulnar)
Clinical
Colles fracture (distal radius) → “dinner fork deformity”
Smith fracture (reverse Colles)
Radial head subluxation in children (nursemaid’s elbow)
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V. ULNA (MEDIAL FOREARM BONE)
Upper end
Olecranon process
Coronoid process
Trochlear notch
Ulnar tuberosity
Shaft
Interosseous border
Attachment for FDS, FDP, pronator quadratus
Lower end
Head of ulna
Ulnar styloid process
Clinical
Olecranon fracture
Monteggia fracture → ulna fracture + radial head dislocation
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VI. CARPAL BONES (WRIST)
Proximal row (lateral → medial):
Scaphoid
Lunate
Triquetrum
Pisiform
Distal row (lateral → medial):
Trapezium
Trapezoid
Capitate
Hamate
Clinical
Scaphoid fracture → avascular necrosis (pain in anatomical snuffbox)