Upper Extremity Osteology

Question 1

Identify on Clavicle

• Sternal End
  
  • Sternal Facet (articulates with the Manubrium at the Clavicular Notch)
  • Impression for the Costoclavicular L. (small depression on inferior surface, attachment to Costoclavicular L. to the 1st Rib)
• Body (shaft)
  
  • Subclavian Groove (inferior surface, attachment point for the Subclavius M.)
• Acromial End
  
  • Acromial Facet (articulates with an Articular facet on the Acromion of the Scapula)
  • Conoid Tubercle (inferior surface, attachment point for the Conoid L.)
  • Trapezoid Line (inferior surface, attachment point for the Trapezoid L.)

Question 2

Identify on Scapula

• Borders
  
  • Lateral (Axillary Border)
  • Medial (Vertebral Border)
  • Superior
    
    • Suprascapular Notch (transmits Suprascapular A. and N.)
    • Coracoid Process
• Angles
  
  • Superior
  • Inferior
  • Lateral
    
    • Scapular Head
      
      • Glenoid Cavity
      • Supraglenoid Tubercle (attachment point for the Long Head of the Biceps Brachii M.)
      • Infraglenoid Tubercle (attachment point for the Long Head of the Triceps Brachii M.)
    • Scapular Neck
• Posterior Surface
  
  • Scapular Spine
    
    • Acromion
    • Deltoid Tubercle (Attachment point for the Deltoid M.)
  • Greater Scapular Notch
  • Supraspinous Fossa (location of Supraspinatus M.)
  • Infraspinous Fossa (location of Infraspinatus M.)
• Costal (Anterior) Surface
  
  • Subscapular Fossa (location of Subscapularis M.)

Question 3

Identify on Humerus

• Proximal End
  
  • Humeral Head
  • Humeral Neck
    
    • Anatomical Neck (between Humeral Head and Humeral Tubercles)
    • Surgical Neck (between Proximal End of Humerus and Shaft)
  • Greater Humeral Tubercle (attachment point for the Supraspinatus, Infraspinatus and Teres Minor M.)
  • Lesser Humeral Tubercle (attachment point for the Subscapularis M.)
  • Intertubercular Groove (transmits the Long Head of the Biceps Brachii T., attachment points for Pectoralis Major, Teres Maor and Latissimus Dorsi M.)
• Body (shaft)
  
  • Deltoid Tuberosity (insertion point for the Deltoid M.)
  • Groove for Radial N. (transmits the Radial N. and Deep Brachial A.)
• Distal End
  
  • Medial Supracondylar Ridge
  • Lateral Supracondylar Ridge
  • Lateral Humeral Epicondyle (common origin for several Antebrachial Extensors)
  • Medial Humeral Epicondyle (common origin for several Antebrachial Flexors)
    
    • Groove for Ulnar N. (transmits the Ulnar N.)
  • Humeral Condyle
    
    • Articular Surfaces
      
      • Trochlea (articulates with the Trochlear Notch of the proximal Ulna)
      • Capitulum (articulates with concave Radial Head)
    • Anterior Depressions
      
      • Radial Fossa (accommodates the Radial Head when the Antebrachium is flexed)
      • Coronoid Fossa (accommodates the Coronoid Process of the ulna when the Antebrachium is flexed)
    • Posterior Depression
      
      • Olecranon Fossa (accommodates the Olecranon of the Ulna when the Antebrachium is extended)

Question 4

Identify on Ulna

• Proximal End (larger than distal end)
  
  • Olecranon (point of the Elbow)
  • Coronoid Process
    
    • Radial Notch (articulates with the Radial Head)
  • Trochlear Notch (formed by the Olecranon and Coronoid Processes, grips the Humeral Trochlea)
  • Ulnar Tuberosity (distal to Coronoid Process; Attachment point for the Brachialis M.)
• Body
• Ulnar Head (possesses articular surface for articular disc, does not reach the Carpals)
  
  • Ulnar Styloid Process

Question 5

Identify on Radius

• Radial Head
  
  • Fovea of Radial Head (articulates with Capitulum of the Humeral Condyle)
• Radial Neck (slight constriction distal to the Radial Head)
  
  • Radial Tuberosity (attachment point for the Biceps Brachii T.)
• Body
• Distal End (quadrangular in cross-section, articulates with the ulna and proximal row of carpals)
  
  • Styloid Process of Radius (distal most point of the Radius, lateral constraint to the Radiocarpal Joint)
  • Ulnar Notch (articulates with Ulnar Head)
  • Radial Articular Surface for Carpal Bones (articulates with the Lunate and Scaphoid bones)
  • Dorsal Tubercle (acts as a pulley for the Extensor Pollicis Longus M.)

Question 6

Identify Carpals (8)

• Proximal Row (from lateral to medial)
  
  • Scaphoid (articulates with the Radius proximally and Trapezium and Trapezoid bones distally, most commonly fractured Carpal B., largest bone in the proximal row, exists in the floor of the Anatomical Snuffbox)
    
    • Scaphoid Tubercle (ligamentous attachment point)
  • Lunate (articulates with the Radius proximally, Scaphoid and Triquetrum on either side and the Capitate and Hamate bones distally)
  • Triquetrum (articulates with the Articular Disc of the Radiocarpal Joint proximally, Lunate laterally, Pisiform anteriorly and the Hamate distally)
  • Pisiform (articulates with the Triquetrum anteriorly)
• Distal Row (from lateral to medial)
  
  • Trapezium (articulates with the Scaphoid proximally, Trapezoid medially and 1st and 2nd Metacarpal bones distally)
    
    • Tubercle of the Trapezium
  • Trapezoid (articulates with the Scaphoid Proximally, Trapezium and Capitate on either side and the 2nd Metacarpal bone distally)
  • Capitate (largest Carpal bone, articulates with the Scaphoid and Lunate proximally, Trapezoid and Hamate on either side and the 3rd and 4th Metacarpal bone distally)
  • Hamate (articulates with the Triquetrum proximally, Capitate laterally and the 4th and 5th Metacarpal bones distally)
    
    • Hamulus (Hook) of Hamate

Question 7

Identify Metacarpals and Phalanges

• Metacarpal B. (1-5; from lateral to medial)
  
  • Base (proximal)
    
    • 1st (articulates with the Trapezium)
    • 2nd (articulates with the Trapezium and Trapezoid bones)
    • 3rd (articulates with the Capitate)
      
      • Styloid Process (lateral side)
    • 4th (articulates with the Capitate and Hamate bones)
    • 5th (articulates with the Hamate bone)
  • Body
  • Head
• Proximal Phalanges (1-5; from lateral to medial)
  
  • Base (proximal)
  • Body
  • Head (distal)
• Middle/Intermediate Phalanges (1-4; starting with index (2nd) finger, absent in the Pollux)
  
  • Base (proximal)
  • Body
  • Head (distal)
• Distal Phalanges (1-5; from lateral to medial)
  
  • Base (proximal)
  • Body
  • Head (distal)

Question 8

Chondrology

Sternoclavicular Joint

Acromioclavicular Joint

Glenoid Labrum

Articular Disc of Distal Radioulnar Joint

Answer 8

SC Joint: Articular Disc (Fibrocartilaginous disc in joint space)

AC Joint: Articular Disc (Fibrocartilaginous disc in joint space)

Glenoid Labrum: Fibrocartilaginous ring surrrounding and deepening the Glenoid Cavity

Articular Disc of Distal Radioulnar Joint: Fibrocartilaginous disc extending between the medial edge of the Ulnar Notch of the Radius and the Styloid Process of the Ulna (Triangular L.)