The Appendicular Skeleton Includes Limbs appendages Pectoral girdle

The Appendicular Skeleton • Includes: – Limbs (appendages) – Pectoral girdle (Shoulder joint) – Pelvic girdle (hip joint) © 2015 Pearson Education, Inc.

The Pectoral (Shoulder) Girdle • Composed of two bones that attach the upper limbs to the axial skeleton 1. Scapula 2. Clavicle • Allows the upper limb a great deal of freedom © 2015 Pearson Education, Inc.

Figure 5. 23 a Bones of the shoulder girdle. Acromioclavicular joint Clavicle Scapula (a) Articulated right shoulder (pectoral) girdle showing the relationship to bones of the thorax and sternum

Figure 5. 23 b Bones of the shoulder girdle. Sternal (medial) end Posterior Acromial (lateral) end Superior view Acromial end Anterior Sternal end Posterior Inferior view (b) Right clavicle, superior and inferior views

Figure 5. 23 c Bones of the shoulder girdle. Suprascapular notch Coracoid process Superior angle Spine Acromion Glenoid cavity at lateral angle Medial border Lateral border (c) Right scapula, posterior aspect

Figure 5. 23 d Bones of the shoulder girdle. Acromion Suprascapular notch Superior border Superior angle Coracoid process Glenoid cavity Lateral (axillary) border Medial (vertebral) border Inferior angle (d) Right scapula, anterior aspect

The Arm • One bone: The Humerus – At the proximal end, the head articulates with the glenoid cavity of the scapula • This is a ball and socket joint – At the distal end, the trochlea and capitulum articulate with the bones of the forearm © 2015 Pearson Education, Inc.

Figure 5. 24 a Bones of the right arm and forearm. Greater tubercle Lesser tubercle Head of humerus Anatomical neck Intertubercular sulcus Deltoid tuberosity (a) Radial fossa Coronoid fossa Medial epicondyle Capitulum Trochlea

Figure 5. 24 b Bones of the right arm and forearm. Head of humerus Anatomical neck Surgical neck Radial groove Deltoid tuberosity Medial epicondyle (b) Trochlea Olecranon fossa Lateral epicondyle

The Forearm • Two bones 1. Ulna—medial bone in anatomical position • Proximal end articulation – Coronoid process and olecranon articulate with the humerus 2. Radius—lateral bone in anatomical position • Olecranon gives us the distinct elbow © 2015 Pearson Education, Inc.

Figure 5. 24 c Bones of the right arm and forearm. Trochlear notch Olecranon Head Neck Radial tuberosity Coronoid process Proximal radioulnar joint Radius Ulna Interosseous membrane (c) Radial styloid process Ulnar styloid process Distal radioulnar joint

Hands • Carpals—wrist – arranged in two rows of 4 bones in each hand – Scaphoid, lunate, triquetrum, pisiform (Row 1) – trapezium, trapezoid, capitate, hamate (Row 2) • “some lovers try positions that they can’t handle” • Metacarpals—palm (5 per hand) • Phalanges—fingers and thumb – In each finger, there are 3 bones – In the thumb, there are only 2 bones • Thumb is called the pollex © 2015 Pearson Education, Inc.

Figure 5. 25 Bones of the right hand, anterior view. Distal Phalanges (fingers) Middle Proximal Metacarpals (palm) Carpals (wrist) 5 4 3 2 1 Hamate Trapezium Pisiform Trapezoid Triquetrum Scaphoid Capitate Lunate Ulna Radius