C h a p t e r 8 The Appendicular Skeleton PowerPoint® Lecture Slides prepared by Jason LaPres Lone Star College - North Harris Copyright © 2009 Pearson Education, Inc., Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings publishing as Pearson Benjamin Cummings An Introduction to the Appendicular Skeleton . The Appendicular Skeleton . 126 bones . Allows us to move and manipulate objects . Includes all bones besides axial skeleton . The limbs . The supportive girdles Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings An Introduction to the Appendicular Skeleton Figure 8–1 The Appendicular Skeleton. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings An Introduction to the Appendicular Skeleton Figure 8–1 The Appendicular Skeleton. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . Also called the shoulder girdle . Connects the arms to the body . Positions the shoulders . Provides a base for arm movement . Consists of . Two clavicles . Two scapulae . Connects with the axial skeleton only at the manubrium Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . The Clavicles . Also called collarbones . Long, S-shaped bones . Originate at the manubrium (sternal end) . Articulate with the scapulae (acromial end) Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle Figure 8–2 The Clavicle. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . The Scapulae . Also called shoulder blades . Broad, flat triangles . Articulate with arm and collarbone . Anterior surface: the subscapular fossa Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . The Scapulae . Structures of the scapula . Body has three sides: – superior border – medial border (vertebral border) – lateral border (axillary border) . Body has three corners: – superior angle – inferior angle – lateral angle Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . The Scapulae . The scapular head . Holds glenoid cavity . Which articulates with humerus . To form shoulder joint . Processes of the glenoid cavity . Coracoid process: – anterior, smaller . Acromion: – posterior, larger – articulates with clavicle – at the acromioclavicular joint Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle Figure 8–3 The Scapula. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pectoral Girdle . The Scapulae . Posterior features of the scapula . Scapular spine: – ridge across posterior surface of body . Separates two regions: – supraspinous fossa – infraspinous fossa 3D Rotation of Scapula, Clavicle, and Humerus Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The upper limbs consist of the arms, forearms, wrists, and hands Note: arm (brachium) = 1 bone, the humerus Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Humerus . Also called the arm . The long, upper arm bone . Articulates with the pelvic girdle Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Humerus . Tubercles of the proximal epiphysis . Separated by the intertubercular groove: – greater tubercle: » lateral » forms tip of shoulder – lesser tubercle: » anterior, medial Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Humerus . Head: . Rounded, articulating surface . Contained within joint capsule . Anatomical neck: . Margin of joint capsule . Surgical neck: . The narrow metaphysis Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Humerus . The Shaft . Deltoid tuberosity: – a bulge in the shaft – attaches deltoid muscle . Radial groove: – for radial nerve – posterior to deltoid tuberosity Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Humerus . The distal epiphysis . Medial and lateral epicondyles: – for muscle attachment . Condyle of the humerus: – articulates with ulna and radius . Articular regions of the condyle . Trochlea: – coronoid fossa and olecranon fossa – articulates with ulna . Capitulum: – radial fossa – articulates with radius Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–4a The Humerus. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–4b The Humerus. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Forearm (also called the antebrachium) . Consists of two long bones . Ulna (medial) . Radius (lateral) Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Ulna . The olecranon . Superior end of ulna . Point of elbow . Superior lip of trochlear notch . Articulates with trochlea of humerus . The coronoid process . Inferior lip of trochlear notch Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Ulna . Articulations with the humerus . Forearm extended: – olecranon enters olecranon fossa . Forearm flexed: – coronoid process enters coronoid fossa . Other articulations . Radial notch: – articulates with head of radius – forms proximal radio-ulnar joint . Ulnar head: – prominent styloid process – attaches to articular disc between forearm and wrist Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–5a The Radius and Ulna. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Ulna . Interosseous membrane . A fibrous sheet . Connects lateral margin of ulnar shaft to radius Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Radius . Lateral bone of forearm . Disk-shaped radial head above the neck . Radial tuberosity below the neck, attaches biceps . Articulations of the radius . Ulnar notch: – distal end – articulates with wrist and radius . Styloid process: – stabilizes wrist joint Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–5b The Radius and Ulna. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . Eight carpal bones . Four proximal carpal bones . Four distal carpal bones . Allow wrist to bend and twist Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Four Proximal Carpal Bones . Scaphoid . Near styloid process . Lunate . Medial to scaphoid . Triquetrum . Medial to lunate bone . Pisiform . Anterior to triquetrum Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . The Four Distal Carpal Bones . Trapezium . Lateral . Trapezoid . Medial to trapezium . Capitate . Largest . Hamate . Medial, distal Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–6 Bones of the Wrist and Hand. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs . Metacarpal Bones . The five long bones of the hand . Numbered I–V from lateral (thumb) to medial . Articulate with proximal phalanges . Phalanges of the Hands (14 total finger bones) . Pollex (thumb) . Two phalanges (proximal, distal) . Fingers . Three phalanges (proximal, middle, distal) Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–6a Bones of the Wrist and Hand. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Upper Limbs Figure 8–6b Bones of the Wrist and Hand. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle . Made up of two hip bones (coxal bones) . Strong to bear body weight, stress of movement . Part of the pelvis . Coxal bones . Made up of three fused bones . Ilium (articulates with sacrum) . Ischium . Pubis Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle . Coxal Bones . The acetabulum . Also called the hip socket . Is the meeting point of the ilium, ischium, and pubis . Is on the lateral surface of the hip bone (coxal bone) . Articulates with head of the femur (lunate surface) . Acetabular notch . A gap in the ridge of the margins of the acetabulum Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle Figure 8–7a The Right Coxal Bone. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle Figure 8–7b The Right Coxal Bone. Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle . Marks of the Ilium . Greater sciatic notch . For sciatic nerve . Iliac crest . Upper brim . Iliac fossa . Depression between iliac crest and arcuate line Copyright © 2009 Pearson Education, Inc., publishing as Pearson Benjamin Cummings The Pelvic Girdle . Marks of the Ischium . Ischial spine . Above lesser sciatic notch . Ischial tuberosity . Posterior projection