The Appendicular Skeleton

1. Composed of 126 bones • Appendages (limbs- arms and legs) • Pectoral girdle (holds your arms to the body) • Pelvic girdle (holds your legs to the body) The Appendicular Skeleton

2. The Appendicular Skeleton Figure 5.6b

3. Composed of two bones • Clavicle—collarbone • Scapula—shoulder blade • These bones allow the upper limb to have exceptionally free movement The Pectoral (Shoulder) Girdle

4. Bones of the Shoulder GirdleClavicle Figure 5.21b

5. Sternal end – articulates with the manubrium of the sternum; has a broad, flat surface. • Acromial end – articulates with the arcomion process of the scapula; has a thin, curved surface. Clavicle

6. Bones of the Shoulder GirdleScapula Figure 5.21c–d

8. Acromion process – enlarged end of the spine; articulates with clavicle. • Coracoid process – other beak like projection that points over the top of the shoulder and anchors muscles of the arm. • Glenoid Cavity – shallow socket that receives the head of the arm bone (humerus). • Spine – Ridged projection on posterior surface. • Supraspinous fossa – depressed area above spine. • Infraspinous fossa – depressed area below spine. Scapula

9. Medial border, Lateral border, superior border self- explanatory • Inferior angle – most inferior “point” • Superior angle – most superior “point” that is not the acromion or coracoid Scapula

10. Humerus • Forms the arm • Single bone Bones of the Upper Limbs

11. Humerus • Head – rounded end; fits in glenoid cavity of scapula. • Anatomical Neck – inferior to head; slight constriction. • Greater & lesser tubercles – muscle attachments • Intertubercle Groove – anterolateral to head; separates greater and lesser tubercles. • Deltoid tuberosity – midpoint of shaft; roughened area that is site of attachment for deltoid muscle

12. Medial and Lateral Epicondyles – flank depressions at distal end of humerus; allow ulna to move freely when elbow is bent and extended. Coronoid fossa – anterior depression for coronoid process of ulna Radial fossa – lateral to coronoid fossa; articulates with radial head. Olecranon fossa – posterior depression for olecranon process of ulna Humerus

13. Capitulum – rounded knob lateral to trochlea, articulates with head of radius Trochlea – rounded spool-shaped medial distal end, articulates with ulna Humerus

14. The forearm has two bones • Ulna • Medial bone in anatomical position • Radius • Lateral bone in anatomical position Bones of the Upper LimbsUlna and Radius

16. Head – disc-shaped; forms joint with capitulum of humerus Radial tuberosity – bump, below head of radius, attachment point for tendons of bicep muscle Ulnar Notch – articular surface at distal end; narrow, concave, smooth, and articulates with the distal end of the ulna forming the distal radioulnar joint Styloid process – palpable projection on distal end Radius (thumb/lateral side)

17. Olecranon process - proximal end, posterior projection that makes up elbow. Coronoid process – proximal end, anterior projection that makes up the elbow. Trochlear notch - separate coronoid and olecranon processes; toward medial side Radial notch - narrow, oblong, articular depression on the lateral side of the coronoid process; it receives the head of the radius. Ulna (medial/pinky side)

18. Head - adjacent to styloid process at distal end; forms distal radioulnar joint. Styloid process - distal end, projects from the medial and back part of the bone; it descends a little lower than the head, and its rounded end affords attachment to a ligament of the wrist. Ulna (medial/pinky side)

19. The hand • Carpals—wrist • Metacarpals—palm • Phalanges—fingers Bones of the Upper LimbsCarpals, Metacarpals,Phalanges