1. APPENDICULAR SKELETON ENDOSKELETON OF VERTEBRATES

2. The Appendicular Skeleton

Theappendicular skeletonincludes:

• Pectoral girdle

• Pelvic girdle

• Upper extremities

• Lower extremities

Theappendicular skeletonfunctions primarily to facilitate movement

3. Fig. 9.4 4. Tetrapod Limb

Typical 4 limbs

Primarily a modification of the Rhipidistian fin

wings paddles Lost 2 Lost 4 Modified elements 5.

Recall:V p= V g+ V e+ V gxe

V = variation

p = phenotypic

g = genotypic

e = environmental

Morphology (anatomy) Behavior & Performance Resource use (ecology) Fitness 6. Three main components

With respect to the pectoral and pelvic girdles:

• Serially homologous

• Propodium (= stylopodium) upper arm, upper leg

• Epipodium (= zeugopodium) forearm, shin

• Autopodium manus or pes (digits, and wrist and palm, or ankle and sole

7.

Mesopodium

Metapodium

Phalanges

8. 9. Fig. 9.12 10. 11. 12. Focus 9.2 13. Pectoral (Shoulder) Girdle

Thepectoral orshoulder girdleattaches the bones of the upper limbs to the axial skeleton

Consists ofscapula&clavicle

Claviclearticulates withsternum( sternoclavicular joint )

Claviclearticulates withscapula( acromioclavicular joint )

Scapulaheld in place by muscle only

Upper limb attached topectoral girdleat shoulder ( glenohumeral joint )

14. Clavicle (Collarbone)

S-shaped bone with two curves

Extends fromsternumtoscapulaabove 1st rib

Sternal & acromial extremities

One of the most commonly fractured bones in the human body

Fracture site is junction of curves

Ligaments attached toclaviclestabilize its position.

Shoulder separationis sprain of theacromioclavicular ligament

15. Anterior Surface of Scapula

Articulates with theclavicleand thehumerus

Subscapular fossafilled with muscle

Coracoid processfor muscle attachment

16. Posterior Surface of Scapula

Triangular flat bone found in upper back region

Scapular spineends asacromion process

Glenoid cavityforms shoulder joint with head ofhumerus

Supraspinous&infraspinous fossafor muscular attachments

17. Upper Extremity

Upper extremity consists of 30 bones

• Humeruswithin the arm

• Ulna&radiuswithin the forearm

• Carpalbones within the wrist

• Metacarpalbones within the palm

• Phalangesin the fingers

Joints

• Shoulder( glenohumeral ),elbow ,wrist ,metacarpophalangeal ,interphalangeal

• Shoulder dislocationis separation of thehumerusfrom theglenoid cavityof thescapula

18. Shoulder Dislocation

Head of humerus slips out of glenoid cavity

Closed reduction is term for slipping humerus back into place without surgery

Severe or frequent dislocations may require surgical ligament repair

19. Humerus: Proximal End

Largest and longest bone of upper extremity, part of shoulder joint, articulates withscapula

Head

Greater&lesser tubercles

for muscle attachments

Intertubercular

sulcusorbicipital

groove

Shaftorbody

20. Humerus: Distal End

Forms elbow joint withulnaandradius

Capitulum

• articulates with head ofradius

Trochlea

• articulation withulna

Olecranon fossa

• posterior depression forolecranon processofulna

Medial&lateral epicondyles

• attachment of forearm muscles

21. Ulna & Radius: Proximal End

Ulna(on little finger side)

• Trochlear notcharticulates with humerus&radial notchwithradius

• Olecranon processforms point of elbow

Radius(on thumb side)

• Head articulates withcapitulumofhumerus&radial notchofulna

• Tuberosityfor muscle attachment

22. Ulna & Radius: Proximal End

Radius(on thumb side)

• Headarticulates withcapitulumofhumerus&radial notchofulna

• Tuberosityfor muscle attachment

• Ulnar notcharticulates with ulna

23. Elbow Joint

Articulation ofhumeruswithulnaandradius

Ulnaarticulates withtrochleaofhumerus

Radiusarticulates withcapitulumofhumerus

Interosseousmembrane betweenulna&radiusprovides site for muscle attachment

24. Ulna and Radius: Distal End

Ulna

• Styloid processprovides attachment forulnar collateral ligament

• Head separated from wrist joint byfibrocartilage disc

Radius

• Forms wrist joint withscaphoid ,lunate&triquetrum

• Formsdistal radioulnar jointwith head ofulna

25. 8 Carpal Bones (Wrist)

Proximal row - lateral to medial

• Scaphoid : boat shaped

• Lunate : moon shaped

• Triquetrum : 3 corners

• Pisiform : pea shaped

Distal row - lateral to medial

• Trapezium : four sided

• Trapezoid : four sided

• Capitate : large head

• Hamate : hooked process

S caredL oversT ryP ositionsT hatT heyC antH andle 26. Metacarpals and Phalanges

Metacarpals

• 5 total: #1 proximal to thumb

• base ,shaft ,head

• knuckles ( metacarpophalangealjoints)

Phalanges (Digits)

• 14 total: each is calledphalanx

• proximal ,middle ,distalon each finger, except thumb

• base ,shaft ,head

27. Pelvic Girdle and Hip Bones

Pelvic girdle= two hip bones united atpubic symphysis

• articulate posteriorly withsacrumatsacroiliac joints

Each hip bone ( os coxa ) =ilium ,pubis , andischium

• fuse after birth atacetabulum

Bony pelvis = 2 hip bones,sacrumandcoccyx

28. Ilium

Iliac crestandiliac spinesfor muscle attachment

Iliac fossafor muscle attachment

Gluteal linesindicating muscle attachment

Sacroiliac jointatauricular surface&iliac tuberosity

Greatersciatic notchforsciatic nerve

29. Ischium and Pubis

Ischium

• Ischial spine&tuberosity

• Lesser sciatic notch

• Ramus

Pubis

• Body

• Superior&inferior ramus

• Pubic symphysisis pad offibrocartilagebetween 2pubic bones

30. Female PelvisMale Pelvis

Many differences between the two

In particular,pubic archin males is usually less than 90, whereas in females it is usually greater than 90

31. Lower Extremity

Each lower limb = 30 bones

• femurandpatellawithin the thigh

• tibia&fibulawithin the leg

• tarsalbones in the foot

• metatarsalswithin the forefoot

• phalangesin the toes

Joints

• hip, knee, ankle

• proximal&distal tibiofibular

• metatarsophalangeal

32. Femur

Thefemuror thighbone is the largest, heaviest, and strongest bone of the body

It articulates with thehip boneand thetibia

• Headarticulates