Chapter 5: Skeletal SystemChapter 5: Skeletal SystemThe Appendicular SkeletonThe Appendicular Skeleton

ShoulderShoulderArmArmLegLeg

PelvisPelvis

Pectoral Girdle (shoulder)Pectoral Girdle (shoulder)

Clavicle:Clavicle: aka: collarbone aka: collarbone– Articulates with the sternum Articulates with the sternum

and the scapulaand the scapula– Helps make the shoulder joint Helps make the shoulder joint

and an attachment point for and an attachment point for ligamentsligaments

Pectoral Girdle (shoulder)Pectoral Girdle (shoulder)

ScapulaScapula: aka shoulder : aka shoulder bladeblade– Acromion: the end of the Acromion: the end of the

spine that forms the spine that forms the shoulder jointshoulder joint

– Glenoid Cavity: a “pocket” Glenoid Cavity: a “pocket” for the head of the humerusfor the head of the humerus

– The shape of the scapula The shape of the scapula allows for muscles to attachallows for muscles to attach

Arm BonesArm Bones

HumerusHumerus– HeadHead: articulates with : articulates with

the glenoid cavitythe glenoid cavity

– CapitulumCapitulum: rounded : rounded knob that articulates knob that articulates with the radiuswith the radius

– TrochleaTrochlea: articulates : articulates with the ulnawith the ulna

Ulna and RadiusUlna and Radius

UlnaUlna: medial side of the : medial side of the forearmforearm– Trochlear NotchTrochlear Notch: curved : curved

area that receives the area that receives the trochlea of the humerustrochlea of the humerus

RadiusRadius: lateral side of : lateral side of the forearmthe forearm– Head: articulates with the Head: articulates with the

capitulum of the humeruscapitulum of the humerus

The Wrist, Hand, FingersThe Wrist, Hand, Fingers

Bones in each hand:Bones in each hand:

Carpals: 8 bones Carpals: 8 bones

Metacarpals: 5 bonesMetacarpals: 5 bones

Phalanges: 14 Phalanges: 14

PelvisPelvisCoxal BonesCoxal Bones: The : The hipbones that are made of hipbones that are made of three fused bonesthree fused bones– Ilium: superior; Ilium: superior; – Ischium: inferior and posteriorIschium: inferior and posterior– Pubis: inferior and anteriorPubis: inferior and anterior

Acetabulum: that pocket Acetabulum: that pocket found where the bone fusefound where the bone fuse

Dude or Dudette?Dude or Dudette?

•Female inlet (superior opening) is larger and more circular•Female bones are lighter and more thin•Female Ilia flare more laterally•Female ischial spines are shorter; outlet (inferior opening) is larger•Female pubic arch is more round as the bones are at a great angle

Nice Legs!Nice Legs!

FemurFemur: longest, heaviest, : longest, heaviest, strongest bone in the bodystrongest bone in the body– Head:Head: articulates with the articulates with the

acetabulumacetabulum– Greater and lesser Greater and lesser

trochanters:trochanters: muscle muscle attachment pointsattachment points

– Medial and Lateral Medial and Lateral CondylesCondyles: articulate with : articulate with the tibiathe tibia

Tibia and FibulaTibia and Fibula

TibiaTibia: shin bone: shin bone– Bears the weight of the legBears the weight of the leg– Articulates with the femur,, Articulates with the femur,,

fibula, and tarsal bonesfibula, and tarsal bones

FibulaFibula: parallel and lateral : parallel and lateral to the tibiato the tibia

KneeKnee

PatellaPatella: kneecap: kneecap– Maintains positions of the Maintains positions of the

quadriceps tendon and quadriceps tendon and increase its leverage on increase its leverage on the tibia.the tibia.

– Allow the knee to lock for Allow the knee to lock for bipedal locomotion.bipedal locomotion.

FootFoot

TarsalsTarsals: ankle bones: ankle bones– 7 bones7 bones– TalusTalus: Articulates with the : Articulates with the

tibia and fibula; has no tibia and fibula; has no muscle attachmentsmuscle attachments

– CalcaneusCalcaneus: heel bone: heel bone

Metatarsals: 5 bonesMetatarsals: 5 bones

Phalanges: 14 per footPhalanges: 14 per foot