Chapter 5: Skeletal System The Appendicular Skeleton Shoulder Arm Leg Pelvis Pectoral Girdle (shoulder) Clavicle: – Articulates with the sternum and the scapula – Helps make the shoulder joint and an attachment point for ligaments Pectoral Girdle (shoulder) Scapula: aka shoulder blade – Acromion: the end of the spine that forms the shoulder joint – Glenoid Cavity: a “pocket” for the head of the humerus – The shape of the scapula allows for muscles to attach Arm Bones Humerus – Head: articulates with the glenoid cavity – Capitulum: rounded knob that articulates with the radius – Trochlea: articulates with the ulna Ulna and Radius Ulna: medial side of the forearm – Trochlear Notch: curved area that receives the trochlea of the humerus Radius: lateral side of the forearm – Head: articulates with the capitulum of the humerus The Wrist, Hand, Fingers Bones in each hand: Carpals: 8 bones Metacarpals: 5 bones Phalanges: 14 Pelvis Coxal Bones: The hipbones that are made of three fused bones – Ilium: superior; – Ischium: inferior and posterior – Pubis: inferior and anterior Acetabulum: that pocket found where the bone fuse 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! Femur: longest, heaviest, strongest bone in the body – Head: articulates with the acetabulum – Greater and lesser trochanters: muscle attachment points – Medial and Lateral Condyles: articulate with the tibia Tibia and Fibula Tibia: shin bone – Bears the weight of the leg – Articulates with the femur,, fibula, and tarsal bones – Has the medial malleolus Fibula: parallel and lateral to the tibia -Has the lateral malleolus Knee Patella: kneecap – Maintains positions of the quadriceps tendon and increase its leverage on the tibia. – Allow the knee to lock for bipedal locomotion. Foot Tarsals: ankle bones – 7 bones – Talus: Articulates with the tibia and fibula; has no muscle attachments – Calcaneus: heel bone Metatarsals: 5 bones Phalanges: 14 per foot