Appendicular Skeleton Lecture

Introduction

• Follow-up lesson from the axial skeleton
• Focus: Appendicular skeleton
• Features and functions of the appendicular skeleton
• Importance for tests/exams: Labeling bones and knowing their functions

Definition

• Appendicular Skeleton: Refers to the bones that are not in the central column of the body (arms, legs, pelvis)
• Axial Skeleton: Includes rib cage, sternum, vertebral column, and skull

Functions of Appendicular Skeleton

1. Attaches lower limbs to axial skeleton
2. Transmits weight from upper body to lower body
3. Supports and protects organs in the pelvic area (urinary, reproductive, digestive systems)
4. Provides attachment points for many muscles

Pectoral Girdle (Upper Limb Bones)

• Scapula: Shoulder blade
• Clavicle: Collar bone
• Humerus: Largest arm bone (upper arm)
• Radius: Bone in the forearm, in line with the thumb
• Ulna: Bone in the forearm, opposite the radius
• Carpals: Wrist bones (mnemonic: use hand to drive a car)
• Metacarpals: Bones of the palm
• Phalanges: Finger bones; both fingers and toes

Pelvic Girdle (Lower Limb Bones)

• Ilium: Large wing-like bones on either side
• Ischium: 'Bum bone,' bone you sit on
• Pubis: Bone that meets in the front, part of the pelvic bone
• Sacral Bone: Central bone, part of axial skeleton
• Acetabulum: Socket where femur joins the pelvic bone

Lower Limb and Feet Bones

• Femur: Upper leg bone, largest and densest bone, supports body weight
• Patella: Kneecap
• Tibia: Larger inner leg bone
• Fibula: Smaller outer leg bone (mnemonic: chicken drumstick analogy)
• Tarsals: Ankle bones
• Metatarsals: Arch of the foot bones
• Phalanges: Toe bones

Recap

• Pectoral Girdle: Scapula, clavicle, humerus, radius, ulna, carpals, metacarpals, phalanges
• Pelvic Girdle: Ilium, ischium, pubis
• Lower Limb: Femur, acetabulum, tibia, fibula, patella, tarsals, metatarsals, phalanges

Conclusion

• Important terminology for flashcards
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