Chapter 7: Appendicular Skeleton Flashcards
How many bones are in the appendicular skeleton?
126
Pectoral girdle
- Consists of clavicle and scapula
- Articulates the upper limbs with the trunk
Clavicle and scapula
- Position the shoulder joint
- Help move the upper limb
- Provide a base for muscle attachment
Where does the humerus articulate with the scapula?
Glenohumeral joint
Muscle attachment sites of the humerus
Greater and lesser tubercles
How many carpal bones are there?
8
How many metacarpal bones are there?
5
Characteristics of the wrist joint
- Carpus forms wrist
- 2 rows of short bones
- Distal row articulates with metacarpals
- Four fingers have 3 phalanges
- Pollex (thumb) has 2
- As a unit are convex posteriorly and concave anteriorly
Carpal tunnel
- On anterior surface
- Ligament from tubercle of trazpezium to hook of hamate
Pelvic girdle
- More massive than the pectoral girdle
- Consists of 2 os coxae
- Fusion of ilium, ischium, and pubis
Ilium
- Largest hip bone
- Within acetabulum, fused to the ischium posteriorly and the pubis anteriorly
- Pubic symphysis limits left to right
Ischium
The “sit down” bone which fuses with the ilium
Ischial tuberosity
- The most outstanding marking on the ischium
- Receives all the body’s weight when seated
Pubis
The most anterior portion of the coxal bone
Pelvis
- Composed of the hipbones, sacrum, and coccyx
Divisions of the pelvis
- False pelvis (greater)
- True pelvis (lesser)
False pelvis
The portion superior to the arcuate line
True pelvis
- In a line that extends along the ilialpectineal line (arcuate line and pectineal line) to the pubic symphysis
Sex differences between male and female pelvis
- Male angle of the ischium: 90 degrees or less
- Female angle of the ischium: 100 degrees or more
Femur
- Longest bone in the body
- Articulates with the tibia at the knee
Patella
Large sesamoid bone
Fibula
Parallels tibia laterally
How many tarsal bones are there?
7
Function of the arch of the foot
- Distribute the weight of the body between the heel and ball of foot
- Weight is distributed first to the calcaneus then to the lateral side of the foot to the ball of the feet
Major arches of the foot
- Transverse arch
- Medial longitudinal arch
- Lateral longitudinal arch
Factors that cause variation in the skeletal system
- Medical history
- Weight
- Gender
- Body size
- Muscle mass
- Age
When do age related changes occur in the skeletal system?
- About age 1
- Continue throughout life
