SKELETAL SYSTEM

• Organs

– bones

– ligaments

– cartilages

– joints

• Skeletal System Functions

– Support & Protection

– Movement

– Mineral storage

– Blood cell production

– Leverage

• Classification of bones

– Long bones

– “Other Bones”

• Short

• Flat

• Irregular

• Sesamoid

• Wormian

• Structure of long bones

• Structure of “other bones”

• Bone Development and Growth

– Intramembranous ossification

§ Mesenchymal CT converted into bone

– Endochondral ossification

§ Cartilage converted into bone

– Increasing Length of Bone

§ Requires the epiphyseal plates

– Appositional growth (Increase in thickness)

§ requires the osteoblasts from the periosteum

· Bone Remodeling

– Requires osteoblasts and osteoclasts

· Factors Regulating Bone Growth

– Growth hormone

– Thyroid hormone

– Sex hormones`

– Vitamin A and C

– Vitamin D

Aging and the Skeletal System

• Osteoporosis: Non-modifiable risk factors:

– Being female

– Thin and/or small frame

– Advanced age

– A family history

– Early menopause

– Amenorrhea

– Caucasian or Asian descent

– Being post-menopausal

• Osteoporosis: Modifiable Risk Factors

– Smoking

– High protein diets

– Sedentary lifestyles

– Excessive exercise

– Some drugs (e.g. corticosteroids)

– Anorexia nervosa or bulimia nervosa

· Some Symptoms of 0steoporosis

– Verebral Fractures

– Kyphosis

• Prevention of Osteoporosis

– A calcium rich diet (dairy and/or non-dairy sources)

– Weight bearing exercises

– Avoidance of risk factors

· Intervertebral Disks

· Herniated Disks

· Curvatures of the Spinal Column

· Development of Spinal Curvatures

· Arches of the Foot

– Longitudinal

§ Medial and Lateral

– Transverse

Ø Arches maintained by ligaments