Bone Growth and Maintenance

Importance of Vitamins and Minerals

• Adequate vitamin and mineral intake necessary for bone growth and maintenance.
• Healthy diet is crucial.

Vitamin C

• Necessary for collagen synthesis.
• Deficiency leads to weakened bones, skin, ligaments (known as scurvy).
• Historical relevance: Often called pirates' disease due to deficiency on long sea voyages.

Vitamin B12

• Important for osteoblast activity.
• Deficiency can lead to inefficient bone metabolism and osteoporosis over time.

Vitamin D

• Active form: Calcitriol.
• Can be synthesized by the body with sunlight exposure.
• Increases calcium absorption in intestines, affects bone resorption, and increases osteoclast activity.

Human Growth Hormone (HGH)

• Anabolic hormone affecting bone growth.
• Targets release of insulin-like growth factors (IGFs).
• IGFs increase chondrocytes division and osteoblast activity.
• Excess HGH after growth plates close leads to acromegaly; deficiency can cause certain types of dwarfism.

Sex Hormones

• Estrogen and testosterone increase osteoblast activity and decrease osteoclast activity.
• Estrogen decline during menopause leads to decreased bone density.
• Testosterone deficiency can lead to low bone mass.

Bone Disorders

Osteomalacia and Rickets

• Softening of bones due to non-hardening.
• Caused by calcium or vitamin D deficiency, or sometimes genetic factors.

Osteogenesis Imperfecta

• Improper collagen formation leads to brittle bones.
• Results in frequent fractures and characteristic bluish tint to the sclera of eyes.

Myositis Ossificans

• Rare disorder where bone invades non-bone tissues, leading to muscle hardening.

Cranio Diaphyseal Dysplasia

• Calcium deposits on cranium narrow foramens, affecting nerves and vessels.
• Known as "lionitis," depicted in media.

Osteoporosis

• Weakening of already formed bone, prevalent in women over 50.
• Results from decreased estrogen reducing osteoblast activity.
• Affected by vitamin D intake, exercise, medications, and lifestyle choices (e.g., alcohol, smoking).
• Primarily affects bones with high spongy bone content.

Prevention and Management of Osteoporosis

• Focus on diet and exercise to enhance bone health.
• Recognize factors like hereditary, alcohol, and smoking impacting bone density.