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Bone disease

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Rickets (osteomalacia in adults)

Rickets is a bone softness conditions affecting children, often following from malnutrition, and causing bone fractures and other symptoms. It is one of the most prevalent childhood diseases in developed areas. The cause is insufficient calcium, vitamin D or phosphorus, sometimes passed on during pregnancy as the foetus develops.

Symptoms are bone fragility and deformities such as bowed legs in toddlers and windswept knees in children, as well as dental, pelvic and spinal deformities and problems.

Osteomalacia is an equivalent condition that occurs in adults, mainly due to vitamin D deficiency. It can also develop due to a lack of sufficient calcium or phosphate, or due to calcium resorption. Symptoms are diffuse pain throughout the body, muscle weakness and bone fragility.

Treatment for rickets and osteomalacia involves supplementation of vitamin D alongside calcium to redress mineral homeostasis. This also acts as a preventative measure against these diseases. Sunlight exposure also contributes to the prevention or treatment of rickets and osteomalacia.


Osteoporosis

Osteoporosis is an aging-related condition where decreasing bone density puts patients at higher risk of fractures. Causes include increased bone resorption compared to bone formation, which overall reduces the bone density. This bone remodelling process is constant, and is susceptible to various factors including exercise and hormones.

Symptoms are not obvious, and the condition is discovered upon bone fracture, often in the back, hip or forearm. Treatment includes weight-bearing workouts, hormones if necessary, and drugs where a fracture has already occurred.



Bone density increases into early adulthood and starts decreasing into middle age with no interventions. Vitamin D and calcium supplementation may or may not have an effect on developing osteoporosis. Wight training does stimulate bone density increase, so can redress osteoporosis, while taking hormones e.g. following removal of ovaries or testes, or if estrogen or testosterone are below optimal level for bone density maintenance for any other reason, can prevent osteoporosis development.

Drugs such as bisphosphonates have been shown to improve outcomes in patients who have already suffered a fracture due to osteoporosis.


Brittle bone disease (osteogenesis imperfecta)

OI is a genetic condition of many different types, ranging from mild to severe, that involves collagen formation. The lack of type I collagen, or its insufficient production, leads to blue eye sclerae, short stature, tooth problems, loose joints, poor muscle tone, breathing problems and hearing loss.

Some types are caused by spontaneous mutations in the patient, causing the condition; while others are caused by inherited mutations of the autosomal kind. The mutation is in the collagen-producing gene, affecting connecting tissue.




Treatment involves physiotherapy and exercise, assistive items such as braces and wheelchairs, or surgery to insert metal rods through the long bones to improve strength and prevent fractures.

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