1. What is the etiology of Mandy’s premature osteoporosis, and how is her condition thought to contribute to a decrease in bone density?

Mandy is a 16-year-old competitive figure skater who practices several hours a day with her coach at the skating arena. Because of her extremely active lifestyle and restricted diet to maintain her athletic physique, she experiences ongoing amenorrhea. One day during practice, she landed a jump and fell to the ice in pain. Her left foot swelled up almost immediately, making it difficult for her coach to remove the skate. At the hospital, radiographs revealed a fracture of the fifth metatarsal bone and general radiolucency of all the bones in her foot. A follow-up DXA revealed a bone mass of 2.7 standard deviations below mean.

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1. What is the etiology of Mandy’s premature osteoporosis, and how is her condition thought to contribute to a decrease in bone density?

2. Knowing what you do about bone mineralization, why does a deficiency of estrogen in women lead to osteoporotic change?

3. Osteoporosis and osteomalacia both involve abnormal bone mineralization. What are the general macroscopic differences of these two conditions?

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Mandy Case Study

Mandy is possibly indicating signs and impacts of the female athletic triad. This is characterized by extreme exercises and a restricted diet, which in most cases, minimizes fat stores as well as fat-to-muscle ratio among athletes. As a result, a reduction in estrogen production is experienced mainly by the ovaries with amenorrhea. Reduced estrogen production and circulation combined with limited consumption of calcium and vitamin D leads to bone resorption and development of osteoporosis (Bello Segura & Subauste, 2019). Various factors trigger osteoporosis. Bone density not only reduces with age but also the drugs used in the treatment of cancer, asthma, Addison’s disorders, arthritis…

Bone mineralization is a condition where the organic bone matrix is more than calcium phosphate nanocrystals, particularly in highly organized processes. The state is triggered by osteoblasts and directed to the organic osteoid matrix generated by osteoblasts. Osteoid comprise of type I collagen fibrils that are organized to develop the micro-and-macrostructures of the bone. Bone mineralization can be located at different levels and are critical to differentiate in the process of determining the impact of remodeling (Lips, Goldsmith & de Jongh, 2017). For instance, at the tissue level, bone mineralization is typically identified in terms of heterogeneity and degree of mineralization, which are not dependent on the quantity of tissue available. Estrogen deficiency not only leads to high loss of bone density in postmenopausal women but also in men. The condition is attributed to excessive bone resorption and limited formation of bones. Osteocytes, osteoblasts, and osteoclasts all contain estrogen receptors. Moreover, local growth tenets and cytokines are indirectly influenced by estrogen deficiency in women (Bello Segura & Subauste, 2019). The estrogen-replete condition can lead to osteoclast apoptosis through the high production of changing growth. However, in the absence of estrogen, T cells tend to enhance osteoblast growth, differentiation, and long-term survival through interleukin-1, IL6, and tumor necrosis factor. For instance, in murine research, where mice ovaries were removed, IL6 and granulocyte-macrophage…

Osteoporosis is a bone illness characterized by reduced bone density mainly due to bodyweight loss, thus unable to make bones. This results in highly fragile bones and increased potential to fracture, particularly in the spine, hip, shoulder, and wrist. In contrast, osteomalacia is an illness characterized by the softening of bones, mainly due to impaired bone metabolism caused by the insufficient supply of phosphate, vitamin D, and calcium. Resorption of calcium may also lead to osteomalacia. Moreover, the lack of identified minerals may also lead to inadequate bone mineralization. To some extent, the two conditions may be confusing (Bello Segura & Subauste, 2019).  The healthy human bone comprises of metallic components such as organic minerals such as collagen (40%), calcium hydroxyapatite (60%). However…

References

Bello Segura, M., & Subauste, J. (2019). MON-502 It’s Not Always Osteoporosis: FGF-23 Induced Osteomalacia. Journal of the Endocrine Society, 3(Supplement_1), MON-502.

Lips, P., Goldsmith, D., & de Jongh, R. (2017). Vitamin D and osteoporosis in chronic kidney disease. Journal of nephrology, 30(5), 671-675.

Almeida, M., Laurent, M. R., Dubois, V., Claessens, F., O’Brien, C. A., Bouillon, R., … & Manolagas, S. C. (2016). Estrogens and androgens in skeletal physiology and pathophysiology. Physiological reviews, 97(1), 135-187.