Question

Mary-Lou’s family was happy with the management plan established by the doctor as Mary-Lou was progressing quite well. She was using notepads to jot down reminders, a pillbox to keep her medication organized and a calendar to record appointments. Her family members were helping her with routine tasks such as cooking and paying bills. She was feeling much happier and did not have to rely on alcohol to go to sleep. On one particular day she was feeling so good she decided to walk to her GP appointment alone. On her way there she stumbled over a branch and fell. She felt excruciating pain in her hip. A passer-by called an ambulance and she was taken to the emergency department at the Royal Melbourne hospital. An X-ray revealed that she had broken the neck of her femur and had to have surgery to repair it. Mary-Lou wondered whether this was linked to the crepitus she had been experiencing in her joints. Her joints did feel quite stiff and painful lately. The specialist explained to Mary-Lou that the crepitus was likely due to degeneration of her cartilage and said that the fracture might have been due to weakened bones. He told her he would like her to have a bone mineral density test to measure her bone density. The DEXA scan gave a T-score of -3.0. Mary-Lou is now given bisphosphonates and told to increase her daily intake of calcium

Q8 Considering Mary-Lou’s T-score, identify the condition she suffers from, briefly describe the pathogenesis of this disease, and explain why bisphosphonate administration is helpful in this condition.

Answer 1

Dexa scan of -2.5 or less than that is considered to due to osteoporosis. Lack of sufficient minerals especially Ca and Phosphates reduces bone density. Bone becomes brittle and weak. Such weak and brittle bones due to loss of bone matter is called osteoporosis.

It occurs very commonly in women after menopause. Reproductive hormones like oestrogen is important in pumping Ca in to bones. AFter menopause, lower levels of oestrogen will lead to decreased Ca levels in bones making the bones brittle. The disease is due to number of factors such as , lack of hormones, deficient dietary intake, deficiency in Vitamin D and life style. Hyper activity of parathyroid gland and increased production Parathormone (PTH) can lead to more bone resorption making less bone density. Oestrogen in woman is very important in keeping the bones strong. The oestrogen hormone not only helps in adding minerals to the bone to make it stronger, it also prevents bone resorption. Osteoblasts are bone cells which help in formation of bone and osteoclasts are the cells of bone which brings absorption of bone mass. Oestrogen prevents osteoclast activity. But if oestrogen is not there, osteoclast activity increases.

Bisphosphate prevents osteoclast activity of the bone and hence strengthens bone by increasing its mass. Because osteoclast based bone resorption is the main reason for osteoporosis.