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Osteoporosis, the Elderly and Fractures

 Osteoporosis

 

Kyphosis

 

Fracture

I'll not bother you with a mega boring account of bone fracture repair, so here's a quick reminder of the steps instead:

  1. Haematoma formation
  2. Organisation of haematoma: cells involved are neutrophils, macrophages and fibroblasts. They're helped by platelet derived growth factor (PDGF), transforming growth factor ß (TGF-ß) and fibroblast growth factor (FGF).
  3. Osteoblast production and migration: the cortex lays down woven bone and the external callus produces cartilage.
  4. Bony union by woven bone: by this time - after 3rd week - the callus is well established (cartilage is replaced by woven bone) and remodelling by osteoclasts takes place to remove excess callus.
  5. Woven bone remodelled: the woven bone is replaced by lamellar trabecular bone (the trabeculae orientate to lines of stress).

 Factors that can delay healing

w poor blood supply

w poor general nutritional status

w poor apposition of fractured bone ends

w presence of foreign bodies

w presence of infection

w corticosteroid therapy

When the elderly fracture their bones, the things heal more slowly than in younger folk. (When I say the 'things', I meant the bones - though the elderly do heal more slowly too...) The factors featuring most prominently in this case are:

 

Disodium Etidronate (p 606 Katzung)

 

Oestrogen

Bendrofluazide is a thiazide diuretic. It has a beneficial effect on bone in that it reduces renal calcium excretion by increasing calcium reabsorption in the kidney. More calcium means less bone breakdown and Katzung says that this is how thiazides increase the effectiveness of parathyroid hormone (PTH).

 

"Don't confuse intelligence and wisdom. Intelligence tells you
it's raining, but it's wisdom that tells you to get out of it!"

-

Explains why even the most seemingly intelligent of us can make the most fantastic cock-ups. (The important thing though, is to learn from them!)

 

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