Diabetes and bone. 
Traditionally, patients with type 1 diabetes were regarded to be at an increased risk of fractures whereas type 2 diabetics were assumed to be protected from fractures since many of them have high bone mineral density.  Nevertheless, several clinical studies consistently demonstrated that type 2 diabetes is a paradigm of a disease with an increased risk of fractures in the presence of high bone mass.  The pathophysiology of decreased bone strength in diabetes mellitus is multifactorial: insulin deficiency, insulin resistance, osteoblast insufficiency, vitamin D deficiency, formation of advanced glycation end-products in bone, and microvascular complications appear to contribute.  Drugs used for the treatment of type 2 diabetes also may influence bone fragility: thiazolidinedione use has been associated with an increased risk of fractures.