Spontaneous fracture: multiple causes.

Spontaneous fractures occur in seemingly normal bone with no apparent blunt-force trauma. Spontaneous fracture occurs primarily in two distinct groups of patients: the very active young and the elderly. Researchers and clinicians have used several terms interchangeably for spontaneous fracture, including pathologic fracture, fragility fracture, compression fracture, or fatigue or insufficiency fracture. Among the most common causes of spontaneous fracture are osteoporosis (calcium deficiency and corticosteroid-induced), malignancy, overexposure to vitamin A, periprosthetic weakening, Brucellosis, cerebral palsy (especially in children), and osteodystrophy because of chronic renal failure. Preliminary research observations indicate that spontaneous fracture may be a rare adverse outcome associated with bisphosphonates.