Osteoporosis and vertebral collapse following low-dose, low molecular weight heparin therapy in a young patient.

Osteoporosis is a well-recognized complication of long-term heparin (unfractionated) therapy. It has been suggested that the low molecular weight heparins (LMWH) have a lower potential to cause osteopenia than the unfractionated preparations. We report a case of a 29-year-old woman who developed osteoporosis and pathological fracture of lumbar vertebrae following treatment with low dose LMWH (dalteparin) for 3 months. The aim of this report is to alert clinicians to the potential risk of this complication with the prolonged use of LMWH preparations--an increasingly popular choice for long-term anticoagulation.