ORIGINAL ARTICLE The use of intravenous bisphosphonate therapy to treat vertebral fractures due to osteoporosis among boys with Duchenne muscular dystrophy A. M. Sbrocchi & F. Rauch & P. Jacob & A. McCormick & H. J. McMillan & M. A. Matzinger & L. M. Ward Received: 2 June 2011 /Accepted: 21 December 2011 # International Osteoporosis Foundation and National Osteoporosis Foundation 2012 Abstract Summary The impact of intravenous bisphosphonate treatment to treat painful vertebral fractures in boys with DMD has not been documented. In this retrospective observational study of seven boys, 2 years of intravenous bisphosphonate therapy was associated with back pain improvement and stabilization or increases in the height ratios of fractured vertebrae. Introduction Boys with Duchenne muscular dystrophy (DMD) are at risk for vertebral fractures. We studied the impact of intravenous bisphosphonate therapy for the treatment of painful vertebral fractures in DMD. Methods This was a retrospective observational study in sev- en boys with DMD (median 11.6 years, range 8.5 to 14.3) treated with intravenous pamidronate (9 mg/kg/year) or zole- dronic acid (0.1 mg/kg/year) for painful vertebral fractures. Results At baseline, 27 vertebral fractures were evident in the seven boys. After 2 years of bisphosphonate therapy, 17 of the fractures had an increase in the most severely affected vertebral height ratio, 10 vertebrae stabilized, and none showed a decrease in height ratio. Back pain resolved com- pletely (N 0 3) or improved (N 0 4). The median change in lumbar spine volumetric bone mineral density Z-score was 0.5 standard deviations (interquartile range, -0.3 to 1.7). Two boys had three incident vertebral fractures in previous- ly normal vertebral bodies that developed over the observa- tion period. There was a decline in the trabecular bone formation rate on trans-iliac bone biopsy but no evidence of osteomalacia. First-dose side effects included fever and malaise (N 0 4), hypocalcemia (N 0 2), and vomiting (N 0 1); there were no side effects with subsequent infusions. Conclusions Intravenous bisphosphonate therapy was asso- ciated with improvements in back pain and stabilization to improvement in vertebral height ratios of previously frac- tured vertebral bodies. At the same time, such therapy does not appear to completely prevent the development of new vertebral fractures in this context. Keywords Bisphosphonates . Bone histomorphometry . Bone mineral density . Clinical/pediatrics . Corticosteroid osteoporosis . Vertebral fractures Abbreviations BMD Bone mineral density CTx C-telopeptides of type I collagen DMD Duchenne muscular dystrophy GC Glucocorticoid IQR Interquartile range Introduction Duchenne muscular dystrophy (DMD) is characterized by progressive muscle weakness and loss of ambulation A. M. Sbrocchi : L. M. Ward (*) Division of Endocrinology, Children’ s Hospital of Eastern Ontario, 401 Smyth Rd., Ottawa, ON, Canada K1H 8L1 e-mail: lward@cheo.on.ca F. Rauch Genetics Unit, Shriners Hospital for Children, Montreal, QC, Canada P. Jacob : A. McCormick : H. J. McMillan Division of Neurology, Children’ s Hospital of Eastern Ontario, Ottawa, ON, Canada M. A. Matzinger Department of Diagnostic Imaging, Children’ s Hospital of Eastern Ontario, Ottawa, ON, Canada Osteoporos Int DOI 10.1007/s00198-012-1911-3 Author's personal copy