* Angela M. Cheung, University Health Network-University of Toronto, CANADA, LIANNE TILE, University of Toronto, CANADA, R Bleakney, Mount Sinai Hospital, CAN, Aliya Khan, McMaster University, CANADA, Savannah Cardew, University of Toronto, CANADA, Rowena Ridout, Toronto Western Hospital, CANADA, Heather McDonald-Blumer, University of Toronto, CAN, Khalid Syed, University Health Network, Canada, Jessica Chang, University Health Network, Canada, Hanxian Hu, University Health Network, Canada, Suzanne Morin, McGill University, CANADA, Alexandra Papaioannou, Hamilton Health Sciences, CANADA, Robert Josse, St. Michael's Hospital, University of Toronto, CANADA, Earl Bogoch, St. Michael's Hospital, CANADA, Jonathan Adachi, St. Joseph's Hospital, Canada

Purpose: With the increased awareness of atypical femur fractures (AFFs), incomplete non-displaced fractures associated with bisphosphonate therapy are diagnosed more frequently, but optimal therapy for these fractures is unclear. We describe a case series of 13 patients with incomplete AFFs who have been treated with teriparatide therapy.

Methods: Thirteen patients who sustained an incomplete non-displaced AFF according to the criteria set forth by ASBMR were included. We assessed radiographic fracture healing using CT scans and plain radiographs, measuring the depth of the lucency line through the cortex and the degree that it extends around the circumference every 6 months. We also measured areal BMD at the total hip, femoral neck, lumbar spine and forearm by DXA (Hologic Discovery A, Hologic Inc.) every 6 months. Outcomes, such as pain, mobility, and progression or regression of incomplete fracture as well as need for surgical intervention, were also noted.

Results: All 13 patients were postmenopausal women (69.2% Caucasians, 15.4% Southeast Asians, 15.4% South Asians) with mean age of 68.6 (range 57.5- 81.0) years, mean BMI of 27.5kg/cm2 and mean serum 25-hydroxyvitamin D of 116.9 nmol/L at the time of diagnosis of incomplete AFF. All had normal ionized calcium and intact PTH. Eight out of thirteen had a previous complete AFF. Average duration of bisphosphonate use was 12.6 years (range 3.0-28.0 years). Mean BMD T-scores at the lumbar spine, total hip and femoral neck at the time of diagnosis of incomplete AFF were -1.87, -1.14 and -1.85, respectively. As of March 5, 2012, average duration of teriparatide therapy was 13.4 months (range: 1.4 to 20.2 months). Out of the 13 patients, 3 had to have prophylactic surgical repair for their incomplete AFFs (2 for debilitating pain and progression of incomplete fracture and 1 because of patient / physician preference). For the other 10 patients, 5 had radiographic improvement, 4 had no change and 1 progressed despite teriparatide. Improvement in pain corresponded to radiographic healing, but often preceded it. Of the 13 patients at last follow-up, only 2 did not require the use of an assistive device for mobility.

Conclusions: Based on limited observational data without a control group for comparison, it is unclear whether teriparatide improves fracture healing in patients with incomplete non-displaced AFFs. A randomized controlled trial examining the use of teriparatide in this population is urgently needed.

Disclosures: J. Adachi, Eli Lilly: Consulting fees or other remuneration (payment). J. Adachi, Eli Lilly: Speaker's Bureau. H. McDonald-Blumer, Eli Lilly: Speaker's Bureau. R. Josse, Eli Lilly: Speaker's Bureau. A. Khan, Eli Lilly: Speaker's Bureau. S. Morin, Eli Lilly: Speaker's Bureau. R. Ridout, Eli Lilly: Consulting fees or other remuneration (payment). E. Bogoch, Eli Lilly: Speaker's Bureau. S. Morin, Eli Lilly: Consulting fees or other remuneration (payment). A. Cheung, Eli Lilly: Consulting fees or other remuneration (payment). A. Papaioannou, Eli Lilly: Other. L. TILE, Eli Lilly: Consulting fees or other remuneration (payment). J. Adachi, Eli Lilly: Research Grants.

* Presenting Authors(s): Angela M. Cheung, University Health Network-University of Toronto, CANADA