This week the Donnelly Lab visited Prof. Donnelly’s K01 mentor Prof. Deepak Vashishth’s lab at RPI to learn biochemistry techniques for analysis of collagen in bone. Thanks to Dr. Gyna Sroga and Catalina Bravo for teaching us these assays, and to the Vashishth Lab for hosting us!
Prof. Donnelly, with co-chairs Dr. Dr. Joseph Lane and Dr. Adele Boskey, have invited basic scientists and clinicians with common interests in bone quality to convene for the 2013 AAOS/ORS Bone Quality and Fracture Prevention Research Symposium May 16-18 2013. Topics include contributions of microarchitecture and microstructure to bone quality, methods of assessment of bone quality, animal models of altered bone quality, human diseases that affect bone quality, effects of pharmacologic treatments on bone quality, and strategies for the management of patients with altered bone quality.
The American Society for Bone and Mineral Research has awarded Prof. Donnelly the Harold M. Frost Young Investigator Award. She will accept the award at the Sun Valley Workshop on Skeletal Biology in Sun Valley, ID August 4-7 2013. More information is available at the ASBMR award announcement.
As part of the celebrations for the 150th anniversary of the Hospital for Special Surgery, Prof. Donnelly presented a talk entitled, “Collagen as a Determinant of Bone Properties” at the Adele L. Boskey, Ph.D. Symposium on Mineralized Tissues. The symposium honored Dr. Boskey’s 40-year career devoted to investigation of the mechanism of biologic mineralization, as well as to mentoring young investigators.
Michelle Chin was awarded an Engineering Learning Initiatives Undergraduate Research Award for her proposal entitled, “Effect of bisphosphonates on bone tissue composition in postmenopausal women with fragility fractures.” The ELI grant will support her work in the lab this summer. Congratulations Michelle!
PhD student Ashley Lloyd was awarded a National Science Foundation Graduate Research Fellowship. NSF received over 13,000 applications for the 2013 competition and made 2,000 award offers. Congratulations Ashley!
Despite having higher than average bone density, patients with type 2 diabetes paradoxically have increased risk of fracture relative to individuals without diabetes. NIH/NIAMS has awarded Prof. Donnelly a career development grant to investigate the changes in collagen properties that occur in bone tissue with type 2 diabetes and their relationship to fracture risk. Key collaborators include Prof. Deepak Vashishth at Rensselaer Polytechnic Institute and Dr. Joseph Lane at the Hospital for Special Surgery.
Abstract
Purpose of review: To review the definition, epidemiology, and putative pathophysiology of atypical femoral fractures and propose strategies for the management of patients with atypical fractures as well as patients on long-term bisphosphonates without atypical fractures.
Recent findings: Recent epidemiologic evidence shows that the absolute incidence of atypical femoral fractures is small compared with the incidence of typical hip fractures. However, long-term bisphosphonate use may be an important risk factor for atypical fractures, and minimal additional antifracture benefit has been demonstrated for treatment durations longer than 5 years for patients with postmenopausal osteoporosis. This review gives advice to aid clinicians in the management of patients with incipient or complete atypical fractures.
Summary: Extremely limited evidence is available for how best to manage patients with atypical fractures. A comprehensive metabolic approach for the management of patients on long-term bisphosphonates will help to prevent oversuppression of bone remodeling that is implicated in the pathogenesis of these fractures.
The American Society for Bone and Mineral Research has awarded Prof. Donnelly the 2012 Junior Faculty Osteoporosis Research (JFOR) Award to support her proposal, “Spectroscopic and Biochemical Markers of Bone Quality in Patients with Atypical Femoral Fractures.” She will accept the award at the ASBMR annual meeting on 14 October 2012.
Reduction of bone turnover with bisphosphonate treatment alters bone mineral and matrix properties. Our objective was to investigate the effect of bisphosphonate treatment on bone tissue properties near fragility fracture sites in the proximal femur in postmenopausal women with osteoporosis. The mineral and collagen properties of cortico-cancellous biopsies from the proximal femur were compared in bisphosphonate-naive (-BIS, n = 20) and bisphosphonate-treated (+BIS, n = 20, duration 7 ± 5 y) patients with intertrochanteric (IT) and subtrochanteric (ST) fractures using Fourier transform infrared imaging (FTIRI). The mean values of the FTIRI parameter distributions were similar across groups, but the widths of the parameter distributions tended to be reduced in the +BIS group relative to the -BIS group. Specifically, the distribution widths of the cortical collagen maturity and crystallinity were reduced in the +BIS group relative to those of the -BIS group by 28% (+BIS 0.45 ± 0.18 vs. -BIS 0.63 ± 0.28, p = 0.03) and 17% (+BIS 0.087 ± 0.012 vs. -BIS 0.104 ± 0.036, p = 0.05), respectively. When the tissue properties were examined as a function of fracture morphology within the +BIS group, the FTIR parameters were generally similar regardless of fracture morphology. However, the cortical mineral:matrix ratio was 8% greater in tissue from patients with atypical ST fractures (n =6) than that of patients with typical (IT or spiral ST) fractures (n = 14) (Atypical 5.6 ± 0.3 vs. Typical 5.2 ± 0.5, p = 0.03). Thus, although the mean values of the FTIR properties were similar in both groups, the tissue in bisphosphonate-treated patients had a more uniform composition than that of bisphosphonate-naïve patients. The observed reductions in mineral and matrix heterogeneity may diminish tissue-level toughening mechanisms. © 2011 American Society for Bone and Mineral Research
Fourier transform infrared imaging; cortical bone; material properties; hip fracture; atypical subtrochanteric fracture
Donnelly Research Lab 
You must be logged in to post a comment.