@article{GroteNoeldekeBlauthetal.2013,
  author    = {Grote, Stefan and Noeldeke, Tatjana and Blauth, Michael and Mutschler, Wolf and B{\"u}rklein, Dominik},
  title     = {Mechanical torque measurement in the proximal femur correlates to failure load and bone mineral density ex vivo},
  series = {Orthopedic Reviews (Pavia)},
  volume    = {5},
  journal   = {Orthopedic Reviews (Pavia)},
  number    = {e16},
  doi       = {10.4081/or.2013.e16},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-132358},
  year      = {2013},
  abstract  = {Knowledge of local bone quality is essential for surgeons to determine operation techniques. A device for intraoperative measurement of local bone quality has been developed by the AO-Research Foundation (DensiProbe®). We used this device to experimentally measure peak breakaway torque of trabecular bone in the proximal femur and correlated this with local bone mineral density (BMD) and failure load. Bone mineral density of 160 cadaver femurs was measured by ex situ dual-energy X-ray absorptiometry. The failure load of all femurs was analyzed by side-impact analysis. Femur fractures were fixed and mechanical peak torque was measured with the DensiProbe® device. Correlation was calculated whereas correlation coefficient and significance was calculated by Fisher's Z-transformation. Moreover, linear regression analysis was carried out. The unpaired Student's t-test was used to assess the significance of differences. The Ward triangle region had the lowest BMD with 0.511 g/cm2 (±0.17 g/cm2), followed by the upper neck region with 0.546 g/cm2 (±0.16 g/cm2), trochanteric region with 0.685 g/cm2 (±0.19 g/cm2) and the femoral neck with 0.813 g/cm2 (±0.2 g/cm2). Peak torque of DensiProbe® in the femoral head was 3.48 Nm (±2.34 Nm). Load to failure was 4050.2 N (±1586.7 N). The highest correlation of peak torque measured by Densi Probe® and load to failure was found in the femoral neck (r=0.64, P<0.001). The overall correlation of mechanical peak torque with T-score was r=0.60 (P<0.001). A correlation was found between mechanical peak torque, load to failure of bone and BMD in vitro. Trabecular strength of bone and bone mineral density are different aspects of bone strength, but a correlation was found between them. Mechanical peak torque as measured may contribute additional information about bone strength, especially in the perioperative testing.},
  language  = {en}
}
@article{HaringCrandallCarboneetal.2019,
  author    = {Haring, Bernhard and Crandall, Carolyn J and Carbone, Laura and Liu, Simin and Li, Wenjun and Johnson, Karen C and Wactawski-Wende, Jean and Shadyab, Aladdin H and Gass, Margery L and Kamensky, Victor and Cauley, Jane A and Wassertheil-Smoller, Sylvia},
  title     = {Lipoprotein(a) plasma levels, bone mineral density and risk of hip fracture: a post hoc analysis of the Women's Health Initiative, USA},
  series = {BMJ Open},
  volume    = {9},
  journal   = {BMJ Open},
  doi       = {10.1136/bmjopen-2018-027257},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-201139},
  pages     = {e027257},
  year      = {2019},
  abstract  = {Objectives Elevated Lipoprotein(a) (Lp[a]) is a well-known risk factor for cardiovascular disease. However, its roles in bone metabolism and fracture risk are unclear. We therefore investigated whether plasma Lp(a) levels were associated with bone mineral density (BMD) and incident hip fractures in a large cohort of postmenopausal women. Design Post hoc analysis of data from the Women's Health Initiative (WHI), USA. Setting 40 clinical centres in the USA. Participants The current analytical cohort consisted of 9698 white, postmenopausal women enrolled in the WHI, a national prospective study investigating determinants of chronic diseases including heart disease, breast and colorectal cancers and osteoporotic fractures among postmenopausal women. Recruitment for WHI took place from 1 October 1993 to 31 December 1998. Exposures Plasma Lp(a) levels were measured at baseline. Outcome measures Incident hip fractures were ascertained annually and confirmed by medical records with follow-up through 29 August 2014. BMD at the femoral neck was measured by dual X-ray absorptiometry in a subset of participants at baseline. Statistical analyses Cox proportional hazards and logistic regression models were used to evaluate associations of quartiles of plasma Lp(a) levels with hip fracture events and hip BMD T-score, respectively. Results During a mean follow-up of 13.8 years, 454 incident cases of hip fracture were observed. In analyses adjusting for confounding variables including age, body mass index, history of hysterectomy, smoking, physical activity, diabetes mellitus, general health status, cardiovascular disease, use of menopausal hormone therapy, use of bisphosphonates, calcitonin or selective-oestrogen receptor modulators, baseline dietary and supplemental calcium and vitamin D intake and history of fracture, no significant association of plasma Lp(a) levels with low hip BMD T-score or hip fracture risk was detected. Conclusions These findings suggest that plasma Lp(a) levels are not related to hip BMD T-score or hip fracture events in postmenopausal women.},
  language  = {en}
}