Comparison of non-invasive assessments of strength of the proximal femur

Jóhannesdóttir, Fjóla; Thrall, Erica; Muller, John A.; Keaveny, Tony M.; Kopperdahl, David L.; Bouxsein, Mary L.

doi:10.1016/j.bone.2017.07.023

Cited by 79 publications

(74 citation statements)

References 68 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Both treated and control femurs were tested to failure in a sideways fall configuration, as previously reported. 29 In brief, the greater trochanter and femoral head were partially embedded in urethane as described above, which was custom fit for each specimen. Mechanical testing was performed using a servohydraulic load frame (MTS Systems 810, Eden Prairie, MN).…”

Section: Mechanical Testing In Sideways Fall Configurationmentioning

confidence: 99%

In vitro injection of osteoporotic cadaveric femurs with a triphasic calcium‐based implant confers immediate biomechanical integrity

Stroncek¹,

Shaul²,

Favell³

et al. 2019

Journal Orthopaedic Research

Self Cite

View full text Add to dashboard Cite

Current pharmaceutical therapies can reduce hip fractures by up to 50%, but compliance to treatment is low and therapies take up to 18 months to reduce risk. Thus, alternative or complementary approaches to reduce the risk of hip fracture are needed. The AGN1 local osteo‐enhancement procedure (LOEP) is one such alternative approach, as it is designed to locally replace bone lost due to osteoporosis and provide immediate biomechanical benefit. This in vitro study evaluated the initial biomechanical impact of this treatment on human cadaveric femurs. We obtained 45 pairs of cadaveric femurs from women aged 77.8 ± 8.8 years. One femur of each pair was treated, while the contralateral femur served as an untreated control. Treatment included debridement, irrigation/suction, and injection of a triphasic calcium‐based implant (AGN1). Mechanical testing of the femora was performed in a sideways fall configuration 24 h after treatment. Of the 45 pairs, 4 had normal, 16 osteopenic, and 25 osteoporotic BMD T‐scores. Altogether, treatment increased failure load on average by 20.5% ( p < 0.0001). In the subset of osteoporotic femurs, treatment increased failure load by 26% and work to failure by 45% ( p < 0.01 for both). Treatment did not significantly affect stiffness in any group. These findings provide evidence that local delivery of the triphasic calcium‐based implant in the proximal femur is technically feasible and provides immediate biomechanical benefit. Our results provide strong rationale for additional studies investigating the utility of this approach for reducing the risk of hip fracture. © 2019 The Authors. Journal of Orthopaedic Research ® Published by Wiley Periodicals, Inc. on behalf of Orthopaedic Research Society.

show abstract

Section: Mechanical Testing In Sideways Fall Configurationmentioning

confidence: 99%

In vitro injection of osteoporotic cadaveric femurs with a triphasic calcium‐based implant confers immediate biomechanical integrity

Stroncek¹,

Shaul²,

Favell³

et al. 2019

Journal Orthopaedic Research

Self Cite

View full text Add to dashboard Cite

show abstract

“…And finally, via non‐linear finite element analysis, virtual loads applied to the bone are gradually increased until the bone begins to break, thus providing an estimate of the breaking strength of the femur (defined as the force, in units of newtons, at an overall deformation of 4.0% strain). This approach has been validated against cadaver strength measurements …”

Section: Methodsmentioning

confidence: 82%

“…This approach has been validated against cadaver strength measurements. (29) The VirtuOst-based BCT analysis used in FOCUS also provides DXA-equivalent BMD T-scores at the hip. (14,15,17,20,28) In two prior studies (14,15) that analyzed previously taken routine clinical CT scans in which the BCT measurements were blinded to the DXA data, the femoral neck BMD T-scores from VirtuOst agreed well with those from DXA.…”

Section: Bct Analysismentioning

confidence: 99%

Osteoporosis and Hip Fracture Risk From Routine Computed Tomography Scans: The Fracture, Osteoporosis, and CT Utilization Study (FOCUS)

Adams

Fischer

Kopperdahl

et al. 2018

Journal of Bone and Mineral Research

View full text Add to dashboard Cite

Methods now exist for analyzing previously taken clinical computed tomography (CT) scans to measure a dual-energy X-ray absorptiometry (DXA)-equivalent bone mineral density (BMD) at the hip and a finite element analysis-derived femoral strength. We assessed the efficacy of this "biomechanical CT" (BCT) approach for identifying patients at high risk of incident hip fracture in a large clinical setting. Using a case-cohort design sampled from 111,694 women and men aged 65 or older who had a prior hip CT scan, a DXA within 3 years of the CT, and no prior hip fracture, we compared those with subsequent hip fracture (n = 1959) with randomly selected sex-stratified controls (n = 1979) and analyzed their CT scans blinded to all other data. We found that the age-, race-, and body mass index (BMI)-adjusted hazard ratio (HR; per standard deviation) for femoral strength was significant before (women: HR = 2.8, 95% confidence interval [CI] 2.2-3.5; men: 2.8, 2.1-3.7) and after adjusting also for the (lowest) hip BMD T-score by BCT (women: 2.1, 1.4-3.2; men: 2.7, 1.6-4.6). The hazard ratio for the hip BMD T-score was similar between BCT and DXA for both sexes (women: 2.1, 1.8-2.5 BCT versus 2.1, 1.7-2.5 DXA; men: 2.8, 2.1-3.8 BCT versus 2.5, 2.0-3.2 DXA) and was higher than for the (lowest) spine/hip BMD T-score by DXA (women: 1.6, 1.4-1.9; men: 2.1, 1.6-2.7). Compared with the latter as a clinical-practice reference and using both femoral strength and the hip BMD T-score from BCT, sensitivity for predicting hip fracture was higher for BCT (women: 0.66 versus 0.59; men: 0.56 versus 0.48), with comparable respective specificity (women: 0.66 versus 0.67; men: 0.76 versus 0.78). We conclude that BCT analysis of previously acquired routine abdominal or pelvic CT scans is at least as effective as DXA testing for identifying patients at high risk of hip fracture. © 2018 American Society for Bone and Mineral Research.

show abstract

“…The hip is considered a cortical bone site, but both cortical and trabecular bone contribute to femoral strength, the contribution of the cortical bone being higher in femurs with lower trabecular bone density [2]. Furthermore, the cortical bone supports bending in the distal region of the femoral neck and the trabecular bone supports the proximal load.…”

mentioning

confidence: 99%