Dataset Information

Combination of nanoindentation and quantitative backscattered electron imaging revealed altered bone material properties associated with femoral neck fragility.

ABSTRACT: Osteoporotic fragility fractures were hypothesized to be related to changes in bone material properties and not solely to reduction in bone mass. We studied cortical bone from the superior and inferior sectors of whole femoral neck sections from five female osteoporotic hip fracture cases (74-92 years) and five nonfractured controls (75-88 years). The typical calcium content (Ca(Peak)) and the mineral particle thickness parameter (T) were mapped in large areas of the superior and inferior regions using quantitative backscattered electron imaging (qBEI) and scanning small-angle X-ray scattering, respectively. Additionally, indentation modulus (E) and hardness (H) (determined by nanoindentation) were compared at the local level to the mineral content (Ca(Ind)) at the indent positions (obtained from qBEI). Ca(Peak) (-2.2%, P = 0.002), Ca(Ind) (-1.8%, P = 0.048), E (-5.6%, P = 0.040), and H (-6.0%, P = 0.016) were significantly lower for the superior compared to the inferior region. Interestingly, Ca(Peak) as well as Ca(Ind) were also lower (-2.6%, P = 0.006, and -3.7%, P = 0.002, respectively) in fracture cases compared to controls, while E and H did not show any significant reduction. T values were in the normal range, independent of region (P = 0.181) or fracture status (P = 0.551). In conclusion, it appears that the observed femoral neck fragility is associated with a reduced mineral content, which was not accompanied by a reduction in stiffness and hardness of the bone material. This pilot study suggests that a stiffening process in the organic matrix component contributes to bone fragility independently of mineral content.

SUBMITTER: Fratzl-Zelman N

PROVIDER: S-EPMC2759010 | biostudies-other | 2009 Oct

REPOSITORIES: biostudies-other

ACCESS DATA

Similar Datasets

Project description:AimsTo determine differences in hip geometry in adults with type 1 diabetes (T1D) compared with healthy adults without diabetes.MethodsIn this cross-sectional study, 43 adults with T1D (mean age 56 years, 84 % female, 92 % White, mean duration of diabetes of 39 years, A1c of 7.8 %) and 40 adults without diabetes (mean age 60 years, 80 % female, 77 % white) who had hip dual-energy x-ray absorptiometry (DXA) scans from previous studies were included. Areal bone mineral density (aBMD) and measures of hip structural properties at the narrow neck, intertrochanteric and femoral shaft regions of the left proximal femur were analyzed between adults with T1D and controls using linear models controlled for age, sex, and body mass index.ResultsThere were no significant differences in DXA-based aBMD at the hip (0.769 ± 0.132 vs. 0.900 ± 0.139 g/cm2, p = 0.07) or femoral neck (0.722 ± 0.116 vs. 0.849 ± 0.114 g/cm2, p = 0.09) regions between adults with T1D and controls. When controlling for age, sex, and BMI, DXA-based aBMD at the hip (0.880 ± 0.022 vs. 0.943 ± 0.020 g/cm2, p = 0.02) and femoral neck (0.750 ± 0.021 vs. 0.812 ± 0.020 g/cm2, p = 0.02) regions were significantly lower in adults with T1D than controls. Cortical thickness was significantly lower in all three hip regions in adults with T1D than in controls (narrow-neck: 0.169 ± 0.005 vs. 0.186 ± 0.005 cm, p = 0.011; intertrochanteric: 0.388 ± 0.013 vs. 0.425 ± 0.012 cm, p = 0.017; femoral shaft: 0.529 ± 0.017 vs. 0.586 ± 0.016 cm, p = 0.006). Moreover, adults with T1D had a smaller cross-sectional area at the narrow-neck (3.06 ± 0.09 vs. 3.32 ± 0.08 cm2, p = 0.015), a higher femoral shaft endocortical diameter (2.23 ± 0.07 vs. 2.02 ± 0.06 cm, p = 0.011), and higher buckling ratios (an indicator of cortical instability) at the intertrochanteric (9.22 ± 0.34 vs. 8.23 ± 0.32, p = 0.016) and femoral shaft (3.32 ± 0.15 vs. 2.89 ± 0.14, p = 0.016) regions.ConclusionsAdults with T1D have several significant differences in proximal femur morphology compared with controls. These morphological differences may adversely affect the mechanical integrity of the proximal femur, thereby contributing to an increased risk of fracture in the event of a fall.

Project description:ObjectiveTo investigate the effects of postoperative femoral neck shortening in patients with femoral neck fractures fixed with femoral neck system screws (FNS) and to explore the factors influencing femoral neck shortening.MethodTo retrospectively analyze the data of 113 patients with femoral neck fractures admitted to the Second Hospital of Fuzhou City, affiliated with Xiamen University, between December 2019 and January 2022. Of these, 87 patients were followed up for more than 12 months, 49 men and 38 women: 36 cases of Garden I and II fractures and 51 cases of Garden III and IV fractures, to record the patient's hip Harris score at 12 months postoperatively. Patients were divided into femoral neck shortening group and femoral neck no shortening group according to their regular postoperative follow-up radiographic measurements. To count the incidence of femoral neck shortening, a comparison of postoperative complication rates and hip Harris scores between the two groups was made. Statistical comparison of the two groups and a multifactorial logistic regression analysis were also performed to analyze the factors affecting femoral neck shortening.ResultsAll 87 patients were followed up for more than 12 months after surgery. In 34 of these cases, neck shortening occurred, and the incidence rate was 39.1%. 15 cases of severe shortening, incidence of 17.2%; fracture healing 84 cases, fracture healing rate of 96.5%. The hip Harris score was 83.99 (81.95, 89.20) in the neck shortening group at 12 months postoperatively, 90.87 (87.95, 94.80) for the group without neck shortening; the difference between the two groups was statistically significant (P < 0.01). 32 cases of fracture healing in the neck shortening group at 12 months after surgery, fracture healing rate of 94.1%; 52 cases healed without neck shortening group, fracture healing rate of 98.1%. The difference between the two groups was not statistically significant (P = 0.337). High incidence of neck shortening after FNS fixation of femoral neck fractures, cortical comminution of the severed end, fracture fractionation and quality of reduction were significantly correlated with neck shortening.ConclusionHigh incidence of postoperative neck shortening after internal fixation of femoral neck fractures with the femoral neck system, the cortical comminution, the type of fracture, and the quality of fracture reduction are the influencing factors; femoral neck shortening can affect postoperative hip function, but does not affect fracture healing.

Project description:ObjectiveThis meta-analysis aimed to compare the relative safety and efficacy of cannulated compression screw (CCS) and femoral neck system (FNS) in treating patients with femoral neck fractures and to provide evidence-based medical evidence for FNS in treating femoral neck fractures.MethodsPubMed, Embase, Cochrane, and China National Knowledge Infrastructure databases were searched to collect outcomes related to femoral neck fractures treated with FNS and CCS, including time to fracture healing, incidence of non-union, incidence of osteonecrosis of the femoral head, incidence of failure of internal fixation, rate of femoral neck shortening, Harris hip score, Barthel index, operative time, intraoperative blood loss, fluoroscopy frequency, and complications. A meta-analysis was performed using RevManv5.4 (The Cochrane Collaboration) and Stata v14.0 software.ResultsThis analysis included 21 studies involving 1,347 patients. The results showed that FNS was superior to CCS in terms of fracture healing time [mean difference (MD) = -0.75, 95% CI = (-1.04, -0.46), P < 0.05], incidence of bone non-union [odds ratio (OR) = 0.53, 95% CI = (0.29, 0.98), P = 0.04], incidence of osteonecrosis of the femoral head [OR = 0.49, 95% CI = (0.28, 0.86), P = 0.01], incidence of internal fixation failure [OR = 0.30, 95% CI = (0.18, 0.52), P < 0.05], rate of femoral neck shortening [OR = 0.38, 95% CI = (0.27, 0.54), P > 0.05], Harris hip score [MD = 3.31, 95% CI = (1.99, 4.63), P < 0.001], Barthel index [MD = 4.31, 95% CI = (3.02, 5.61), P < 0.05], intraoperative bleeding [MD = 14.72, 95% CI = (8.52, 20.92), P < 0.05], fluoroscopy frequency [OR = 0.53, 95% CI = (0.29, 0.98), P = 0.04], and complications [OR = 0.31, 95% CI = (0.22, 0.45), P < 0.05]. The difference between FNS and CCS in operative time was not statistically significant [MD = -2.41, 95% CI = (-6.88, 2.05), P = 0.29].ConclusionFNS treatment of femoral neck fracture can shorten the fracture healing time; reduce the incidence and translucent rate of bone non-union, osteonecrosis of the femoral head, and internal fixation failure; reduce intraoperative blood loss and postoperative complications; and improve hip joint function and activity. We are confident in the findings that FNS, an effective and safe procedure for internal fixation of femoral neck fractures, is superior to CCS.

Dataset Information

Combination of nanoindentation and quantitative backscattered electron imaging revealed altered bone material properties associated with femoral neck fragility.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets