Bone density and geometric properties of the distal radius in displaced and undisplaced Colles' fractures: Quantitative CT in 70 women

We examined cortical and trabecular bone density and geometric properties of the unfractured distal radius in 70 women with recent Colles' fractures, using multilayer peripheral quantitative computed tomography (pQCT). We found that cortical volumetric density, cortical area and mean cortical thickness were lower in the displaced than in the undisplaced fractures, suggesting that the cross-sectional volumetric density and geometric properties of cortical bone may be essential in determining the severity of a Colles' fracture. We also compared lumbar spine and femoral neck bone mineral density (BMD) and the occurrence of osteoporosis in the displaced and undisplaced fracture groups and found no significant difference, which suggests that displacement of a Colles' fracture is not associated with general osteoporosis.     

Bone density and geometric properties of the distal radius in displaced and undisplaced Colles' fractures: quantitative CT in 70 women

We examined cortical and trabecular bone density and geometric properties of the unfractured distal radius in 70 women with recent Colles' fractures, using multilayer peripheral quantitative computed tomography (pQCT). We found that cortical volumetric density, cortical area and mean cortical thickness were lower in the displaced than in the undisplaced fractures, suggesting that the cross-sectional volumetric density and geometric properties of cortical bone may be essential in determining the severity of a Colles' fracture. We also compared lumbar spine and femoral neck bone mineral density (BMD) and the occurrence of osteoporosis in the displaced and undisplaced fracture groups and found no significant difference, which suggests that displacement of a Colles' fracture is not associated with general osteoporosis.     

Lower hip bone mass and proximal femur fractures in elderly patients: more valuable than lumbar vertebrae bone mineral density

A decreased bone mineral density, such as osteoporosis, has been considered a factor closely associated with proximal femur fractures. We studied the relationship between osteoporosis and proximal femur fractures. Dual energy radiograph absorptiometry was used to measure the bone mineral density of 121 patients with a femur neck fracture and 134 patients with an intertrochanteric fracture. The bone density of the femoral neck, Ward's triangle, and the trochanteric region were measured. Two hundred seventeen normal patients who had undergone a bone mineral density test and were found to have no proximal femur fracture were used as the control group. Comparative analysis was performed after the patients were subdivided into different groups depending on sex and fracture type. The bone mineral density of the lumbar vertebra in patients with a proximal femur fracture was not significantly different from that of the control group, but the bone mineral density of the proximal femur in patients with a proximal femur fracture was significantly less than that of the control group. The bone mineral density of the group with an intertrochanteric fracture was lower than that of the femur neck fracture group. However, the difference was statistically insignificant. In bone mineral density comparisons, no significant differences were observed between the displaced and undisplaced femur neck fracture group and between the stable and the unstable intertrochanteric fracture group. The bone mineral density of elderly patients with a proximal femur fracture was significantly less than that of normal individuals. However, femur neck fractures in elderly men were less likely to be associated with a decreased bone mineral density. Little correlation between bone mineral densities of the proximal femur and fracture location (neck vs intertrochanter) and type (nondisplaced vs displaced neck, stable vs unstable intertrochanter) was found.     

Spatial Differences in the Distribution of Bone Between Femoral Neck and Trochanteric Fractures

There is little knowledge about the spatial distribution differences in volumetric bone mineral density and cortical bone structure at the proximal femur between femoral neck fractures and trochanteric fractures. In this case‐control study, a total of 93 women with fragility hip fractures, 72 with femoral neck fractures (mean ± SD age: 70.6 ± 12.7 years) and 21 with trochanteric fractures (75.6 ± 9.3 years), and 50 control subjects (63.7 ± 7.0 years) were included for the comparisons. Differences in the spatial distributions of volumetric bone mineral density, cortical bone thickness, cortical volumetric bone mineral density, and volumetric bone mineral density in a layer adjacent to the endosteal surface were investigated using voxel‐based morphometry (VBM) and surface‐based statistical parametric mapping (SPM). We compared these spatial distributions between controls and both types of fracture, and between the two types of fracture. Using VBM, we found spatially heterogeneous volumetric bone mineral density differences between control subjects and subjects with hip fracture that varied by fracture type. Interestingly, femoral neck fracture subjects, but not subjects with trochanteric fracture, showed significantly lower volumetric bone mineral density in the superior aspect of the femoral neck compared with controls. Using surface‐based SPM, we found that compared with controls, both fracture types showed thinner cortices in regions in agreement with the type of fracture. Most outcomes of cortical and endocortical volumetric bone mineral density comparisons were consistent with VBM results. Our results suggest: 1) that the spatial distribution of trabecular volumetric bone mineral density might play a significant role in hip fracture; 2) that focal cortical bone thinning might be more relevant in femoral neck fractures; and 3) that areas of reduced cortical and endocortical volumetric bone mineral density might be more relevant for trochanteric fractures in Chinese women. © 2017 American Society for Bone and Mineral Research.     

Risk Factors for Severity and Type of the Hip Fracture

More severe hip fractures such as displaced femoral neck (FN) fractures and unstable intertrochanteric (IT) fractures lead to poorer outcomes, but risk factors for severe fractures have not been studied. To identify risk factors for severe types of hip fracture, we performed a prospective cohort study and obtained preoperative hip radiographs from women who sustained an incident hip fracture (excluding traumatic fractures). A single radiologist scored the severity of FN fractures by the Garden System: grades I and II, undisplaced; grades III and IV, displaced. The severity of IT hip fractures was rated by the Kyle System: grades I and II, stable; grades III and IV, unstable. A total of 249 women had FN fractures: 75 (30%) were undisplaced. A total of 213 women had IT fractures: 59 (28%) were stable. Both types of hip fracture increased with age, but older age was even more strongly associated with more severe hip fractures. Low BMD was more strongly related to undisplaced FN fractures (p interaction BMD × FN type, p = 0.0008) and stable IT fractures (p interaction BMD × IT type, p = 0.04). Similar findings were observed for estimated volumetric BMD and hip geometric parameters. Corticosteroid use was only associated with displaced FN fractures, and Parkinson's disease was only associated with stable IT fractures. Little difference was reported in the self‐reported circumstances surrounding each type of fracture. In conclusion, the lower the BMD, the greater the likelihood of experiencing a hip fracture that is less displaced and more stable.     

Skeletal Structure in Postmenopausal Women With Osteopenia and Fractures Is Characterized by Abnormal Trabecular Plates and Cortical Thinning

The majority of fragility fractures occur in women with osteopenia rather than osteoporosis as determined by dual‐energy X‐ray absorptiometry (DXA). However, it is difficult to identify which women with osteopenia are at greatest risk. We performed this study to determine whether osteopenic women with and without fractures had differences in trabecular morphology and biomechanical properties of bone. We hypothesized that women with fractures would have fewer trabecular plates, less trabecular connectivity, and lower stiffness. We enrolled 117 postmenopausal women with osteopenia by DXA (mean age 66 years; 58 with fragility fractures and 59 nonfractured controls). All had areal bone mineral density (aBMD) measured by DXA. Trabecular and cortical volumetric bone mineral density (vBMD), trabecular microarchitecture, and cortical porosity were measured by high‐resolution peripheral computed tomography (HR‐pQCT) of the distal radius and tibia. HR‐pQCT scans were subjected to finite element analysis to estimate whole bone stiffness and individual trabecula segmentation (ITS) to evaluate trabecular type (as plate or rod), orientation, and connectivity. Groups had similar age, race, body mass index (BMI), and mean T‐scores. Fracture subjects had lower cortical and trabecular vBMD, thinner cortices, and thinner, more widely separated trabeculae. By ITS, fracture subjects had fewer trabecular plates, less axially aligned trabeculae, and less trabecular connectivity. Whole bone stiffness was lower in women with fractures. Cortical porosity did not differ. Differences in cortical bone were found at both sites, whereas trabecular differences were more pronounced at the radius. In summary, postmenopausal women with osteopenia and fractures had lower cortical and trabecular vBMD; thinner, more widely separated and rodlike trabecular structure; less trabecular connectivity; and lower whole bone stiffness compared with controls, despite similar aBMD by DXA. Our results suggest that in addition to trabecular and cortical bone loss, changes in plate and rod structure may be important mechanisms of fracture in postmenopausal women with osteopenia. © 2014 American Society for Bone and Mineral Research.     

Varus deformity following lateral humeral condylar fractures in children

Lateral humeral condylar fractures are quite common in children. This article shows that varus deformity is a common sequela following such injuries. Twenty-four patients were studied, with a mean follow-up of 4.8 years. A loss of carrying angle, seen in 10 cases, occurred with comparable frequency in undisplaced (50%) and displaced (39%) fractures. The deformity was usually mild, averaging 10 degrees in the undisplaced fractures and 9.6 degrees in the displaced fractures treated with open reduction. We conclude that varus deformity is common in this injury, and occurs whether or not the fracture is displaced.     

Transcondylar fractures of the distal humerus

We classify transcondylar fractures of the distal humerus into four groups: undisplaced; simple displaced; T-type; and fracture dislocations (Posada's fracture). Our treatment of these fractures is based upon this classification. Undisplaced fractures are treated with immobilization. Displaced fractures are reduced and stabilized with internal fixation. Stabilization of these fractures is difficult because the distal fragments are small and a large portion of their surface is covered with articular cartilage. Transposition of the ulnar nerve allows us to use the cubital tunnel as a point for fixation. We found in our series of 11 patients that undisplaced fractures have the best prognosis. However, all of our patients lost elbow motion, particularly extension. Radiographic signs of post-traumatic arthritis were more pronounced in displaced fractures.     

Imaging Technologies for Assessment of Skeletal Health in Men

Conventional radiography can detect most fractures, evaluate their healing, and visualize characteristic skeletal abnormalities for some metabolic bone diseases. Dual-energy X-ray absorptiometry (DXA) is used to measure areal bone mineral density (BMD) in order to diagnose osteoporosis, estimate fracture risk, and monitor changes in BMD over time. Vertebral fracture assessment by DXA can diagnose vertebral fractures with less ionizing radiation, greater patient convenience, and lower cost than conventional radiography. Quantitative computed tomography (QCT) measures volumetric BMD separately in cortical and trabecular bone compartments. High resolution peripheral QCT and high resolution magnetic resonance imaging are noninvasive research tools that assess the microarchitecture of bone. The use of these technologies and others has been associated with special challenges in men compared with women, provided insights into differences in the pathogenesis of osteoporosis in men and women, and enhanced understanding of the mechanisms of action of osteoporosis treatments.     

Outcome of undisplaced and moderately displaced femoral neck fractures

Background The optimal treatment for femoral neck fracture is a matter of controversy. We compared the outcome of displaced fractures with good healing potential (moderately displaced fractures) to the outcome of undisplaced fractures treated by internal fixation with 2 parallel screws.

Methods In a consecutive series of hip fracture patients, the rates of reoperation and mortality for 225 undisplaced fractures were compared to those for 241 moderately displaced fractures. The patients were followed for 1-6 years.

Results The total rate of reoperation was 19% (9% because of healing complications) for the undisplaced fractures and 33% (20% because of healing complications) for the moderately displaced fractures. Fracture displacement was the main predictor of reoperation. There was no difference in mortality between the groups, and patient-related background parameters (rather than fracture displacement) were the main predictors of mortality.

Interpretation Undisplaced fractures should be treated by internal fixation. The best treatment for moderately displaced fractures remains to be determined.     

蛋白质的摄入量及来源对骨密度的影响

中国人口老龄化日趋明显,骨质疏松症及其相关的骨折等并发症患病率急剧上升。蛋白质是除钙和维生素D外,维持骨骼生长发育、力学性能和骨折愈合的重要营养素。研究发现,蛋白质摄入量过多或过少都对骨代谢有不利影响。适当增加蛋白质摄入可以增加全身骨密度,还可预防髋部骨折。素食者和素食主义者股骨颈和腰椎的骨密度低于杂食者,而且素食主义者的骨折率高于杂食者。过多摄入含有酸化氨基酸的动物来源蛋白质(如半胱氨酸和甲硫氨酸)会增加患骨质疏松症的风险。以鱼、橄榄油和低摄入红肉为特征的地中海饮食模式与较高的骨密度有关。因此,适量而均衡的蛋白质摄入有利于骨健康。     

Outcome of undisplaced and moderately displaced femoral neck fractures

Background?The optimal treatment for femoral neck fracture is a matter of controversy. We compared the outcome of displaced fractures with good healing potential (moderately displaced fractures) to the outcome of undisplaced fractures treated by internal fixation with 2 parallel screws.

Methods?In a consecutive series of hip fracture patients, the rates of reoperation and mortality for 225 undisplaced fractures were compared to those for 241 moderately displaced fractures. The patients were followed for 1–6 years.

Results?The total rate of reoperation was 19% (9% because of healing complications) for the undisplaced fractures and 33% (20% because of healing complications) for the moderately displaced fractures. Fracture displacement was the main predictor of reoperation. There was no difference in mortality between the groups, and patient-related background parameters (rather than fracture displacement) were the main predictors of mortality.

Interpretation?Undisplaced fractures should be treated by internal fixation. The best treatment for moderately displaced fractures remains to be determined.     

HR-pQCT based FE analysis of the most distal radius section provides an improved prediction of Colles' fracture load in vitro

The remarkable performances of high-resolution peripheral quantitative computed tomography (HR-pQCT) make the distal radius a favorable site for early diagnosis of osteoporosis and improved Colles' fracture risk assessment. The goal of this study was to investigate if the HR-pQCT-based micro finite element (μFE) method applied on specific sections of the distal radius provides improved predictions of Colles' fracture load in vitro compared to bone mineral content (BMC), bone mineral density (BMD), or histomorphometric indices. HR-pQCT based BMC, BMD, histomorphometric parameters, and μFE models of 9-mm-thick bone sections were used to predict fracture load of 21 distal radii assessed in an experimental model of Colles' fracture reported in a previous study. The analysis was performed on two bone sections: a standard one recommended by the HR-pQCT manufacturer and a second one defined just proximal to the distal subchondral plate. For most of the investigated parameters, significant differences were found between the values of the two sections. Correlations with experimental fracture load and strength were higher in the most distal section, and the difference was statistically significant for μFE strength. Furthermore, the most distal section was computed to have significantly lower ultimate force and strength by 13% and 35%, respectively, than the standard section. BMC provided a better estimation of Colles' fracture load (R² = 0.942) than aBMD or any other histomorphometric indices. The best prediction was achieved with μFE analyses of the most distal slice (R² = 0.962), which provided quantitatively correct ultimate forces.     

Geometric properties of distal radius and pathogenesis of Colles fracture: a peripheral quantitative computed tomography study.

It is well known among clinicians that Colles fracture patients may have normal projected axial bone mineral density and that bone mass is not synonymous with bone strength. The aim of this work was to investigate whether cross-sectional properties of the distal radius in female patients with recent Colles fracture differ from those of a younger group of normal women without fracture. It was hypothesized that patients with Colles fracture had petite distal radii and that cortical thinning and reduced cortical and trabecular volumetric density are dominant features of this fracture type. We used a multilayer high-precision peripheral quantitative computed tomography (pQCT) device with a long-term precision error of 0.1% for a dedicated phantom during the measurement period (152 d). Clinical measurements were made at an ultradistal site rich in trabecular bone and a less ultradistal site rich in cortical bone. The results show that the following pQCT variables were significantly reduced in the nonfractured radius of the Colles fracture cases: mean ultradistal trabecular volumetric density, mean ultradistal and distal cortical volumetric density, mean ultradistal and distal cortical thickness (p < 0.001 for all differences). The outer cortical diameter, cross-sectional bone area, and cortical bending moment of inertia were not statistically different in the two groups. Thus, it would appear that Colles fracture cases did not have petite distal radii. The results suggest that the deforming force of Colles fracture has a transaxial direction (fall on outstretched arm), resulting in a crush fracture, and that it is not a bending force. We suggest that Colles fracture occurs as a result of the combined effect of a fall on the out-stretched arm, low trabecular and cortical volumetric bone density, and reduced cortical thickness.     

Ipsilateral fractures of the distal radius and scaphoid treated by Herbert screw and external skeletal fixation. A report of two cases.

Two patients with comminuted, displaced fractures of the distal radius associated with ipsilateral, undisplaced scaphoid fractures were treated by internal fixation of the scaphoid fracture with a Herbert screw in association with external fixation of the distal radial fracture. One of the patients had a limited open reduction of the distal radius combined with bone grafting. Both patients had satisfactory results. Internal fixation of the scaphoid is indicated if distraction is applied to the carpus to treat an associated fracture of the distal radius, even if the scaphoid fracture is undisplaced.     

The two-level ulnar collateral ligament injury of the metacarpophalangeal joint of the thumb

Ulnar collateral ligament injuries of the thumb may present as avulsion fractures of the bone or as ligamentous tears. Displaced fracture fragments or Stener lesions demand operative management. Occasionally, both fracture and ligamentous tears may occur simultaneously, and the management of the ligamentous aspect may be overlooked in cases with undisplaced fractures leading to failure of non-operative treatment. It is important in cases with a relatively undisplaced fracture fragment to exclude a simultaneous ligamentous tear and Stener lesion by careful clinical examination and by examining the radiographs for telltale displaced flecks of bone.     

Measurement of blood flow in tibial fracture patients using positron emission tomography.

The quantification of local bone blood flow in man has not previously been possible, despite its importance in the study of normal and pathological bone. We report the use of positron emission tomography, using 15O-labelled water, to measure bone blood flow in patients with closed unilateral fractures of the tibia. We compared fractured and unfractured limbs; alterations in blood flow paralleled those found in animal models. There was increased tibial blood flow at the fracture site as early as 24 hours after fracture, reaching up to 14 times that in the normal limb at two weeks. Blood flow increase was less in displaced than in undisplaced fractures. The muscle to bone ratios of blood flow were similar to those in previous animal work using other techniques. Positron emission tomography will allow study of human bone blood flow in vivo in a wide variety of pathological conditions.     

Maternal History of Osteoporosis and Femur Geometry

Most studies that have examined the role of skeletal factors in the relationship between an individual's family history of fracture or osteoporosis and their fracture risk have focused on bone density. In this study, we expanded the scope of skeletal factors to include geometric properties (subperiosteal width, section modulus, cortical thickness, and buckling ratio) in addition to areal bone mineral density (BMD). We compared these skeletal factors at the femur neck and shaft by self-reported maternal history of osteoporosis (OP HX) from 5334 non-Hispanic whites, ages > or =20 years in the Third National Health and Nutrition Examination Survey (NHANES III, 1988-94). A total of 213 men and 315 women reported a positive OP HX (e.g., their biological mother had sustained a hip fracture after age 50 years or had a physician's diagnosis of osteoporosis). Differences in bone density and geometry by OP HX were examined after adjusting for potential confounding variables. Several bone parameters differed significantly by OP HX in both sexes at the femur neck, but none differed at the femur shaft. At the neck, those with a positive OP HX had values that differed by approximately 3% to 4% (lower for BMD, bone mineral content (BMC), cross-sectional area, and cortical thickness; higher for buckling ratios) from those with a negative OP HX (P < 0.05). The magnitude of these relationships was similar in both sexes, but differences were greater in younger versus older adults. In conclusion, both men and women with a positive maternal history of osteoporosis may be at greater risk of femur neck fracture owing to thinner cortices and lower BMC, which in turn results in potentially greater cortical instability (buckling ratio) at this skeletal site.     

Finite Element Analysis Based on In Vivo HR‐pQCT Images of the Distal Radius Is Associated With Wrist Fracture in Postmenopausal Women

BMD, bone microarchitecture, and bone mechanical properties assessed in vivo by finite element analysis were associated with wrist fracture in postmenopausal women. Introduction: Many fractures occur in individuals with normal BMD. Assessment of bone mechanical properties by finite element analysis (FEA) may improve identification of those at high risk for fracture. Materials and Methods: We used HR‐pQCT to assess volumetric bone density, microarchitecture, and μFE‐derived bone mechanical properties at the radius in 33 postmenopausal women with a prior history of fragility wrist fracture and 33 age‐matched controls from the OFELY cohort. Radius areal BMD (aBMD) was also measured by DXA. Associations between density, microarchitecture, mechanical parameters and fracture status were evaluated by univariate logistic regression analysis and expressed as ORs (with 95% CIs) per SD change. We also conducted a principal components (PCs) analysis (PCA) to reduce the number of parameters and study their association (OR) with wrist fracture. Results: Areal and volumetric densities, cortical thickness, trabecular number, and mechanical parameters such as estimated failure load, stiffness, and the proportion of load carried by the trabecular bone at the distal and proximal sites were associated with wrist fracture (p < 0.05). The PCA revealed five independent components that jointly explained 86.2% of the total variability of bone characteristics. The first PC included FE‐estimated failure load, areal and volumetric BMD, and cortical thickness, explaining 51% of the variance with an OR for wrist fracture = 2.49 (95% CI, 1.32–4.72). Remaining PCs did not include any density parameters. The second PC included trabecular architecture, explaining 12% of the variance, with an OR = 1.82 (95% CI, 0.94–3.52). The third PC included the proportion of the load carried by cortical versus trabecular bone, assessed by FEA, explaining 9% of the variance, and had an OR = 1.61 (95% CI, 0.94–2.77). Thus, the proportion of load carried by cortical versus trabecular bone seems to be associated with wrist fracture independently of BMD and microarchitecture (included in the first and second PC, respectively). Conclusions: These results suggest that bone mechanical properties assessed by μFE may provide information about skeletal fragility and fracture risk not assessed by BMD or architecture measurements alone and are therefore likely to enhance the prediction of wrist fracture risk.     

Quality of life related to fracture displacement among elderly patients with femoral neck fractures treated with internal fixation.

OBJECTIVE: To determine differences in outcome between undisplaced (Garden I and II) and displaced (Garden III and IV) femoral neck fractures in elderly patients treated with internal fixation. SETTING: University hospital. DESIGN: Prospective clinical study. PATIENTS: Ninety patients with an acute femoral neck fracture after a fall. The inclusion criteria were age older than sixty-five years, absence of severe cognitive dysfunction, independent living, and unhindered walking capability preoperatively. The mean follow-up was twenty-six months. INTERVENTION: The patients were treated with closed reduction and percutaneous internal fixation with two cannulated screws. MAIN OUTCOME MEASUREMENTS: Fracture healing complications, pain (visual analogue scale), walking capability, activities of daily living, and quality of life according to EuroQol. RESULTS: The rate of fracture healing complications in displaced femoral neck fractures in patients available at the final follow-up was 36 percent compared with 7 percent in patients with undisplaced fractures. The quality of life, according to EuroQol, of patients with uneventfully healed fractures was significantly lower in patients with primarily displaced fractures (0.51) than in patients with undisplaced ones (0.76). CONCLUSION: There was a major difference in outcome on comparing undisplaced and displaced femoral neck fractures in elderly patients treated with internal fixation. The rate of fracture healing complications in patients with undisplaced fractures was low, and patients with healed fractures regained their prefracture quality of life level. The rate of fracture healing complications and reoperations in patients with displaced fractures was high, and even in patients with uneventfully healed fractures, there was a substantial decrease in the quality of life.