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This study aimed to determine the association between areal and volumetric bone mineral density (BMD) with all-cause mortality in patients with type 2 diabetes (T2D). Associations between BMD and all-cause mortality were examined in 576 women and 517 men with T2D in the Diabetes Heart Study. Volumetric BMD in the thoracic and lumbar spine was measured with quantitative computed tomography. Areal BMD (aBMD) in the lumbar spine, total hip, femoral neck, ultradistal radius, mid radius, and whole body was measured using dual X-ray absorptiometry. Association of BMD with all-cause mortality was determined using sequential models, stratified by sex: (1) unadjusted; (2) adjusted for age, race, smoking, alcohol, estrogen use; (3) model 2 plus history of cardiovascular disease, hypertension, and coronary artery calcification; (4) model 3 plus lean mass; and (5) model 3 plus fat mass. At baseline, mean age was 61.2 years for women and 62.7 years for men. At mean 11.0 ± 3.7 years' follow-up, 221 (36.4%) women and 238 (43.6%) men were deceased. In women, BMD at all skeletal sites (except spine aBMD and whole body aBMD) was inversely associated with all-cause mortality in the unadjusted model. These associations remained significant in the mid radius (hazard ratio per standard deviation = 0.79; p = 0.0057) and distal radius (hazard ratio per standard deviation = 0.76; p = 0.0056) after adjusting for all covariates, including lean mass. In men, volumetric BMD measurements but not aBMD were inversely associated with mortality and only in the unadjusted model. In this longitudinal study, lower baseline aBMD in the radius was associated with increased all-cause mortality in women with T2D, but not men, independent of other risk factors for death.
Copyright © 2017 The International Society for Clinical Densitometry. Published by Elsevier Inc. All rights reserved.
In addition to the loss in bone volume that occurs with age, there is a decline in material properties. To test new therapies or diagnostic tools that target such properties as material strength and toughness, a pre-clinical model of aging would be useful in which changes in bone are similar to those that occur with aging in humans. Toward that end, we hypothesized that similar to human bone, the estimated toughness and material strength of cortical bone at the apparent-level decreases with age in the male Fischer F344 rat. In addition, we tested whether the known decline in trabecular architecture in rats translated to an age-related decrease in vertebra (VB) strength and whether non-X-ray techniques could quantify tissue changes at micron and sub-micron length scales. Bones were harvested from 6-, 12-, and 24-month (mo.) old rats (n=12 per age). Despite a loss in trabecular bone with age, VB compressive strength was similar among the age groups. Similarly, whole-bone strength (peak force) in bending was maintained (femur) or increased (radius) with aging. There was though an age-related decrease in post-yield toughness (radius) and bending strength (femur). The ability to resist crack initiation was actually higher for the 12-mo. and 24-mo. than for 6-mo. rats (notch femur), but the estimated work to propagate the crack was less for the aged bone. For the femur diaphysis region, porosity increased while bound water decreased with age. For the radius diaphysis, there was an age-related increase in non-enzymatic and mature enzymatic collagen crosslinks. Raman spectroscopy analysis of embedded cross-sections of the tibia mid-shaft detected an increase in carbonate subsitution with advanced aging for both inner and outer tissue.
Published by Elsevier Inc.
BACKGROUND - Concomitant ipsilateral hip and distal radius fractures are uncommon, and little research has been published about these injuries. Our aim was to evaluate the characteristics and results of treatment for these injuries.
METHODS - Between 2006 and 2012, 35 concomitant hip and distal radius fractures were identified, comprising the study group. The characteristics and results of treatment for these injuries were evaluated and analyzed. Another matched control group with isolated hip fractures was collected for comparison of patient characteristics, fall mechanism, fracture pattern, bone density, and functional recovery.
RESULTS - For the patients with concomitant fractures, the average age was 77.6 years, and the female-to-male ratio was 6:1 (30:5). The majority (91.4%) of patients sustained ipsilateral injuries. Among the controlled pairs, 20 (57.1%) patients in the study group sustained a backward fall, and 25 (71.4%) patients in the control group had a sideways fall. With respect to the pattern of hip fracture, 22 (62.9%) patients in the study group had femoral neck fractures and 20 (57.1%) patients in the control group had pertrochanteric fractures. The average hospital stay was 15.3 days in the study group versus 10.2 days in the control group. Twenty-five (71.4%) patients in the study group and 27 (77.1%) patients in the control group had osteoporosis. The average Barthel index score was 75.1 in the study group and 75.7 in the control group.
CONCLUSION - Concomitant hip and distal radius fractures were generally ipsilateral and involved the femoral neck after a backward fall. These patients were younger than and not more osteoporotic than the population with isolated hip fractures; however, the hospital stay was significantly increased. The functional outcome was not influenced by concomitant wrist fracture.
Copyright © 2014. Published by Elsevier Taiwan.
BACKGROUND - The prevalence and cost of unnecessary advanced imaging studies (AIS) in the evaluation of long bone cartilaginous lesions have not been studied previously.
METHODS - A total of 105 enchondromas and 19 chondrosarcomas arising in long bones from July 2008 until April 2012 in 121 patients were reviewed. Advanced imaging was defined as MRI, CT, bone scan, skeletal survey, or CT biopsy. Two blinded radiologists independently reviewed the initial imaging study and determined if further imaging was indicated based on that imaging study alone. The cost of imaging was taken from our institution's global charge list. Imaging was deemed unnecessary if it was not recommended by our radiologists after review of the initial imaging study. The difference in cost was calculated by subtracting the cost of imaging recommended by each radiologist from the cost of unnecessary imaging. The sensitivity and specificity for distinguishing enchondromas from chondrosarcomas was calculated. A minimum of 2 years from diagnosis of an enchondroma was required to monitor for malignant transformation.
RESULTS - Of patients diagnosed with an enchondroma, 85 % presented with AIS. The average enchondroma patient presented with one unnecessary AIS. The radiologists' interpretations agreed 85 % of the time for enchondromas and 100 % for chondrosarcomas. The sensitivity and specificity for distinguishing enchondromas from chondrosarcomas was 95 % for one radiologist and 87 and 95 % for the other. The average unnecessary cost per enchondroma patient was $1,346.18.
CONCLUSIONS - Unnecessary AIS are frequently performed and are a significant source of expense. The imaging algorithms outlined in this study may reduce unnecessary AIS.
BACKGROUND - Flexible intramedullary nailing (IMN) has become a popular technique for the management of unstable or open forearm fractures. Recent publications have suggested an increased incidence of delayed union and poor outcomes in older children and adolescents. The objective of this study was to review forearm fractures treated with IMN, comparing the rate of complications and outcomes between the 2 age groups. Our hypothesis was that IMN is an effective technique with a similar rate of complications in both age groups.
METHODS - An Institutional Review Board-approved retrospective review was conducted of pediatric forearm fractures treated from 1998 to 2008 at a single institution. Over the study time period, 4161 pediatric forearm fractures were managed nonoperatively (92%) and 353 were treated operatively with plate, cross-pin, or intramedullary fixation (8%). Patients with inadequate follow-up, cross-pin, or plate fixation were excluded. Medical records were reviewed for indications and complications. Complications were graded with a modification of the Clavien-Dindo classification. Outcomes were judged by a new grading system.
RESULTS - A total of 205 forearm fractures treated with IMN in 203 patients were identified. The mean age was 9.7 years (range, 1.7 to 16.2 y) and mean follow-up was 42 weeks. Operative indications were failure of closed treatment in 165 (80%) and open fracture in 40 (20%). Mean time from injury to IMN was 5.9 days (range, 0 to 25 d). Single bone IMN was performed in 40 of 185 both bone fractures (26%); there were 20 single-bone forearm fractures treated with IMN. Open reduction was required in 61/165 (37%) of closed fractures. Asymptomatic delayed union (grade 1 complication) was observed in 9 fractures (4%). More severe complications were noted in 17% (grade 2 to 4 complications). Postoperative compartment syndrome occurred in 3 isolated forearm fractures with a significant younger mean age (6.0 vs. 10 y, P=0.031). Overall, complications were significantly more frequent in children older than 10 years of age (25/101) as compared with younger children (13/104, P=0.031). In particular, delayed union was more common in children over the age of 10 years (9/101 vs. 1/104, OR=9.99, P=0.009). Outcomes were good or excellent in 91% of fractures. There was no statistical association of patient age with a fair or poor outcome.
CONCLUSIONS - IMN is an effective technique for pediatric forearm fractures with good to excellent outcomes in 91%. Complications are not infrequent with this technique, with complications of grade 2 to 4 severity in 17%. There was a 2-fold increase in the rate of complications in children over the age of 10 years. Compartment syndrome was more common in younger children. Patients and families should be counseled about the risks preoperatively.
PURPOSE - To assess the ability of volar locked plating to achieve and maintain normal radiographic parameters for articular stepoff, volar tilt, radial inclination, ulnar variance, and radial height in distal radius fractures.
METHODS - We performed a retrospective review of 185 distal radius fractures that underwent volar locked plating with a single plate design over a 5-year period. We reviewed radiographs and recorded measurements for volar tilt, radial inclination, ulnar variance, radial height, and articular stepoff. We used logistic regression to determine the association between return to radiographic standard norms and fracture type.
RESULTS - At the first and final postoperative follow-up visits, we observed articular congruence less than 2 mm in 92% of fractures at both times. Normal volar tilt (11°) was restored in 46% at the first follow-up and 48% at the final one. Radial inclination (22°) was achieved in 44% at the first follow-up and 43% at the final one, and ulnar variance (01 ± 2 mm) was achieved in 53% at the first follow-up and 53% at the final one. In addition, radial height (14 ± 1mm) was restored in 14% at the first follow-up and 12% at the final one. More complex, intra-articular fractures (AO class B and C and Frykman types 3, 4, 7, and 8) were less likely to be restored to normal radiographic parameters. However, because of the small sample size for some fracture types, it was difficult to discover significant associations between fracture type and radiographic outcome.
CONCLUSIONS - Volar locked plating for distal radius fractures achieved articular stepoff less than 2 mm in most fractures but only restored and maintained normal radiographic measurements for volar tilt, radial inclination, and ulnar variance in 50% of fractures. The ability of volar locked plating to restore and maintain ulnar variance and volar tilt decreased with more complex intra-articular fracture types.
TYPE OF STUDY/LEVEL OF EVIDENCE - Therapeutic IV.
Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.
A model was established in 39 dogs to investigate the growth factor modulation of regenerate bone in distraction osteogenesis. A segment of the diaphysis of the radius was resected unilaterally. An osteotomy was made proximal to the segmental defect to create a transport segment. A monolateral external fixator was applied. After a latency period, the segment was transported across the defect. One week after the transport assembly contacted the distal pin clamp, an ipsilateral osteotomy of the proximal ulna was performed. In 20 dogs, transforming growth factor-beta was injected into the regenerate bone halfway through the transport period. Four dogs were sacrificed before docking, when the regenerate bone was still immature. In specimens harvested halfway through the transport period, evidence was found of intramembranous ossification during distraction. In specimens harvested after the transport assembly contacted the distal pin clamp, evidence was found that the mature regenerate formed by endochondral ossification. Therefore, a combined mechanism of ossification is proposed for this segmental defect model that includes mechanical stimulus for bone differentiation. The one-time administration of transforming growth factor-beta retarded the formation of a stable, united regenerate. It is concluded that transforming growth factor-beta caused an effect opposite to that which was desired.
The performance of a bone biopsy results in a dramatically altered magnetic resonance image (MRI) signal in both the biopsied segment and the surrounding bone. An experimental canine model was used to determine the cause and imaging sensitivity of this postbiopsy signal change in the adjacent intraosseous contents. Six dogs were used in the study. Half of the dogs had the cortical window left open, and the other half had a polymethylmethacrylate plug inserted. After hemostatic closure, images were obtained immediately postbiopsy and 6 weeks thereafter. MRI defect length was examined on both T1 and T2 weighted sequences at both time periods. After the final image was taken at 6 weeks, the bone was harvested and examined grossly and histologically for the purpose of making pathoradiographic correlations. The results suggest that magnetic resonance imaging is a sensitive method that accurately reflects the defect caused by bone biopsy and the surrounding hemorrhage. The defect length increased in size over time. The image was slightly smaller than the corresponding histologic response. Insertion of a cortical plug had no predictable effect on defect length, which depended upon the amount of pressurization used during insertion. We conclude that MRI may be useful in the staging of intraosseous primary neoplasms of bone after bone biopsy, especially in the detection of an iatrogenically induced tumor/hemorrhage margin. This may be critical when planning an intraosseous surgical resection in which short, wide margins are anticipated.