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Background context
It has been reported that newly developed osteoporotic vertebral compression fractures (OVCFs) occur at a relatively high frequency after treatment. While there are many reports on possible risk factors, these have not yet been clearly established.Purpose
The purpose of this study was to investigate the risk factors for newly developed OVCFs after treatment by vertebroplasty (VP), kyphoplasty (KP), or conservative treatment.Study design/setting
A retrospective comparative study.Patient sample
One hundred thirty-two patients who had radiographic follow-up data for one year or longer among 356 patients who were diagnosed with OVCF and underwent VP, KP or conservative treatment between March 2007 and February 2016.Outcome measures
All records were examined for age, sex, body mass index (BMI), rheumatoid arthritis and other medical comorbidities, osteoporosis medication, bone mineral density (BMD), history of vertebral and nonvertebral fractures, treatment methods used, level of fractures, and presence of multiple fracture sites.Methods
Patients were divided into those who manifested new OVCF (Group A) and those who did not (Group B). For the risk factor analysis, student's t-tests and chi-square tests were used in univariate analysis. Multivariate logistic regression analysis was carried out on variables with a p<.1 in the univariate analysis.Results
Newly developed OVCFs occurred in 46 of the 132 patients (34.8%). Newly developed OVCF increased significantly with factors such as average age (p=.047), low BMD T-score of the lumbar spine (p=.04) and of the femoral neck (p=.046), advanced age (>70 years) (p=.011), treatment by cement augmentation (p=.047) and low compliance with osteoporosis medication (p=.029). In multivariate regression analysis, BMD T-score of the lumbar spine (p=.009) and treatment by cement augmentation (p=.044) showed significant correlations with the occurrence of new OVCFs with a predictability of 71.4%.Conclusion
Osteoporotic vertebral compression fracture patients with low BMD T-score of the lumbar spine and those who have been treated by cement augmentation have an increased risk of new OVCFs after treatment and, therefore, require especially careful observation and attention. 相似文献Objective
Symptomatic distal interlocking screws in retrograde femoral nailing are common due the difficulties of imaging the trapezoidal femur. Screws appearing to have appropriate length on imaging may possibly be prominent, creating symptoms. Screw trajectory may influence the degree of this radiographic error. We hypothesize that external rotation of screw trajectory will increase measurement error of screw length.Design
Retrospective.Setting
Urban Level I Tertiary Trauma Center.Participants
283 patients with Computer Tomography (CT) scans of the native knee were retrospectively identified. Simulation was done of the trajectory of an interlock at 20?mm and 40?mm proximal to the nail entry point, which represent common screw positions associated/not associated respectively, with removal. The distance between the radiographic medial cortex and the tip of the transverse screw was calculated (D). The angle (Ψ) between the transverse trajectory and a modified trajectory aimed at the most medial cortex to avoid radiographic measurement error was calculated. Geometric modeling was utilized to calculate the measurement error (D) in the event of accidental external rotation. The angle of the medial slope was also measured (Θ).Intervention
Review of CT imaging of normal distal femora.Main Outcome Measurements
CT measurements of distal femora.Results
The mean distance (D) at 20/40?mm was 4.21 [95%CI 4.02–4.402] and 2.03?mm [95%CI 1.78–2.83], respectively (p?<?0.0001). The mean angle (Ψ) between the transverse and modified trajectory at 20/40?mm was 12° [95%CI 11.5–12.5] and 9.60° [95%CI 9–10.2], respectively (p?<?0.0001). External rotation by a similar amount nearly triples the measured difference (D). The measured medial slope was significantly increased as screws were placed more proximal (Θ20 mm 46.5 vs Θ40 mm: 48.7?°, p?<?0.00001).Conclusion
The distance between the perceived medial cortex and the tip of the most transverse screw is 4.21?mm and could account for painfully prominent screws. In more proximal screws this distance is decreased. Internal rotation of the screw trajectory 12° can reduce this distance (D), which has implications in nail design. External rotation, amplifies this difference nearly three-fold. Surgeons should avoid external rotation of the aiming arm to prevent prominent screws. 相似文献Materials and Methods: Relevant papers in PubMed published through June 2017 were selected to track updated information about PTL with an emphasis on diagnosis and novel therapeutic management.
Results: The most frequent cases include non-Hodgkin lymphoma derived from B-cells, mainly diffuse large B-cell lymphoma (DLBCL) followed by mucosa-associated lymphoid tissue (MALT) lymphoma or a mixed type. Other subtypes are less common. Lymphomas derived from T-cells and Hodgkin lymphomas are extremely rare. Hashimoto's autoimmune thyroiditis has been implicated as a risk factor for lymphoma. At the molecular level, the Wnt5a protein and its receptor Ror2 are involved in the course of the disease. Ultrasonography, fine needle aspiration (FNA) biopsy, and core or open biopsy combined with new diagnostic facilities contribute to an accurate diagnosis. An increased potential exists for a cure without the need for a radical surgical procedure. Modern chemoradiation therapy plus the monoclonal antibody rituximab, which acts against CD20, have limited the need for surgical interventions and provide an excellent outcome in most cases. However, some cases have resulted in treatment failure or recurrence.
Conclusions: A multidisciplinary approach must be used to define the management policy in each case. Future efforts by researchers are likely to be focused on the molecular level. 相似文献