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BackgroundProximal tibia vara has drawn interest since the concept of constitutional varus was introduced. Proximal tibia vara is a condition where the knee varus tilt the tibia condyle medially and shift the tibial articular surface medially. This condition affects medial proximal tibial angle measurements and the placement of the tibial implant in knee replacement surgery. Thus, it challenged the neutral knee arthroplasty alignment target because some people may present a proximal tibia vara. This study assesses the prevalence of the proximal tibia vara and the correlation to knee osteoarthritis grade.MethodsThis retrospective study was carried out from January 2021 to June 2021. Eighty-five limbs were included with the following inclusion criteria: knee osteoarthritis patients who received a long view lower extremity radiograph. The exclusions criteria were (1) patients who had undergone arthroplasty and lower extremity surgery before and (2) valgus knee deformity. The outcomes in this study were HKAA, MAD, TAD, MPTA, PTRP, LDFA, and PTS. Intraclass correlation (ICC) using two-way mixed was used to assess the reproducibility of the radiographic parameters. Multiple logistic regression was used to evaluate the correlation between knee osteoarthritis grade and radiographs parameters (MAD and TAD).ResultA total 85 limbs from 52 patients were assessed in this study. Proximal tibia vara was found in 18 knees (21%.). The logistic regression was performed to assess the correlation between the severity of the knee osteoarthritis and radiographic parameters (MAD, TAD, LDFA, and PTS) with an overall p-value < 0.001 and pseudo-R2 = 0.29.ConclusionA significant portion of patients with knee osteoarthritis have proximal tibia vara, and it is a pre-existing condition. Since the pre-existing proximal tibia vara affects preoperative measurements, a long-standing lower extremity x-ray is recommended to be obtained as part of knee replacement preparation.  相似文献   
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《Radiography》2022,28(3):663-667
IntroductionAnti-scatter grids efficiently reduce scatter radiation from reaching the imaging receptor, enhancing image quality; however, the patient radiation dose increases in the process. There is disagreement regarding the thickness thresholds for which anti-scatter grids are beneficial. This study aims to establish a thickness threshold for the use of anti-scatter grids to optimise adult knee radiography.MethodsThe study consisted of two phases. In Phase 1 phantom knee radiographs were acquired at varying thicknesses (10–16 cm) and tube voltages (60–80 kV). For each thickness and tube voltage, images with and without an anti-scatter grid were obtained. In Phase 2, two radiologists and three radiographers, evaluated the image quality of these images. Visual Grading Analysis (VGA) scores were analysed using Visual Grading Characteristics (VGC) based on the visualisation of five anatomic criteria.ResultsThe average DAP decreased by 72.1% and mAs by 73.1% when removing the anti-scatter grid. The VGC revealed that overall images taken with an anti-scatter grid have better image quality (AUC ≥0.5 for all comparisons). However, the anti-scatter grids could be removed for thicknesses 10, 12 and 14 cm in conjunction with using 80 kVp,.ConclusionAnti-scatter grids can be removed when imaging adult knees between 10 and 12 cm using any kVp setting since the radiation dose is reduced without significantly affecting image quality. For thicknesses >12 cm, the use of anti-scatter grids significantly improves image quality; however, the radiation dose to the patient is increased. The exception is at 14 cm used with 80 kVp, where changes in image quality were insignificant.Implications for practiceOptimisation by removing anti-scatter grids in adult knee radiography seems beneficial below 12 cm thickness with any kVp value. Since the average knee thickness ranges between 10 and 13 cm, anti-scatter grid can be removed for most patients. Nevertheless, further studies are recommended to test if this phantom-based threshold applies to human subjects.  相似文献   
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This study aims to describe intraoperative complications in temporomandibular joint arthroscopy in patients with Wilkes stage II, III y IV. An analytic observational retrospective study. Inclusion criteria were patients who had no improvement with conservative treatment diagnosed as Wilkes II stage to Wilkes stage IV, and no previous TMJ surgery. Exclusion criteria were disc perforation observed by arthroscopy. Data collected from 458 patients (899 arthroscopies). Of this population, 772 (85.8%) arthroscopies correspond to women, and 127 men (14.1%). Of the sample evaluated, 368 (40.9%) were arthroscopic without discopexy, and 531 (59%) were arthroscopic with discopexy using resorbable pins. In total, 330 complications (36.7%) were found, of which 293 (32.5%) were implicated with iatrogenic damage to the anatomy, and 36 (4%) were associated with some instrument failure. Of this total number of complications, 191 (51.9%) of 386 corresponded to the arthroscopy without discopexy group and 138 (25.9%) of 531 corresponded to the arthroscopy with discopexy group. These study data suggest that the main complications were irrigation fluid extravasation (p = 0.000), and intra-articular bleeding (p = 0.001) followed by pin problems (p = 0.001) in cases of arthroscopies with discopexy. Within the limitations of the study it seems that the learning curve has an important influence on the occurrence of complications. At the beginning of the learning curve, complications are more related to anatomy. Afterwards, the rate of complications decreases but they are more related to the instruments used in advanced techniques. Therefore, proper training and a wide learning curve can reduce the risk of complications and if any occur, more timely management could be given.  相似文献   
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