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1.
《Journal of cranio-maxillo-facial surgery》2022,50(8):651-656
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
2.
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
3.
《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
4.
目的探讨关节镜清理术联合透明质酸钠治疗膝骨性关节炎患者的效果。方法100例膝骨性关节炎患者随机分为两组各50例,对照组采用关节镜清理术治疗,实验组采用关节镜清理术联合透明质酸钠治疗,比较两组的关节液炎性因子水平、膝关节功能以及疼痛情况。结果治疗后,实验组的TNF-α、IL-6、IL-8水平均显著低于对照组(P<0.05)。治疗1个月、3个月、6个月后,实验组的Lysholm评分均显著高于对照组,VAS评分均显著低于对照组(P<0.05)。结论关节镜清理术联合透明质酸钠治疗膝骨性关节炎可降低患者关节液炎性因子水平,改善膝关节功能,减轻疼痛。 相似文献
5.
C. Vogrig J.-S. Louis F. Avila R. Gillet G. Hossu A. Blum-Moyse P.A. Gondim Teixeira 《Diagnostic and interventional imaging》2021,102(3):181-187
PurposeThe purpose of this study was to compare morphologic assessment and relaxometry of patellar hyaline cartilage between conventional sequences (fast spin-echo [FSE] T2-weighted fat-saturated and T2-mapping) and synthetic T2 short-TI inversion recovery (STIR) and T2 maps at 1.5 T magnetic resonance imaging (MRI).MethodThe MRI examinations of the knee obtained at 1.5 T in 49 consecutive patients were retrospectively studied. There were 21 men and 28 women with a mean age of 45 ± 17.7 (SD) years (range: 18–88 years). Conventional and synthetic acquisitions were performed, including T2-weighted fat-saturated and T2-mapping sequences. Two radiologists independently compared patellar cartilage T2-relaxation time on conventional T2-mapping and synthetic T2-mapping images. A third radiologist evaluated the patellar cartilage morphology on conventional and synthetic T2-weighted images. The presence of artifacts was also assessed. Interobserver agreement for quantitative variables was assessed using intraclass correlation coefficient (ICC).ResultsIn vitro, conventional and synthetic T2 maps yielded similar mean T2 values 58.5 ± 2.3 (SD) ms and 58.8 ± 2.6 (SD) ms, respectively (P = 0.414) and 6% lower than the expected experimental values (P = 0.038). Synthetic images allowed for a 15% reduction in examination time compared to conventional images. On conventional sequences, patellar chondropathy was identified in 35 patients (35/49; 71%) with a mean chondropathy grade of 4.8 ± 4.8 (SD). On synthetic images, 28 patients (28/49; 57%) were diagnosed with patellar chondropathy, with a significant 14% difference (P = 0.009) and lower chondropathy scores (3.7 ± 4.9 [SD]) compared to conventional images. Motion artifacts were more frequently observed on synthetic images (18%) than on conventional ones (6%). The interobserver agreement was excellent for both conventional and synthetic T2 maps (ICC > 0.83). Mean cartilage T2 values were significantly greater on synthetic images (36.2 ± 3.8 [SD] ms; range: 29-46 ms) relative to conventional T2 maps (31.8 ± 4.1 [SD] ms; range: 26-49 ms) (P < 0.0001).ConclusionDespite a decrease in examination duration, synthetic images convey lower diagnostic performance for chondropathy, greater prevalence of motion artifacts, and an overestimation of T2 values compared to conventional MRI sequences. 相似文献
6.
IntroductionRealignment knee osteotomy relies on accurate preoperative assessment of coronal alignment. Weightbearing (WB) ‘long-leg’ (LL) radiographs are the accepted gold-standard investigation, though in practice standard knee radiographs (short leg; SL) and non-weightbearing (NWB) cross-sectional imaging such as computed tomography (CT) scanograms have been used. We compare the accuracy of SL and NWB radiographs to formal LL alignment radiographs.MethodsA prospectively maintained osteotomy database was reviewed to identify the study population. All patients underwent standardised weightbearing long-leg alignment radiographs. The series was screened consecutively until 30 patients who also underwent WB SL radiographs (‘WB cohort’), and 30 with NWB SL (‘NWB cohort’) radiographs, were identified. Anatomic tibiofemoral angle was calculated by independent reviewers using a validated technique from both radiographs and contrasted.Results60 patients were identified as outlined in the study protocol. There were no differences in baseline demographics. Coronal alignment calculated from SL and LL radiographs differed significantly (median difference 2.1°, p < 0.001). Alignment values from weightbearing SL radiographs demonstrated markedly greater agreement with LL values than those from NWB radiographs (intraclass correlation coefficient 0.878 vs 0.657), with the NWB cohort also exhibiting greater outlier and extreme outlier incidence.ConclusionOur data adds to the growing evidence that SL radiographs are inadequate in the interpretation of knee alignment. In addition, we demonstrate that NWB radiographs (and by extension other NWB modalities such CT scanograms) demonstrate poorer agreement to gold-standard than WB methods. Coronal alignment of the knee cannot be reliably measured from non-weightbearing imaging modalities.Implications for practiceThough potentially useful as an adjunct, non-weightbearing cross-sectional imaging and standard knee radiographs should not be used as a proxy for formal weightbearing long-leg radiographs in osteotomy planning. 相似文献
7.
8.
膝骨关节炎(Knee Osteoarthritis, KOA)属于临床难治性疾病,其高发病率、高致残性给国民健康、社会发展造成了沉重的负担。在这种不利局面下,中医药在KOA的临床防治上发挥了巨大的作用,其根据“辨证施治”理念的指导对患者采用个体化治疗往往能够取得良好的临床疗效 。然而中医学在传统认知上作为经验医学的集成,现有的KOA中医药基础研究结果尚未完全阐明其客观化、现代化的属性,阻碍了中医药防治KOA科学内涵的揭示以及全面、系统的临床研究的开展和新药研发,如何开展完善、合理、可行的基础研究以进行KOA中医药客观化和现代化探索成为研究者不得不解决的重大难题。随着系统生物学知识结构和研究手段的完善与更新,其与中医药的结合已经成为阐释并创新中医药理论内核、突破中医药研究瓶颈的重要方法。本文通过总结、分析目前KOA中医药基础研究的现状与不足,突出系统生物学在目前KOA中医药研究中的关键作用及应用趋势,以期为今后KOA的中医药研究和发展提供新的思路与对策。 相似文献
9.
《Gait & posture》2022
BackgroundTraditional running shoes with heel-to-toe drops is thought to be a contributor to increased patellofemoral joint stress, which is proposed as a mechanism of patellofemoral pain.Research questionIs there an increase in patellofemoral joint stress when running in shoes with drops compared to running in shoes without a drop?MethodsLower limbs kinematics and ground reaction force were collected from eighteen healthy runners during over-ground running in shoes with 15 mm, 10 mm, 5 mm drops, and without a drop. Patellofemoral joint force and stress were calculated from the kinematic and kinetic data using a biomechanical model of the patellofemoral joint.ResultsThe peak patellofemoral joint stress was increased by more than 15% when running in shoes with 15 mm and 10 mm drops compared to running in shoes without a drop (p = 0.003, p = 0.001). The knee flexion angle was significantly increased when running in shoes with 15 mm, 10 mm and 5 mm drops (p = 0.014, p = 0.003, p = 0.002), the knee extension moment (p = 0.009, p = 0.002) and patellofemoral joint force (p = 0.003, p = 0.001) were increased when running in shoes with 15 mm and 10 mm drops, compared to running in shoes without a drop.SignificanceCompared to running in shoes without a drop, running in shoes with drops > 5 mm increase the peak patellofemoral joint stress significantly, which is mainly due to the increased knee extension moment. 相似文献
10.