High-speed fluoroscopic imaging for investigation of three-dimensional knee kinematics before and after marathon running

BackgroundKnee injuries often occur during or shortly after marathon running, and are linked to altered knee kinematics.Research questionThe kinematics of healthy knees during pre- and post-marathon running have not been examined with high-speed fluoroscopy. This study aimed to evaluate the effects of marathon running on knee kinematics during walking and running by using a combined high-speed fluoroscopy and MRI technique.MethodsTen healthy runners underwent knee MRI within 24 h before marathon running to construct three-dimensional (3D) knee models. Knee kinematics during treadmill walking and running were evaluated using high-speed fluoroscopy (200hz) within 24 h before and as soon as possible (within 5 h) after marathon running. All pre- and post-marathon measurements were compared.Results(1) For post-marathon walking, posterior femoral translation increased 1.4 mm at initial contact (p = 0.015); proximal-distal distance of tibia and femur decreased 0.7 mm and 0.8 mm at initial contact and after contact, respectively (p = 0.039, p = 0.046); and valgus femur rotation increased 1.2° after contact (p = 0.027). (2) For post-marathon running, proximal-distal distance decreased 0.7 mm and 1.0 mm at initial contact and after contact (p = 0.011, p = 0.003) respectively; knee flexion decreased 4.3° before contact (p = 0.007); knee flexion increased 1.8° and 2.6° at initial contact and after contact, respectively (p = 0.038, p = 0.011); external femoral rotation increased 1.2° and 1.8° at initial contact and after contact, respectively (p = 0.012, p = 0.037). Valgus femoral rotation after contact increased 2.3° (p = 0.001).SignificancePost-marathon changes in valgus and external femoral rotation, knee flexion, posterior femoral translation, and proximal-distal distance may increase the risk of knee injury. This study provides information to better understand the response of the knee to marathon running.     

Comparable efficacy of 100 mg aspirin twice daily and rivaroxaban for venous thromboembolism prophylaxis following primary total hip arthroplasty: a randomized controlled trial

Background:Aspirin has demonstrated safety and efficacy for venous thromboembolism (VTE) prophylaxis following total hip arthroplasty (THA); however, inconsistent dose regimens have been reported in the literature. This study aimed to evaluate and compare the safety and efficacy of 100 mg aspirin twice daily with rivaroxaban in VTE prophylaxis following THA.Methods:Patients undergoing elective unilateral primary THA between January 2019 and January 2020 were prospectively enrolled in the study and randomly allocated to receive 5 weeks of VTE prophylaxis with either oral enteric-coated aspirin (100 mg twice daily) or rivaroxaban (10 mg once daily). Medication safety and efficacy were comprehensively evaluated through symptomatic VTE incidence, deep vein thrombosis (DVT) on Doppler ultrasonography, total blood loss (TBL), laboratory bloodwork, Harris hip score (HHS), post-operative recovery, and the incidence of other complications.Results:We included 70 patients in this study; 34 and 36 were allocated to receive aspirin and rivaroxaban prophylaxis, respectively. No cases of symptomatic VTE occurred in this study. The DVT rate on Doppler ultrasonography in the aspirin group was not significantly different from that in the rivaroxaban group (8.8% vs. 8.3%, χ² = 0.01, P = 0.91), confirming the non-inferiority of aspirin for DVT prophylaxis (χ² = 2.29, P = 0.01). The calculated TBL in the aspirin group (944.9 mL [658.5–1137.8 mL]) was similar to that in the rivaroxaban group (978.3 mL [747.4–1740.6mL]) (χ² = 1.55, P = 0.12). However, there were no significant inter-group differences in HHS at post-operative day (POD) 30 (Aspirin: 81.0 [78.8–83.0], Rivaroxaban: 81.0 [79.3–83.0], χ² = 0.43, P = 0.67) and POD 90 (Aspirin: 90.0 [89.0–92.0], Rivaroxaban: 91.5 [88.3–92.8], χ² = 0.77, P = 0.44), the incidence of bleeding events (2.9% vs. 8.3%, χ² = 0.96, P = 0.33), or gastrointestinal complications (2.9% vs. 5.6%, χ² = 1.13, P = 0.29).Conclusion:In terms of safety and efficacy, the prophylactic use of 100 mg aspirin twice daily was not statistically different from that of rivaroxaban in preventing VTE and reducing the risk of blood loss following elective primary THA. This supports the use of aspirin chemoprophylaxis following THA as a less expensive and more widely available option for future THAs.Trial Registration:Chictr.org, ChiCTR18000202894; http://www.chictr.org.cn/showproj.aspx?proj=33284     

Morphological measurements of the posterior surface of the normal proximal tibia in a healthy Chinese population

BackgroundTo measure and calculate the morphological parameters and determine the anatomical characteristics of the posterior surface of the proximal tibia in a healthy Chinese population.MethodsA total of 150 volunteers with normal knees were enrolled. The parameters in the multi-slice spiral computed tomography (MSCT) three-dimensional (3-D) reconstruction images were measured and calculated by two independent qualified observers. The differences and correlation were investigated. The intraclass correlation coefficient (ICC) was used to assess inter-observer reliability.ResultsThe posterior margin of the tibial plateau is presented as two superior arc-shapes. The central angles of these arcs were 118° ± 14° (medial) and 106° ± 20° (lateral). The radii of these arcs both showed a skewed distribution. The median radii of the arcs were 22 mm in the medial and 20 mm in the lateral. There were two significant angles present in the sagittal plane of the posterior cortex of the proximal tibia. The first angles were 39° ± 7° (medial) and 47° ± 7° (lateral). The second angles were 39° ± 4° (medial) and 41° ± 5° (lateral). Significant differences were observed in the central angles and the first angles but not in the second angles between the medial and lateral. There were no significant differences between different gender groups, and between left and right limbs. All of these parameters exhibited excellent to moderate ICC.ConclusionDue to the varying anatomic morphology between the postero-medial and postero-lateral surface of the proximal tibia, the internal fixation implants of these two parts should be designed differently.     

颈椎椎板成形术后脊髓后移的相关因素分析

 目的 探讨颈后路单开门椎板成形术后脊髓后移的影响因素及其规律。方法 2008年2月至2010年10月收治的压迫性颈脊髓病患者经筛选后43例纳入本研究,均接受C₃～C₇后路单开门椎板成形术,男32例,女11例;年龄33～78岁,平均57.9岁。脊髓型颈椎病伴发育性颈椎管狭窄30例,颈椎后纵韧带骨化症13例。门轴侧关节突螺钉锚定法21例,保留门轴侧肌肉韧带复合体的钛缆悬吊法22例。术前、术后3个月颈椎中立位MRI正中矢状面测量各节段代表脊髓及硬膜囊后移的参数：脊髓前缘后移,脊髓后缘后移,硬膜囊前缘后移,硬膜囊后缘后移;将齿突与T₁椎体后下角的连线定义为E线,其长度为E值,从每个基准点向E线作垂线,每个垂线段的长度为Px(x=1~6),得到代表每个节段局部曲度的参数(100×Px/E);以颈椎曲度指数 (curvature index, CI) 表示颈椎整体曲度。对以上参数进行线性相关分析。结果 硬膜囊前缘后移在不同水平无明显变化,脊髓前缘后移、脊髓后缘后移与硬膜囊后缘后移则随所处节段不同而相应发生变化,且三者的变化具有一致性。脊髓后缘后移最大值位于C_5,6水平,但C_5,6水平脊髓后缘后移与CI无相关性。相关分析表明脊髓后缘后移与硬膜囊后缘后移呈高度线性相关,与(100×Px/D)具有较低的相关性 。结论 颈椎单开门椎管扩大成形术后脊髓的后移程度与同水平硬膜囊的后移程度高度相关,与局部曲度相关性较弱,与颈椎整体曲度无相关性。     

阿仑膦酸钠抑制骨巨细胞瘤细胞生长和诱导其凋亡的研究

[目的]骨巨细胞瘤是一种潜在的恶性病变，具有手术后易复发的特点。二膦酸盐是抗骨质疏松药，可以抑制破骨细胞性骨吸收，近来发现其还有抗肿瘤作用。本研究是探讨第3代二膦酸盐——阿仑膦酸钠是否能够抑制骨巨细胞瘤细胞生长，诱导骨巨细胞瘤细胞凋亡，探讨应用二膦酸盐能否成为一个防止骨巨细胞瘤复发的方法。[方法]在体外培养骨巨细胞瘤细胞，给予不同浓度的阿仑膦酸钠，作用不同时间后，应用M1Tr法检测骨巨细胞瘤细胞的活性是否受到抑制，TUNEL染色法观察骨巨细胞瘤细胞经药物作用后是否发生凋亡，流式细胞术检测凋亡率，观察药物作用后凋亡蛋白Caspase-3活性的表达是否增加。[结果]经阿仑膦酸钠作用后瘤细胞活性减低，可以发现阿仑膦酸钠抑制骨巨细胞瘤细胞生长的作用可以随时间和浓度的增加而增高。TUNEL法观察到瘤细胞凋亡染色阳性，流式细胞仪检测阿仑膦酸钠作用后骨巨细胞瘤细胞的凋亡率也随着时间和浓度的增加而增高。进一步检测随着阿仑膦酸钠浓度的提高，骨巨细胞瘤细胞的Caspase-3活性表达也增加。[结论]阿仑膦酸钠对于体外培养的骨巨细胞瘤细胞的活性有抑制作用，可以抑制其生长并诱导肿瘤细胞内的Caspase-3活性表达，促其凋亡，阿仑膦酸钠可能成为治疗和预防骨巨细胞瘤复发的一个治疗方法，但还需要进一步的体内实验研究。     

脊柱小关节骨关节炎诊治专家共识

骨关节炎的流行病学、基础和临床研究更多集中在四肢关节,脊柱疾病方面往往更关注的是椎间盘退变及相关神经损伤。临床工作中许多医生对脊柱小关节骨关节炎缺乏足够的认识和关注,从而导致部分脊柱小关节骨关节炎患者被误诊误治。通过查阅文献,遵循循证医学原则,经过全国专家组反复讨论,我们对脊柱小关节骨关节炎诊断和治疗问题达成共识,供广大医师在临床工作中参考应用。脊柱小关节骨关节炎的诊断需结合患者的病史、症状、体征和影像学检查,必要时进行选择性阻滞术,还需要和多种脊柱疾患相鉴别。治疗手段包括基础治疗、药物治疗、介入治疗和手术治疗。在临床工作中,广大医生需对脊柱小关节骨关节炎加强重视、进行正确诊断和有效治疗。     

ASA grade and Charlson Comorbidity Index of spinal surgery patients: correlation with complications and societal costs

Background contextThe Charlson Comorbidity Index (CCI) and the American Society of Anesthesiologists (ASA) Physical Status Classification System (ASA grade) are useful for predicting morbidity and mortality for a variety of disease processes.PurposeTo evaluate CCI and ASA grade as predictors of complications after spinal surgery and examine the correlation between these comorbidity indices and the cost of care.Study design/settingProspective observational study.Patient sampleAll patients undergoing any spine surgery at a single academic tertiary center over a 6-month period.Outcome measuresDirect health-care costs estimated from diagnosis related group and Current Procedural Terminology (CPT) codes.MethodsDemographic data, including all patient comorbidities, procedural data, and all complications, occurring within 30 days of the index procedure were prospectively recorded. Charlson Comorbidity Index was calculated from International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes and ASA grades determined from the operative record. Diagnosis related group and CPT codes were captured for each patient. Direct costs were estimated from a societal perspective using Medicare rates of reimbursement. A multivariable analysis was performed to assess the association of the CCI and ASA grade to the rate of complication and direct health-care costs.ResultsTwo hundred twenty-six cases were analyzed. The average CCI score for the patient cohort was 0.92, and the average ASA grade was 2.65. The CCI and ASA grade were significantly correlated, with Spearman ρ of 0.458 (p<.001). Both CCI and ASA grade were associated with increasing body mass index (p<.01) and increasing patient age (p<.0001). Increasing CCI was associated with an increasing likelihood of occurrence of any complication (p=.0093) and of minor complications (p=.0032). Increasing ASA grade was significantly associated with an increasing likelihood of occurrence of a major complication (p=.0035). Increasing ASA grade showed a significant association with increasing direct costs (p=.0062).ConclusionsAmerican Society of Anesthesiologists and CCI scores are useful comorbidity indices for the spine patient population, although neither was completely predictive of complication occurrence. A spine-specific comorbidity index, based on ICD-9-CM coding that could be easily captured from patient records, and which is predictive of patient likelihood of complications and mortality, would be beneficial in patient counseling and choice of operative intervention.     

Delayed peroneal nerve palsy after total knee arthroplasty—A rare complication of tibial osteolysis

We present a case of peroneal nerve palsy which occurred 12 years after primary total knee arthroplasty as a result of extensive tibial osteolysis. The tibial osteolytic cyst extended through a cortical defect in the proximal tibia into the anterolateral compartment of the leg causing compressive neuropathy of the peroneal nerve. Imaging included radiographs, CT scan and MRI. At revision surgery, the tibial component was found loose with significant proximal tibial osteolysis. The cyst in the leg was decompressed through the cortical defect in the proximal tibia and analysis of cystic fluid revealed polyethylene debris. At 7-year follow-up after revision, the osteolytic cyst had resolved but the peroneal palsy did not recover.     

Osteochondritis dissecans with a large osteochondral free body in the posterolateral compartment of the knee: A case report

A large osteochondral fragment trapped in the posterolateral compartment of a knee was removed from a posteromedial portal through the trans-septal portal and fixed on an osteochondral defect of the lateral femoral condyle in a 16 year-old boy. When a free body in the posterolateral compartment is so large that enlargement of the portal site is required for removal, doing so from a posteromedial portal is safer and easier than from a posterolateral portal.