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目的 探讨运动性膝关节损伤的MRI表现特点.方法 对30例体育运动后出现膝关节损伤症状的患者进行1.5T磁共振扫描,部分患者行膝关节镜检查,并对所得的MR图像与关节镜结果进行回顾性分析.结果 30例运动性膝关节损伤患者中,骨挫伤者18例,MRI表现为股骨髁、胫骨髁、髌骨于T2W1序列上见斑片样高信号影;半月板损伤者25例,其中Ⅰ-Ⅱ度损伤18例,Ⅲ度损伤7例;膝关节韧带损伤者20例;关节软骨面毛糙、变薄者5例;膝关节腔及周围滑膜囊内见积液征象者20例.结论 高场磁共振成像能准确地对运动性膝关节损伤做出诊断. 相似文献
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MICHAEL E. FELTNER DANIEL J. FRASCHETTI ROBERT J. CRISP 《Journal of sports sciences》2013,31(6):449-466
Twenty-five volleyball players (14 males, 11 females) were videotaped (60Hz) performing countermovement vertical jumps with and without an arm swing. Ground reaction force and video-based coordinate data were collected simultaneously. The resultant joint force and torque at the hip, knee, ankle and shoulder for two trials per subject per condition were computed and normalized. Average kinematic, resultant joint force and torque data were compared using repeated-measures analysis of variance. Larger values were recorded for the vertical velocity of the centre of mass at take-off in the jumps with (mean 2.75, s=0.3m.s-1) versus without (mean 2.44, s= 0.23m.s-1) an arm swing. The jumps with no arm swing produced larger torques at the hip during the first third of the propulsive phase (from zero to maximum vertical velocity of the centre of mass). During the final two-thirds of the propulsive phase, the arm swing augmented hip extensor torques by slowing the rate of trunk extension and placing the hip extensor muscles in slower concentric conditions that favoured the generation of larger forces and resultant joint torques. During the first two-thirds ofthe propulsive phase, knee extensor torque increased by 28% in the jumps with an arm swing, but maintained a relatively constant magnitude in the jumps with no arm swing. 相似文献
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目的：探讨3D打印技术对关节镜前交叉韧带重建手术的辅助价值。方法：对2017年12月-2018年5月收治的15例因运动损伤导致前交叉韧带断裂且需进行韧带重建的患者，术前进行膝关节CT扫描，Mimcs图像处理，通过3D打印膝关节模型，进行模型上股骨骨隧道定位，并进行预手术，测量隧道长度，术前及术后6个月进行膝关节Lysholm 评分以评估膝关节功能。结果：通过3D打印模型预手术，均较准确地定位了前交叉韧带股骨止点，预手术测量股骨骨隧道平均长度为（43.2±2.13） mm，术中测量（43.7±1.75） mm，术后再次CT测量骨隧道长度为（42.4±3.25） mm，差异无显著性意义（P>0.05），术前Lysholm评分（46.2±5.73） 分，术后Lysholm 评分（88.4±6.25） 分，差异有显著性意义（P＜0.05）。结论：3D打印模型预手术可以辅助关节镜术中较快速、准确地定位前交叉韧带股骨止点，模型与实体骨隧道契合度高，术后疗效优良。 相似文献
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Nili Steinberg Shay Tenenbaum Gordon Waddington Roger Adams Gal Zakin Aviva Zeev 《Journal of sports sciences》2020,38(7):719-730
ABSTRACTAiming to evaluate the prevalence of unilateral/bilateral patellofemoral pain (PFP) among young dancers, and to investigate whether different factors are associated with PFP in young dancers, 132 dancers aged 12–14 years were assessed for PFP. Anthropometric parameters, proprioception ability, dynamic postural balance (DPB), and muscle strength were measured. PFP was found in 64.1% of the dancers. No significant differences in the prevalence of dancers with no, unilateral, or bilateral PFP at different ages were found. Significant age effects were found for anthropometric and developmental measurements, and for intensity of training. PFP effect was found for DPB asymmetry, ankle proprioception, and leg-length %height. A higher hip abductor/adductor ratio was associated with PFP in 14-year-old dancers. Binomial logistic regression showed that increased number of hours per day (h/day) and decreased number of hours per week (h/week), low proprioception scores, greater leg length as %height, and more anterior DPB asymmetry were significant predictors of PFP. In conclusion: unilateral/bilateral PFP is common among young dancers. Body morphology, reduced ankle proprioception ability, DPB asymmetry, and increased h/day of practice are associated with PFP. Dance teachers should start monitoring the impact of training and implement injury modification/prevention strategies when their students are at a young age. 相似文献
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用模糊相关的运算方法 ,对单杠后倒挂膝上技术动作的运动生物力学因素进行分析 ,为优化单杠后倒挂膝上的技术教学提供了理论依据。 相似文献
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INTRODUCTION Steel framed structures are widely used in in-dustrial and commercial buildings. According to thedifferent lateral load resisting system, the steel framescan be mainly divided into four kinds (Fig.1a): themoment-resisting frame (MRF), concentricallybraced frame (CBF), eccentrically braced frame(EBF), and knee bracing frame (KBF). Fig.1b shows the difference in the lateral per-formances of the above frames that have similarstructural parameters. Although the MRF is an e… 相似文献
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本文就屈膝高摆在直道跨栏跑起跨技术中的作用及训练方法进行了分析与探讨,并提出了自己的见解,旨在提高教师、学生对该技术的重视,从而更好地完成教学任务,提高课堂教学质量。 相似文献
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Megan A. Bryanton Jason P. Carey Michael D. Kennedy 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(1):122-138
Hip extensor strategy, specifically relative contribution of gluteus maximus versus hamstrings, will influence quadriceps effort required during squat exercise, as hamstrings and quadriceps co-contract at the knee. This research examined the effects of hip extensor strategy on quadriceps relative muscular effort (RME) during barbell squat. Inverse dynamics-based torque-driven musculoskeletal models were developed to account for hamstrings co-contraction. Net joint moments were calculated using 3D motion analysis and force platform data. Hamstrings co-contraction was modelled under two assumptions: (1) equivalent gluteus maximus and hamstrings activation (Model 1) and (2) preferential gluteus maximus activation (Model 2). Quadriceps RME, the ratio of quadriceps moment to maximum knee extensor strength, was determined using inverse dynamics only, Model 1 and Model 2. Quadriceps RME was greater in both Models 1 and 2 than inverse dynamics only at barbell loads of 50–90% one repetition maximum. The highest quadriceps RMEs were 120 ± 36% and 87 ± 28% in Models 1 and 2, respectively, which suggests that barbell squats are only feasible using the Model 2 strategy prioritising gluteus maximus versus hamstrings activation. These results indicate that developing strength in both gluteus maximus and quadriceps is essential for lifting heavy loads in squat exercise. 相似文献
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Igor Setuain Nora Millor Miriam González-Izal Esteban M. Gorostiaga Marisol Gómez Jesús Alfaro-Adrián 《Sports biomechanics / International Society of Biomechanics in Sports》2013,12(3):323-339
Persistent biomechanical and jumping capacity alterations have been observed among female athletes who have sustained anterior cruciate ligament (ACL) injuries. The purpose of this study was to examine if biomechanical jumping differences persist among a cohort of elite female handball players with previous ACL reconstruction several years after return to top-level competition. In order to achieve this goal, a direct mechanics simplified analysis by using a single Inertial Sensor Unit (IU) was used. Twenty-one elite female (6 anterior cruciate ligament reconstructed and 15 uninjured control players) handball players were recruited and evaluated 6.0 ± 3.5 years after surgical anterior cruciate ligament reconstruction. Bilateral and unilateral vertical jumps were performed to evaluate the functional performance and a single inertial sensor unit was employed in order to collect 3D acceleration and 3D orientation data. Previously ACL-reconstructed analysed athletes demonstrated significant (p < 0.05) alterations in relation to the three-dimensional axis (X–Y–Z) supported accelerations and differing jump phase durations, including jumping performance values, in both bilateral and unilateral jumping manoeuvres several years after ACL reconstruction. Identification of the encountered deficits through the use of an IU devise could provide clinicians with a new reliable tool for movement analysis in a clinical setting. 相似文献
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