体育运动中骨损伤机制的理论分析

骨损伤是一种常见的运动损伤。无论骨损伤的原因及种类有多少,它都是由于力的作用而产生［１］。对骨损伤进行深入的组织学和力学分析对于损伤预防和治疗都有着深刻的意义。１　骨的结构分析１－１　骨的组织学结构骨是由骨膜、骨质和骨髓三部分构成,其中主要成分为骨质。通常所讲的骨折即指骨质的连续性受到伤害。骨质由骨密质和骨松质组成,骨密质主要分布于长骨骨干、扁骨和不规则骨的表面。骨密质看上去似很紧密,但其中仍含有许多相互连通的小管道,内有血管及神经,血管可供应骨组织营养和排出代谢产物。长骨骨干密质内的骨板排列很…     

运动与骨密度的研究进展

采用文献研究法研究了基础医学、临床医学、体育科学、运动医学和运动生物力学等有关专著和教材，研究结果表明，体育运动对不同生命时期的骨密度和骨量均有影响；不同运动方式和不同运动强度的运动对骨密度和骨代谢的影响不一样；过度训练可导致骨量、骨密度的降低和性激素的下降，可见，适宜的运动强度和运动方式，有利于改善骨代谢和提高骨密度。     

骨密度的测定方法及影响因素

介绍骨密度测量的常用方法,并系统划分影响骨密度的因素。判断骨密度与年龄的关系,为青少年的年龄推断提供依据,得出骨密度随着年龄的增长而出现与年龄相关的骨质量减少。根据测量青少年的骨密度来解释为什么男孩在青春期后期比女孩发育得快;特别对女性进行调查发现,体重与瘦组织和脂肪组织在男女各个部位的骨密度都有一定的相关性;体育锻炼对其骨质量峰值期和衰老下降期的影响及运动负荷与骨质量的关系,发现女性在绝经后期骨质量快速下降。老年退行性骨质量丢失和绝经后骨质量丢失的综合效应以及峰值骨质量低于男性的特点,使得老年妇女骨质疏松发生的危险性高于任何人,雌激素水平低下是长期的剧烈运动训练引起骨密度偏低的主要原因。     

太极柔力球运动对围绝经期女性雌激素及骨代谢指标的影响

目的探讨太极柔力球运动对围绝经期女性雌激素水平和骨代谢指标的影响。方法将自愿参加本实验的30名围绝经期女性随机分为太极柔力球组和对照组。指导太极柔力球组进行24周的锻炼,对照组不锻炼,保持原有生活状态。实验前后分别测定两组的睾酮(T)、雌二醇(E2)、促卵泡成熟激素(FSH)、促黄体生成激素(LH)、孕酮(P)及骨密度(BMD)、骨矿含量(BMC)、钙(Ca)、磷(P)、镁(Mg)和血碱性磷酸酶(ALP)。结果实验后太极柔力球组的E2、孕酮P及T明显升高,FSH和LH的值下降,尤其孕酮P的值与实验前相比差异极其显著(P<0.01)。全身各部位的骨密度无显著性变化,但脊柱、躯干部的骨矿含量明显提高。Ca、P和Mg与实验前相比有一定增长,统计学检验无显著性差异。结论 (1)太极柔力球运动可以促进卵泡雌激素和孕激素的分泌,改善围绝经期女性的雌激素水平;(2)太极柔力球运动可有效减轻围绝经期女性因增龄而引起的骨密度下降的趋势;(3)太极柔力球运动能提高血液镁、钙和磷的含量,对于维持围绝经期女性的骨矿含量,保持骨健康具有积极作用。     

青春期前期女子艺术体操运动员骨骼生长及代谢研究

目的:通过对参加艺术体操训练1年的青春期前期女子运动员进行骨密度、骨几何参数以及骨代谢相关生化标志物的检测分析,为艺术体操训练能有效促进青春期前期女子骨骼发展提供理论基础;方法:选取12名参加艺术体操训练1年的青春期前期女子运动员以及相同年龄段的未参加艺术体操训练的小学女生作为研究对象,通过双能X射线扫描仪对全身及局部区域的骨密度进行检测,并结合股骨强度分析软件获得两组研究对象的股骨颈的骨几何参数。此外,通过免疫学方法对两组研究对象的血样进行碱性磷酸酶、骨钙素和I型胶原C端肽含量测定;结果:参加艺术体操训练能使整体骨密度增加约10%,主要关节部位骨密度增加约为15%。在骨几何参数方面,截面面积、皮质骨厚度、剖面系数都有显著增加,但抗曲化率则存在一定程度上的下降。碱性磷酸酶浓度与对照组相比有显著上升,增加幅度高达32.7%,血清骨钙素与I型胶原C端肽与对照组相比增加约20%;结论:参加艺术体操锻炼对于青春期前期的女性能有效提高骨密度,对股骨颈的骨骼强度和抗骨折能力也有较大程度的提升。生化标志物分析结果表明,骨矿物质吸收能力和骨骼形成能力有显著增强。因此,长期艺术体操训练对青春期前期的女性有利于骨骼的健康发展。     

运动对骨密度的影响

运动是改善骨代谢、提高骨密度和预防骨质疏松的重要手段之一,但过度训练会导致骨量下降。本文通过对力量练习、冲击性练习等因素对骨密度影响的分析,以期为如何有效提高骨密度提供参考。     

人体骨密度研究进展

人体骨密度是反映骨代谢状况的重要指标,体育运动对骨密度有较大的影响。研究人体骨密度的变化情况可以了解骨代谢的状况,评价体育锻炼效果,进而指导大众健身。同时,骨密度也是评价运动员训练状况和身体机能状况的重要指标,运动训练中掌握骨密度的变化情况对于评价训练效果、防治运动性损伤具有重要的作用。目前双能X线吸收技术(DEXA)是测量骨密度的主要工具。研究表明,适宜的运动强度和运动方式,有利于改善骨代谢和提高骨密度。     

游泳运动对老年男性骨质代谢影响的研究

通过对长期参加游泳运动的老年人和不经常参加运动的老年人骨密度及骨代谢有关的生化指标的比较,探讨游泳运动对老年男性骨代谢的影响。结果显示,长期进行游泳运动的老年男性骨密度和血液中血钙、雌二醇、睾酮水平均显著高于对照组,同时,游泳Ⅰ组的骨密度显著高于游泳Ⅱ组。提示,长期游泳运动能够预防老年男性骨丢失和骨质疏松,且泳龄越长,效果越明显。     

纵跳对生长期大鼠骨密度、骨代谢生化指标的影响

目的:建立纵跳运动模型,探讨纵跳运动对大鼠骨代谢的影响;比较纵跳和游泳两种运动模式对骨代谢影响的差异,为青少年选择合理的运动方式提供参考.方法:将18只SD雄性大鼠随机分为安静组、游泳组和纵跳组.8周后,检测所有大鼠股骨和椎骨的骨量、骨密度、血乳酸及骨代谢生化指标.结果:纵跳组与安静组相比,股骨、椎骨骨密度明显高于后者,ALP有显著升高,TRACP有明显升高;游泳组与安静组相比,股骨骨密度没有差异,椎骨骨密度显著高于后者,ALP和TRACP都有明显升高.结论:本实验建立了SD大鼠纵跳运动模型,成功模拟了纵跳对大鼠骨代谢的主要生理刺激;大鼠血清骨代谢指标表现为纵跳比游泳能有效促进骨形成;运动能有效促进骨生长、明显提高股骨、椎骨骨密度;纵跳运动对生长期大鼠腰椎、股骨的发育有明显的促进作用.     

女运动员月经紊乱与骨损伤

运动对女运动员月经周期的影响作用尚有争议,本文概要介绍了国外学者关于运动诱发月经紊乱及发生机理的研究,并且阐述了运动员诱发雌激素水平下降会导致骨损伤(骨质疏松与骨折)。     

Gonadal hormones may predict structural bone fragility in elite female soccer player

ABSTRACT

Purpose: This study determined the impact of menstrual status on bone tissue in elite post-pubertal female soccer players over an entire season.

Methods: Fifty-one elite female soccer players participated. At baseline, forty-one were assigned to the low hormonal androgenic profile (low-HAPL) and 10 to the high hormonal androgenic profile (high-HAPL).

Results: An 8-month training program led to increased bone mineral density content (p<0.05). The low-HAPL athletes improved the Narrow neck average cortical thickness (ACT) by 1.4% and reduced the corresponding Buckling ratio (BR) by 2.6%, thus decreasing the fracture risk (p<0.05). The high-HAPL athletes decreased the Narrow neck ACT by 5.4% and increased the BR by 2.6%, increasing fracture risk (p<0.05). Differences were assigned as being “very likely beneficial” for the low-HAPL athletes, supported by very large (d=3.41) and large (d=1.58) effect sizes for the Narrow neck ACT and BR, respectively.

Conclusion: A season of soccer training has induced bone geometry improvements in adolescent females. Bone health parameters improved in the two clusters. However, high-HAPL athletes decreased its resistance to loading compare to low-HAPL athletes. Even if female players do not present clinical symptoms related to their hormonal status, sport medicine physicians should pay attention to their structural bone fragility.     

对应力性骨折的研究

应力性骨折发病初期往往不影响肢体的运动功能,因而易被忽视,误诊率较高。如果应力性骨折未能及时发现和治疗,随着病程的延长和损伤程度的加重,会出现骨皮质断裂而发展为完全骨折。通过文献资料法,对应力性骨折的生理机制、临床表现和诊断、应力性骨折的易发部位及防治进行了综述评价。     

Substitution of sedentary time with light physical activity is related to increased bone density in U.S. women over 50 years old. An iso-temporal substitution analysis based on the National health and Nutrition Examination Survey

Abstract

U.S. women are ageing. This is causing rises in osteoporosis prevalence and risk of fracture with related increases in health care costs. Replacing sedentary time with light physical activity may represent a cost effective public health solution to osteoporosis in elderly women. The National Health and Nutrition Examination Survey conducted over the period 2003–2006 provided cross-sectional data on bone mineral density and objectively assessed physical activity among 1,052 women aged 50–85 years old. Substitution analysis was applied to estimate increased bone mineral density and reduced osteoporosis for those women replacing 30?min of sedentary time with an equivalent amount of light physical activity. Substitution of 30?min of sedentary time with an equal amount of light physical activity was associated with increased bone mineral density of about 3?mg/cm2 and a 12% reduced risk of osteoporosis in the spine. When considering overweight women and women over 65 years of age, this association was reinforced and it extended to the pelvis, legs and trunk, resulting in a consistent bone mineral density increase of about 3–6?mg/cm2. The substitution of 30?min of sedentary time with an equal amount of light physical activity appears a possible primary prevention method to reduce osteoporosis and related increases in risk of fracture, mortality, and health care costs in women over 50 years old.     

Modifying landing mat material properties may decrease peak contact forces but increase forefoot forces in gymnastics landings

This study investigated how changes in the material properties of a landing mat could minimise ground reaction forces (GRF) and internal loading on a gymnast during landing. A multi-layer model of a gymnastics competition landing mat and a subject-specific seven-link wobbling mass model of a gymnast were developed to address this aim. Landing mat properties (stiffness and damping) were optimised using a Simplex algorithm to minimise GRF and internal loading. The optimisation of the landing mat parameters was characterised by minimal changes to the mat's stiffness (<0.5%) but increased damping (272%) compared to the competition landing mat. Changes to the landing mat resulted in reduced peak vertical and horizontal GRF and reduced bone bending moments in the shank and thigh compared to a matching simulation. Peak bone bending moments within the thigh and shank were reduced by 6% from 321.5 Nm to 302.5Nm and GRF by 12% from 8626 N to 7552 N when compared to a matching simulation. The reduction in these forces may help to reduce the risk of bone fracture injury associated with a single landing and reduce the risk of a chronic injury such as a stress fracture.     

Modifying landing mat material properties may decrease peak contact forces but increase forefoot forces in gymnastics landings

This study investigated how changes in the material properties of a landing mat could minimise ground reaction forces (GRF) and internal loading on a gymnast during landing. A multi-layer model of a gymnastics competition landing mat and a subject-specific seven-link wobbling mass model of a gymnast were developed to address this aim. Landing mat properties (stiffness and damping) were optimised using a Simplex algorithm to minimise GRF and internal loading. The optimisation of the landing mat parameters was characterised by minimal changes to the mat's stiffness ( < 0.5%) but increased damping (272%) compared to the competition landing mat. Changes to the landing mat resulted in reduced peak vertical and horizontal GRF and reduced bone bending moments in the shank and thigh compared to a matching simulation. Peak bone bending moments within the thigh and shank were reduced by 6% from 321.5 Nm to 302.5 Nm and GRF by 12% from 8626 N to 7552 N when compared to a matching simulation. The reduction in these forces may help to reduce the risk of bone fracture injury associated with a single landing and reduce the risk of a chronic injury such as a stress fracture.     

儿童青少年第二掌骨骨皮质发育的长期趋势

目的:通过研究近20年来儿童少年第二掌骨骨皮质发育状况,研究儿童少年生长发育期间的骨矿物质含量,进一步探讨骨皮质发育规律及长期变化情况,对全面揭示儿童少年的骨发育规律具有重要意义,为儿童少年生长发育研究提供理论依据.方法:以1985年和2005年骨发育调查样本为研究对象,用精确到0.02 rrffn的游标卡尺在第二掌骨中点部位,测量掌骨干横径和骨髓腔宽度,骨干横径减去骨髓腔宽度即求出两侧皮质厚度,按Barnett公式计算掌骨皮质指数.结论:1)1985-2005年,儿童少年出现了骨皮质发育逐渐增加的长期趋势.儿童少年骨皮质厚度平均增长值男孩为0.12±0.23 mm,女孩为0.10±0.11mm;掌骨皮质指数平均增长值男孩为1%±3%,女孩为2%±1%.2)1985-2005年,儿童少年身高、体重与骨皮质厚度、掌骨皮质指数的相关关系变化并不大;多元线性回归分析结果显示,1985--2005年,儿童少年身高、体重对掌骨皮质指数的影响基本上没有发生变化.     

Cortical and trabecular bone analysis of professional dancers using 3D-DXA: a case–control study

Given the lack of relevant data, the aim of this study was to examine femur cortical and trabecular bone in female and male professional ballet dancers. 40 professional ballet dancers and 40 sex- and age-matched non-exercising controls volunteered. Femoral bone density was scanned by dual-energy X-ray absorptiometry (DXA) scan. A 3D-DXA software was used to analyse trabecular and cortical bone. Anthropometry, maturation (Tanner staging), menstrual parameters (age at menarche and primary amenorrhea), energy availability and nutritional analysis (3-day record) were also assessed.Compared to non-exercising participants, dancers exhibited significantly higher volumetric density for integral, cortical and trabecular bone, and thicker cortex at the femur. Ballet dancers demonstrated lower body weight compared to controls (p < 0.01). Female dancers had their menarche later than controls, and the prevalence of primary amenorrhea were significantly higher in dancers than controls (p < 0.01). Dancer’s energy availability was below the normal range (<30 kcal/kgFFM/day). Despite the presence of certain osteoporosis risk factors such as low energy availability, primary amenorrhoea and lower body weight, professional ballet dancers revealed higher bone density for both cortical and trabecular bone compartments compared to controls.     

警惕青少年运动性骨折的潜在风险性

青少年运动性骨折是体育运动中经常发生的损伤症状。在运动实践中,人们往往把运动性骨折归结为外因——外力作用和内因——骨骼劳损作用的结果。而实际上,青少年运动性骨折还存在一个潜在的风险性原因——青少年骨质疏松症。本文通过对青少年运动性骨折及青少年骨质疏松的论述,旨在引起人们正确分析青少年运动性骨折的内在原发原因,以加强对青少年骨质疏松症的诊断和预防。     

骨形态发生蛋白在运动损伤中应用的研究进展

骨形态发生蛋白(bone mophorgenetic protein,BMP)是主要存在于骨和牙基质中的1种具有诱导成骨活性的蛋白质,自1971年Urist首次发现以来,许多学者对其进行了大量的研究,陆续有20多种被发现,同时有近10种BMP被鉴定和克隆并通过DNA重组技术实现重组表达[1]。BMP作为1种生长因子在运动损伤的治疗和修复过程中具有重要作用。我们认为BMP能够诱导多能间充质细胞转化为成骨细胞,从而在骨再生和骨折愈合中起重要作用,同时BMP在调节多种细胞的生长、分化和凋亡过程中起着关键作用。     

Bone dynamics: stress, strain and fracture

Bone is a dynamic tissue whose functional mass is controlled by the balance between the endocrine drive towards bone resorption and the mechanically-engendered drive towards bone formation. Strain is the key intermediate variable between loading forces and bone remodelling. Animal studies have shown that static loading of bone has no osteogenic effect; bone loss occurs as if there were no loading at all. However, dynamic loading, that is, cyclic change in internal strain, is strongly osteogenic, with relatively few cycles required for maximum effect. However, if a sufficient number of cycles is applied, repetitive loading can cause stress fractures. This number decreases as internal strains increase. Thus strain redistribution within bone, as caused by muscle fatigue or improper sports equipment, is a significant cause of fracture.