慢性睡眠剥夺对颞下颌关节微结构的影响

目的:研究慢性睡眠障碍对大鼠颞下颌关节微结构的影响。方法:采用改良多平台法(MMPM)建立睡眠剥夺模型,将90只Wistar大鼠随机分为3组(n=30),分别为小平台组、网格组和对照组。小平台组和网格组大鼠接受每天18 h的睡眠剥夺和6 h间歇期(10:00—16:00),间歇期大鼠正常笼养。实验第7、14和21天时分别行动物行为学观察、旷场试验和动物血浆检测,并通过HE染色和扫描电镜观察颞下颌关节微结构的变化。结果:与对照组和网格组相比,小平台组大鼠血清促肾上腺激素(ACTH)和皮质醇(CORT)水平均增高(P<0.05),髁突软骨HE染色显示软骨细胞层次及厚度改变;扫描电镜结果显示关节盘表面纤维排列松散。结论:慢性睡眠障碍可能导致颞下颌关节微结构发生病理性改变。     

布鲁杆菌性化脓性关节炎1例

布鲁菌病是系统性感染性疾病,临床表现多样,在非流行区易被忽视。本病以骨关节受累常见,关节症状多数为反应性关节炎,以单关节化脓性关节炎为首发表现的病例少见。本文报道1例布鲁杆菌性化脓性单膝关节炎的临床表现和诊疗情况。     

MMP-1、MMP-3 和MMP-13在慢性睡眠剥夺所致颞下颌关节损伤中的变化

目的：观察MMP-1、MMP-3 和MMP-13 在慢性睡眠剥夺所致颞下颌关节损伤中表达的变化,探讨慢性睡眠剥夺所致颞下颌 关节损伤的可能机制。方法：采用改良多平台(MMPM)建立大鼠慢性睡眠剥夺模型,将90 只成年雄性Wastar 大鼠随机分为小平 台组、网格组和对照组。小平台组和网格组大鼠接受每天18 h的睡眠剥夺和6 h间歇期(10:00-16:00),间歇期大鼠正常笼养。实验 第7、14 和21 d时分别观察动物的行为学观察、检测动物血浆皮质醇(CORT)和促肾上腺皮质激素(ACTH)水平检测,通过免疫印 迹法和实时定量聚合酶链反应(PRC)检测颞下颌关节软骨中MMP-1、MMP-3 和MMP-13 的蛋白和mRNA表达,并通过HE 染色 法观察颞下颌关节结构的变化。结果：与对照组和网格组大鼠相比,小平台组大鼠第14 d和21 d 时髁突软骨中间部位表面纤维 在出现明显的炎症、松解及脱落现象;第21天时的血浆ACTH 和CORT 水平均显著高于网格组和对照组,差异有统计学意义 (P<0.05);第7、14、21 d时关节软骨MMP-1 和MMP-13 蛋白和mRNA 的表达水平均显著上调(P<0.05)。结论：慢性睡眠剥夺所致 的颞下颌关节损伤可能与关节软骨中MMP-1、MMP-3 和MMP-13 的表达上调有关。     

入伍新训中膝关节损伤的特点与防治研究

目的：通过对某部新入伍官兵训练中膝关节损伤发生原因、特点进行流行性病学调查和分析,为合理训练,预防损伤发生和 治疗相关伤病提供指导依据。方法：对某部2013 年度450 名新入伍官兵的训练伤发病情况进行统计分析,重点分析膝关节损伤 发生率、伤病类型和致伤原因,并对其严重者进行关节镜治疗,观察和分析术后随访效果。结果：某部新兵的训练伤发生率为 20.0%。以关节急性扭伤最为多见,占81.1%。其中膝关节损伤共发生32 例,占训练伤发病率为7.1%,占训练伤发病率43.8%,其 中膝关节周围肌肉损伤20 例、交叉韧带损伤1 例、半月板损伤9 例、侧副韧带损伤2 例。致伤率最高的前3 位科目是5000 米负 重跑、跨越障碍训练、格斗训练,共27 例,占膝关节训练伤总数的84.4%。所有受伤患者中,12 例行手术治疗,20 例给予石膏、支具 固定、休息等保守治疗。经随访所有患者均得到较好的功能恢复。结论：对于新兵膝关节训练伤预防工作非常重要,避免致残;关 节镜手术技术的进步对于膝关节军事训练伤治疗有良好的效果。     

In vivo baseline measurements of hip joint range of motion in suspensory and nonsuspensory anthropoids

Hominoids and atelines are known to use suspensory behaviors and are assumed to possess greater hip joint mobility than nonsuspensory monkeys, particularly for range of abduction. This assumption has greatly influenced how extant and fossil primate hip joint morphology has been interpreted, despite the fact that there are no data available on hip mobility in hominoids or Ateles. This study uses in vivo measurements to test the hypothesis that suspensory anthropoids have significantly greater ranges of hip joint mobility than nonsuspensory anthropoids. Passive hip joint mobility was measured on a large sample of anesthetized captive anthropoids (nonhuman hominids = 43, hylobatids = 6, cercopithecids = 43, Ateles = 6, and Cebus = 6). Angular and linear data were collected using goniometers and tape measures. Range of motion (ROM) data were analyzed for significant differences by locomotor group using ANOVA and phylogenetic regression. The data demonstrate that suspensory anthropoids are capable of significantly greater hip abduction and external rotation. Degree of flexion and internal rotation were not larger in the suspensory primates, indicating that suspension is not associated with a global increase in hip mobility. Future work should consider the role of external rotation in abduction ability, how the physical position of the distal limb segments are influenced by differences in ROM proximally, as well as focus on bony and soft tissue differences that enable or restrict abduction and external rotation at the anthropoid hip joint. Am J Phys Anthropol 153:417–434, 2014. © 2013 Wiley Periodicals, Inc.     

Articular to diaphyseal proportions of human and great ape metatarsals

This study proposes a new way to use metatarsals to identify locomotor behavior of fossil hominins. Metatarsal head articular dimensions and diaphyseal strength in a sample of chimpanzees, gorillas, orangutans, and humans (n = 76) are used to explore the relationships of these parameters with different locomotor modes. Results show that ratios between metatarsal head articular proportions and diaphyseal strength of the hallucal and fifth metatarsal discriminate among extant great apes and humans based on their different locomotor modes. In particular, the hallucal and fifth metatarsal characteristics of humans are functionally related to the different ranges of motion and load patterns during stance phase in the forefoot of humans in bipedal locomotion. This method may be applicable to isolated fossil hominin metatarsals to provide new information relevant to debates regarding the evolution of human bipedal locomotion. The second to fourth metatarsals are not useful in distinguishing among hominoids. Further studies should concentrate on measuring other important qualitative and quantitative differences in the shape of the metatarsal head of hominoids that are not reflected in simple geometric reconstructions of the articulation, and gathering more forefoot kinematic data on great apes to better understand differences in range of motion and loading patterns of the metatarsals. Am J Phys Anthropol 143:198–207, 2010. © 2010 Wiley‐Liss, Inc.     

Activation of the hypoxia-inducible factor-1 in overloaded temporomandibular joint, and induction of osteoclastogenesis

Vascular endothelial growth factor (Vegf) was previously shown to be expressed specifically in the condylar cartilage of temporomandibular joint-osteoarthritis (TMJ-OA) model rats. Here we demonstrate for the first time that hypoxia-inducible factor-1α (Hif-1α) is activated in mature chondrocytes of temporomandibular joint-osteoarthritis (TMJ-OA) model rat by mechanical overload, and that activated Hif-1 in chondrocytes can induce osteoclastogenesis via repression of osteoprotegerin (Opg) expression.In rat TMJs, degeneration of the condylar cartilage became prominent in proportion to the duration of overloading. Hif-1α expression was observed specifically in mature and hypertrophic chondrocytes, and Hif-1α-positivity, level of Vegf expression, and tartrate-resistant acid phosphatase (TRAP)-positive cell numbers all increased in the same manner. When ATDC5 cells induced differentiation by insulin were cultured under hypoxia, Hif-1α induction was observed in mature stage, but not in immature stage. Inductions of Hif-1-target genes showed a similar expression pattern. In addition, expression of Opg decreased in hypoxia, and Hif-1α played a role, in part, in its regulation.     

Effect of surface roughness on squeeze film poroelastic bearings with special reference to synovial joints

A simplified mathematical model has been developed for understanding the combined effects of surface roughness and couple stresses on lubrication aspects of synovial joints. The modified Reynolds equation which incorporates the elastic as well as randomized surface roughness structure of cartilage with couple-stress fluid as lubricant is derived. The mean pressure, load carrying capacity and time of approach as functions of film thickness during normal articulation of joints are obtained by using Christensen stochastic theory with the assumption that the roughness asperity heights are to be small compared to the film thickness. The effects of surface roughness and elasticity are considerably pronounced for the poroelastic bearings with couple-stress fluid as lubricant compared with classical case.     

Bone density spatial patterns in the distal radius reflect habitual hand postures adopted by quadrupedal primates

Primates adopt diverse hand postures during terrestrial and above-branch quadrupedal locomotion--knuckle-walking, digitigrady, and palmigrady--that incorporate varying degrees of wrist dorsiflexion (i.e., extension). Although relationships between hand postures, wrist joint range of motion, and the external properties of wrist bones (e.g., surface morphology) have been examined, the relationship between hand postures and the internal properties of wrist bones (e.g., bone density) remains largely unexplored. Because articular joint surfaces transmit mechanical loads between conjoining limb bones, measures of density (e.g., magnitudes and patterns) in the subchondral cortical plate of bone of the distal radius can be used to evaluate load regimes experienced by the wrist joint in different hand postures. We assessed apparent (i.e. optical) density patterns in several extant catarrhine primate taxa partitioned into different hand posture groups: knuckle-walking apes, digitigrade monkeys, and palmigrade monkeys. Computed tomography osteoabsorptiometry (CT-OAM) was used to construct maximum intensity projection (MIP) maps of apparent densities. High apparent density areas were characterized relative to a dorsal-volar reference plane and compared across hand posture groups. All groups had large percentage areas of high apparent density in the dorsal region of the distal radial articular surface. Only knuckle-walking apes, however, had a large percentage area of high apparent density in the volar region of the distal radial articular surface. These patterns are consistent with radiocarpal articulations in specific hand postures as evidenced by available radiographic data and suggest that the different habitual hand postures adopted by monkeys and African apes during quadrupedal locomotion have different stereotypic loading patterns. This has implications for understanding the functional morphology and evolution of knuckle-walking and digitigrade hand postures in primates.     

Anterior hip joint force increases with hip extension, decreased gluteal force, or decreased iliopsoas force

Abnormal or excessive force on the anterior hip joint may cause anterior hip pain, subtle hip instability and a tear of the acetabular labrum. We propose that both the pattern of muscle force and hip joint position can affect the magnitude of anterior joint force and thus possibly lead to excessive force and injury. The purpose of this study was to determine the effect of hip joint position and of weakness of the gluteal and iliopsoas muscles on anterior hip joint force. We used a musculoskeletal model to estimate hip joint forces during simulated prone hip extension and supine hip flexion under four different muscle force conditions and across a range of hip extension and flexion positions. Weakness of specified muscles was simulated by decreasing the modeled maximum force value for the gluteal muscles during hip extension and the iliopsoas muscle during hip flexion. We found that decreased force contribution from the gluteal muscles during hip extension and the iliopsoas muscle during hip flexion resulted in an increase in the anterior hip joint force. The anterior hip joint force was greater when the hip was in extension than when the hip was in flexion. Further studies are warranted to determine if increased utilization of the gluteal muscles during hip extension and of the iliopsoas muscle during hip flexion, and avoidance of hip extension beyond neutral would be beneficial for people with anterior hip pain, subtle hip instability, or an anterior acetabular labral tear.