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11.
A normal time-course for the acquisition of sitting is essential. A delay in sitting may affect other developmental milestones, resulting in deficiencies in overall skill. Therefore, our aim was to identify variables whose measures at the very beginning of sitting would allow for the projection of the evolution of the sitting skill. Center of pressure data were collected from the postural sway of twenty-six typically developing infants while sitting on a force platform with a beginning ability to sit upright. Spatial, temporal and frequency variables of postural sway were obtained from both the medial/lateral and anterior/posterior directions of sway. Discriminant function analysis was conducted to identify potential predictors of the duration between onset and fully independent sitting. Gender (p = 0.025), median frequency (p = 0.006), and correlation dimension (p = 0.002) were identified to be predictive of grouping with 73.1% correct classification of the participating infants into short, mid, and long delay groups. In conclusion, measures taken at the earliest stage of sitting may allow the projection of the time-course to achieve independent sitting for typical infants. This approach may be useful for monitoring typical development.  相似文献   
12.
目的 比较仰卧位与侧卧位闭合复位髓内钉内固定治疗股骨干骨折的近期疗效. 方法 回顾性分析2007年6月至2010年9月采用髓内钉内固定的71例股骨干骨折患者资料,根据术中体位不同分为两组:仰卧位组33例,男26例,女7例;平均年龄为(39.2±9.6)岁;骨折AO分型:A型15例,B型9例,C型9例.侧卧位组38例,男29例,女9例;平均年龄为(42.2±10.1)岁;骨折AO分型:A型14例,B型10例,C型14例.记录并比较两组患者的手术时间、术中出血量、术中透视时间、改为切开复位内固定的病例数、近期并发症、住院时间及骨折愈合时间等. 结果 71例患者术后获12 ~ 26个月(平均20个月)随访.仰卧位组患者手术时间[(139.9 ±46.8) min]和术中透视时间[(191.4±78.6)s]较侧卧位组[(75.5±18.1)min、(93.3±27.1)s]长,术中出血量[(176.5±103.0)mL]较侧卧位组[(132.5±42.7) mL]多,两组间比较差异均有统计学意义(P<0.05).仰卧位组与侧卧位组患者住院时间和骨折愈合时间比较差异均无统计学意义(P>0.05).仰卧位组3例患者术中改为切开复位髓内钉固定.两组患者均未出现近期并发症.结论 侧卧位闭合复位髓内钉固定治疗股骨干骨折无需牵引床,具有手术时间短、创伤小及接受X线辐射量少等优点,是一种较好的术式选择.  相似文献   
13.
BackgroundBody-worn inertial measurement unit (IMU) sensors have been widely used in postural stability and balance studies because of their low cost and convenience. In most of these studies, a single IMU sensor is attached to a waist belt near the body’s center of mass. Some populations such as pregnant women, however, may find a waist belt challenging in terms of fit and comfort. For this reason it may be useful to identify an alternative location for placement of an IMU and a more comfortable means for attaching the sensor to the body.Research questionDoes placing an IMU sensor in a pendant worn around the neck permit discrimination between conditions with varying postural stability?MethodsTwenty-six healthy participants performed three standing tasks (double-leg, tandem, and single-leg standing) under eyes-open and eyes-closed vision conditions to preliminarily assess the ability of the pendant sensor to discriminate between balance conditions. Discrimination based upon data from a belt-mounted IMU was assessed in the same trials. Differences in standard deviation of acceleration components, sway area, and jerkiness due to trial condition and sensor were evaluated using analysis of variance followed by post hoc comparisons. These data were also incorporated into receiver-operator characteristic (ROC) curve analysis to assess the effectiveness of each sensor at discriminating between conditions.ResultsStability was found to vary across conditions, but there was no interaction between stability and sensor location (all p ≥ 0.323). ROC curve analysis showed that sensors in both locations were good discriminators between conditions.SignificancePlacing an IMU in a pendant may be feasible for studying and monitoring postural instability. This approach may be especially valuable when considering populations for which wearing a belt is uncomfortable.  相似文献   
14.
BackgroundFalls are common during pregnancy and present potential for injury to the pregnant individual and the baby.Research questionDo center of pressure characteristics during single leg stance differ between participants during and after pregnancy and nulligravida participants in the presence and absence of visual input?MethodsNineteen pregnant participants completed testing during the second trimester, the third trimester, and 4–6 months post-partum. Matched, nulligravida females completed testing once. All participants performed single leg stance on a force platform on each limb for up to 20 s with eyes open and with eyes closed. Center of pressure characteristics were compared between pregnant and nulligravida females using three separate 2 × 2 mixed way ANOVAs, one for each pregnancy time point (second trimester, third trimester, and post-partum) with Bonferroni correction.ResultsPregnant females demonstrated smaller single leg stance time with eyes closed during the third trimester. During the second and third trimester, pregnant participants demonstrated smaller sway and sway velocity across eyes open and eyes closed conditions. During the third trimester and post-partum, pregnant participants demonstrated greater median frequency of the center of pressure data. Pregnant participants also demonstrated smaller sample entropy in the anteroposterior direction during the second and third trimesters and in the mediolateral direction during the second trimester.SignificanceThe decreased total sway and sway velocity observed during pregnancy may reflect rigidity or a protective strategy during single limb stance. Additionally, center of pressure data were less smooth and more repetitive during pregnancy indicating robust differences in postural control strategies and potentially increased fall risk. Because single limb stance is a component of many activities of daily living, the single limb stance task may have clinical utility for testing or training balance in this population with a goal of decreasing falls.  相似文献   
15.
目的:研究放大镜和显微镜对口腔修复医生贴面牙体预备时体位的影响,从人体工程学角度对放大镜和显微镜的临床应用价值进行评价。方法:从北京大学口腔医院修复科选择20名口腔修复医生进行前瞻性、单盲、自身对照试验。研究过程中不告知受试者研究的试验假设和真实目的,每人依次在常规视野下(空白对照组)、2.5倍头戴式放大镜下(放大镜组)和8倍医用显微镜下(显微镜组)在仿头模内完成右上中切牙开窗型贴面牙体预备,试验过程中拍摄医生的侧面和正面体位照片。贴面牙体预备完成后,由医生本人利用视觉模拟评分法对自身体位进行主观评分,由两名专家利用侧面和正面体位照片按照“改良口腔医生体位评分表”对医生的体位进行专家评分。结果:空白对照组、放大镜组和显微镜组的主观评分分别为4.55±1.96、7.90±1.12、9.00±0.92,三组之间差异有统计学意义(P<0.05);专家评分分别为16.38±1.52、15.15±1.30、13.60±0.88,三组之间差异有统计学意义(P<0.05)。三组的专家评分在躯干前后向位置(1.33±0.41、1.03±0.11、1.00±0.00)、头颈前后向位置(2.75±0.38、2.13±0.36、1.23±0.38)、肘关节位置(1.38±0.43、1.40±0.45、1.13±0.22)和肩部高度(1.43±0.41、1.23±0.34、1.13±0.28)这4项评分上的差异有统计学意义(P<0.05),其中,在头颈前后向位置和肘关节位置方面,放大镜组与显微镜组之间的差异有统计学意义(P<0.05)。结论:放大镜和显微镜均能改善口腔修复医生牙体预备时的体位,其中显微镜的效果更好,从人体工程学的角度二者均具有较高的临床应用价值。  相似文献   
16.
蔡弢艺  陈志达  张哲明  林斌  蒋元杰 《骨科》2023,14(6):495-500
目的 对比后路体位复位联合椎弓根钉撑开复位固定治疗A3、A4型胸腰椎骨折的疗效。方法 回顾性分析我院2019年1月至2021年12月采用后路体位复位联合椎弓根钉撑开复位固定治疗的66例A3、A4型胸腰椎压缩骨折病人的临床及影像学资料。其中男40例,女26例,(48.14±5.73)岁(26~60岁)。A3型骨折37例纳入A3组,A4型骨折29例纳入A4组。采用疼痛视觉模拟量表(VAS)评分与Oswestry功能障碍指数(ODI)评估手术临床效果,比较两组伤椎前缘高度比、伤椎后凸角及局部后凸Cobb角等。结果 病人随访11~18个月,术后切口均一期愈合,未见感染、神经损伤、内固定失效等并发症。两组术后随访VAS评分、ODI指数均较术前明显改善,差异有统计学意义(P<0.05),但组间差异无统计学意义(P>0.05)。A3组术后3天的伤椎前缘高度比、伤椎后凸角分别为89.14%±4.79%、6.67°±2.13°,均较术前显著改善,且显著优于A4组的85.72%±5.17%、8.36°±2.49°,在随访期内,各项数值均显著优于术前,且组间比较,差异均有统计学意义(P<0.05)。两组术后及随访期内,局部后凸Cobb角均较术前显著改善,但组间差异并无统计学意义(P>0.05)。结论 后路体位复位联合椎弓根钉撑开复位固定治疗A3、A4型胸腰椎骨折均能取得良好的临床疗效,且A3型骨折在伤椎前缘高度比、伤椎后凸角改善方面均优于A4型骨折。  相似文献   
17.
The nasolabial fold is a significant facial landmark. Its size, shape, and symmetry are important in facial reanimation surgery, while effacement is an important goal in rejuvenation surgery. However, quantitative data for the nasolabial fold volume (NLFV) and depth is still unavailable. We present a new method of measurement using 3D color speckle stereophotogrammetry and its application in the assessment of NLFV. The VECTRA-3D system was validated to determine its minimum resolution and accuracy. Normal volunteers aged 13–84 years (n = 87) were imaged in repose. Mother–daughter pairs (n = 15, aged 13–61) were imaged in the upright and supine positions. All data were processed using custom software and analyzed by linear regression and nonparametric tests as appropriate. NLFV varied from 0.0026 to 0.2306 ml. There was significant correlation between NLFV and age (r = 0.7269, p < 0.0001). Men had significantly higher NLFV than women across all ages. There was no significant difference between the left and right NLFV. NLFV altered significantly from upright to supine in all subjects (p = 0.0012). However, the mothers increased their NLFV by 32% from supine to upright postures, which was a greater change than observed in their daughters. We have demonstrated a rapid, objective, and non-invasive assessment tool for facial reanimation and rejuvenation surgery. We have quantified the effects of age and posture on NLFV, and the efficacy and longevity of rejuvenation procedures are currently under investigation.  相似文献   
18.
This study investigated the influence of attention on the sensory integration component of postural control in young and older adults. Eighteen young and 18 older healthy subjects performed information-processing tasks during different postural challenge conditions. Postural conditions included seated, standing on a firm surface, standing on a sway-referenced floor, and standing on a sway-referenced floor while viewing a sway-referenced scene. During each condition, reaction time (RT) was measured during two simple and one inhibitory RT tasks. For the inhibitory task, the time required to inhibit an action was derived, termed the inhibitory time (IT). Performing a RT task was associated with increased postural sway in older subjects, but not in young subjects. The greatest influence of RT task on sway of older subjects was found during the sway-referenced floor/sway-referenced scene condition. Conversely, postural condition had an influence on RT task performance in both young and older subjects. The IT was increased in both young and older subjects only during the sway-referenced floor/scene condition. These results suggest that the sensory integration component of postural control in particular seems to require attention. Further, our data suggest that attentional processes related to inhibitory control are engaged when sensory integration requirements are high.  相似文献   
19.
体位改变对胸科手术病人双腔支气管导管位置的影响   总被引:5,自引:0,他引:5  
目的 探讨体位改变对双腔支气管导管位置的影响。方法 择期开胸手术病人100例,ASAⅠ或Ⅱ级,随机分为两组(n=50):左双腔支气管导管组(L-DLT组)及右双腔支气管导管组(R—DLT组)。全麻诱导后分别插入左、右双腔支气管导管,用纤维支气管镜(FOB)确定导管位置。病人体位由平卧位改为侧卧位后,用听诊法和FOB再次检查、确定导管位置。记录结果和DLT深度。结果 与平卧位相比,L-DLT组的DLT深度均变浅(P〈0.05);R-DLT组的置入深度变化男性差异无统计学意义(P〉0.05),女性变浅(P〈0.05)。体位改变后,听诊法判断DLT位置不满意的13例,其中L-DLT组为5例(10%),R-DLT组为8例(16%)。FOB检查导管位移32例,其中L-DLT组管端位移12例(24%),包括严重位移3例(6%);R—DLT组管端位移20例(40%),包括严重位移7例(14%)。位移率和严重位移率R-DLT组均高于L-DLT组(P〈0.05)。结论 体位改变对DLT位置有较大影响。FOB检查的准确性明显高于听诊法。  相似文献   
20.
A longitudinal study was undertaken to analyse the development of posture and spinal mobility during growth and its relationship to low back pain and sports activities. A total of 90 children were examined at 5-6 years of age and re-examined at 15-16. Sagittal configuration and mobility were measured using Debrunner's kyphometer. Information about pain and activities was acquired by interview with the parents of the 5- to 6-year-olds and by a questionnaire to the 15- to 16-year-olds. Posture changed significantly during the study period: thoracic kyphosis increased by 6 degrees and lumbar lordosis increased by 6 degrees. The relationship between kyphosis and lordosis was independent of gender at age 5-6, but kyphosis in relation to lordosis was significantly lower in girls among the 15- to 16-year-olds. The total sagittal mobility of the spine decreased significantly during the 10-year study period: in the thoracic spine by as much as 27 degrees and in the lumbar spine by 4 degrees. About one-third of the children at the age of 15-16 years stated that they had occasional low back pain. This complaint was more frequent in those stating they had suffered some type of back injury, but low back pain was not related to gender, regular physical training, posture or spinal mobility. The results of the study showed that kyphosis and lordosis increased and mobility decreased in the 90 children who were examined both at age 5-6 and 15-16 years. The relationship between kyphosis and lordosis decreased in girls but not in boys. Occasional low back pain was reported by 38% of the children at the age of 15-16 years, but back pain was not related to posture, spinal mobility or physical activity.  相似文献   
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