The influence of basic body and hand anthropometry on the results of different throwing tests in young handball and basketball players

The aim of this study was to investigate the relationships between basic body and specific hand anthropometric parameters with some specific and non-specific throw test results in young male handball and basketball players. The subjects included 34 handball and 38 basketball players of the 10-11 years old age group, 39 handball and 22 basketball players of the 12-13 years old age group and 39 handball players of the 14-15 years old age group. Body height and body mass, arms' span, height with outstretched hands and sitting height were the basic anthropometric parameters to be measured. For hand anthropometry, 15 specific hand parameters were measured using the method presented by Visnapuu & Jürim?e (2007). Stepwise multiple regression analysis indicated that medicine ball throw results in the youngest age group are highly dependent on the body height (handball players) and body mass (basketball players). In the middle age group, the most important parameter from the hand anthropometry is TL (handball) or height with outstretched hands (basketball). In the oldest group of handball players, the medicine ball throw results were dependent on the P2 from hand anthropometry and sitting height. Quite different anthropometric parameters appeared to influence the handball or basketball throw results. In the youngest age group, most important were body height (handball) or LFL (basketball). In the middle age group, the most important was height with outstretched hands and in the oldest handball players LFL and sitting height. Handball or basketball pass on speed depended on the combination of body mass and FS5 and body height with height with outstretched hands (even 61.40%, R2 x 100) in the oldest age group. The results of passing the handball or basketball on precision were dependent on body height and P3 or P1 among basketball players in the youngest group. In the middle age group the combination of FS3 and body mass and LFL and height with outstretched hands were the most influential. Anthropometric parameters influence on the passing of the ball on speed or precision is lower in handball players compared with basketball players. Our conclusion is that the basic anthropometric parameters are slightly more important than hand anthropometry that influenced different throw tests results in young handball and basketball players.     

Measurement and modelling of x-direction apparent mass of the seated human body-cushioned seat system

For modelling purposes and for evaluation of driver's seat performance in the vertical direction various mechano-mathematical models of the seated human body have been developed and standardized by the ISO. No such models exist hitherto for human body sitting in an upright position in a cushioned seat upper part, used in industrial environment, where the fore-and-aft vibrations play an important role. The interaction with the steering wheel has to be taken into consideration, as well as, the position of the human body upper torso with respect to the cushioned seat back as observed in real driving conditions. This complex problem has to be simplified first to arrive at manageable simpler models, which still reflect the main problem features. In a laboratory study accelerations and forces in x-direction were measured at the seat base during whole-body vibration in the fore-and-aft direction (random signal in the frequency range between 0.3 and 30 Hz, vibration magnitudes 0.28, 0.96, and 2.03 ms(-2) unweighted rms). Thirteen male subjects with body masses between 62.2 and 103.6 kg were chosen for the tests. They sat on a cushioned driver seat with hands on a support and backrest contact in the lumbar region only. Based on these laboratory measurements a linear model of the system-seated human body and cushioned seat in the fore-and-aft direction has been developed. The model accounts for the reaction from the steering wheel. Model parameters have been identified for each subject-measured apparent mass values (modulus and phase). The developed model structure and the averaged parameters can be used for further bio-dynamical research in this field.     

Sitting height: An analysis of five measurement techniques

Five methods of obtaining sitting height were compared by taking triple trials of each. Three methods required that the subjects be seated on a table, the fourth had them sitting on the floor against a wall, and the fifth placed them in a recumbent position. Three trials of the first method were obtained without stretching and with the feet unsupported. These were followed by stretching techniques with subjects seated on the table, first with the feet unsupported and then with them supported, then with the subjects sitting on the floor, and finally with the subjects in the recumbent position. All methods were shown to be precise, with the smallest absolute measurements and highest technical error of measurement noted in the floor seated method. There was a tendency for females to yield greater values from being stretched, and for males to have greater values in the recumbent position.     

Characterization of febrile seizures and febrile seizure susceptibility in mouse inbred strains

Febrile seizures (FS) are the most prevalent seizures in children. Although FS are largely benign, complex FS increase the risk to develop temporal lobe epilepsy (TLE). Studies in rat models for FS have provided information about functional changes in the hippocampus after complex FS. However, our knowledge about the genes and pathways involved in the causes and consequences of FS is still limited. To enable molecular, genetic and knockout studies, we developed and characterized an FS model in mice and used it as a phenotypic screen to analyze FS susceptibility. Hyperthermia was induced by warm air in 10- to 14-day-old mice and induced FS in all animals. Under the conditions used, seizure-induced behavior in mice and rats was similar. In adulthood, treated mice showed increased hippocampal Ih current and seizure susceptibility, characteristics also seen after FS in rats. Of the seven genetically diverse mouse strains screened for FS susceptibility, C57BL/6J mice were among the most susceptible, whereas A/J mice were among the most resistant. Strains genetically similar to C57BL/6J also showed a susceptible phenotype. Our phenotypic data suggest that complex genetics underlie FS susceptibility and show that the C57BL/6J strain is highly susceptible to FS. As this strain has been described as resistant to convulsants, our data indicate that susceptibility genes for FS and convulsants are distinct. Insight into the mechanisms underlying seizure susceptibility and FS may help to identify markers for the early diagnosis of children at risk for complex FS and TLE and may provide new leads for treatment.     

Urinating Standing versus Sitting: Position Is of Influence in Men with Prostate Enlargement. A Systematic Review and Meta-Analysis

Background

It is suggested that the body posture during urination can influence urodynamic parameters in patients with Lower Urinary Tract Symptoms (LUTS) to an extent approaching pharmacological interventions. In this article, the influence of body position during micturition on maximum urinary flow rate (Qmax), voiding time (TQ) and post-void residual volume (PVR) in healthy males and patients with LUTS is analyzed by means of a systematic review and meta-analysis.

Evidence Acquisition

A systematic search was conducted in 14 medical databases. Studies comparing urodynamic parameters in standing versus sitting position were eligible for inclusion. Studies were stratified according to health status of included male participants: healthy individuals and patients with LUTS. Standardized mean differences for Qmax, TQ and PVR were pooled in a random effects model.

Results

Eleven articles were included. In men with LUTS, a significantly lower PVR (−24.96 ml; 95%CI −48.70 to −1.23) was shown in sitting position compared to standing. In accordance, Qmax was increased (1.23 ml/s; 95%CI −1.02 to 3.48), and TQ was decreased (−0.62 s; 95%CI −1.66 to 0.42) in sitting position, although these differences did not reach statistical significance. In healthy men, Qmax (0.18 ml/s; 95% CI −1.67 to 2.02), TQ (0.49 s; 95%CI −3.30 to 4.27) and PVR (0.43 ml; 95%CI −0.79 to 1,65) were similar in sitting and standing position.

Conclusion

For healthy men, no difference is found in any of the urodynamic parameters. In patients with LUTS, the sitting position is linked with an improved urodynamic profile.     

Effect of fenitrothion on dipalmitoyl and 1-palmitoyl-2-oleoylphosphatidylcholine bilayers

The effects of the organophosphorous insecticide fenitrothion (phosphorothioic acid, O,O-dimethyl O-(3-methyl-4-nitrophenyl) ester; FS) on the physical state of pure dipalmitoyl (DPPC) and 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) membranes were investigated. FS lowers the phase transition temperature of DPPC. It has no large effects on the DPPC gel phase, but it increases the order of the liquid-crystalline state of DPPC and POPC. FS also decreases 1,6-diphenyl-1,3,5-hexatriene (DPH) lifetime (tau) in the DPPC and POPC liquid-crystalline states. Since a direct quenching of DPH emission by FS was ruled out, tau shortening is assigned to an increased water penetration in the bilayer. The effect of FS is different from most perturbing agents for which an increased order is accompanied by a higher tau. Furthermore, quenching of DPH by KI was increased by FS in POPC liposomes indicating an increased accessibility of the quencher to the hydrophobic core where DPH distributes. The effect of FS on dipole relaxation at the hydrophilic-hydrophobic interface of POPC bilayers was studied with 2-dimethylamino-6-lauroylnaphthalene (Laurdan). FS produces a decrease in Laurdan tau and a narrowing of its emission band. FS significantly increases the generalized polarization values at both emission band ends. These results indicate that FS may allow the coexistence of microdomains that have different physical properties.     

Effect of lung volume and positional changes on pulmonary diffusing capacity and its components.

Normal subjects have a larger diffusing capacity normalized per liter alveolar volume (DL/VA) in the supine than in the sitting position. Body position changes total lung diffusing capacity (DL), DL/VA, membrane conductance (Dm), and effective pulmonary capillary blood volume (Qc) as a function of alveolar volume (VA). These functions were studied in 37 healthy volunteers. DL/VA vs. VA yields a linear relationship in sitting as well as in supine position. Both have a negative slope but usually do not run parallel. In normal subjects up to 50 yr old DL/VA and DL increased significantly when subjects moved from a sitting to a supine posture at volumes between 50 and 100% of total lung capacity (TLC). In subjects greater than 50 yr old the responses of DL/VA and DL to change in body position were not significant at TLC. Functional residual capacity (FRC) decreases and DL/VA increases in all normal subjects when they change position from sitting to supine. When DL/VA increases more than predicted from the DL/VA vs. VA relationship in a sitting position, we may infer an increase in effective Qc in the supine position. In 56% of the volunteers, supine DL was smaller than sitting DL despite a higher DL/VA at FRC in the supine position because of the relatively larger decrease in FRC. When the positional response at TLC is studied, an estimation obtained accidentally at a volume lower than TLC may influence results. Above 80% of TLC, Dm decreased significantly from sitting to supine. Below this lung volume the decrease was not significant. The relationship between Qc and VA was best described by a second-order polynomial characterized by a maximum Qc at a VA greater than 60% of TLC. Qc was significantly higher in the supine position than in the sitting position, but the difference became smaller with increasing age. In observing the sitting and supine positions, we saw a decrease in maximum Qc normalized per square meter of body surface area with age.     

Heparin-mediated dimerization of follistatin

Heparin and heparan sulfate (HS) are highly sulfated polysaccharides covalently bound to cell surface proteins, which directly interact with many extracellular proteins, including the transforming growth factor-β (TGFβ) family ligand antagonist, follistatin 288 (FS288). Follistatin neutralizes the TGFβ ligands, myostatin and activin A, by forming a nearly irreversible non-signaling complex by surrounding the ligand and preventing interaction with TGFβ receptors. The FS288-ligand complex has higher affinity than unbound FS288 for heparin/HS, which accelerates ligand internalization and lysosomal degradation; however, limited information is available for how FS288 interactions with heparin affect ligand binding. Using surface plasmon resonance (SPR) we show that preincubation of FS288 with heparin/HS significantly decreased the association kinetics for both myostatin and activin A with seemingly no effect on the dissociation rate. This observation is dependent on the heparin/HS chain length where small chain lengths less than degree of polymerization 10 (dp10) did not alter association rates but chain lengths >dp10 decreased association rates. In an attempt to understand the mechanism for this observation, we uncovered that heparin induced dimerization of follistatin. Consistent with our SPR results, we found that dimerization only occurs with heparin molecules >dp10. Small-angle X-ray scattering of the FS288 heparin complex supports that FS288 adopts a dimeric configuration that is similar to the FS288 dimer in the ligand-bound state. These results indicate that heparin mediates dimerization of FS288 in a chain-length-dependent manner that reduces the ligand association rate, but not the dissociation rate or antagonistic activity of FS288.     

Neurophysiologic measurement of continuity in the sleep of fetuses during the last week of pregnancy and in newborns

Our aim was to measure the correlation between fetal electrocardiographic (FECG) recordings of low-risk pregnancies and polysomnographic (PSG) study parameters in low-risk infants born at term as a measurement of perinatal sleep-development continuity.We designed a short, prospective, observational follow-up of physiologic parameters between fetuses and newborns. We studied 10 fetuses from low-risk pregnant female out-patients and the same subjects as low-risk newborns delivered at term. Fetal state (FS) was defined in FECG recordings reassembling the following: fetal state I (quiet sleep or QS); fetal state II (active sleep or AS); fetal state III (quiet waking), and fetal state IV (active waking). Percentages of AS, QS, and wakefulness in PSG studies of newborns were also determined.Comparisons of FS I with QS showed a significant reduction in QS, while comparison of FS II with AS showed significant reduction in AS. Negative correlations were found between FS I with QS, and FS II with AS. Number of cycles in FECG recordings and PSG sleep cycles also demonstrated significant correlation.In conclusion our data showed partial but significant sleep function continuity from fetal to neonatal period.     

Effects of room temperature and body position change on cerebral blood volume and center-of-foot pressure in healthy young adults

This study aimed to examine the effects of room temperature and body position changes on cerebral blood volume, blood pressure and center-of-foot pressure (COP). Cerebral oxygenation kinetics and blood pressure were measured by near infrared spectroscopy (NIRS) and volume-compensation, respectively, in 9 males and 9 females after rapid standing from sitting and supine positions in low (12 degrees C) or normal (22 degrees C) room temperatures. COP was also measured in a static standing posture for 90 s after rapid standing. The total hemoglobin (Hb) decreased just after standing. Blood pressure after standing at normal temperature tended to decrease immediately but at low temperature tended to decrease slightly and then to increase greatly. The decreasing ratio of total Hb and blood pressure upon standing from a supine position at normal room temperatures was the largest of any condition. Total Hb recovered to a fixed level approximately 25 sec after standing from a sitting position and approximately 35 sec after standing from a supine position. All COP parameters after standing tended to change markedly in the supine position compared to the sitting position, especially at normal temperatures. The COP parameters after standing in any condition were not significantly related to the decreasing ratio of total Hb but were related to the recovery time of total Hb after standing. In conclusion, decreasing ratios of total Hb and blood pressure after standing from a supine position at normal temperatures were large and may affect body sway.     

A multi-body model for comparative study of cervical traction simulation – comparison between inclined and sitting traction

A computer simulation model was developed to compare the result of cervical traction therapy in inclined and sitting traction positions. The behavior of the model was shown to match with the intervertebral changes in the upper and lower spine from the data of a radiographic experiment. Both the results of the experiment and the simulation also showed that in the inclined position, the amount of posterior separations in the upper cervical spine remains constant regardless of traction angle, while the posterior separations at lower cervical spine increases along with traction angles. Using the simulation model, parametric studies were conducted to investigate the intervertebral space changes in response to different traction angles in the inclined and sitting positions. When using the sitting position, the subject’s hip joint stiffness was shown to cause larger variations in the intervertebral space than in the inclined position. In addition, variations in the tension/compression stiffness was shown to cause the largest changes in the resulting separations in both positions but the variations in anterior space changes were larger in the sitting position. Our study suggests that the inclined position is less sensitive to variations in the subject's body parameters and is able to provide a more reliable and predictable traction result than the sitting position.     

Nonstationarity and duration of the cardiac interval time series in assessing the functional state of operator personnel

The influence of nonstationarity in the time series of cardiac intervals on the assessment of the functional state (FS) of operator personnel was analyzed with a three-factor model of heart rhythm variability (HRV). ECG recordings were made in supine position at rest and in the sedentary position before and after important operator testing. In all three cases, the FS assessments were not influenced by nonstationarity of the input data. The effect of nonstationarity was also negligible for some particular HRV indices. Reliable assessments could be obtained from relatively short samples (256 down to 32 RR intervals) with prior norming of the factor indices for the corresponding segment length. The influence of the time series duration on the HRV indices was examined in various FSs; stable indices and proper recording conditions were determined.     

Accelerometer-based body-position sensing for ambulatory electrocardiographic monitoring

Our objective is to validate the ability of 3 appropriately placed accelerometers to determine body position during ambulatory electrocardiographic (ECG) monitoring and to demonstrate the clinical applicability of this method. During ambulatory (Holter) monitoring, the ability to know a patient's position (lying down, sitting, standing, or changing from one position to another) is important in the evaluation of common symptoms such as dizziness, palpitations, and syncope. Changes in body position are also known to alter the electrical axis of the heart, resulting in artifactual changes in QRS amplitude and ST-segment morphology. We have developed an ambulatory patient-monitoring instrument that, through the use of microfabricated accelerometers, can simultaneously record body-position information and 2 channels of ECG data. The accelerometers measure the effects of gravity and dynamic acceleration, allowing determination of a patient's orientation and movements. The accelerometer and ECG signals are input to a portable recorder and are filtered and digitized. Algorithms were developed to automatically determine body position. Ten healthy volunteers wore the device for 1 hour and followed a protocol of standing, sitting, walking, lying supine, and lying in the left and right lateral decubitus positions. An observer manually recorded times of position changes. Data were recorded and analyzed using software designed with MATLAB. The ability of the accelerometers and computer algorithms to determine body position was analyzed in terms of the sensitivity and specificity for each body position. The sensitivities for sitting, standing, walking, lying supine, lying right, and lying left were 98.8%, 99.2%, 95.5%, 99.1%, 98.9%, and 94.8%, respectively. The specificities were 99.7%, 99.4%, 99.6%, 99.0%, 99.8%, and 99.9%, respectively. The use of microfabricated accelerometers is a clinically feasible method to determine body position and can be applied to future studies correlating body position with ECG or other physiologic data.     

Analysis of the Interaction between Heparin and Follistatin and Heparin and Follistatin-Ligand Complexes Using Surface Plasmon Resonance

Heparin and related heparan sulfate interact with a number of cytokines and growth factors, thereby playing an essential role in many physiological and pathophysiological processes by involving both signal transduction and the regulation of the tissue distribution of cytokines/growth factors. Follistatin (FS) is an autocrine protein with a heparin-binding motif that serves to regulate the cell proliferative activity of the paracrine hormone, and member of the TGF-β family, activin A (ActA). Follistatin is currently under investigation as an antagonist of another TGF-β family member, myostatin (Mstn), for the promotion of muscle growth in diseases associated with muscle atrophy. In this study, we employ surface plasmon resonance (SPR) spectroscopy to dissect the binding interactions between the heparin polysaccharide and both free follistatin (FS288) and its complexes (FS288-ActA and FS288-Mstn). FS288 complexes show much higher heparin binding affinity than FS288 alone. SPR solution competition studies using heparin oligosaccharides showed that the binding of FS288 and its complex to heparin is dependent on chain length. Full chain heparin or large oligosaccharides, having 18-20 sugar residues, show the highest binding activity for FS288 and the FS288-ActA complex, whereas smaller heparin molecules could interact with the FS288-Mstn complex. These interactions were also analyzed in normal physiological buffers and at different salt concentrations and pH values. Unbound follistatin was much more sensitive to all salt concentrations of >150 mM. The binding of heparin to the FS288-ActA complex was disrupted at 500 mM salt, whereas it was actually strengthened for the FS288-Mstn complex. At acidic pH values, binding of heparin to FS288 and the FS288-ActA complex was enhanced. While slightly acidic pH values (pH 6.2 and 5.2) enhanced the binding of the FS288-Mstn complex to heparin, at pH 4 heparin binding was inhibited. Overall, these studies demonstrate that binding of a specific ligand to FS288 differentially regulates its affinity and behavior for heparin molecules.     

Influence of high ambient temperatures on the physiological responses and body sway in healthy young adults after quickly standing

This study was aimed to compare the variations in cerebral oxygenation, blood pressure and center-of-foot pressure after standing from sitting and supine positions at normal (22 degrees C) and high (32 degrees C) room temperatures. Thirty young adults stood up from a resting posture (sitting or supine position) and kept the static standing posture for 90 sec. Meanwhile, their center-of-foot pressure (COP), blood pressure, and cerebral oxygenation kinetics were measured in continuity. The change of the frequency domain low-to-high frequency (LF/HF) ratio of the R-R interval before and after standing from a supine position was significantly higher than that from a sitting position under both temperature conditions. Blood pressure as well as total and oxygenated hemoglobin levels decreased immediately after standing up and the ratio of blood pressure change when moving from a supine position to standing at high room temperature was the largest as compared with the other conditions. Total hemoglobin (Hb) volume was found to temporarily decrease after standing and required 22-24 sec to recover when the subject started from the sitting position and 33-36 sec when the subject started from the supine position. Cerebral oxygenation kinetics tended to be larger under high, rather than normal, temperature conditions. All COP parameters after standing were significantly larger in the high temperature condition than in the normal temperature condition. Body sway after standing was larger in the high temperature condition than in the normal temperature condition and after standing from a supine position than from a sitting position. In conclusion, cerebral oxygenation kinetics and blood pressure measured after the subject moved to the standing position changed dramatically under high temperature conditions, and variations in this parameter may influence body sway.     

Effects of posture on the venodilatory response to nitroglycerin

To determine the effects of posture on the venodilatory response to nitroglycerin (TNG), the change in forearm venous volume after inflation of an upper arm cuff to 30 mmHg above cuff zero (VV[30]) was measured during control conditions and after TNG (0.8 mg spray) in 18 healthy young volunteers in the supine position and the sitting position. VV[30] was 3.24 +/- 0.98 ml/100 ml arm in the supine position and 2.46 +/- 1.32 ml/100 ml arm in the sitting position. TNG increased VV[30] by 0.56 +/- 0.19 ml/100 ml arm in supine subjects, but by only 0.38 +/- 0.17 ml/100 ml arm in sitting subjects (P = 0.013). When limb volume was measured in the forearm and calf without using a cuff to produce venous congestion, the increase in limb volume with TNG was significantly greater in the sitting than in the supine position. Because the fall in both systolic and diastolic pressure and the rise in heart rate were significantly greater after TNG was administered in the sitting position, it is suggested that a greater reflex venoconstriction occurred in this posture, which antagonized the TNG-induced increase in venous distensibility. In the seated position, the effect of gravity more than compensated for the impaired venodilatory response to TNG. These results suggest that TNG causes a greater reduction in venous return to the heart when administered in the sitting position than in the supine position.     

Structural and biophysical coupling of heparin and activin binding to follistatin isoform functions

Follistatin (FS) regulates transforming growth factor-beta superfamily ligands and is necessary for normal embryonic and ovarian follicle development. Follistatin is expressed as two splice variants (FS288 and FS315). Previous studies indicated differences in heparin binding between FS288 and FS315, potentially influencing the physiological functions and locations of these isoforms. We have determined the structure of the FS315-activin A complex and quantitatively compared heparin binding by the two isoforms. The FS315 complex structure shows that both isoforms inhibit activin similarly, but FS315 exhibits movements within follistatin domain 3 (FSD3) apparently linked to binding of the C-terminal extension. Surprisingly, the binding affinities of FS288 and FS315 for heparin are similar at lower ionic strengths with FS315 binding decreasing more sharply as a function of salt concentration. When bound to activin, FS315 binds heparin similarly to the FS288 isoform, consistent with the structure of the complex, in which the acidic residues of the C-terminal extension cannot interact with the heparin-binding site. Activin-induced binding of heparin is unique to the FS315 isoform and may stimulate clearance of FS315 complexes.     

Detrended Fluctuation Analysis and Adaptive Fractal Analysis of Stride Time Data in Parkinson's Disease: Stitching Together Short Gait Trials

Variability indicates motor control disturbances and is suitable to identify gait pathologies. It can be quantified by linear parameters (amplitude estimators) and more sophisticated nonlinear methods (structural information). Detrended Fluctuation Analysis (DFA) is one method to measure structural information, e.g., from stride time series. Recently, an improved method, Adaptive Fractal Analysis (AFA), has been proposed. This method has not been applied to gait data before. Fractal scaling methods (FS) require long stride-to-stride data to obtain valid results. However, in clinical studies, it is not usual to measure a large number of strides (e.g., strides). Amongst others, clinical gait analysis is limited due to short walkways, thus, FS seem to be inapplicable. The purpose of the present study was to evaluate FS under clinical conditions. Stride time data of five self-paced walking trials ( strides each) of subjects with PD and a healthy control group (CG) was measured. To generate longer time series, stride time sequences were stitched together. The coefficient of variation (CV), fractal scaling exponents (DFA) and (AFA) were calculated. Two surrogate tests were performed: A) the whole time series was randomly shuffled; B) the single trials were randomly shuffled separately and afterwards stitched together. CV did not discriminate between PD and CG. However, significant differences between PD and CG were found concerning and . Surrogate version B yielded a higher mean squared error and empirical quantiles than version A. Hence, we conclude that the stitching procedure creates an artificial structure resulting in an overestimation of true . The method of stitching together sections of gait seems to be appropriate in order to distinguish between PD and CG with FS. It provides an approach to integrate FS as standard in clinical gait analysis and to overcome limitations such as short walkways.     

不同体位对肥胖产妇椎间隙定位的影响

目的:探讨体位对肥胖产妇椎间隙定位准确性的影响。方法:选择2018年1月-6月在上海市同仁医院建卡并定期产检且预产期在此期间的209例肥胖产妇,根据不同穿刺体位按随机数字表法将其分为坐位组(n=104)和侧卧位组(n=105),采用超声检测作为金标准进行椎间隙定位,比较不同体位下触诊定位椎间隙的精准性,及肥胖程度与定位准确性的关系。结果:与侧卧位组比较,坐位组L3-4椎间隙定位时间显著缩短,皮肤至腰椎棘突距离、红色(手法定位)与黑色标记(超声定位)距离明显缩小(P0.05)。与侧卧位组比较,坐位组一次穿刺成功率明显升高,穿刺时间明显缩短(P0.05)。随着BMI的增加,椎间隙定位时间显著延长,皮肤至腰椎棘突距离、红色与黑色标记距离、节段误差率明显增加(P0.05)。结论:肥胖产妇椎间隙定位准确性与体位及肥胖程度密切相关,坐位下椎间隙触诊定位的准确性优于侧卧位。