Effect of 2 lumbar spine postures on transversus abdominis muscle thickness during a voluntary contraction in people with and without low back pain

Objective

The present study investigated the effect of 2 different lumbar spine postures, neutral and flexed lumbar postures, on transversus abdominis (TrA) muscle function during a voluntary contraction (hollowing and draw-in maneuver) in people with and without low back pain (LBP).

Methods

Thirty participants with LBP and 30 healthy participants were recruited for this cross-sectional study. Transversus abdominis muscle function was measured as a change in thickness with ultrasound imaging. Participants performed voluntary TrA contraction in a supine lying position with the lumbar spine in neutral and flexed postures. Data were analyzed using a 2-way (groups, postures) analysis of variance.

Results

Lumbar posture influenced TrA function during a voluntary contraction in people with and without LBP. There was a significant main effect of posture (F_1,58 = 16.140, P < .001). Neutral lumbar posture improved participants' ability to recruit TrA in both group (mean difference, 7.5%; 95% confidence interval, 3.8%-11.3%). No significant differences were found between healthy subjects and those with LBP.

Conclusions

The results of the present study showed that, in subjects performing a voluntary TrA contraction, the neutral lumbar posture improves the ability to increase change in TrA thickness. This study found no significant difference in TrA thickness change between healthy subjects and those with nonspecific LBP.     

慢性腰背痛及体位对老年患者肺功能的影响

目的:探讨慢性腰背痛及体位对老年患者肺功能的影响及意义。方法:60岁以上老年患者87例,其中骨折性(椎体压缩)慢性腰背痛患者28例,非骨折性慢性腰背痛患者34例和非腰背痛患者25例。骨折组采用坐位、侧卧位、俯卧位,其他组取坐位,分别测量肺活量和第1秒时间肺活量(forcedexpiratoryvolumein1s,FEV1),进行校正处理。结果:老年骨折性慢性腰背痛患者肺活量和FEV1占正常值的百分数值明显低于非骨折慢性腰背痛组,也明显低于非腰背痛组。非骨折性腰背痛组的肺活量和FEV1均低于非腰背痛组。骨折组内俯卧位组的肺活量和FEV1明显低于坐位组及侧卧位组。结论:慢性腰背痛可降低老年患者肺功能,脊柱骨折时尤其明显;俯卧位不利于椎体压缩骨折患者的肺功能恢复。     

Exposure to movement in chronic back pain: evidence of successful generalization across a reaching task

According to the fear-avoidance model, kinesiophobia (pain-related fear) is an important factor in the development of chronic pain and disability through the maintenance of maladaptive avoidance behaviors. Using a paradigm that required repeated exposure to a reaching task, the current study investigated generalization of pain and harm expectancy corrections (i.e., the tendency to bring expectations in line with experience) in chronic low back pain sufferers with high versus low levels of kinesiophobia. Sixty participants were asked to consecutively perform four adaptations of a reaching task, each introducing an element of increased intensity. Expected and experienced pain and harm ratings were collected during the two trials comprising each movement. Individuals with high levels of kinesiophobia reported greater pain and harm ratings during the movements. Further, highly kinesiophobic female, but not male, participants demonstrated greater overprediction of harm relative to low kinesiophobic counterparts during the first reaching trial. Finally, in contrast to previous investigations, highly kinesiophobic participants showed successful generalization of pain expectancy corrections across movement tasks. Possible clinical implications of the findings are noted.     

Effect of a gravity-compensating orthosis on reaching after stroke: evaluation of the Therapy Assistant WREX

Iwamuro BT, Cruz EG, Connelly LL, Fischer HC, Kamper DG. Effect of a gravity-compensating orthosis on reaching after stroke: evaluation of the Therapy Assistant WREX.

Objective

To evaluate the effectiveness of an upper-extremity orthosis to improve the reaching workspace of stroke survivors.

Design

Within-subjects repeated-measures design evaluating reaching with and without the Therapy Assistant Wilmington Robotic Exoskeleton (WREX).

Setting

Laboratory.

Participants

Stroke survivors (N=10) with chronic upper-extremity hemiparesis.

Interventions

Not applicable.

Main Outcome Measures

Arm movement kinematics (Optotrak Certus motion detection system), muscle activity for biceps, triceps, anterior deltoid, and brachioradialis muscles (bipolar surface electromyography).

Results

Significant improvements of reaching distance occurred for all subjects across all targets (P<.001) when using the Therapy Assistant WREX. While the self-selected peak speed of hand movement during the reach decreased significantly with the Therapy Assistant WREX (P<.001), use of the Therapy Assistant WREX led to improved quality of movement as signified by a decrease in jerk (P<.001) and a shift in the timing of the peak speed to an earlier point in the movement (P<.001). Electromyographic muscle activity analysis showed that use of the Therapy Assistant WREX led to a reduction in biceps activity across all targets during the reach (P<.05), in conjunction with a marginally significant reduction in activity of the anterior deltoid (P<.055). No changes were observed in triceps (P=.47) or brachioradialis activity (P=.28).

Conclusions

By reducing requirements for shoulder activation, the Therapy Assistant WREX improved reaching performance among stroke survivors compared with free reaching, thereby potentially facilitating practice of functional tasks.     

Effect of simulated rock climbing finger postures on force sharing among the fingers

OBJECTIVE: To study the forces applied by each finger in different joint postures simulating rock climbing gripping postures. DESIGN: Subjects in sitting posture applied fingertip forces perpendicular to horizontal force sensors in three different finger postures. BACKGROUND: Data provided by the literature indicate that middle and ring finger are commonly injured. However, no quantitative assessment of the forces applied by each finger related to the joint postures has been made. METHODS: Six elite rock climbers performed finger flexion in a single-finger task and a four-finger task. The tests were conducted in an extended posture, a curved posture (the joints belonging to the finger were flexed) and an intermediate posture (the joints were flexed, except the distal one which was fully extended). Each fingertip force was expressed in absolute value and in percentage of the maximal force capacity of the finger. RESULTS: The greater force was applied by the middle finger (20.8 N), whatever the posture. The relative involvement amounted to 105% for the ring finger in the curved posture. CONCLUSIONS: The great force applied by the middle finger and the great relative involvement of the ring finger in the curved posture seem to be the main factors of injuries of these fingers. RELEVANCE: The analysis of force sharing among the fingers during different joint postures mimicking rock climbing is essential to a better understanding of finger injuries.     

神经肌肉本体促通技术对偏瘫患者立位平衡极限的影响

目的观察神经肌肉本体促通技术 (PNF)对偏瘫患者立位平衡极限能力的影响。方法 18例脑卒中恢复期患者分为 :治疗组 (9例 )使用PNF手法 ;对照组 (9例 )采用Bobath、运动再学习等康复技术。均治疗 3个月结果治疗组患者立位平衡极限能力优于对照组 (P <0 0 5 -0 0 1)。结论利用PNF技术对提高偏瘫患者平衡极限能力有明显的效果。     

Inter-observer reproducibility of back surface topography parameters allowing assessment of scoliotic thoracic gibbosity and comparison with two standard postures

The objective of this work was to analyze the inter-observer reproducibility of an upright posture designed to bring out the thoracic humps by folding the upper limbs. The effect of this posture on back surface parameters was also compared with two standard radiological postures. A back surface topography was performed on 46 patients (40 girls and 6 boys) with a minimum of 15° Cobb angle on coronal spinal radiographs. Inter-observer reliability was evaluated using the typical error measurement (TEM) and Intraclass Correlation Coefficient (ICC). Variations between postures were assessed using a Student's t test. The inter-observer reproducibility is good enough for the three postures. The proposed posture leads to significant changes in the sagittal plane as well as in the identification of thoracic humps. This study shows the reproducibility of the proposed posture in order to explore the thoracic humps and highlights its relevance to explore scoliosis with back surface topography systems.     

Individuals with chronic low back pain do not modulate the level of transversus abdominis muscle contraction across different postures

The aim of this study was to evaluate the thickness of the transversus abdominis (TrA) muscle in three basic postures in subjects with and without chronic low back pain. Subjects were classified into a chronic low back pain group (n = 27) and a healthy control group (n = 23). The thickness of the TrA muscle was measured at rest and during the abdominal drawing-in manoeuvre (ADIM) in supine, sitting and standing postures using B-mode ultrasound imaging. Contraction ratio (TrA thickness during the ADIM/TrA thickness at rest) was calculated for each posture. At rest, the TrA thickness in the sitting and standing postures was significantly greater than in the supine posture (p < 0.017) in the control group, but similar in all three postures in the low back pain group. TrA thickness was similar in the low back pain and control group in all three postures. During the ADIM, TrA thickness was significantly greater in the control group than in the chronic low back pain group in all three postures. The contraction ratio was also significantly higher in the control group than in the chronic low back pain group in all three postures. These results indicate that the automatic postural contraction of the TrA observed in the control subjects in the sitting and standing postures was not demonstrated in subjects with chronic low back pain. The present study revealed the one aspect of different response of the TrA muscle to changing posture between two groups.     

Effect of different arm loads on the position of the scapula in abduction postures.

OBJECTIVE: The objective of this study is to determine the relation between arm load and the three-dimensional shoulder orientations. BACKGROUND: Analysis of a musculo-skeletal system by means of an inverse dynamical simulation requires postural data of the bony elements involved. For the shoulder, the positions of the clavicle and the scapula are difficult to record due to the skin displacement. It would therefore be useful to predict the three-dimensional relation between the orientation of the arm, the clavicula and the scapula, i.e. the three-dimensional shoulder rhythm, with respect to the thorax under different load conditions. METHODS: The orientation of the clavicula and the scapula was determined with respect to the thorax by means of palpation of skeletal landmarks, for seven postures of arm elevation in the frontal plane at four load conditions: 0, 0.9, 1.9 and 2.9 kg at the wrist. The data were expressed by Cardan angles and analyzed by means of repeated measurements analysis of variance. RESULTS: While the clavicular and scapular angles were significantly related to the arm elevation, no significant relation was found with the load in the hands for the seven arm postures. CONCLUSIONS: The three-dimensional shoulder rhythm does not change under different gravitational load conditions on the arm. RELEVANCE: The fact that the magnitude of the load does not affect the shoulder postures, i.e. the moment arms of the muscles, facilitates the biomechanical, ergonomical and clinical studies on the shoulder by the reduction on the number of recordings for equal task under different load conditions, and easy imitation of real life tasks in the laboratory.     

不同体位上肢作业治疗对脑梗死偏瘫患者功能活动的影响

目的:观察2种不同体位下的上肢作业治疗对脑梗死偏瘫患者运动功能的影响。方法:选择60例脑梗死后伴有上肢功能障碍的患者,随机分为坐位训练组和站位训练组,每组30例。2组患者在常规康复治疗的基础下,分别给予坐位和站位下的上肢作业治疗。在治疗前、治疗2周、4周后,采用简式Fugl-Myer评分(FMA)、BBS评分及改良Barthel指数(MBI)分别对患者的上肢功能、平衡功能、ADL能力作出评价。结果:治疗2周、4周后,坐位训练组FMA评分与治疗前比较差异无统计学意义(均P0.05),站位训练组FMA评分较治疗前明显增加(P0.05);2个时间点站位训练组评分均高于坐位训练组(均P0.05)。治疗2周、4周后,2组患者BBS评分均较治疗前明显提高(均P0.05),2个时间点站位训练组BBS评分均高于坐位训练组(均P0.05)。治疗2周后坐位治疗组MBI评分与治疗前比较差异无统计学意义(均P0.05),治疗4周后,坐位治疗组MBI较治疗前明显提高(均P0.05);治疗2周、4周后,站位治疗组患者MBI均较治疗前明显提高(均P0.05);治疗2周、4周后,站位训练组MBI评分均明显高于坐位训练组(均P0.05)。结论:站位下的上下肢一体化的作业治疗,加强了全身其他肌肉配合作业活动所必须的稳定和平衡的能力,强化了上肢活动,更容易促进脑梗死偏瘫患者运动功能恢复和生活质量改善。     

Effect of different sitting postures on lung capacity, expiratory flow, and lumbar lordosis

OBJECTIVE: To investigate the effect of sitting posture on lung capacity and expiratory flow (LC-EF) and lumbar lordosis. DESIGN: Repeated measures on 1 group of subjects in 4 postures. SETTING: Laboratory. PARTICIPANTS: Seventy able-bodied volunteers. INTERVENTIONS: Postures were assumed randomly: normal, with full ischial support and flat lumbar support; slumped, with the pelvis positioned in the middle of seat while leaning against the backrest; against the back part of the seat without ischial support (WO-BPS), with partially removed ischial support and an enhanced lumbar support; and standing. MAIN OUTCOME MEASURES: For LC-EF, forced vital capacity, maximum forced expiratory flow, forced expiratory volume in 1 second, and peak expiratory flow; and lumbar lordosis. RESULTS: All LC-EF measures in standing were significantly superior to those in slumped and normal sitting, and 4 measures were significantly higher than in WO-BPS. In slumped sitting, LC-EF significantly decreased from that in normal sitting. WO-BPS sitting significantly increased 4 of the LC-EF measures from those in the normal sitting. Lumbar lordosis was the highest in standing and progressively decreased in WO-BPS, normal, and slumped sitting. CONCLUSIONS: Slumped sitting significantly decreased LC-EF and lumbar lordosis. Because it increases the lumbar lordosis and promotes LC-EF, the WO-BPS posture may be a better seating option for people sitting for a prolonged time.     

Effect of seat cushion on dynamic stability in sitting during a reaching task in wheelchair users with paraplegia

OBJECTIVES: To examine the effects of seat cushions on dynamic stability in sitting during a controlled reaching task by wheelchair users with paraplegia. DESIGN: A randomized, controlled test. SETTING: Rehabilitation center. PARTICIPANTS: Nine wheelchair users with paraplegia. INTERVENTIONS: Three types of cushions--an air flotation, a generic contoured, and a flat polyurethane foam--were tested during a controlled reaching task in ipsilateral and contralateral directions, at 45 degrees from the sagittal plane in the anterolateral direction. Center of pressure (COP) coordinates were monitored by using a pressure measurement system as well as a force platform under seat. MAIN OUTCOME MEASURES: Trajectory of COP, maximal distance covered by COP, maximal velocity of COP; and the index of asymmetry between right and left maximal pressure under ischial tuberosities. RESULTS: The generic contoured cushion allowed the COP to cover significantly (p <.02) a larger distance (81 +/- 28mm) when compared with the air flotation (63 +/- 25mm) or the flat foam (61 +/- 29mm) cushions. The COP velocity was significant (p <.05) for the generic contoured cushion (.14 +/-.05m/s) versus the air flotation (.10 +/-.04m/s) or the flat-foam (.10 +/-.03m/s) cushions. The index of asymmetry was higher for the generic contoured and the flat foam cushions. During reaching, maximal pressure under ipsilateral ischial tuberosity was significantly higher for the flat foam (275 +/- 70mmHg) and the generic contoured (235 +/- 81mmHg) cushions, when compared with the air flotation cushion (143 +/- 51mmHg). CONCLUSION: Seat cushions can significantly affect sitting balance during reaching tasks. This study provided an objective method to assess the dynamic stability of wheelchair users when they perform activities of daily living requiring reaching. These findings have implications for wheelchair seating recommendations, especially seat cushion selection.     

Effect of positioning on back pain after coronary angiography

BACKGROUND: Coronary angiography is a routine cardiac diagnostic procedure in Hong Kong. Patients are restricted to bedrest after the procedure due to potential vascular complications from using a femoral approach. Many patients are required to remain on bedrest for up to 24 hours after the procedure. The effects of reducing this bedrest time is still under investigation. In the meantime, nursing interventions aimed at decreasing patient discomfort due to prolonged bedrest are feasible to implement. AIMS: The aims of this study were to evaluate the severity of back pain related to bedrest duration after coronary angiography and to compare the effects of changing patients' position in bed on their perceptions of back pain and on vascular complications. METHODS: An experimental design was used, with patients randomly assigned either to a control or experimental group. The control group received the usual care, remaining supine and flat for 8-24 hours, with the affected leg straight. The experimental group changed their body position hourly, varying between supine, right side-lying, and left side-lying during the first 7 hours after coronary angiography. RESULTS: A total of 419 patients participated in the study (control, n = 213; experimental, n = 206). Regardless of group assignment, back pain intensity increased with longer time on bedrest. In addition, the control group reported higher levels of pain at all five assessment times. Vascular complications in terms of bleeding at the femoral site were not significantly different between the control and experimental groups. CONCLUSION: The study findings suggest that patients may be able safely to change their position in bed earlier in the post-coronary angiography period than currently recommended in practice protocols. Changing position in bed may also reduce back pain, promote physical comfort, and possibly reduce patients' negative feelings toward coronary angiography.     

Effect of various forearm axially rotated postures on elbow load and elbow flexion angle in one-armed arrest of a forward fall

Background

Falling onto the outstretched hand is a major cause of upper extremity injury. The overall objectives of this study were to develop an experimental model for elbow load during a simulated fall onto one-armed arrest using three different forearm axially rotated postures as alternative fall arrest strategies. Additionally, the relationship between the elbow flexion angle and different axially rotated postures were also investigated.

Methods

Fifteen healthy young male Taiwanese graduate students with an average age of 23 years were studied. Subjects performed a one-armed arrest of a 5 cm fall onto a force plate. Each subject fell onto the force plate with his forearm 45° axial externally rotated (ER), non-rotated (NR), and 45° axial internally rotated (IR) postures. Kinematics and kinetics of the upper extremity were calculated and analyzed by using laboratory-developed motion analysis procedures.

Findings

The valgus–varus shear forces in the ER group were 1.4 times greater than the NR group, and 2.7 times greater than the IR group. The elbow joint remained at almost full extension in the ER (3.9°) group, while elbow flexion angle was observed in the NR (24.6°) and IR (40.3°) groups.

Interpretation

A fall onto the outstretched hand with an externally rotated forearm should be avoided in order to reduce excessive valgus–varus shear force on the elbow joint. Knowledge of elbow kinematics and kinetics during a forward fall with various forearm axially rotated posture may be helpful in preventing injuries.     

自由体位对初产妇产程进展的影响研究

目的探讨自由体位对初产妇产程进展的影响。方法择2013年1月至2014年12月收治的初产妇180例为研究对象,随机将其分为两组,每组各90例。对照组采用传统平卧或侧卧体位待产,观察组采用自由体位待产。观察比较两组产程时间、分娩结局和母婴并发症以及产妇疼痛情况。结果与对照组比较,观察组第一产程、第二产程及总产程时间均明显缩短(P0.05),但第三产程时间两组比较差异无统计学意义。与对照组比较,观察组经阴道分娩的患者比率高,产后出血量明显减少(P0.05),但两者新生儿1 min Apgar评分比较差异无统计学意义。观察组产妇疼痛1级和2级患者所占比率高于对照组,产妇尿潴留发生率和新生儿窒息发生率均明显低于对照组(P0.05)。结论在分娩第一和第二产程中指导初产妇采取自由体位分娩,可缩短产程进展,提高阴道分娩率,降低母婴并发症发生率。