Relationship between single-leg stance test with light touch and hip muscle strength in healthy young adults

[Purpose] This study investigated the relationship between the single-leg stance test with light touch and hip rotator muscle strength. [Participants and Methods] Thirty-one healthy young adults participated in the study. A single leg stance test with light touch was performed to evaluate the participants’ static balance ability. The duration that an individual could successfully perform the single leg stance test with light touch in the eyes open was measured. The participants were instructed to slightly touch their right index fingertip on the digital scale. The hip muscle strength of the internal rotators and external rotators were measured by the isometric peak torque. The internal/external rotator strength ratio was calculated by dividing the strength of the internal rotator by that of the external rotator. [Results] The hip external rotator muscle strength was higher in males than in females. Moreover, there was a significant correlation between the single-leg stance test with light touch and hip external rotator muscle strength in males and between the single leg stance test with light touch and hip internal rotator muscle strength in females. Furthermore, a significant positive correlation was found between the single leg stance test with light touch and hip internal rotator/external rotator ratio in males. [Conclusion] We concluded that the single leg stance test with light touch is a useful tool to evaluate static hip muscle strength.Key words: Hip rotator cuff, Hip stability, LT-SLST     

Differences in the total hip rotation range of motion between sides in healthy young Japanese adults

[Purpose] To investigate the difference by degrees in total hip rotation range of motion (ROM) between sides and with regard to gender in healthy young Japanese adults. [Participants and Methods] Data from previously published studies were used. We utilized the left and right hip rotation ROM of 205 Japanese participants aged 18 to 25 years, who satisfied the inclusion criteria and were randomly measured three times in the prone position by the double-blind method. The average value of the three measurements was used to calculate the left–right difference of the hip total rotation ROM in the hip joints, which is the sum of the hip internal and external rotation ROM. We investigated the distribution of the total hip rotation considering the flexibility factor and its relationship with gender. [Results] We confirmed that there were seven participants with 2 SD or more and two with 3 SD or more. No significant difference was found in the left–right difference in the total hip rotation ROM, regardless of gender. [Conclusion] The distribution of left–right differences in the total hip rotation ROM in healthy young adults showed the existence of a significant left–right difference of 2 SD or more.Key words: Total hip rotation, Range of motion, Laterality     

Relationship between muscle echo intensity on ultrasound and isokinetic strength of the three superficial quadriceps femoris muscles in healthy young adults

[Purpose] The purpose of this study was to clarify the relationship between muscle echo intensity measured with ultrasound and the isokinetic strength of each of the three superficial quadriceps femoris muscles in healthy young adults. [Participants and Methods] We measured the echo intensity of the three superficial muscles of the quadriceps femoris in 25 healthy adults (10 males and 15 females; mean age, 22.3 years) using ultrasound. Moreover, we obtained the maximum force during isokinetic knee extension at 60°/s using an isokinetic dynamometer. [Results] In males and females, a significant negative correlation between echo intensity and muscle strength was found in the VM (r=−0.65 and r=−0.63, respectively). [Conclusion] In both males and females, only the muscle echo intensity of the vastus medialis was found to have a negative correlation with the maximum force during isokinetic knee extension at 60°/s. Our data lay the foundation for simplifying and rationally performing the measurement of muscle echo intensity of the quadriceps femoris. And it would therefore be sufficient to only measure the VM to clarify a relationship between EI and maximum isokinetic force in the quadriceps.Key words: Echo intensity, Isokinetic strength, Quadriceps femoris muscle     

成年人身高与去脂组织重的关系

目的研究成年人去脂组织重(fat-free mass,FFM)与身高之间的关系,并建立预测FFM的简单方程.方法对955名健康成年人进行人体测量和生物电阻抗测量,按BMI分为肥胖组和非肥胖组,按年龄分别45岁以下组和45岁以上组,分析FFM与年龄和肥胖的关系.根据FFM是身高的异速生长指数的模型关系,进行非线性回归,建立指数曲线回归方程.结果18～45岁健康成年人的身高为(1.65±0.07)m,体质量为(62.03±10.69)kg,体脂质量(11.28±6.75)kg,体脂含量(17.91±8.67)%,去脂组织含量(82.02±8.87)%,BMI(22.85±2.99)kg/m2,而46～74岁健康成年人的相应指标为(1.62±0.08)m,体质量为(66.08±10.21)kg,体脂质量(14.56±6.44)kg,体脂含量(22.09±9.23)%,去脂组织含量(77.58±10.07)%,BMI(25.19±2.95)kg/m2,差异有显著性意义(P＜0.05);18～45岁与46～74岁的健康人的FFM分别为(50.93±10.23),(51.53±10.07)kg,差异无显著性意义(P＞0.05);健康成年人的FFM并不随年龄增加;非肥胖组与肥胖组的FFM也是相对不变的.预测男性FFM的适宜方程为FFM(kg)=24.98×身高1.68,预测女性FFM的适宜方程为FFM(kg)=22.84×身高1.42.结论以身高为变量能估计出正常成年人FFM的近似值.     

Knee joint angle sensing in healthy young adults using flexible orthosis with different wearing pressure

[Purpose] To investigate the effects of a flexible brace, by analyzing whether its usage; the difference in wearing pressure could change the joint position sensation in healthy participants; and develop a flexible knee brace for patients with knee osteoarthritis. [Participants and Methods] The study included eight healthy males with 14 knee joints (mean age, 22.0 ± 3.1 years). To measure joint position sense, an “angle reproduction test” was performed in three experimental conditions: 1) participants not wearing the brace, 2) the brace was secured with an appropriate force, and 3) the brace was fully secured using hook-and-loop fasteners. [Results] No significant difference was observed among groups comprising of those not wearing, those wearing with the standard force, and those wearing with the tight force. When the maximum hook-and-loop fastener was squeezed, the sensory error in joint position was maximized at both 30° and 60° flexion. [Conclusion] Joint position sense improvement was confirmed to be poor by orthosis, and an error occurred in the joint position sense by increasing the wearing pressure in orthosis. In future, measurements should be performed on patients with knee osteoarthritis who have decreased joint position sense and verify the effect of different wearing pressures verified.     

Ranges of active joint motion for the shoulder,elbow, and wrist in healthy adults

Purpose: The aim of this study was to show highly reliable normal values and three-dimensional characteristics for final range of motion during active movements of the upper extremity joints, and to develop a database from healthy participants, with the advantage of this database lying in the methods of defining shoulder axial rotation angle and of compensating for soft tissue artifacts. Methods: We used an electromagnetic tracking system (FASTRAK) to measure three-dimensional motions of the shoulder (thoracohumeral), elbow/forearm, and wrist in 20 healthy adults (age range: 18–34 years) during active joint motion tasks of the upper extremity. Results: Joint angles of the upper extremity at the final position of joint motion tasks were determined. Highly reliable data for shoulder axial rotation angle were obtained, using a new definition of joint angle and regression analysis to compensate for estimation errors. Conclusions: These results should be useful in setting goals for the treatment of upper extremity joint functions in the fields of rehabilitation, orthopedics, and sports medicine.

Implications for Rehabilitation

• Complex joint motions that occur naturally (unconsciously) about some axes should be taken into account in interventions for range of joint motion (ROM).

• The data obtained through this study simultaneously indicating multiple interrelated angles can be used as reference values for maximum active ROM.

• ROM in the directions of motion involved in the various tasks (for example, elevation angle during shoulder flexion) may have a role to play in evaluating and setting goals for patients with impaired ROM of the arm joints.

     

Relationship between visuo-perceptual function and manual dexterity in community-dwelling older adults

[Purpose] The purpose of the present study was to examine the relationship between visual perceptual function and manual dexterity in community-dwelling older adults. [Subjects and Methods] Fifty-eight participants were recruited by convenience sampling from local rehabilitation centers. This was a cross-sectional study that used the following four clinical tools: the Mini-Mental State Examination, 9 Hole Pegboard, Box and Block Test, and Motor-free Visual Perception Test, Third Edition. [Results] The Motor-free Visual Perception Test, Third Edition and Mini-Mental State Examination correlated significantly and positively with Box and Block Test, and did correlate significantly and negatively with 9 Hole Pegboard. [Conclusion] The results of this study suggest that visual perceptual impairment and cognitive dysfunction may influence manual dexterity in older adults, and rehabilitation of upper extremity function, along with visual perception and cognitive training, may be beneficial for this population.Key words: Older adults, Dexterity, Visual perception     

Effects of joint position on the distraction distance during grade III glenohumeral joint distraction in healthy individuals

[Purpose] The study investigated the effects of joint position on the distraction distance during Grade III glenohumeral joint distraction in healthy individuals. [Subjects and Methods] Twenty adults in their forties without shoulder disease were randomly divided into neutral position group (NPG; n = 7), resting position group (RPG; n = 7), and end range position group (ERPG; n = 6). After Kaltenborn Grade III distraction for 40s, the distance between glenoid fossa and humeral head was measured by ultrasound. [Results] The average distances between the humeral head and glenoid fossa before distraction were 2.86 ± 0.81, 3.21 ± 0.47, and 3.55 ± 0.59 mm for the NP, RP, and ERP groups. The distances after applying distraction were 3.12 ± 0.51, 3.86 ± 0.55, and 4.35 ± 0.32 mm. Between-group comparison after applying distraction revealed no significant differences between the NP and RP groups, while there was a statistically significant difference between the NP and RP groups, as well as between the NP and ERP groups. [Conclusion] Joint space was largest in ERP individuals when performing manual distraction.Key words: Joint position, Manual distraction, Glenohumeral joint     

年龄对正常成年人左室各节段心肌运动速度的影响

目的观察正常成年人左室各节段心肌运动速度随年龄变化的规律,为定量评价左室局部功能奠定基础.方法应用心肌组织速度成像技术(TVI)观察108例不同年龄组正常成年人左室各节段心肌收缩期、舒张早期和心房收缩期速度峰值(Vs、Ve、Va)和Ve/Va,分析其随年龄增加的变化规律.结果 Vs在各年龄组之间差异无显著性意义;Ve在40岁以上年龄组显著低于低龄组,而Va在40～49岁组显著高于低龄组,Ve/Va随年龄增长呈逐渐减低趋势,尤其是40～49岁组和360岁组均显著低于低龄组.结论年龄对左室各节段心肌舒张期速度影响显著.     

Relationships between joint motion and facet joint capsule strain during cat and human lumbar spinal motions

Objective

The lumbar facet joint capsule (FJC) is innervated with mechanically sensitive neurons and is thought to contribute to proprioception and pain. Biomechanical investigations of the FJC have commonly used human cadaveric spines, whereas combined biomechanical and neurophysiological studies have typically used nonhuman animal models. The purpose of this study was to develop mathematical relationships describing vertebral kinematics and FJC strain in cat and human lumbar spine specimens during physiological spinal motions to facilitate future efforts at understanding the mechanosensory role of the FJC.

Methods

Cat lumbar spine specimens were tested during extension, flexion, and lateral bending. Joint kinematics and FJC principal strain were measured optically. Facet joint capsule strain–intervertebral angle (IVA) regression relationships were established for the 3 most caudal lumbar joints using cat (current study) and human (prior study) data. The FJC strain–IVA relationships were used to estimate cat and human spine kinematics that corresponded to published sensory neuron response thresholds (5% and 10% strain) for low-threshold mechanoreceptors.

Results

Significant linear relationships between IVA and strain were observed for both human and cat during motions that produced tension in the FJCs (P < .01). During motions that produced tension in the FJCs, the models predicted that FJC strain magnitudes corresponding to published sensory neuron response thresholds would be produced by IVA magnitudes within the physiological range of lumbar motion.

Conclusions

Data from the current study support the proprioceptive role of lumbar spine FJC and low-threshold mechanoreceptive afferents and can be used in interpreting combined neurophysiological and biomechanical studies of cat lumbar spines.     

The relationship between energy cost and the center of gravity trajectory during sit-to-stand motion

[Purpose] The purpose of this study was to examine the relationship between jerk cost and the formation of the center of gravity trajectory during sit-to-stand motion with asymmetrical foot placement. [Subjects] Nineteen male volunteers were included (age: 21 ± 1 years). [Methods] The subjects moved from a sitting position to a standing position under two different foot placement conditions: (1) 0 degrees of dorsiflexion on the non-dominant side and 20 degrees of dorsiflexion on the dominant side (P1) and (2) 20 degrees of plantarflexion on the non-dominant side and 20 degrees of dorsiflexion on the dominant side (P2). Two standing conditions were used: (1) natural movement and (2) instructed movement, with instructions to increase weight bearing on the non-dominant side. The center of gravity trajectory and its jerk cost were calculated at each axis: front and back (jerk-x), right and left (jerk-y), and vertical (jerk-z). [Results] Jerk-x and jerk-y were significantly larger during instructed movement than natural movement in both P1 and P2. Jerk-z was not significantly different between instructed and natural movement in P1 or P2. [Conclusion] These results indicate that energy cost influences the formation of the center of gravity trajectory during sit-to-stand motion with asymmetrical foot placement.Key words: Sit-to-stand, Jerk cost, Asymmetrical foot placement     

Breathing exercises: influence on breathing patterns and thoracoabdominal motion in healthy subjects

BACKGROUND:

The mechanisms underlying breathing exercises have not been fully elucidated.

OBJECTIVES:

To evaluate the impact of four on breathing exercises (diaphragmatic breathing, inspiratory sighs, sustained maximal inspiration and intercostal exercise) the on breathing pattern and thoracoabdominal motion in healthy subjects.

METHOD:

Fifteen subjects of both sexes, aged 23±1.5 years old and with normal pulmonary function tests, participated in the study. The subjects were evaluated using the optoelectronic plethysmography system in a supine position with a trunk inclination of 45° during quiet breathing and the breathing exercises. The order of the breathing exercises was randomized. Statistical analysis was performed by the Friedman test and an ANOVA for repeated measures with one factor (breathing exercises), followed by preplanned contrasts and Bonferroni correction. A p<0.005 value was considered significant.

RESULTS:

All breathing exercises significantly increased the tidal volume of the chest wall (V_cw) and reduced the respiratory rate (RR) in comparison to quiet breathing. The diaphragmatic breathing exercise was responsible for the lowest V_cw, the lowest contribution of the rib cage, and the highest contribution of the abdomen. The sustained maximal inspiration exercise promoted greater reduction in RR compared to the diaphragmatic and intercostal exercises. Inspiratory sighs and intercostal exercises were responsible for the highest values of minute ventilation. Thoracoabdominal asynchrony variables increased significantly during diaphragmatic breathing.

CONCLUSIONS:

The results showed that the breathing exercises investigated in this study produced modifications in the breathing pattern (e.g., increase in tidal volume and decrease in RR) as well as in thoracoabdominal motion (e.g., increase in abdominal contribution during diaphragmatic breathing), among others.     

Relationship between iliopsoas muscle thickness and hip angle during squats in different pelvic positions

[Purpose] This study aimed to investigate the relationships among the changes in iliopsoas muscle thickness, hip angle, and lower limb joint moment during squatting in different pelvic positions to help in performing hip-dominant squatting exercises. [Participants and Methods] The participants were seven healthy adult males. The measurement task consisted of squatting with 60 degrees of knee flexion in three positions: the anterior, neutral, and posterior pelvic tilt positions. The iliopsoas muscle thickness was measured in the center of the inguinal region using ultrasonography. A three-dimensional motion analysis system was used to measure the joint angles and joint moments. [Results] There were no significant differences in pelvic angles between the pelvic positions. The hip angle differences were significantly higher in the anterior and neutral pelvic tilt positions compared to those in the posterior tilt position. Only the anterior pelvic tilt position had a significantly positive correlation with iliopsoas muscle thickness and hip angle differences. [Conclusion] Squatting in the neutral or posterior pelvic tilt position was not associated with hip angle and iliopsoas muscle thickness changes, whereas squatting in an anterior pelvic tilt position was associated with changes in the iliopsoas muscle thickness and hip flexion angle. Our findings suggest that activation of the iliopsoas muscle might be necessary to promote hip-dominant squatting.Key words: Squats, Iliopsoas muscle, Pelvic position     

Relationship between physical factors and tibial motion in healthy subjects: 2D and 3D analyses

This study was undertaken to determine the relationship between physical factors and vertical axial rotation through the tibial shaft caused by passive knee and subtalar joint rotation in healthy subjects. The data collected were analyzed in detail to determine the relationship between various physical parameters, such as age, body mass, height, and sex, and tibial rotation. A total of 484 healthy subjects were examined with the measuring the vertical axial rotation through tibial shaft (MVARTS) system. Evaluators passively measured internal and external tibial rotation. The effects of any 2 simultaneous variables and outcomes with a single variable were analyzed; the results were documented graphically. Data were also examined through multiple regression analysis (stepwise regression). Agreement between right and left internal tibial rotations was observed to be strong, as was agreement between right and left external rotations. Female patients exhibited a greater amount of internal/external rotation than did male patients. Differences between female and male patients were noted to be significant. A highly significant and inverse relationship between physical parameters and tibial rotations was noted. Findings suggest that as age, body mass, and height increase, tibial motion is reduced.     

Hip rotation range of motion in sitting and prone positions in healthy Japanese adults

[Purpose] The aim of this study was to elucidate the difference in hip external and internal rotation ranges of motion (ROM) between the prone and sitting positions. [Subjects] The subjects included 151 students. [Methods] Hip rotational ROM was measured with the subjects in the prone and sitting positions. Two-way repeated measures analysis of variance (ANOVA) was used to analyze ipsilateral hip rotation ROM in the prone and sitting positions in males and females. The total ipsilateral hip rotation ROM was calculated by adding the measured values for external and internal rotations. [Results] Ipsilateral hip rotation ROM revealed significant differences between two positions for both left and right internal and external rotations. Hip rotation ROM was significantly higher in the prone position than in the sitting position. Hip rotation ROM significantly differed between the men and women. Hip external rotation ROM was significantly higher in both positions in men; conversely, hip internal rotation ROM was significantly higher in both positions in women. [Conclusion] Hip rotation ROM significantly differed between the sexes and between the sitting and prone positions. Total ipsilateral hip rotation ROM, total angle of external rotation, and total angle of internal rotation of the left and right hips greatly varied, suggesting that hip joint rotational ROM is widely distributed.Key words: Hip rotation, ROM, Positions     

正常肩锁关节角度与盂肱关节活动的相关性

背景:应用钩钢板固定治疗肩关节损伤或合并锁骨远端骨折时,钩钢板钩部的角度固定不变,而人体肩锁关节正常角度或在上臂运动时会发生相关变化.目的:探讨正常肩锁关节倾斜角度与肩关节活动相关性,及其临床意义.方法:纳入包含肩部CT检查的TOP图像资料97例,其中男57例,女40例,选择CT时TOP图像,在CT上用机器进行角度测量.肩锁关节角度:为肩峰长轴沿线与锁骨远端长轴沿线的夹角,盂肱关节的角度为肱骨外展与垂线的角度.结果及结论:在上肢下垂时平均肩锁角为(162.04±10.53)°.下垂平均肱骨角为(16.06±11.87)°,R=0.010(P＜0.01),说明肩关节与肩锁关节两个角度相关.在上肢上举时肩锁角(174.34±10.14)°,上举肱骨角(137.65±14.48)°,R=0.053(P＜0.01)两个角度也是相关的.提示,肩锁关节角度在肱骨上举运动时发生变化.肩关节活动时肩锁关节相关活动,既盂肱关节活动时,肩锁关节角度也随之变化.     

Relationship between Muscle Fiber Conduction Velocity and the Force-time Curve during Muscle Twitches

[Purpose] The aim of this study was to clarify the relationship between the muscle fiber conduction velocity (MFCV) obtained during muscle twitches from evoked potentials and the dynamic characteristics of muscular tension (muscle dynamic characteristics) by manipulating deep temperature. [Subjects] Subjects were 10 healthy adult men. Their mean age was 23.0 ± 3.9 years. [Methods] Measurement items were MFCV of the right tibialis anterior muscle and the force-time curve of right ankle dorsiflexion (muscle twitch). Measurements were made under conditions of ordinary (room) temperature, hot and cold. The rate of change in maximum torque was calculated from the force-time curve. [Results] In all subjects, MFCV increased significantly with heating and decreased significantly with cooling. A strong correlation was seen between MFCV and deep temperature. A strong correlation was also seen between MFCV and the rate of change in maximum torque. Stronger correlations were seen in the present results than in previous studies that conducted investigations using voluntary contractions. [Conclusion] The present results were not affected by psychological or other such factors, and are valuable as data with high physiological reliability. In conclusion, this study was able to clarify the relationship between MFCV from evoked potentials and muscle dynamic characteristics.Key words: Muscle fiber conduction velocity, Dynamic characteristics of muscular tension, Muscle twitches     

Effect of breathing supplemental oxygen on motion sickness in healthy adults

OBJECTIVE: To compare the effects of breathing supplemental oxygen vs air on alleviating motion sickness in healthy adults. SUBJECTS AND METHODS: Between April and July 2002, 20 healthy subjects were exposed to a provocative motion on 2 occasions (1-week interval) according to a randomized, counterbalanced, crossover design. During motion, subjects rated their nausea (1, no symptoms, to 4, moderate nausea) every 30 seconds. Once mild nausea occurred, subjects began breathing supplemental oxygen or air through a face mask. Motion ceased when moderate nausea occurred, but subjects continued breathing study gases for 5 minutes while recovering. Recovery was assessed for 20 minutes after motion. RESULTS: There were no significant differences in the rate of increase in symptom severity or the rate of recovery between the 2 conditions. CONCLUSION: Breathing supplemental oxygen had no advantage over breathing air in reducing motion sickness in healthy adults.     

Patterns of hip flexion motion predict frontal and transverse plane knee torques during a single-leg land-and-cut maneuver

Background

Impulsive frontal plane knee joint torques directly strain the anterior cruciate ligament and therefore may contribute to injury risk. Because deleterious torques may in part be related to aberrant kinematic movement patterns the primary purpose of this study was to establish a prediction model for frontal plane knee joint torques based on motion characteristics derived from Principal Component Analysis.

Methods

Eighteen healthy NCAA Division I female athletes performed a single-leg land-and-cut maneuver (n = 5 trials) with their dominant limb. Ensemble average lower extremity joint angles for the hip, knee, and ankle along with normalized external knee abduction torques were calculated for the entire stance phase. The ensemble kinematic data were individually submitted to a Principal Component Analysis. Principal component scores were used in a forward step-wise regression model to establish a prediction equation for peak ensemble-averaged knee abduction torque.

Findings

Approximately 31% of the variance in knee abduction torque was explained by a principal component that captured relative magnitudes of hip flexion motion during early stance. Likewise, approximately 32% of the variance in knee internal rotation torque was explained by a principal component that captured overall hip flexion during stance.

Interpretation

Rapid hip flexion motion during the first half of the stance phase of a single-leg land-and-cut maneuver is associated with greater knee abduction joint torques, whereas greater overall flexion during the entire stance phase is associated with smaller internal rotation torques.