Hypertension and Stroke Cardiovascular Control Evaluation by Analyzing Blood Pressure, Cerebral Blood Flow, Blood Vessel Resistance and Baroreflex.

Cardiovascular diseases have been the leading causes of mortality in Taiwan and the world at large for decades. The composition of cardiovascular and cerebrovascular systems is quite complicated. Therefore, it is difficult to detect or trace the related signs of cardiovascular and cerebrovascular diseases. The characteristics and changes in cardiopulmonary system disease can be used to track cardiovascular and cerebrovascular disease prevention and diagnosis. This can effectively reduce the occurrence of cardiovascular and cerebrovascular diseases. This study analyzes the variability in blood pressure, cerebral blood flow velocity and the interaction characteristics using linear and nonlinear approaches in stroke, hypertension and healthy groups to identify the differences in cardiovascular control in these groups. The results showed that the blood pressure and cerebral blood flow of stroke patients and hypertensive patients were significantly higher than those of healthy people (statistical differences (p < 0.05). The cerebrovascular resistance (CVR) shows that the CVR of hypertensive patients is higher than that of healthy people and stroke patients (p < 0.1), indicating that the cerebral vascular resistance of hypertensive patients is slightly higher. From the patient's blood flow and vascular characteristics, it can be observed that the cardiovascular system is different from those in healthy people. Baroreflex sensitivity (BRS) decreased in stroke patients (p < 0.05). Chaotic analysis revealed that the blood pressure disturbance in hypertensive patients has a higher chaotic behavior change and the difference in initial state sensitivity. Cross-correlation (CCF) analysis shows that as the course of healthy→hypertension→stroke progresses, the maximum CCF value decreases significantly (p < 0.05). That means that blood pressure and cerebral blood flow are gradually not well controlled by the self-regulation mechanism. In conclusion, cardiovascular control performance in hypertensive and stroke patients displays greater variation. This can be observed by the bio-signal analysis. This analysis could identify a measure for detecting and preventing the risk for hypertension and stroke in clinical practice. This is a pilot study to analyze cardiovascular control variation in healthy, hypertensive and stroke groups.

Echotexture Analysis of L4 Supraspinous Enthesis in Ankylosing Spondylitis.

BACKGROUND: Enthesopathy is a main characteristic of ankylosing spondylitis (AS). However, ultrasonographic features of supraspinous enthesis in AS have not yet been reported. METHODS: Forty-seven AS patients and 22 healthy individuals were enrolled and completed the study. L4 supraspinous entheses were assessed through an ultrasound (US) unit with the participants in a lateral decubitus position. Entheseal echogenicity was interpreted upon inspection of the US image. An entheseal grayscale (GS) value determination, along with an echotexture analysis using a gray-level co-occurrence matrix algorithm, was performed. The thoracolumbar fascia just above the enthesis was also analyzed. An enthesis-to-fascia ratio (EFR) of each texture feature was used for the purpose of intergroup comparison. RESULTS: The prevalence of abnormal entheseal echogenicity in the AS and healthy groups was 19.1% and 13.6%, respectively (P = 0.42). The AS group experienced a higher GS EFR (0.56 [0.10-1.08] vs. 0.40 [0.12-0.89], P = 0.007), higher contrast EFR (0.62 [0.15-1.23] vs. 0.49 [0.23-1.33], P = 0.049), higher variance EFR (0.44 [0.06-1.21] vs. 0.35 [0.13-1.10], P = 0.023), and lower homogeneity EFR (1.07 [0.97-1.27] vs. 1.11 [1.04-1.19], P = 0.011) in comparison to the healthy group. CONCLUSION: Echotexture analysis identified the subtle structural changes in L4 supraspinous enthesis in AS patients. It proved to be superior to the inspection method and may possess the potential for providing early detection of supraspinous enthesopathy in AS.

The effect of weather, air pollution and seasonality on the number of patient visits for epileptic seizures: A population-based time-series study.

OBJECTIVE: The objective of the study was to explore the influences of seasonality, meteorological conditions, and air pollution exposure on the number of patients who visit the hospital due to seizures. METHODS: Outpatient and inpatient data from the National Health Insurance Database of Taiwan from 2009 to 2013, meteorological data from the Meteorological Bureau, and air pollution exposure data from the Taiwan Air Quality Monitoring Stations were collected and integrated into daily time series data. The following data processing and analysis results are based on the mean of the 7 days' lag data of the 18 meteorological condition/air pollution exploratory factors to identify the critical meteorological conditions and air pollution exposure factors by executing univariate analysis. The average hospital visits for seizure per day by month were used as an index of observation. The effect of seasonality has also been examined. RESULTS: The average visits per day by month had a significant association with 10 variables. Overall, the number of visits due to these factors has been estimated to be 71.529 (13.7%). The most obvious factors affecting the estimated number of visits include ambient temperature, CH4, and NO. Six air pollutants, namely CH4, NO, CO, NO2, PM2.5, and NMHC had a significantly positive correlation with hospital visits due to seizures. Moreover, the average daily number of hospital visits was significantly high in January and February (winter season in Taiwan) than in other months (R2 = 0.422). CONCLUSION: The prediction model obtained in this study indicates the necessity of rigorous monitoring and early warning of these air pollutants and climate changes by governments. Additionally, the study provided a firm basis for establishing prediction models to be used by other countries or for other diseases.

Center of Pressure Trace and Sensory Components of the Limits of Stability Test in Older Adults With Vertebral Compression Fractures.

BACKGROUND AND PURPOSE: Patients with vertebral compression fracture (VCF) usually exhibit impaired postural control and consequently are at an increased risk of falling. This study aimed to assess the sensory and kinematic components of the limits of stability (LOS) test in patients with VCF. METHODS: This study enrolled 13 adults with VCF (VCF group), 13 older adults without spinal deformity (NE group), and 13 young adults (NY group). The Biodex balance system was employed to calculate the balance score and the LOS of participants. An inertia motion system was used to record kinematic data. The center of pressure signals of postural stability and LOS were used to calculate the frequency power spectrum for interpreting the sensory component. RESULTS: Compared with the NY group, the VCF group exhibited a longer reaction time and lower balance scores and used a higher median frequency in the medial-lateral and anterior-posterior direction of body acceleration to perform the LOS test. The required ranges of hip rotation and pelvic pitch were significantly higher in the older adult group than in the NY group. In the postural stability test, the VCF group exhibited significantly higher frequency power in the 0.01- to 0.5-Hz band (visual and vestibular) under both the eyes-closed and eyes-open conditions than the other groups. In the LOS test, the VCF group also exhibited lower sensory component activity than the other groups, particularly in vestibular function (0.1-0.5 Hz). CONCLUSIONS: Both musculoskeletal degeneration and sensory integration impairment may contribute to poor direction control and a longer reaction time in patients with VCF.

Evaluating the Far-Infrared Radiation Bioeffects on Micro Vascular Dysfunction, Nervous System, and Plantar Pressure in Diabetes Mellitus.

The most frequent clinical complication is diabetes. Diabetes is characterized by elevated blood glucose levels resulting in sensory nerve damage or lesions. Diabetic foot wounds are often slow to heal and require medical attention and monitoring. This study evaluates the effect of far-infrared radiation on the microcirculation and plantar pressure in the diabetic foot. Ten diabetics and 4 nondiabetics were recruited in this study. The diabetic group was examined before and after the intervention in each month for 3 consecutive months. Four nondiabetic groups were also measured before and after the intervention for 2 weeks in each month. The surface temperature and blood flow in the diabetic foot was significantly improved (temperature: 32.1 ± 2.3°C vs 33.5 ± 2.2°C, P < .05; blood flow image: 118.3 ± 58.1 PU [perfusion unit] vs 50.4 ± 4.3 PU, P < .05). The sympathetic nerve activity index LF also increased from 40.8 ± 18.6% to 61.8 ± 13.5% (P = .07) in the second month. Plantar pressure tended to increase in the third month. This might indicate that far-infrared radiation could affect the mechanical properties of the plantar foot soft tissue. These results indicated that the effects of far-infrared radiation would improve blood circulation and change the soft tissue properties in the diabetic foot.

Acceleration Pattern and Neuromuscular Response of the Spine and Ankle During the Limits-of-Stability Test.

Kuo, FC. Acceleration pattern and neuromuscular response of the spine and ankle during the limits-of-stability test. J Strength Cond Res 34(3): 857-865, 2020-This study aimed to explore the acceleration amplitude, frequency, and electromyography (EMG) activity at the spine, pelvis, and lower extremities under various platform-stability settings. Thirty two young adults (16 men and 16 women) were recruited from a university in Taiwan. A balance system for limits-of-stability testing was used with 2 platform stability settings (i.e., level 4 and static). An inertial motion system and a telemetry EMG system were used to record kinematic and EMG data. Consequently, compared with the level 4 setting, the static-level setting required greater thoracic lateral flexion, pelvic course, and pelvic pitch; greater acceleration amplitudes of the spine, pelvis, and thigh; and greater acceleration frequencies at the shin and ankle. Participants exhibited a significant increase in knee flexion, ankle abduction, foot acceleration, and activity of the rectus femoris and tibialis anterior muscles when the platform stability was decreased. In addition, higher median frequencies of the spine and pelvis and larger amplitudes of the foot were observed under the level 4 setting. The men exhibited a larger range of motion in lumbar joint and thoracic rotation than did the women. To maintain stability, subjects must readjust their head, spine, and ankle movement amplitudes and frequencies depending on the platform stability. The study findings suggest the use of static platform settings for spine control facilitation and unstable platform settings for proprioception and muscle strengthening of lower extremity.

Structural damage and motion rhythm of the spine and hip during trunk lateral bending in ankylosing spondylitis patients with mild to moderate radiographic signs.

BACKGROUND: Ankylosing spondylitis causes structural damage and motion restriction in spine. The study was designed to assess structural damage and incoordination pattern between the spine and hip during trunk lateral bending in ankylosing spondylitis. METHODS: Twenty-three healthy adults and 39 adults with ankylosing spondylitis were recruited from a tertiary care medical centre. Patients with ankylosing spondylitis were divided into two subgroups: sacroiliitis or lumbar-level syndesmophytes (n = 27) and thoracic or cervical-level syndesmophytes (n = 12). An inertia motion system was used to record three-dimensional kinematic data during trunk lateral bending. FINDINGS: Significant differences were observed in lumbar spine syndesmophyte scores, sacroiliitis severity and Bath Ankylosing Spondylitis Metrology Index between the subgroups. The cervical supraspinous ligaments thickness revealed difference between the ankylosing spondylitis and control group, but the Glasgow Ultrasound Enthesitis Scoring System did not revealed difference. Motion analysis revealed that the ankylosing spondylitis group had a larger hip, cervical rotation and smaller lumbar-hip rhythm than the control group; however, the other motions of the spine and hip were smaller. The sacroiliitis or lumbar-level syndesmophytes group had the largest thoracic rotation among the three groups. INTERPRETATION: The different lumbar-hip rhythm between ankylosing spondylitis patients depends on syndesmophyte formation levels. Cervical rotation, the Schober test, the chest expansion test, and lumbar-hip rhythm can indicate the levels of bone damage in ankylosing spondylitis. Clinical examination of ankylosing spondylitis should include kinematic measures of both the spine and hips in the early disease stage.

Breast tumor classification using different features of quantitative ultrasound parametric images.

RATIONALE AND OBJECTIVES: The ultrasound B-mode-based morphological and texture analysis and Nakagami parametric imaging have been proposed to characterize breast tumors. Since these three feature categories of ultrasonic tissue characterization supply information on different physical characteristics of breast tumors, by combining the above methods is expected to provide more clues for classifying breast tumors. MATERIALS AND METHODS: To verify the validity of the concept, raw data were obtained from 160 clinical cases. Six different types of morphological-feature parameters, four texture features, and the Nakagami parameter of benignancy and malignancy were extracted for evaluation. The Pearson's correlation matrix was used to calculate the correlation between different feature parameters. The fuzzy c-means clustering and stepwise regression techniques were utilized to determine the optimal feature set, respectively. The logistic regression, receiver operating characteristic curve, and support vector machine were used to estimate the diagnostic ability. RESULTS: The best performance was obtained by combining morphological-feature parameter (e.g., standard deviation of the shortest distance), texture feature (e.g., variance), and the Nakagami parameter, with an accuracy of 89.4%, a specificity of 86.3%, a sensitivity of 92.5%, and an area under receiver operating characteristic curve of 0.96. There was no significant difference between using fuzzy c-means clustering, logistic regression, and support vector machine based on the optimal feature set for breast tumors classification. CONCLUSION: Therefore, we verified that different physical ultrasonic features are functionally complementary and thus improve the performance in diagnosing breast tumors. Moreover, the optimal feature set had the maximum discriminating performance should be irrelative to the power of classifiers.

Prolonged length of stay for acute hospital admissions as the increasing of age: A nationwide population study for Taiwan's patients with cerebral palsy.

BACKGROUND: Studies investigating reasons for the admission and the associated lengths of stay (LOSs) among cerebral palsy (CP) patients are limited. This study determined common reasons for acute hospitalizations and the LOSs among children, adolescents, and young adults with CP. METHODS: We performed a secondary analysis of data. CP patients aged 4-32.9 years were identified by CP registry in the catastrophic illness patient registry of the 2010 Taiwan National Health Insurance Research Database. Data of admission claims from 2010 to 2011 were analyzed. Reasons for admissions were identified according to International Classification of Diseases codes. Common reasons, frequencies of admissions for each reason, and LOSs were reported. RESULTS: Pneumonia, other respiratory problems, and epilepsy were the top three reasons for admissions in all groups. Other common reasons in all groups were sepsis, other respiratory infections, and gastrointestinal problems. The reasons specific to children included orthopedic issues; ear, nose, and throat problems; and urinary tract infections (UTIs). In youths, scoliosis, and contractures, were unique reasons. In young adults, UTIs, blood problems, and mental illness, were special reasons. Most admission reasons appeared to prolong LOS, and the LOS exhibited an increasing trend as age increased. CONCLUSION: The results implied that patients with CP are more susceptible to most disease invasions. Our results also suggest that the current care system in Taiwan is unsuitable for patients with CP. These results can be used as guidance for planning effective multidisciplinary assessments in the future.

Prevalence and demographic characteristics of comorbid epilepsy in children and adolescents with cerebral palsy: a nationwide population-based study.

INTRODUCTION: The nationwide prevalence of cerebral palsy (CP) is unknown due to the lack of a population-based registration system for CP in Taiwan. This study was the largest nationwide, population-based, cross-sectional study to estimate the prevalence of CP, prevalence rates of comorbid epilepsy in patients with CP, and association with socioeconomic status (SES) in Taiwan. The crude prevalence rate and age- and gender-specific prevalence rates were estimated. METHODS: A total of 8419 patients with CP were enrolled, and the estimated prevalence of CP was 1.76‰ in the pediatric population and 1.51‰ and 1.98‰ in girls and boys, respectively. The prevalence rate of epilepsy in patients with CP was 29.8%. RESULTS: The result revealed a higher prevalence of CP and epileptic CP in members of families with lower insurance premiums than those with higher insurance premiums and those from East Taiwan compared with those from other areas of Taiwan. Moreover, a higher prevalence of CP is shown in rural area than urban area. DISCUSSION: SES and geographic variables were significantly associated with the risk of epilepsy in children with CP. Patients with epileptic CP had a higher odds ratio of several neuropsychiatric diseases, including mental retardation, ophthalmologic problems, hearing impairment, and hydrocephalus.

Cross-correlation between spine and hip joint kinematics differs in healthy individuals and subgroups of ankylosing spondylitis patients during trunk lateral flexion.

BACKGROUND: The effects of sacroiliitis and syndesmophyte formation on the cross-correlation between spine and hip joint kinematics in ankylosing spondylitis (AS) are poorly understood. OBJECTIVE: To investigate the cross-correlation between spine and hip joint kinematics differs in healthy individuals and ankylosing spondylitis patients during trunk lateral flexion. METHODS: Fifty AS patients and thirty-nine healthy adults (controls) were recruited from a medical center. The patients were divided into two subgroups, namely the sacroiliitis (n = 28) and syndesmophyte (n = 22) subgroups. An inertial motion system was used to record kinematic data of spine, pelvic and hip joints during lateral trunk flexion. The maximal cross-correlation coefficient (CCF) and time lag of motion between the spine and hip joint were analyzed. RESULTS: The syndesmophyte group had the smallest range of motion in all recorded motion. The sacroiliitis group exhibited higher thoracic flexion, pelvic pitch, and pelvic rotation than the other two groups. In the syndesmophyte group, the CCF between lumbar lateral flexion (LLF) and hip abduction were weakly and LLF and hip rotation were strongly correlated. Considering in time sequence, LLF occurred earlier than hip abduction and hip rotation during trunk lateral flexion; however, both AS subgroups exhibited longer time lags than in the control group. CONCLUSION: The cross-correlation between spine and hip joint kinematics differs in healthy individuals and AS patients during trunk lateral flexion. The motion pattern changes in patients with AS of differing severity may also alter the loads on the spine and hip joints.

Association of epilepsy and asthma: a population-based retrospective cohort study.

BACKGROUND: Epidemiologic data supporting the epilepsy-asthma association are insufficient. Therefore, we examined this association in this study. METHODS: By using claims data from the National Health Insurance Research Database (Taiwan), we executed a retrospective cohort analysis. Analysis 1 entailed comparing 150,827 patients diagnosed as having incident asthma during 1996-2013 with disease-free controls who were selected randomly during the same period, frequency matched in terms of age and sex. Similarly, analysis 2 entailed comparing 25,274 patients newly diagnosed as having epilepsy with sex- and age-matched controls who were selected randomly. At the end of 2013, we evaluated in analysis 1 the epilepsy incidence and risk and evaluated in analysis 2 the asthma incidence and risk. We applied Kaplan-Meier analysis to derive plots of the proportion of asthma-free seizures. RESULTS: In analysis 1, the asthma group exhibited a higher epilepsy incidence than did the control group (3.05 versus 2.26 per 1,000 person-years; adjusted hazard ratio: 1.39, 95% CI [1.33-1.45]). We also noted a greater risk of subsequent epilepsy in women and girls. In analysis 2, we determined that the asthma incidence between the control and epilepsy groups did not differ significantly; however, some age subgroups including children and individuals in their 30s had an increased risk. A negative association was found in adolescents. The Kaplan-Meier analysis revealed epilepsy to be positively associated with subsequent onset of asthma within seven years of epilepsy diagnosis. DISCUSSION: Asthma may be associated with high epilepsy risk, and epilepsy may be associated with high asthma risk among children and individuals in their 30s. Nevertheless, people with epilepsy in other age subgroups should be aware of the possibility of developing asthma within seven years of epilepsy diagnosis.

Kinematics and muscle activity of the head, lumbar and knee joints during 180° turning and sitting down task in older adults.

BACKGROUND: The "180° turning and sitting down task" is a very conscious movement that requires focusing on turning at the exact moment, and very few studies address on this topic in older adults. The purpose of the study was to compare kinematics and electromyography of the head, lumbar and knee joints during 180°turning in older and young adults. METHODS: Twenty older adults and 20 younger adults were assessed. A 16-channel telemetry electromyography system with electrogoniometers and an inclinometer were used to record the head, lumbar and knee joint kinematic and electromyography data during the 180° turning. This movement had been further divided into 4 phases (braking, mid-stance, swing, and terminal loading) for analysis. FINDINGS: There were significant differences in the joint displacement and muscular activity among the different phases. Comparison between groups showed that the older adults group had less lateral lumbar flexion, less knee flexion and lower velocity of the head and knee flexion compared to young adults during turning. The electromyography data of the left biceps femoris, left gastrocnemius and left erector spinae muscles in the older adults group showed significantly higher levels than in the young adults. INTERPRETATION: Older adults need to adjust velocities of moving joints and increase the extensor synergy muscles of the back and the stance leg to provide posture stability. Kinematics and neuromuscular modulations of the head, lumbar and knee are required according to the various phases of the turn movements and change with aging.

Kinematic variability of the head, lumbar spine and knee during the "walk and turn to sit down" task in older and young adults.

UNLABELLED: This study investigates the kinematic variability of the head, lumbar spine and knee during the various walk and turn to sit phases in older and young adults. Sixteen older adults and eighteen young adults were recruited for this study. Each subject performed the "Walk and turn to sit down" test. A 16-channel telemetry system with electrogoniometers and an inclinometer was used to record the kinematic data. The turning step was divided into braking, mid-stance, swing and terminal load phases for kinematic analysis. The results showed that the older adults had a lower displacement angle and velocity of the lumbar spine, head and knee during different turning phases than the young adults. However, older adults performed turning with a higher variability in angular velocity of head flexion than the young adults during the turning step. The onset of lumbar movement and lateral flexion of the head occurred significantly earlier in older adults than in the young adults during turning. CONCLUSION: Older adults more cautiously control their motion by changing their trunk movement amplitude, velocity and timing in relation to their lower extremity movements during turning. The larger variability in angular velocity of head flexion may imply that older adults cannot precisely estimate the required movement for smooth turning.

Mechanical pain sensitivity of deep tissues in children--possible development of myofascial trigger points in children.

BACKGROUND: It is still unclear when latent myofascial trigger points (MTrPs) develop during early life. This study is designed to investigate the mechanical pain sensitivity of deep tissues in children in order to see the possible timing of the development of latent MTrPs and attachment trigger points (A-TrPs) in school children. METHODS: Five hundreds and five healthy school children (age 4- 11 years) were investigated. A pressure algometer was used to measure the pressure pain threshold (PPT) at three different sites in the brachioradialis muscle: the lateral epicondyle at elbow (site A, assumed to be the A-TrP site), the mid-point of the muscle belly (site B, assumed to be the MTrP site), and the muscle-tendon junction as a control site (site C). RESULTS: The results showed that, for all children in this study, the mean PPT values was significantly lower (p < 0.05) at the assumed A-TrP site (site A) than at the other two sites, and was significantly lower (p < 0.05) at the assumed MTrP site (site B) than at the control site (site C). These findings are consistent if the data is analyzed for different genders, different dominant sides, and different activity levels. CONCLUSIONS: It is concluded that a child had increased sensitivity at the tendon attachment site and the muscle belly (endplate zone) after age of 4 years. Therefore, it is likely that a child may develop an A-Trp and a latent MTrP at the brachioradialis muscle after the age of 4 years. The changes in sensitivity, or the development for these trigger points, may not be related to the activity level of children aged 7-11 years. Further investigation is still required to identify the exact timing of the initial occurrence of a-Trps and latent MTrPs.

Postural control strategies related to anticipatory perturbation and quick perturbation in adolescent idiopathic scoliosis.

STUDY DESIGN: Cross-sectional study. OBJECTIVE: To investigate the automatic balance correction related to anticipatory perturbation (AP) and quick backward perturbation in adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Most previous studies on AIS patients focused on posture sway and lacked analysis of muscle activated patterns in dynamic standing control. METHODS: Thirty-two AIS patients and 23 age-matched normal subjects received perturbation balance tests on an unstable platform. The tilting angle of the platform and the muscle activity of the bilateral lumbar multifidi, gluteus medii, and gastrocnemii muscles were recorded. Electromyographic (EMG) amplitude, onset latencies, and duration were calculated with software accompanied with machine. RESULTS: The AIS group had less posture tilting but higher muscle activities than normal subjects under both perturbation conditions (P < 0.05). Under the AP test, AIS showed earlier onset and prolonged activation of left multifidus and right gastrocnemius compared with normal subjects (P < 0.05). The latency of the multifidus on the lumbar convex side occurred earlier than on the concave side. However, the asymmetric onset timing of the gastrocnemius was the opposite of the multifidi in the AIS group (P < 0.05). In contrast to the AP condition, bilateral leg and trunk muscles activated at similar latencies and durations in the AIS group (P < 0.05). Under the quick backward perturbation test, the control group had longer active duration of right multifidus and bilateral gastrocnemii than AIS to cope with larger platform tilting. In addition, asymmetric onset of gluteus medii and duration of multifidi was observed in the control group (P < 0.05). CONCLUSION: There were significant differences in posture control patterns between AIS and normal subjects. AIS subjects have asymmetric habitual muscle activities for AP, whereas when coping with sudden balance threats, they react with synchronized recruitment of bilateral postural muscles.

Squat-to-reach task in older and young adults: kinematic and electromyographic analyses.

The purpose of this study was to compare the two-dimensional kinematic and electromyographic (EMG) changes during the squat-to-reach task in older and young adults. Twenty-six older adults and thirty-three young adults were studied. A 16-channel telemetry system was used for recording muscular activity and kinematic data during two trials of a squat-to-reach task. Surface EMG data were recorded on select muscles of the trunk and the lower extremity on the dominant side. An electrogoniometer was fixed over the knee joint, and an inclinometer was fastened on the head and thigh to record kinematic data. The task was split into six movement phases based on the angular displacement and velocities of the knee joint. The mean values of the maximal displacements in the sagittal plane of the head, knee, and thigh were significantly (p<0.05) lower, but those in the frontal plane of the head and thigh were significantly (p<0.05) higher in older adults than in young adults. Thigh muscle activities were significantly (p<0.05) higher in older adults than in young adults throughout the movements. The trunk and leg muscles contracted earlier, but the hip adductors contracted later in older adults compared to young adults (p<0.05). The older adults squatted in a shallow and heel-off posture during forward reaching tasks. Therefore, older adults had increased lateral flexion of the head to compensate for insufficient knee flexion during the squat-to-reach movement and required increased activity of the posture muscles to maintain lateral stability.

Impact of visual and somatosensory deprivation on dynamic balance in adolescent idiopathic scoliosis.

STUDY DESIGN: A cross-sectional study of balance control in adolescents with idiopathic scoliosis (AIS). OBJECTIVE: To investigate the impact of visual and somatosensory deprivation on the dynamic balance in AIS patients and to discuss electromyographic (EMG) and posture sway findings. SUMMARY OF BACKGROUND DATA: Most studies focus on posture sway in quiet standing controls with little effort on examining muscle-activated patterns in dynamic standing controls. METHODS: Twenty-two AIS patients and 22 age-matched normal subjects were studied. To understand how visual and somatosensory information could modulate standing balance, balance tests with the Biodex stability system were performed on a moving platform under 3 conditions: visual feedback provided (VF), eyes closed (EC), and standing on a sponge pad with visual feedback provided (SV). Muscular activities of bilateral lumbar multifidi, gluteus medii, and gastrocnemii muscles were recorded with a telemetry EMG system. RESULTS: AIS patients had normal balance index and amplitude and duration of EMG similar to those of normal subjects in the balance test. However, the onset latency of right gastrocnemius was earlier in AIS patients than in normal subjects. In addition, body-side asymmetry was noted on muscle strength and onset latency in AIS subjects. Under EC condition, lumbar multifidi, and gluteus medii activities were higher than those under SV and VF conditions (P < 0.05). Under SV condition, the medial-lateral tilting angle was less than that under VF and EC conditions. In addition, the active duration of right gluteus medius was shorter under SV condition (P < 0.05). CONCLUSION: The dynamic balance control is particularly disruptive under visual deprivation with increasing lumbar multifidi and gluteus medii activities for compensation. Sponge pad can cause decrease in frontal plane tilting and gluteus medii effort. The asymmetric muscle strength and onset timing are attributed to anatomic deformation as opposed to neurologic etiological factors.

Electrophysiologic effects of a therapeutic laser on myofascial trigger spots of rabbit skeletal muscles.

OBJECTIVE: To better understand the mechanisms of therapeutic lasers for treating human myofascial trigger points, we designed a blinded controlled study of the effects of a therapeutic laser on the prevalence of endplate noise (EPN) recorded from the myofascial trigger spot (MTrS) of rabbit skeletal muscle. DESIGN: In eight rabbits, one MTrS in each biceps femoris muscle was irradiated with a 660-nm, continuous-wave, gallium-aluminum-arsenate (GaAlAs) laser, at 9 J/cm2. The contralateral side of muscle was treated with a sham laser. Each rabbit received six treatments. The immediate and cumulative effects were assessed by the prevalence of EPN with electromyographic (EMG) recordings after the first and last treatments. RESULTS: Compared with pretreatment values, the percentages of EPN prevalence in the experimental side after the first and last treatments were significantly reduced (P < 0.01 for both). The change in EPN prevalence in the experimental side was significantly greater than in the control side immediately after the first and last treatments (P < 0.05). However, no significant differences were noted between the first and last treatments (P > 0.05). CONCLUSIONS: In our study, immediate and cumulative effects of a GaAlAs laser applied on MTrS were demonstrated on the basis of the assessment of EPN prevalence. It seems that laser irradiation may inhibit the irritability of an MTrS in rabbit skeletal muscle. This effect may be a possible mechanism for myofascial pain relief with laser therapy.