Evaluation of Lower-Limb Kinematics during Timed Up and Go (TUG) Test in Subjects with Locomotive Syndrome (LS) Using Wearable Gait Sensors (H-Gait System).

Few studies have dealt with lower-limb kinematics during the timed up and go (TUG) test in subjects with locomotive syndrome (LS). This study aimed to evaluate the characteristics of lower-limb kinematics during the TUG test in subjects with LS using the wearable sensor-based H-Gait system. A total of 140 participants were divided into the non-LS (n = 28), the LS-stage 1 (n = 78), and LS-stage 2 (n = 34) groups based on the LS risk test. Compared with the non-LS group, the LS-stage 1 and LS-stage 2 groups showed significantly smaller angular velocity of hip and knee extension during the sit-to-stand phase. The LS-stage 2 group showed significantly smaller peak angles of hip extension and flexion during the walking-out phase compared to the non-LS group. These findings indicate that the evaluation of the lower-limb kinematics during the TUG test using the H-Gait system is highly sensitive to detect LS, compared with the evaluation of the lower-limb kinematics when simply walking.

Trunk Muscle Activities during Ergometer Rowing in Rowers with and without Low Back Pain.

This study aimed to determine the differences in trunk muscle activity during rowing at maximal effort between rowers with and without low back pain (LBP). Ten rowers with LBP and 12 rowers without LBP were enrolled in this study. All rowers performed a 500-m trial using a rowing ergometer at maximal effort. The amplitudes of the activities of the thoracic erector spinae (TES), lumbar erector spinae (LES), latissimus dorsi (LD), rectus abdominis (RA), and external oblique (EO) muscles were analyzed using a wireless surface electromyography (EMG) system. EMG data at each stroke were converted into 10-time series data by recording averages at every 10% in the 100% stroke cycle and normalized by maximum voluntary isometric contraction in each muscle. Two-way repeated measures analysis of variance was performed. Significant interactions were found in the activities of the TES and LES (P < 0.001 and P = 0.047, respectively). In the post hoc test, the TES activity in the LBP group was significantly higher than that in the control group at the 10% to 20% and 20% to 30% stroke cycles (P = 0.013 and P = 0.007, respectively). The LES activity in the LBP group was significantly higher than that in the control group at the 0% to 10% stroke cycle (P < 0.001). There was a main group effect on the LD activity, with significantly higher activity in the LBP group than in the control group (P = 0.023). There were no significant interactions or main effects in the EO and RA activities between the groups. The present study showed that rowers with LBP compared with those without LBP exhibited significantly higher TES, LES, and LD muscle activities. This indicates that rowers with LBP exhibit excessive back muscle activity during rowing under maximal effort.

Evaluation of gait characteristics in subjects with locomotive syndrome using wearable gait sensors.

BACKGROUND: Individuals with locomotive syndrome (LS) require nursing care services owing to problems with locomotion and the musculoskeletal system. Individuals with LS generally have a reduced walking speed compared with those without LS. However, differences in lower-limb kinematics and gait between individuals with and without LS are not fully understood. This study aimed to clarify the characteristics of the gait kinematics of individuals with LS using wearable sensors. METHODS: We assessed 125 participants (mean age 73.0 ± 6.7 years) who used a public health promotion facility. Based on the 25-question Geriatric Locomotive Function Scale (GLFS-25), these participants were grouped into the non-LS (GLFS-25 < 7), LS-stage 1 (GLFS-25 7-16), and LS-stage 2 (GLFS-25 ≥ 16) groups (larger GLFS-25 scores indicate worse locomotive ability). Spatiotemporal parameters and lower-limb kinematics during the 10-m walk test were analyzed by the "H-Gait system", which is a motion analysis system that was developed by the authors and is based on seven inertial sensors. The peak joint angles during the stance and swing phases, as well as the gait speed, cadence, and step length were compared among all groups. RESULTS: There were 69 participants in the non-LS group, 33 in the LS-stage 1 group, and 23 in the LS-stage 2 group. Compared with the non-LS group, the LS-stage 2 group showed significantly smaller peak angles of hip extension (9.5 ± 5.3° vs 4.2 ± 8.2°, P = 0.002), hip flexion (34.2 ± 8.8° vs 28.5 ± 9.5°, P = 0.026), and knee flexion (65.2 ± 18.7° vs 50.6 ± 18.5°, P = 0.005). The LS-stage 1 and LS-stage 2 groups had a significantly slower mean gait speed than the non-LS group (non-LS: 1.3 ± 0.2 m/s, LS-stage 1: 1.2 ± 0.2 m/s, LS-stage 2: 1.1 ± 0.2 m/s, P < 0.001). CONCLUSIONS: The LS-stage 2 group showed significantly different lower-limb kinematics compared with the non-LS group, including smaller peak angles of hip extension, hip flexion, and knee flexion. It would be useful to assess and improve these small peak joint angles during gait for individuals classified as LS-stage 2.

Effects of unweighting on gait kinematics during walking on a lower-body positive-pressure treadmill in patients with hip osteoarthritis.

BACKGROUND: Hip osteoarthritis (OA) is a musculoskeletal condition that makes walking difficult due to pain induced by weight-bearing activities. Treadmills that support the body weight (BW) reduce the load on the lower limbs, and those equipped with a lower-body positive-pressure (LBPP) device, developed as a new method for unweighting, significantly reduce pain in patients with knee OA. However, the effects of unweighting on gait kinematics remain unclear in patients with hip OA. Therefore, we investigated the effects of unweighting on kinematics in patients with hip OA during walking on a treadmill equipped with an LBPP device. METHODS: A total of 15 women with hip OA and 15 age-matched female controls wore a three-dimensional (3-D) motion analysis system and walked at a self-selected speed on the LBPP treadmill. Data regarding self-reported hip pain using a numeric rating scale (NRS) in which the scores 0 and 10 represented no pain and the worst pain, respectively, under three different BW conditions (100, 75, and 50%) were collected. Moreover, 3-D peak joint angles during gait under each condition were calculated and compared. RESULTS: In the hip OA group, the NRS pain scores at 50 and 75% BW conditions significantly decreased compared with that at 100% BW condition (50%, P = 0.002; 75%, P = 0.026), and the peak hip extension angle decreased compared with that in the healthy controls (P = 0.044). In both groups, unweighting significantly decreased the peak hip (P < 0.001) and knee (P < 0.001) flexion angles and increased the peak ankle plantar flexion angle (P < 0.001) during walking. CONCLUSIONS: Unweighting by the LBPP treadmill decreased pain in the hip OA group but did not drastically alter the gait kinematics compared with that in the control group. Therefore, regarding the use of the LBPP treadmill for patients with hip OA, clinicians should consider the benefits of pain reduction rather than the kinematic changes.

Analysis of 3-D Kinematics Using H-Gait System during Walking on a Lower Body Positive Pressure Treadmill.

Recently, treadmills equipped with a lower-body positive-pressure (LBPP) device have been developed to provide precise body weight support (BWS) during walking. Since lower limbs are covered in a waist-high chamber of an LBPP treadmill, a conventional motion analysis using an optical method is impossible to evaluate gait kinematics on LBPP. We have developed a wearable-sensor-based three-dimensional motion analysis system, H-Gait. The purpose of the present study was to investigate the effects of BWS by a LBPP treadmill on gait kinematics using an H-Gait system. Twenty-five healthy subjects walked at 2.5 km/h on a LBPP treadmill under the following three conditions: (1) 0%BWS, (2) 25%BWS and (3) 50%BWS conditions. Acceleration and angular velocity from seven wearable sensors were used to analyze lower limb kinematics during walking. BWS significantly decreased peak angles of hip adduction, knee adduction and ankle dorsiflexion. In particular, the peak knee adduction angle at the 50%BWS significantly decreased compared to at the 25%BWS (p = 0.012) or 0%BWS (p < 0.001). The present study showed that H-Gait system can detect the changes in gait kinematics in response to BWS by a LBPP treadmill and provided a useful clinical application of the H-Gait system to walking exercises.

Abdominal draw-in maneuver changes neuromuscular responses to sudden release from trunk loading in patients with non-specific chronic low back pain.

BACKGROUND: Abdominal draw-in maneuver (ADIM) has been recommended to achieve appropriate trunk muscle response for patients with non-specific chronic low back pain (CLBP). However, it has remained unclear whether the intervention with ADIM could change the trunk muscle response to sudden release from loading, which is considered to contribute mechanical circumstances to low back pain. The purpose of the present study was to investigate the effects of the intervention with ADIM on electromyography (EMG) activities of trunk muscles following sudden release from loading. METHODS: Seventeen subjects with non-specific CLBP participated. Subjects resisted trunk flexion or extension loading in semi-seated position, and then the loading was suddenly released. EMG recordings of 6 trunk muscles were acquired using a wireless surface EMG system. Onset and offset times were calculated from the EMG data. The intervention with ADIM was provided for 4 weeks. The onset and offset times were compared between pre- and post-intervention with ADIM. RESULTS: At the post-intervention, the onset of trunk flexors following release from trunk flexion loading became significantly earlier than pre-intervention (P = 0.028). The offset of flexors following release from trunk extension loading of post-intervention was significantly earlier than that of pre-intervention (P = 0.001). CONCLUSIONS: We showed that the intervention with ADIM changed the EMG activity of trunk flexors in response to sudden release from loading. These results suggest a possibility that ADIM might be effective to improve the neuromuscular control of trunk flexors for the treatment of young patients with non-specific CLBP.

The onset of deep abdominal muscles activity during tasks with different trunk rotational torques in subjects with non-specific chronic low back pain.

BACKGROUND: Although delayed onset of the deep abdominal muscles activity in subjects with non-specific chronic low back pain (CLBP) has been suggested to be related to trunk rotational torque, no study has examined the onsets associated with non-specific CLBP during a variety of tasks with different trunk rotational torque. The aim of this study is to compare the onsets of deep abdominal muscles activity among tasks with different trunk rotational torques in subjects with and without non-specific CLBP. METHODS: Twelve subjects with non-specific CLBP and 13 control subjects were included. They performed 8 types of upper limb movements. The onsets of muscular activity of bilateral internal oblique-transversus abdominis (IO-TrA) and trunk rotational torque due to the upper limb movements were measured using a surface electromyography and a three-dimensional motion analysis system. RESULTS: In non-specific CLBP group, right IO-TrA activities were significantly delayed during tasks with left trunk rotational torque compared with the control (P < 0.05), while onsets of the left IO-TrA activities were significantly later than those of the control during tasks with right rotational torque of the trunk (P < 0.05). There were no significant differences in onsets of both sides IO-TrA during tasks without trunk rotational torque between non-specific CLBP and control groups (P > 0.05). CONCLUSIONS: The onsets of IO-TrA activities in subjects with non-specific CLBP were delayed during tasks with rotational torque of the trunk in the opposite direction, suggesting a possibility that delayed onset of the deep abdominal muscles during rotational torque of the trunk might be etiology of chronic low back pain.

Fear-Avoidance Beliefs Associated with Non-Specific Chronic Low Back Pain in College Athletes.

Purpose: This study aimed to determine the psychosocial factors associated with non-specific chronic low back pain (NS-CLBP) among college athletes. Material and Methods: A cross-sectional study was performed at one university. A non-anonymous, self-administered online questionnaire was collected from each athlete. Participants with a history of orthopaedic spine disease or surgery were excluded. Online responses from 368 college athletes belonging to 18 clubs were collected, among which 263 were included in the analysis. In the 263 responses, 41 individuals were identified as having NS-CLBP. Multivariate logistic regression analyses were performed to determine factors associated with presence of NS-CLBP. Independent variables included the Fear-Avoidance Beliefs Questionnaire physical activity subscale (FABQ-PA) score, Tampa Scale for Kinesiophobia-11 (TSK-11) score, Roland-Morris Disability Questionnaire (RDQ) score, and body mass index (BMI). Additionally, the Mann-Whitney U-test was utilized to compare FABQ-PA, TSK-11, RDQ scores, and BMI between the NS-CLBP and non-NS-CLBP groups. Results: The FABQ-PA (odd ratio = 1.096, P = 0.003) was significantly associated with NS-CLBP. No significant association was observed between NS-CLBP and TSK-11 (P = 0.776), RDQ (P = 0.074), and BMI (P = 0.296). The scores for FABQ-PA, TSK-11, RDQ, and BMI in the group with NS-CLBP were found to be significantly higher compared to the group without NS-CLBP (P < 0.001, P = 0.034, P < 0.001, and P = 0.022, respectively). Conclusion: The present study revealed a significant relationship between higher FABQ-PA scores and NS-CLBP among college athletes. Conversely, TSK-11 and BMI values showed no significant association with NS-CLBP presence. The findings suggest that addressing fear-avoidance beliefs may be crucial in managing NS-CLBP among college athletes.

Relationship between onset of trunk muscle activities and pelvic kinematics in individuals with and without chronic low back pain.

BACKGROUND: Lumbopelvic movement patterns during prone hip extension has been proposed as a clinical screening method for trunk muscle dysfunction in patients with chronic low back pain (CLBP). However, correlations between trunk muscle onset and pelvic kinematics have not been investigated. OBJECTIVE: To examine the correlation between trunk muscle onset and pelvic kinematics during prone hip extension in participants with CLBP. METHODS: Fifteen patients with CLBP and 15 healthy individuals participated. We evaluated the muscle activities of the lumbar multifidus, the longissimus, and the semitendinosus via electromyogram and the displacement angles of the pelvic tilt, oblique and rotation. RESULTS: The onset of the multifidus at the ipsilateral side of hip extension was significantly delayed in the patients with CLBP compared to the control group (P< 0.001). The onset of the ipsilateral multifidus in the control group was significantly correlated with increased anterior pelvic tilt angle (P= 0.019, r= 0.597), whereas no significant correlation was observed in the CLBP group (P= 0.810, r=-0.068). CONCLUSION: The results suggest that pelvic kinematics during prone hip extension does not predict the delayed trunk muscle onset in patients with CLBP.

Trunk Muscle Activity and Ratio of Local Muscle to Global Muscle Activity during Supine Bridge Exercises under Unstable Conditions in Young Participants with and without Chronic Low Back Pain.

Core exercises on an unstable surface increase trunk muscle activity, especially for local muscle groups. Therefore, there is a possibility that exercises on an unstable surface would be effective in the rehabilitation of non-specific chronic low back pain (NSCLBP). The present study assessed trunk muscle activities during bridge exercise on the floor and two kinds of unstable surfaces, i.e., a balance ball and the BOSU, for individuals with and without NSCLBP. This study enrolled 17 and 18 young participants with and without NSCLBP, respectively. In the balance ball condition, both groups showed a significant increase in erector spinae activity compared to the floor condition, and the increase in activity was significantly greater in the NSCLBP group than in the control group (p = 0.038). On the other hand, neither group showed significant changes in trunk muscle activities in the BOSU condition compared to those in the floor condition. The control group showed a significant increase in internal oblique/transversus abdominis activity under the balance ball condition (p = 0.020), whereas there were no significant changes in these muscle activities between the balance ball and floor conditions in the NSCLBP group. The present study showed that participants with NSCLBP significantly increased muscle activity of the erector spinae, one of the global back muscles, on the balance ball in spite of small effects on muscle activity of the internal oblique/transversus abdominis, which is one of the local abdominal muscles. Therefore, attention should be paid to the application of bridge exercises on the balance ball for individuals with NSCLBP.

Effects of Posterior Spinal Correction and Fusion on Postural Stability in Patients with Adolescent Idiopathic Scoliosis.

The present study aimed to assess the effects of posterior spinal correction and fusion on postural stability in patients with adolescent idiopathic scoliosis (AIS). The study included 41 female patients with AIS at our institution. All patients performed three 10 s single-leg standing trials on a force plate. The center of pressure (COP) was measured preoperatively, and at 1 week and 6 months postoperatively. The postural stability parameters were absolute minimum time-to-boundary (TTB), mean of the minimum TTB, mean COP velocity, standard deviation, range, and 95% confidence ellipse area. One-way repeated analysis of variance or Friedman test was applied to the postural stability parameters. Multiple comparisons were performed using the Bonferroni correction. The absolute minimum TTB and the mean minimum TTB showed a significant increase 6 months post-operation as compared to preoperatively and 1 week postoperatively. The COP velocity significantly decreased at 6 months post-operation compared to preoperatively and 1 week postoperatively. These changes in postural stability indicate that spinal correction and fusion can be considered to improve postural stability during single-leg standing tests in the postoperative period.

Prevalence and characteristics of chronic ankle instability and copers identified by the criteria for research and clinical practice in collegiate athletes.

OBJECTIVES: To investigate the prevalence and characteristics of chronic ankle instability (CAI) and copers among collegiate athletes as identified by criteria for research (CAI-R and copers-R) and for clinical practice (CAI-C and copers-C). DESIGN: Cross-sectional study. SETTING: University. PARTICIPANTS: Collegiate athletes (n = 507). MAIN OUTCOME MEASURES: Participants were assessed by questionnaires based on the International Ankle Consortium guidelines. The percentages of participants with CAI-R, CAI-C, copers-R and copers-C were calculated, respectively. Demographic and injury data were statistically compared between CAI-R and copers-R groups. RESULTS: The data of 470 participants was retained after exclusions. Of these, the prevalence of CAI-R (10.0%) was only half of that of CAI-C (19.8%), and that of copers-R and copers-C was about 5%. Seventy percent of unclassifiable participants had recurrent ankle sprains. CAI was most common in basketball, while copers were less prevalent in basketball, judo, rugby and gymnastics. The age at the initial injury was significantly younger in the CAI-R participants than in the copers-R. CONCLUSIONS: The type of sport and the age at the initial injury may be associated with developing CAI. The standard criteria may not capture the entire clinical CAI population, therefore, care should be taken when applying the research to clinical practice.