Spinopelvic fusion surgery from lower thoracic spine to pelvis increased hip joint moment-motion analysis.

PURPOSE: Spinal fusion surgery is often performed with pelvic fixation to prevent distal junctional kyphosis. The inclusion of spinopelvic fixation has been reported to induce progression of hip joint arthropathy in a radiographic follow-up study. However, its biomechanical mechanism has not yet been elucidated. This study aimed to compare the changes in hip joint moment before and after spinal fusion surgery. METHODS: This study was an observational study and included nine patients (eight women and one man) who were scheduled to undergo spinopelvic fusion surgery. We calculated the three-dimensional external joint moments of the hip during gait, standing, and climbing stairs before and 1 year after surgery. RESULTS: During gait, the maximum extension moment was 0.51 ± 0.29 and 0.63 ± 0.40 before and after spinopelvic fusion surgery (p = 0.011), and maximum abduction moment was 0.60 ± 0.33 and 0.83 ± 0.34 before and after surgery (p = 0.004), respectively. During standing, maximum extension moment was 0.76 ± 0.32 and 1.04 ± 0.21 before and after spinopelvic fusion surgery (p = 0.0026), and maximum abduction moment was 0.12 ± 0.20 and 0.36 ± 0.22 before and after surgery (p = 0.0005), respectively. During climbing stairs, maximum extension moment was - 0.31 ± 0.30 and - 0.48 ± 0.15 before and after spinopelvic fusion surgery (p = 0.040), and maximum abduction moment was 0.023 ± 0.18 and - 0.02 ± 0.13 before and after surgery (p = 0.038), respectively. CONCLUSION: This study revealed that hip joint flexion-extension and abduction-adduction moments increased after spinopelvic fixation surgery in the postures of standing, walking, and climbing stairs. The mechanism was considered to be adjacent joint disease after spinopelvic fusion surgery including sacroiliac joint fixation.

Effect of Trunk Solution® on hemodynamics in the supplementary motor area during walking.

[Purpose] Humans keep their trunks vertical while walking. This defining characteristic is known as upright bipedalism. Research on the neural control of locomotion indicates that not only subcortical structures, but also the cerebral cortex, especially the supplementary motor area (SMA), is involved in locomotion. A previous study suggested that SMA may contribute to truncal upright posture-control during walking. Trunk Solution® (TS) is a trunk orthosis designed to support the trunk in decreasing the low back load. We hypothesized that the trunk orthosis might reduce the burden of truncal control on the SMA. The objective of this study was, therefore, to determine the effect of trunk orthosis on the SMA during walking. [Participants and Methods] Thirteen healthy participants were enrolled in the study. We measured the hemodynamics of the SMA during walking with functional near-infrared spectroscopy (fNIRS). The participants performed two gait tasks on a treadmill: (A) independent gait (usual gait) and (B) supported gait while wearing the TS. [Results] During (A) independent gait, the hemodynamics of the SMA exhibited no significant changes. During (B) gait with truncal support, the SMA hemodynamics decreased significantly. [Conclusion] TS may reduce the burden of truncal control on the SMA during walking.

Comparison of changes in thigh circumference during the menstrual cycle between female transfemoral amputees and non-amputee females: examination of the reliability and comparison of diurnal and day-to-day fluctuations.

[Purpose] Few studies have investigated diurnal and day-to-day changes in the thigh circumference of the residual limb in female amputees. In this study, we used a limb circumference measuring device to confirm the reliability of the measurement and compared the changes in the measured values over time. [Participants and Methods] The study measured and compared the femoral circumference in 2 female amputees and 8 healthy female non-amputees in the morning and evening. [Results] Reliability was assured by measuring the circumferential diameter in triplicate. There were no significant interactions in both diurnal and day-to-day variations, however, in both variations, there were significant differences in the femoral circumstance at any site among the non-amputees. [Conclusion] The amount of edema increased in the evening and varied from day to day in the non-amputees.

Effect of trim line on stiffness in dorsi- and plantarflexion of posterior leaf spring ankle-foot orthoses.

[Purpose] This study aimed to objectively clarify the effect of the trim line setting on the stiffness of posterior leaf spring ankle-foot orthoses. [Participant and Methods] Posterior leaf spring ankle-foot orthoses were fabricated with two thickness levels and three trim line conditions for the posterior upright width and the dorsi- and plantarflexion moments and stiffness exhibited by the orthoses were measured using an evaluation tester. [Results] The trim line of the posterior upright width affected the dorsiflexion moment generated by the orthoses in plantarflexion. [Conclusion] A strong linear correlation was found between posterior upright width and orthotic stiffness, suggesting that it is highly feasible to standardize orthotic settings according to individual conditions of patients after stroke, even for posterior leaf spring ankle-foot orthoses.

Effects of a wearable device and functional wear on spinal alignment and jump performance.

BACKGROUND/OBJECTIVE: To elucidate the effects of walking exercise using a wearable device and functional wear on spinal alignment and jump performance. METHODS: In total, 27 female college soccer players were randomly divided into two groups: trunk solution (TS) and compression garments (CGs). Spinal alignment, jump performance, and electromyography activity during the jump performance of the two groups were measured after a 20-min walking exercise. The values for each group were compared t pre- and post-intervention. RESULTS: The flexibility of the lower thoracic vertebrae in spinal alignment was increased during extension in the TS group. However, the post-value of the abdominal external oblique muscle during a countermovement jump (CMJ) was significantly lower than its pre-value (p < 0.05). In addition, even though spinal alignment was not affected in the CG group, post-values of the jump height during squat jump and CMJ were significantly higher than their pre-values (p < 0.05). Furthermore, the post-value of the biceps femoris during the countermovement jump with arm was significantly lower than its pre-value (p < 0.05). CONCLUSION: Our study suggested that walking exercise using TS may increase the range of motion of the lower thoracic vertebrae in athletes and reduce the muscular activity of the vastus lateralis during CMJ. Additionally, although spinal aliment is not affected, the jump height may increase using CGs.

A simple method for estimating the intervertebral disc compressive force based on the posture analysis of community-dwelling older adults.

[Purpose] The purpose of this study was to develop a simpler method to estimate the intervertebral disc compressive force in healthy older adults. We also examined the validity of a simpler estimation formula for patients with spinal diseases. [Participants and Methods] Fifty-two older adults participated in the study. The standing posture was measured using a three-dimensional motion capture system. The intervertebral disc compressive force was calculated using a previously reported method. Correlation analysis was used to detect the relationship between the measured parameters and the intervertebral disc compressive force. Multiple regression analysis was performed to obtain an equation for the intervertebral disc compressive force. Correlation analysis was used to determine the regression equation for the patients with spinal diseases. [Results] Multiple regression analysis showed that trunk flexion/extension angle and body mass were significantly associated with intervertebral disc compressive force. A correlation was found between the measured and predicted values in the healthy older adults, whereas both values were inconsistent in patients with spinal diseases. [Conclusion] The results of our study demonstrated that the trunk flexion/extension angle and body mass are indicators of intervertebral disc compressive force and can be used to assess low back mechanical stress in healthy older adults.

The effect of the 'One Stretch' exercise on the improvement of low back pain in Japanese nurses: A large-scale, randomized, controlled trial.

Objectives: To evaluate the 'One Stretch' exercise's effect on improvements in low back pain (LBP), psychological factors, and fear avoidance in a large number of nurses. Methods: Between July 2015 and June 2016, we performed a prospective, randomized, parallel-group, multi-center study with central evaluations. Eligible patients were randomly assigned (1:1:1 ratio) to either the control group (Group A) or an intervention group (Group B: 30-min seminar about the 'One Stretch' exercise, Group C: B + physical and psychological approaches to LBP treatment). The primary outcome was subjective improvement from baseline to 6 months (improved/unchanged/worsened) and overall exercise habits (good/poor). Results: There were 4767 participants: 1799, 1430, and 1548 in Groups A, B, and C, respectively. We collected data on 3439 participants (949, 706, and 751 in Groups A, B, and C, respectively) at the 6-month follow-up. The improvement rates in Groups A, B, and C were 13.3%, 23.5%, and 22.6%, respectively. The worsened pain rates were 13.0%, 9.6%, and 8.1%, which decreased as the intervention degree increased (the Cochran-Armitage trend test: p < .0001). In Groups A, B, and C, 15.6%, 64.9%, 48.8% of the patients, respectively, exhibited exercise habits. Conclusion: The 'One Stretch' exercise is useful for improving LBP.

Disability due to knee pain and somatising tendency in Japanese adults.

BACKGROUND: Knee pain is common and related to knee osteoarthritis. However, there is a discrepancy between knee pain and radiographic osteoarthritis. In the general population, knee pain is associated with psychological and cognitive factors, which would be one explanation for the discrepancy. Limited evidence demonstrates that somatization is associated with knee pain. This study examined the association between disability due to knee pain and a high somatising tendency. METHODS: Japanese adults (aged 20-64 years) who had experienced knee pain in the past four weeks were included in this study (n = 14,695, 50% women). Data were extracted from a large internet survey. Somatising tendency was assessed using the Somatic Symptom Scale-8 (SSS-8). Disability due to knee pain was categorized into three levels: 1) knee pain without difficulty with activities of daily living (ADL), 2) knee pain with ADL difficulty but without requiring sick leave, and 3) knee pain requiring sick leave. The association between ≥ high somatising tendency (SSS-8 score ≥ 12) as well as very high somatising tendency (SSS-8 score ≥ 16) and disability due to knee pain was examined using logistic regression models adjusted for age, sex, body mass index, depressive symptoms, education level, regular exercise, chronicity of knee pain (≥3 months), osteoarthritis, rheumatoid arthritis, and fibromyalgia. RESULTS: Greater disability due to knee pain was associated with a higher odds ratio for ≥ high somatising tendency (adjusted odds ratio (aOR) = 2.36 [2.10-2.66] in group 2 vs. group 1, aOR = 3.23 [2.66-3.92] in group 3 vs. group 1). Stronger associations were found for a very high somatising tendency (aOR = 2.80 [2.42-3.23] in group 2 vs. group 1, aOR = 4.51 [3.64-5.58] in group 3 vs. group 1). CONCLUSIONS: Somatization may play a role in disability due to knee pain in the general adult population with knee pain, similar to the role of somatization in low back pain.

Association of body mass index with chronic pain prevalence: a large population-based cross-sectional study in Japan.

PURPOSE: The aim of this study was to examine the association between body mass index and chronic pain. METHODS: The outcome was chronic pain prevalence by body mass index (BMI). BMIs of less than 18.5, 18.5-25.0, 25.0-30.0, and 30.0 or over kg/m2 were defined as underweight, normal weight, overweight, and obese. SUBJECTS: We used data from 4993 participants (2464 men and 2529 women aged 20-79 years) of the Pain Associated Cross-sectional Epidemiological survey in Japan. Sex-stratified multivariable-adjusted odds ratios were calculated with 95% confidence intervals using a logistic regression model including age, smoking, exercise, sleep time, monthly household expenditure, and presence of severe depression. We analyzed all ages and age subgroups, 20-49 and 50-79 years. RESULTS: The prevalence of chronic pain was higher among underweight, overweight, and obese male respondents than those reporting normal weight, with multivariable odds ratios of 1.52 (1.03-2.25), 1.55 (1.26-1.91), and 1.71 (1.12-2.60). According to underweight, only older men showed higher prevalence of chronic pain than normal weight men with odd ratios, 2.19 (1.14-4.20). Being overweight and obese were also associated with chronic pain in women; multivariable odds ratios were 1.48 (1.14-1.93) and 2.09 (1.20-3.64). Being underweight was not associated with chronic pain. CONCLUSION: There was a U-shaped association between BMI and chronic pain prevalence among men ≥ 50 years, and a dose-response association among women. Our finding suggests that underweight should be considered in older men suffering chronic pain.

Inclination of standing posture due to the presentation of tilted view through an immersive head-mounted display.

[Purpose] The purpose of the present study is to clarify whether tilted scenery presented through an immersive head-mounted display (HMD) causes the inclination of standing posture. [Subjects and Methods] Eleven healthy young adult males who provided informed consent participated in the experiment. An immersive HMD and a stereo camera were employed to develop a visual inclination system. The subjects maintained a standing posture twice for 5s each while wearing the visual inclination system. They performed this task under two conditions: normal view and 20° leftward tilted view. A three-dimensional motion analysis system was used to measure the subjects' postures, and two force plates were used to measure the vertical component of the floor reaction force of each leg. [Results] In the 20° leftward tilted view, the head and trunk angles in the frontal plane were similarly inclined toward the left, and the vertical component of the floor reaction force increased in the left leg, whereas it decreased in the right leg. [Conclusion] When the view in the immersive HMD was tilted, the participants' trunk side bent toward the same side as that of the view. This visual inclination system seems to be a simple intervention for changing standing posture.

Effect of pelvic forward tilt on low back compressive and shear forces during a manual lifting task.

[Purpose] To examine the effect of an instruction to increase pelvic forward tilt on low back load during a manual lifting task in the squat and stoop postures. [Subjects] Ten healthy males who provided informed consent were the subjects. [Methods] Kinetic and kinematic data were captured using a 3-dimensional motion analysis system and force plates. Low back compressive and shear forces were chosen as indicators of low back load. The subjects lifted an object that weighed 11.3 kg, under the following 4 conditions: squat posture, stoop posture, and these lifting postures along with an instruction to increase pelvic forward tilt. [Results] In the squat posture, the instruction to increase pelvic forward tilt reduced the low back compression and shear forces. [Conclusion] The present results suggest that a manual lifting task in the squat posture in combination with an instruction to increase pelvic forward tilt can decrease low back compression and shear forces, and therefore, might be an effective preventive method for low back pain in work settings.

Effect of paralyzed side soleus muscle pressure on the gait of stroke patients as measured by a three-dimensional motion analysis system.

[Purpose] The purpose of this study was to examine the effects of muscle belly compression by a supporter on the paralyzed side soleus muscle of patients with cerebrovascular disability, and to determine the intensity of compression that is effective for improving gait. [Subjects] Eleven patients with chronic cerebral vascular disorder. [Methods] Before setting the supporter, standing posture and 6 m free walking were measured 3 times with the three-dimensional motion analysis system, VICON. Then, supporters were placed on the center of the lower leg of the hemiplegic side of the subjects and inflated to 30 or 50 mmHg. Three minutes after wearing the supporters, the subjects walked again for 3 times. The data measured with VICON were processed using Visial3D.V4, and the angles of the ankle, steps of the hemiplegic and non-hemiplegic sides, walking speed, walk rate and cadence were calculated. [Results] Compared to without a supporter, a supporter with 30 mmHg pressure showed a significant reduction in the angle of the knee at Initial Contact (IC), and a significant increase in the power of the knee extension at Loading Response (LR). [Conclusion] The results reveal a supporter with that of the subjects during pressure over 30 mmHg applied for 3 minutes improved the knee angle power and hemiplegia walking.

Biomechanical analysis of stair descent in patients with knee osteoarthritis.

[Purpose] The purposes of this study were to investigate the lower extremity joint kinematics and kinetics of patients with the knee osteoarthritis (knee OA) during stair descent and clarify the biomechanical factors related to their difficulty in stair descent. [Subjects and Methods] Eight healthy elderly persons and four knee OA patients participated in this study. A 3-D motion analysis system and force plates were employed to measure lower extremity joint angles, ranges of motion, joint moments, joint powers, and ratios of contribution for the joint powers while descending stairs. [Results] Knee joint flexion angle, extension moment, and negative power during the early stance phase in the knee OA group were smaller than those in the healthy subjects group. However, no significant changes in these parameters in the ankle joint were observed between the two subject groups. [Conclusion] Knee OA patients could not use the knee joint to absorb impact during the early stance phase of stair descent. Hence, they might compensate for the roles played by the intact knee joint by mainly using ipsilateral ankle kinematics and kinetics.

Kinetic and kinematic parameters associated with late braking force and effects on gait performance of stroke patients.

Late braking force (LBF) is often observed in the late stance phase of the paretic lower limb of stroke patients. Nevertheless, the effects and association of LBF remain unclear. We examined the kinetic and kinematic parameters associated with LBF and its effect on walking. Herein, 157 stroke patients were enrolled. Participants walked at a comfortable speed selected by them, and their movements were measured using a 3D motion analysis system. The effect of LBF was analyzed as a linear relationship with spatiotemporal parameters. Multiple linear regression analyses were performed with LBF as the dependent variable and kinetic and kinematic parameters as independent variables. LBF was observed in 110 patients. LBF was associated with decreased knee joint flexion angles during the pre-swing and swing phases. In the multivariate analysis, trailing limb angle, cooperativity between the paretic shank and foot, and cooperativity between the paretic and non-paretic thighs were related to LBF (p < 0.01; adjusted R2 = 0.64). LBF in the late stance phase of the paretic lower limb reduced gait performance in the pre-swing and swing phases. LBF was associated with trailing limb angle in the late stance, coordination between the paretic shank and foot in the pre-swing phase, and coordination between both thighs.

Trunk orthosis with joints providing resistive force improves dynamic sagittal alignment in postoperative patients with lumbar spinal stenosis.

This study aimed to determine whether a trunk orthosis with joints providing resistive force (TORF) modifies sagittal malalignment during level walking in patients with lumbar spinal stenosis (LSS). Fifteen patients, 6 months after undergoing surgery for LSS, performed level walking at a self-selected speed while wearing a TORF. Dynamic sagittal alignment, including sagittal vertical axis, lumbar lordosis, and pelvic tilt, and spatiotemporal data as well as lower limb kinematic and kinetic data were recorded using a three-dimensional motion analysis system and six force plates. Statistical analysis was performed to compare these data with and without the TORF, respectively. Compared to the condition without the TORF, the use of the TORF significantly decreased positive sagittal vertical axis (p < 0.05) and increased the lumbar lordosis and pelvic tilt (p < 0.05). Peak hip flexion angle and extension moment during loading response (LR) significantly increased (p < 0.05), and peak hip extension angle and flexion moment during PS statistically decreased (p < 0.05). There was no difference in spatiotemporal data between the two conditions. Our findings suggest that TORF may modify the dynamic sagittal global alignment and lower limb kinematic and kinetics in postoperative LSS patients during level walking.

Relationship between the locomotive syndrome and kinetic and kinematic parameters during static standing and level walking.

BACKGROUND: Individuals experiencing age-related decline in locomotor functions are at high-risk of developing locomotive syndrome (LS). LS requires long-term care and greatly influences the quality of life and activities of daily living. The LS risk test was established as a diagnostic criterion by the Japanese Orthopedic Association. Although the relationship between the test and motor function has been established, few studies have reported on the characteristics of LS kinematically and kinetically. RESEARCH QUESTION: Do elderly with LS show different kinetic and kinematic characteristics compared with healthy elderly during static standing and level walking? METHODS: Forty-four Participants were divided into an LS group and a non-LS group based on the scores of the LS risk test. The standing posture and walking of the participants were measured using a three-dimensional motion capture system. The results of the groups were compared using an unpaired t-test, and then the characteristics of the LS group were extracted using logistic regression analysis. RESULTS: LS group exhibited trunk flexion during both standing and gait. A higher intervertebral disc compressive force, which is the index of the low-back mechanical stress, during standing and an increase in ankle plantarflexion angle during walking were observed in LS group. SIGNIFICANCE: This study determined the kinematic and kinetic features of elderly with LS. The findings suggest that parameters related to the trunk and ankle could be associated with LS. Further studying the characteristics of LS in older adults via motion analysis can help develop prevention and intervention methods for LS.

Comparison of low back joint moment using a dynamic 3D biomechanical model in different transferring tasks wearing low back belt.

The purpose of this study was to construct a 3D dynamic model to quantify low back load during single person dependent transfer, and to compare the effects of wearing style of a low back belt on low back loading. Of the nine subjects participating in this study, eight adopted the role of caregiver and one was a simulated patient. Tasks were general transfer without either subject wearing a low back belt (WB), transfer with the patient wearing a low back belt (BP), transfer with both subjects wearing low back belts (BB), and transfer with the caregiver wearing a low back belt (BC). Low back lateral and extension moments in BB and BC transfers showed the significantly smaller values than those in WB transfers (p<0.01). The results suggest that the wearing of a low back belt by caregivers would reduce low back joint moment during transfers.

Effects of diabetic peripheral neuropathy on gait in vascular trans-tibial amputees.

BACKGROUND: Patients with diabetes often develop diabetic peripheral neuropathy, which is a distal symmetric polyneuropathy, so foot function on the non-amputated side is expected to affect gait in vascular trans-tibial amputees. However, there is little information on the kinematics and kinetics of gait or the effects of diabetic peripheral neuropathy in vascular trans-tibial amputees. This study aimed to clarify these effects, including the biomechanics of the ankle on the non-amputated side. METHODS: Participants were 10 vascular trans-tibial amputees with diabetic peripheral neuropathy (group V) and 8 traumatic trans-tibial amputees (group T). Each subject's gait was analyzed at a self-selected speed using a three-dimensional motion analyzer and force plates. FINDINGS: Ankle plantarflexion angle, heel elevation angle, and peak and impulse of anterior ground reaction force were smaller on the non-amputated side during pre-swing in group V than in group T. Center of gravity during pre-swing on the non-amputated side was lower in group V than in group T. Hip extension torque during loading response on the prosthetic side was greater in group V than in group T. INTERPRETATION: These findings suggest that the biomechanical function of the ankle on the non-amputated side during pre-swing is poorer in vascular trans-tibial amputees with DPN than in traumatic trans-tibial amputees; the height of the center of gravity could not be maintained during this phase in vascular trans-tibial amputees with diabetic peripheral neuropathy. The hip joint on the prosthetic side compensated for this diminished function at the ankle during loading response.

Association of low back load with low back pain during static standing.

BACKGROUND: Although poor standing posture is a known cause of low back pain, the mechanisms involved are unclear. The aim of this study was to clarify the kinetic and posture angle features of standing posture that might influence low back pain. METHODS: Sixty-seven young men were enrolled in this cross-sectional case-control study and were categorized according to whether they did or did not have low back pain. Habitual standing posture was assessed in each group, using a three-dimensional motion analysis system, force plates, and a spinal mouse. Kinetic and posture angle factors were compared between participants with and without low back pain. The relationship between specific features of standing posture and low back pain was analyzed using logistic regression. RESULTS: The intervertebral disc compressive force and the low back moment were significantly greater in the group with low back pain than in the group without low back pain. The intervertebral disc compressive force was the factor most strongly associated with low back pain during static standing. CONCLUSIONS: Logistic regression analysis identified intervertebral disc compressive force as an independent variable associated with low back pain. This finding suggests that increased intervertebral disc compressive force may promote development of low back pain in standing posture.

Kinetic and kinematic variables affecting trunk flexion during level walking in patients with lumbar spinal stenosis.

Lumbar spinal stenosis causes cauda equina and nerve root compression, resulting in neurological symptoms. Although trunk flexion during level walking may alleviate these symptoms by enabling spinal canal decompression, some patients do not use this strategy. We aimed to identify the kinetic and kinematic variables that affect trunk flexion in patients during level walking. Gait was recorded in 111 patients using a three-dimensional motion capture system and six force plates. From the data recorded, walking velocity, bilateral step length, cycle time, maximum trunk flexion angle, forward pelvic tilt angle, pelvic rotation angle, maximum and minimum joint angles, and moment and power of the lower limb were calculated. Then a step-wise multiple regression analysis was conducted to identify kinetic and kinematic variables affecting trunk flexion. The maximum hip extension angle (ß = 0.416), maximum hip flexion moment (ß = -0.348), and step length (ß = 0.257) were identified as variables significantly affecting the trunk flexion angle. The coefficient of determination adjusted for the degree of freedom was 0.294 (p < 0.05). Our results suggest that patients with lumbar spinal stenosis choose one of two strategies to alleviate symptoms during walking. One strategy is gait with trunk flexion posture to increase step length and hip extension angle. The other strategy is gait with trunk upright posture to decrease step length and hip extension angle.