Inter-tester Reliability of Lumbar Lordosis Posture Classification Using a Novel Screening Device.

OBJECTIVE: The purpose of this study was to investigate the inter-tester reliability of lumbar lordosis posture using a novel screening device. METHODS: A total of 33 healthy young male participants participated in the study. Two examiners measured the regional upper and lower lumbar lordosis angles of the participants in the standing position using a flexible ruler. The bent flexible ruler maintained a fixed shape and was transferred to a protractor for angle measurement. Two examiners classified each participant into one of 4 lumbar spine categories and measured the upper and lower regional lumbar lordosis angles. RESULTS: The agreement level between the 2 examiners in assessing healthy participants was 87.9%. The calculated kappa coefficient was 0.79 (95% CI = 0.86-0.97), reflecting a substantial level of agreement. CONCLUSION: Our results suggest that our novel screening device for assessing upper and lower lumbar angles showed good inter-tester reliability in posture classification. Our findings may be useful for health care professionals for managing sagittal lumbar posture in asymptomatic younger individuals; however, more testing is still needed.

The effect of sagittal hip angle on lumbar and hip coordination and pelvic posterior shift during forward bending.

PURPOSE: The purpose of this study was to investigate the effects of dynamic sagittal hip angle on lumbar and hip coordination and pelvic posterior shift during forward bending. METHODS: A total of 44 asymptomatic younger female volunteers were recruited to this study. Following measurement of trunk forward bending, participants were divided into three groups based on hip flexion angle: group 1, < 30°; group 2, ≥ 30° and < 50°; and group 3, ≥ 50°. Lumbar spine and hip coordination and pelvic backward shift were recorded during trunk forward bending using a three-dimensional ultrasonic motion analysis system. RESULTS: Pelvic and total angles increased with hip angle (group 3 > group 2 > group 1; p = 0.003 and p < 0.001, respectively), whereas lumbar/hip and pelvic/hip angle ratios decreased significantly (p < 0.001). The degree of pelvic posterior shift increased to a limited extent, whereas the pelvic posterior shift/hip angle ratio decreased significantly (p < 0.05). CONCLUSIONS: Asymptomatic subjects with limited hip flexion showed reduced total pelvic anterior rotation and greater relative proportion of pelvic motion than insufficient hip motion. These subjects tended to increase the pelvic posterior shift/hip angle ratio during trunk forward bending, possibly increasing passive tension by elongating the hamstring muscles to increase hip motion. The results of this study provide information that will improve the assessment of lumbar spine and hip coordination patterns and facilitate movement strategies by determining the specific requirements of individuals. These slides can be retrieved under Electronic Supplementary Material.

Lumbar Movement Dysfunction Based on Movement Control Impairment Classification System in Those Who Do and Do Not Develop Transient Low Back Pain During Prolonged Sitting.

OBJECTIVE: Long-term sitting triggers movement-related disorders. We used a movement control impairment (MCI) system to investigate lumbar movement dysfunction in those who did and did not develop transient low back pain (LBP) during prolonged sitting. METHODS: Twelve patients who did and did not develop transient LBP during sitting for 2 hours were enrolled. We tested the movement control abilities of the 2 groups using 6 MCI tests (12 test items). RESULTS: The mean MCI test score in the transient LBP developer group was significantly higher than that in the LBP non-developer group (P = .03). Lumbar flexion movement control as the backward rocking test was significantly more common in the transient LBP developer than in the LBP non-developer group (P < .027). Pelvic shifting and asymmetry during side-bending of the trunk were evident in both groups (all P > .05). However, pelvic shifting during side-bending of the trunk was evident only in the LBP group (33%; P = .093). CONCLUSION: The group exhibiting transient LBP had higher positive MCI test scores and exhibited more asymmetry than the other group. Even the non-LBP group exhibited poor lumbar flexion and rotation. Therefore, subjects with subclinical dysfunction caused by prolonged sitting may require homogenous subgroups classification for the early detection of mechanical risk factors and health and functional interventions.

The Intertester Reliability of a Modified Movement System Impairment Classification System Used to Evaluate Individuals With Prolonged Sitting: A Preliminary Study.

OBJECTIVE: Prolonged sitting while working at a computer leads to poor sitting postures, which can aggravate low back pain in many individuals. We examined the intertester reliability of using the modified musculoskeletal impairment schema for classifying participants sitting at computers for prolonged times. METHODS: Fifty participants were examined independently by each therapist using a test-retest design. Each therapist assigned an musculoskeletal impairment classification upon completion of the examination. The agreement percentages and the kappa coefficient were used to evaluate intertester reliability in classifying participants with prolonged sitting. RESULTS: The percentage agreement between the 2 examiners for participants who maintained the sitting posture for prolonged times was 84%. The calculated kappa coefficient was 0.73, reflecting a substantial level of agreement. CONCLUSIONS: The present findings provide some evidence to support the classification of individuals who sit at computers for prolonged times and participants with rotation with flexion pattern would need to manage asymmetry pattern in a subclinical group.

Inertial Measurement Unit-based Evaluation of Global and Regional Lumbar Spine and Pelvis Alignment in Standing Individuals With a Flat Lumbar Posture.

OBJECTIVE: The purpose of this study was to investigate the global and regional lumbar spine and pelvis postural alignment in standing individuals with a flat lumbar posture using an inertial measurement unit (IMU) system. METHODS: A total of 80 symptomatic young volunteers (25 men and 55 women in their early 20s) were recruited at Inje University in Gimhae, South Korea for this study. Participants stood in a comfortable posture for 5 seconds with IMUs on the T10, L3, and S2 level. Participants were then categorized into 3 groups according to the global lumbar lordosis (GLL) angle (T10-S2): <20°, 20° ≤ GLL angle < 30°, and 30° ≤ GLL angle < 40°. We compared the GLL and regional lumbar lordosis (RLL) angles among the 3 groups. RESULTS: As GLL increased, RLL angles (upper, P = .001; lower, P < .001) tended to increase, whereas the sacrum angle decreased (P < .001). A stepwise regression model showed that the sacrum angle was the single best predictor of GLL in standing participants. Based on IMU measurements, participants with GLL <20° are considered representative of participants with a flat lumbar posture. CONCLUSION: Posture measurements in a standing position conducted to assess lordosis should consider the relationship between GLL and RLL rather than GLL or RLL alone. We found that S2 was the best predictor of GLL.

Effects of lengthwise postural taping for lumbar spine rotation with flexion syndrome: a case report.

[Purpose] This study investigated the effects of lengthwise postural taping on a patient having lumbar spine rotation with flexion syndrome during prolonged periods of sitting. [Subject and Methods] The subject was a 22-year-old woman who had developed transient low back pain in the lumbo-pelvic region. The subject was asked to sit in a chair during 30 minutes of computer work under three conditions: no taping, extensive lumbo-pelvic region taping, and lengthwise lumbo-pelvic region taping. The center of force and mean peak gluteal pressure were measured using a TekScan system. [Results] With extensive taping, the AP center of force progressively decreased after 10, 20, and 30 min, while the ML center of force differed only slightly by time point. With lengthwise taping, the ML and AP center of force decreased after 20 min. [Conclusion] These findings suggest that lengthwise taping is a useful method for patients having lumbar rotation with flexion syndrome to prevent slumped sitting posture and excessive pressure on the gluteal muscles.

Effects of task velocity and center of mass acceleration during Y-Balance Test in elderly females with good and poor visual acuity.

[Purpose] To explore the effects of good binocular visual acuity (BVA) compared to poor BVA, reach distance, task velocity, and center of mass (COM) acceleration were evaluated in elderly females performing the Y-Balance Test (YBT) using a cross-sectional design. [Subjects and Methods] A total of 13 participants had BVA of ≥0.4 log of the minimum angle of resolution (logMAR) (poor BVA group), and the other 13 had BVA of ≤0.3 logMAR (good BVA group). An accelerometer was attached over participants' L3 spinous process, and they then performed the YBT. [Results] The normalized reach distances in the three directions among the good BVA group were longer than those among the poor BVA group. The task velocity in the good BVA group was significantly higher, whereas COM acceleration in the A direction was significantly lower compared with the poor BVA group. [Conclusion] Visual status must be considered when older adult individuals undergo physical therapy and functional training to ensure that healthcare professionals can better assist older adult women.

Differences in gait velocity and trunk acceleration during semicircular turning gait with and without bag in females of very advanced age.

[Purpose] Gait velocity and trunk acceleration during semicircular turning gait with and without carrying a hand-held bag were compared in females of very advanced age. [Subjects and Methods] Ten female volunteers of very advanced age who could walk independently were recruited for this study. Gait velocity and trunk acceleration were measured using an accelerometer during semicircular turning gait with and without carrying a hand-held bag. [Results] Gait velocity during semicircular turning gait was greater with the bag than without the bag. [Conclusions] Trunk stability during semicircular turning gait was higher when the subjects carried a bag. Additional arm load could be considered during gait training in females of very advanced age.

Comparison of trunk acceleration ratios during stair negotiation in old-old females.

[Purpose] This study compared trunk acceleration ratios in old-old adult females during stair negotiation. [Subjects and Methods] Twelve old-old adult females who could walk independently volunteered for this study. This study measured gait time and trunk acceleration ratios using an accelerometer during ascending and descending stairs [Results] The trunk acceleration ratio when descending stairs was significantly higher than that when ascending stairs. [Conclusion] These findings suggest that old-old females have greater deterioration of upper trunk control function for descending than for ascending stairs, regardless of task time. In addition, the trunk acceleration ratio during stair negotiation is a useful clinical marker to predict function and balance control ability in old-old females.

The effects of gait time and trunk acceleration ratio during stair climbing in old-old adult females.

[Purpose] This study investigated the effects of gait time and trunk acceleration ratio in old-old adult females during stair climbing. [Subjects and Methods] Twenty-five older adult females who were able to walk independently volunteered for this study and were categorized into two age groups (older adults or old-old adults). Gait time and trunk acceleration ratio were measured using an accelerometer during stair climbing. [Results] Gait time and trunk acceleration ratio when climbing stairs were significantly higher in the old-old age group than in the older adults group. [Conclusions] These findings suggest that old-old females have decreased upper trunk control. In addition, gait time and the trunk acceleration ratio during stair climbing are useful clinical markers for predicting function and balance control ability in old-old elderly populations.

Comparison of energy expenditure during the Y-balance test in older adults with different visual acuities.

[Purpose] This study compared the energy expenditure during the Y-balance test (YBT) between elderly women with good binocular visual acuity (BVA) and those with poor BVA. [Subjects] Twenty-one elderly women who could walk independently were recruited from a community dwelling. Eleven participants had a BVA equal to or less than 0.4 logarithm of the minimum angle of resolution (logMAR), and the other 10 participants had a BVA equal to or better than 0.3 logMAR. [Methods] The participants had an accelerometer attached over the L3 spinous process for measurement of energy expenditure and performed the YBT in the anterior, posteromedial, and posterolateral directions. [Results] The normalized reach distance in the good BVA group during the YBT in three directions and composite reach distance were significantly longer compared with the values in the poor BVA group. The energy expenditure in the good BVA group during the YBT in the three directions was significantly reduced compared with the values in the poor BVA group. [Conclusion] We suggest that visual acuity in the elderly influences dynamic balance and energy expenditure. Elderly subjects with poor BVA showed poor dynamic balance control and an inefficient biomechanical cost strategy compared to subjects with good BVA.

Effects of gait velocity and center of mass acceleration during turning gait in old-old elderly women.

[Purpose] This study investigated gait velocity and center of mass acceleration in three directions during square and semicircular turning gait tasks in old-old elderly women. [Subjects] Fifteen community-dwelling, old-old elderly women (≥75 years old) who could walk independently were recruited. [Methods] We measured gait velocity and center of mass acceleration in three directions using an accelerometer during two different turning gait tasks. [Results] The velocity during square turning was significantly slower than that during semicircular turning gait. There were no significant differences between gait tasks with respect to normalized antero-posterior, medo-lateral, or vertical center of mass acceleration. [Conclusion] Changing the direction of travel while walking regardless of turning angle is one of the greatest challenges for balance in old-old elderly people. Furthermore, gait velocity is a useful clinical marker for predicting falls in old-old elderly populations.

Comparison of gait velocity and center of mass during square and semicircular turning gaits between groups of elderly people with differing visual acuity.

[Purpose] The purpose of this study was to investigate gait velocity and center of mass (COM) during square and semicircular turning gaits between two groups of elderly people with differing visual acuity. [Subjects] Twenty elderly Korean women who could walk independently and who lived in the community were recruited. [Methods] We measured gait velocity and COM using an accelerometer during two different turning gaits. [Results] The velocity during square and semicircular turning gaits of participants with good binocular visual acuity (GBVA) was significantly higher than that of participants with poor binocular visual acuity (PBVA). The COM during square and semicircular turning gaits of the GBVA group was significantly decreased compared with that of the PBVA group. [Conclusion] These findings suggest that visual acuity affects velocity and COM during square and semicircular turning gaits of elderly people.

The Effect of Motor Dual-task Balance Training on Balance and Gait of Elderly Women.

[Purpose] This study investigated the effect of a motor dual-task balance program on balance and gait of elderly women to suggest a more effective balance exercise method. [Subjects] Twenty elderly Korean women who could walk independently were recruited from the community dwelling. [Methods] The motor dual-task balance training (experimental) group stood on an Aero-step, and performed gym ball bouncing, catching, and throwing, while the simple task balance training (control) group merely stood on the Aero-step. Participants performed 45 minutes of training, 2 times a week for 6 weeks. Balance (fall index) was measured using a TETRAX. Gait variables were recorded on a GAITRite walkway at self-determined walking speed. [Results] The fall index of the experimental group was significantly lower than that of the control group. Step length, stride length, velocity, and cadence of the experimental group improved significantly more than those of control group. [Conclusions] We found that motor dual-task balance training improved balance and walking ability more than simple balance training. Further studies should investigate motor dual-task training with kinematic and kinetic data, and muscle activation based on motor strategies.

The difference in the relationship of spinal sagittal alignment between individuals with flat lumbar and normal lordosis posture based on global and regional angles.

BACKGROUND: According to previous studies, the relationship between lumbar lordosis and thoracic kyphosis or that between pelvic parameters and thoracic kyphosis have been inconsistent. OBJECTIVE: The purpose of this study was to investigate spinal sagittal alignment and its relationship to global and regional lumbar and thoracic angles, pelvic and sway angles, and C7-S1 distance measurements, followed by a detailed subgroup analysis using an inertial measurement unit system. METHODS: A total of 51 asymptomatic volunteers stood in a comfortable posture with inertial measurement units attached to the T1, T7, T12, L3, and S2 vertebrae. T1, T7, T12, L3, and S2 sagittal angles were acquired during standing posture using the Eulerian angle coordinate system. All angles are reported as the mean of three 5-s measurements. Following the measurement of lumbar lordosis angles (T12 relative S2), participants were divided into the flat lumbar and normal lordosis groups. RESULTS: There were different correlation patterns between groups because of spinal sagittal imbalance, which was greater in the flat lumbar group than in the normal lordosis group. In addition, sacral inclination proved the ideal parameter to evaluate reciprocal balance in lumbar lordosis, showing a stronger correlation with lower than with upper lumbar lordosis. T1 was the key element in assessing thoracic kyphosis, which showed a stronger correlation with upper than with lower thoracic kyphosis. CONCLUSION: We suggest that when assessing posture, it is necessary to identify the global and regional angles and it is useful to classify spinal sagittal alignment into subgroups according to lumbar lordosis and evaluate the groups separately.

Impact of step width on trunk motion and gait adaptation in elderly women with knee osteoarthritis.

BACKGROUND: Step width during walking can provide important information about aging and pathology. Although knee osteoarthritis (OA) is a common disease in elderly women, little is known about how different step widths influence gait parameters in patients with knee OA. OBJECTIVE: To address this, we investigated the differences between narrower and wider step width on the center of mass (CoM) and gait biomechanics of elderly women with knee OA. METHODS: Gait and CoM data were measured using a three-dimensional motion capture system and anthropometric data were acquired via standing full-limb radiography. Thirty elderly women with knee OA were divided into two groups depending on the average step width value (0.16 m). Specifically, the narrower step width group included those with a below average step width (n= 15) and the wider step width group included those with an above average step width (n= 15). The differences between the two groups were analyzed using an independentt-test. RESULTS: Walking speed, step length, knee and ankle sagittal excursion, and medial-lateral CoM range were significantly greater in the narrower group. In contrast, the medial-lateral CoM velocity, medial-lateral ground reaction force (GRF), and foot progression angle were significantly higher in wider group. The external knee adduction moment, vertical GRF, and vertical CoM did not differ between the groups. CONCLUSIONS: Our data indicate that step width in women with knee OA is associated with trunk motion and gait patterns. People with a narrower step might improve their gait function by increasing trunk frontal control to maintain gait stability. In contrast, in those with a wider step, greater toe out angle and shorter step length might be a compensatory adaptation to reduce knee loading.

Assessing the effects of sway-back posture on global and regional spinal sagittal angles using inertial measurement units.

BACKGROUND: Sway-back posture in the sagittal profile is a commonly adopted poor standing posture. Although the terms, definitions, and adverse health problems of sway-back posture are widely used clinically, few studies have quantified sway-back posture. OBJECTIVE: To investigate spinal sagittal alignment in sway-back posture while standing based on global and regional angles using inertial measurement units (IMUs). METHODS: This cross-sectional study recruited 30 asymptomatic young adults. After measuring the sway angle while standing, the participants were divided into sway-back and non-sway-back groups (normal thoracic group). Each participant stood in a comfortable posture for 5 seconds with IMUs at the T1, T7, T12, L3, and S2 levels. Then, we measured the global and regional lumbar and thoracic angles and sacral inclination in the standing position. RESULTS: Although there was no difference in the global lumbar angle, there was a difference in regional lumbar angles between the two groups. The normal thoracic group had balanced lumbar lordosis between the upper and lower lordotic arcs, whereas the sway back group tended to have a flat upper lumbar angle and increased lower lumbar angle. CONCLUSION: It is useful to assess the global and regional angles in the spinal sagittal assessment of individuals with sway-back posture.

The effects of differences on sagittal kinematics and muscle coordination during step up and step down in patients with spinal stenosis.

BACKGROUND AND OBJECTIVE: Lumbar spinal stenosis (LSS) is a common spinal disorder that causes patients to assume a forward-trunk posture. Spinal alignment affects swing limb angles and stance limb muscle activities. Therefore, we investigated the effects of differences in step up (SU) and step down (SD) tasks on the kinematics of the trunk and swing limb as well as stance limb muscle coordination in patients with LSS. METHODS: Nine elderly female patients diagnosed with LSS were recruited for this study. The sagittal kinematics of the trunk and swing limb and isolated contraction ratio of the gluteus medius (GMed) and vastus lateralis (VL) during SU and SD tasks were measured using a motion analysis system and surface electromyography system. RESULTS: Thoracic (17.71∘± 7.77∘) and spine angles (13.64∘± 11.34∘) as well as swing hip (48.48∘± 12.76∘) and pelvic angles (7.52∘± 10.33∘) were significantly greater during SU than SD (10.14∘± 8.41∘, 10.03∘± 11.03∘, 29.42∘± 10.57∘, 3.21∘± 10.11∘, all P< 0.05, respectively). The isolated contraction ratio of the GMed of the stance limb (34.12% ± 13.28%) was significantly higher during SU than during SD (26.65% ± 10.02%), whereas that of the VL of the stance limb (65.88% ± 13.28%) was significantly lower during SU than during SD (73.35% ± 10.02%, P= 0.011 for both comparisons). CONCLUSIONS: Patients with LSS demonstrated trunk compensatory mechanisms to address swing hip and knee angles. Trunk position affected pelvic limb muscle coordination in the standing support limb. These findings demonstrate that SD are more challenging than SU for patients with LSS, possibly due to reduced ability to generate adequate leg extensor muscular output to safely control the motion of the body's center of mass. Therefore, trunk positions must be considered when patients with LSS undergo rehabilitation programs, particularly those involving SD or descending stairs, so that healthcare professionals can better assist patients with LSS. In addition, this study provides a background for further studies.

Differences in regional and global lumbar angle during slumped sitting and upright sitting among global three subgroups.

OBJECTIVE: The purpose of this study was to investigate differences in regional lumbar lordosis (RLL) and global lumbar lordosis (GLL) angle during slumped sitting and upright sitting among three global subgroups. METHODS: A total of 48 young asymptomatic volunteers stood in a comfortable posture, sat upright, and sat in a slumped position for 5 seconds, with inertial measurement units attached to the T10, L3, and S2 vertebrae. According to standing measurement, the participants were categorized into flat-back (GLL < 20∘), normal lordosis (20∘⩽ GLL < 30∘), and hyper-lordosis (30∘⩽ GLL < 40∘) groups. RESULTS: Both the GLL and RLL in the flat-back group were reduced lumbar lordosis in the upright sitting posture and increased lumbar kyphosis in the slumped sitting postures compared to the other groups (p< 0.05), but the range of motion during the transition from upright sitting to slumped sitting was lower than that of the normal and hyper-lordosis groups (p< 0.05). GLL in standing was a moderate correlation with GLL and RLL during upright sitting (p< 0.05). However, there was a strong correlation between GLL and RLL kinematics during upright and slumped sitting (p< 0.05). CONCLUSIONS: Flat-back posture is a potential source of low back pain during both upright and slumped sitting compared to the normal and hyper-lordosis groups. Posture measurements in a standing and sitting position conducted to assess lordosis should consider the relationship between GLL and RLL.

Stepping over an obstacle in patients with lumbar spinal stenosis: Trunk and lower extremities of kinematic and muscle activation normalized by double limb support. A preliminary study.

BACKGROUND: Patients with LSS tend to adopt a flexed lumbar posture and trunk position, particularly when stepping over an obstacle, as this activity alters the biomechanical demands placed on the trunk and lower extremities. OBJECTIVE: To investigate the effects of lumbar spinal stenosis (LSS) on patients' trunk and lower-extremity kinematics, and on activities involving the gluteus medius (GMed) and vastus lateralis (VL). METHODS: All participants (9 older adult patients with LSS and 11 control subjects) were required to negotiate an obstacle while walking. Trunk and lower-extremity kinematic data and GMed and VL activities were recorded using a synchronized 3D motion capture system and surface electromyography. RESULTS: The thoracic (12.01∘± 8.82∘ and 16.45∘± 10.80∘) and spinal (9.92∘± 14.03∘ and 5.99∘± 15.94∘) flexion angles of the leading and trailing swing limbs were higher, and the pelvic anterior tilting angle (2.37∘± 7.76∘ and 10.38∘± 8.07∘) was lower in the LSS group than in the control group (p< 0.05). With the exception of toe-off and normalized GMed activities in the contralateral leading limb (p> 0.05), all GMed (256.73 ± 112.22%, 174.00 ± 75.79%, and 270.57 ± 114.45%, respectively) and VL (208.98 ± 124.81%, 182.97 ± 93.23%, 283.91 ± 154.71%, and 394.42 ± 108.94%, respectively) activities of the contralateral leading and trailing swing limb (heel-strike and toe-off normalized activities) were significantly higher in the LSS group than in the control group (p< 0.05). CONCLUSIONS: Patients with LSS exhibited trunk-flexed postures when stepping over an obstacle, and these trunk alignments placed higher demands on the GMed and VL activities normalized by double-limb support during joint loading in the single-leg stance. These findings support clinical recommendations for regulating the physical activity of obstacle negotiation that may be beneficial in the management of patients with LSS.