Sensory Organization and Postural Control Strategies in Individuals With Mild and Moderate-to-Severe Forward Head Posture: A Comparative Study.

OBJECTIVE: This study aimed to compare sensory organization test and postural control strategies between individuals with mild and moderate-to-severe forward head posture (FHP). METHODS: A sensory organization test (SOT) was performed in 6 conditions using computerized dynamic posturography, to assess postural control. Equilibrium scores representing overall balance, strategy analysis to assess ankle vs hip strategy dominance, and sensory analysis (Somatosensory, visual, vestibular, visual preference ratio) as an indicator of the use of sensory systems were obtained. RESULTS: Our results revealed a significant difference between the 2 groups in terms of equilibrium score (P < .05) and strategy scores (P < .05) in conditions of 4 to 6 of the SOT. The results of sensory analysis of SOT showed visual and vestibular ratios were significantly different between the 2 study groups (P < .05), but somatosensory and visual preference ratios were not significantly different between these 2 groups (P > .05). CONCLUSION: Individuals with moderate-to-severe FHP swayed more in comparison with mild FHP ones in conditions with the Sway-referenced platform of the SOT. They tended to rely on the hip strategy more than the ankle strategy excessively when sensory difficulty increased. Overall, it can be concluded that individuals with moderate-to-severe FHP are more likely to have postural deficits.

Effects of exergaming on cognition, lower limb functional coordination, and stepping time in people with multiple sclerosis: a randomized controlled trial.

PURPOSE: To compare the effects of exergaming versus conventional exercises on cognition, lower-limb functional coordination, and stepping time in people with multiple sclerosis (PwMS). METHODS: Thirty-six PwMS were randomly assigned to either intervention (n = 18) or control (n = 18) group and received 18 training sessions during six weeks. The intervention group performed exergames that required multidirectional timed-stepping, weight-shifting, and walking while the control group performed conventional matched exercises. Trail making test (TMT part A, B; TMT-A, TMT-B, TMT B-A), six-spot step test (SSST), and choice stepping reaction time (CSRT-including reaction time (RT), movement time (MVT), and total response time (TRT)) were assessed pre- and post-intervention (short-term), and after three-month follow-up (mid-term). RESULTS: The intervention group showed faster TMT-B (p = 0.003) and TMT B-A (p = 0.002) at post-intervention and faster SSST at both post-intervention (p = 0.002) and follow-up (p = 0.04). The CSRT components showed no between-group differences at post-intervention; however, at follow-up, the intervention group had lower TRT (p = 0.046) and MVT (p = 0.015). TMT-A and RT had no significant between-group differences. CONCLUSIONS: In short-term, exergames led to more improvements in complex attention, executive function, and lower-limb functional coordination comparing to the matched conventional exercises. In mid-term, exergaming was more effective for improving stepping time and lower-limb functional coordination. However, the two approaches did not show any superiority over each other for improving simple attention and RT.Implications for rehabilitationWhen designed properly, exergames have great potential to improve attention and executive function of people with multiple sclerosis (PwMS), at least in the short-term.Exergames seem like an appropriate option for improving lower limb coordination and decreasing choice stepping response time among PwMS in the mid-term.Exergames do not have superiority in improving the choice stepping reaction time compared to their matched conventional treatment.

Comparison of proprioceptive postural control strategies between prolonged standing induced low back pain developers and non-low back pain developers.

BACKGROUND: Proprioception deficit has been suggested as a possible mechanism contributing for the impaired postural control in low back pain (LBP) patients. Whether proprioception deficit is a result of or a cause of LBP has not been investigated. OBJECTIVE: The purpose of this study was to compare proprioceptive postural control strategies between prolonged standing induced low back pain developers (PDs) and non-pain developers (NPDs). METHOD: Thirty-two healthy subjects performed 1-h prolonged standing and their ratings of perceived LBP have been recorded. Eight quiet standing trials for 60 s performed immediately before and after the prolonged standing. Postural control was challenged by muscle vibration and different postural conditions during quiet standing. Data were recorded using a force platform. RESULTS: Forty percentage of participants is classified as PD. Before the prolonged standing, relative proprioceptive weighting was greater in the PD compared to NPD group (P = .029). Main effect of postural condition (F1,24 = 5.21, P = .032) and interaction of time by group (F1,24 = 8.08, P = .009) were significant for COP displacement in anteroposterior direction. Interaction of postural condition by group (F1,26 = 7.82, P = .010) and time by group (F1,26 = 9.71, P = .004) were significant for COP displacement in mediolateral direction. Main effect of postural condition (F1,26 = 6.31, P = .018) and interaction of postural condition by group (F1,26 = 7.07, P = .013) were significant for mean velocity in mediolateral direction. CONCLUSION: The PD group has altered proprioceptive postural control strategies before and after prolonged standing. Proprioception deficit should not be considered to be solely an adaptive response and may be causal for LBP development.

Perturbation-based Balance Training to improve postural responses and falls in people with multiple sclerosis: a randomized controlled trial.

PURPOSE: To determine the effects of Perturbation-based Balance Training (PBT) on postural responses and falls in people with multiple sclerosis (PwMS) and compare the results with conventional balance training (CBT). MATERIALS AND METHODS: Thirty-four PwMS were randomized to receive 4 weeks of PBT or CBT. Latency of postural responses to external perturbations, Timed-Up-and-Go (TUG), 10-meter-walk (10MW), Berg Balance Scale (BBS), and Activities-specific Balance Confidence Scale (ABC) were measured at baseline and post-training. Also, the proportion of fallers and fall rate were assessed at a 3-month follow-up. RESULTS: The latency of postural responses significantly decreased in PBT compared to CBT. TUG, 10MW, BBS, and ABC, at post-training, and relative risk of falls and fall rate at 3-month follow-up had no statistically significant between-group differences. CONCLUSIONS: The results show that PBT is at least as effective as CBT in improving balance and decreasing falls, while it has superiority over CBT whenever the clinicians mainly aim to improve reactive balance strategies. Future studies with a larger sample size are warranted to complement the results of this study.Implication for rehabilitationPerturbation-based Balance Training is at least as effective as conventional balance training (CBT) in improving proactive postural control in people with multiple sclerosis (PwMS).Perturbation-based Balance Training has superiority over CBT in improving reactive postural control in PwMS.Perturbation-based Balance Training has no superiority over CBT in improving fall-related outcomes.

Validity and reliability of the Persian version of the STarT musculoskeletal tool.

BACKGROUND: The Subgrouping for Targeted Treatment (STarT) musculoskeletal (MSK) tool stratifies patients with MSK disorders (MSDs) into prognostic categories based on poor outcomes. PURPOSE: This study aimed at investigating the validity and reliability of the Persian STarT MSK tool in people suffering from painful MSDs in Iran. METHODS: A total of 593 subjects with painful MSDs including neck, shoulder, low back, knee, and multisite pain received and completed the STarT MSK tool, visual analog scale (VAS), EuroQol five-dimensions three-levels questionnaire (EQ-5D-3 L), short form-36 health survey questionnaire (SF-36), and Örebro musculoskeletal pain screening questionnaire (ÖMPSQ) in the first visit. To examine test-retest reliability, 234 patients completed the STarT MSK tool 2 days after the initial visit. RESULTS: In this study, 139 (23.5%), 266 (44.9%), and 188 (31.7%) participants were classified as low-, medium-, and high-risk groupings for poor outcomes, respectively. Spearman's correlation coefficient showed a strong relationship among Persian STarT MSK tool and EQ-5D-3 L (-0.78), SF-36 (-0.76), and OMPSQ (0.70). The results of known-group validity indicated that this tool could distinguish among the participants in different risk subgroups based on the scores of the ÖMPSQ, VAS, SF36, and EQ-5D-5 L (p < .001). No ceiling and floor effects were observed. Cronbach's alpha and intra-class correlation coefficient (ICC2,1) were acceptable (0.71) and excellent (0.98), respectively. CONCLUSION: The Persian version of STarT MSK tool has shown to be a valid and reliable instrument to stratify people with painful MSDs into low-, medium-, and high-risk subgroups based on persistent pain disability.

The Effect of Balance Training on Functional Outcomes in Patients with Knee Osteoarthritis: A Systematic Review.

Background: Knee osteoarthritis (OA) is a common musculoskeletal disorder that is associated with balance impairment. Recent studies have used balance exercises for improvement of balance and functional performance among knee OA patients. The purpose of this study was analyzing the effects of balance training in patients with knee OA. Methods: This review included clinical trials in which the effect of balance training on functional measures was assessed compared to other physiotherapy interventions or control groups in patients with knee OA. To this aim, Electronic databases (PubMed, SCOPUS, EMBASE, PEDro, CINAHL, and WOS) were searched from 1 January 1990 to 30 June 2021. Two independent reviewers selected the studies, extracted the data, and assessed the quality of the studies. Results: Fifteen articles of clinical trials were eligible to include in this review. Most studies used patient-reported outcome measures, and some studies used performance-based functional outcome measures for the evaluation of functional outcomes. The findings of studies showed that physical function in knee OA patients could have clinical improvements significantly after receiving balance training. However, studies assessing the effect of balance training on muscle strength of the quadriceps and the hamstring had conflicting results. Also, the finding of studies showed that more significant improvement in postural stability and balance in the balance training group rather than the control group. Conclusion: The results of the current systematic review demonstrate balance exercises significantly improve balance and functionality in knee OA patients. However, the effect of balance training on muscle strength was not clearly revealed due to few studies.

Validity, reliability, and responsiveness of Persian version of mini-balance evaluation system test among ambulatory people with multiple sclerosis.

BACKGROUND AND PURPOSE: Mini-Balance Evaluation Systems Test (mini-BESTest) is a widely used measure to assess balance impairments. This study aimed to assess the validity, reliability, responsiveness, and minimal clinically important change (MCIC) of the Persian mini-BESTest among ambulatory People with Multiple Sclerosis (PwMS). METHODS: Fifty ambulatory PwMS participated in this study. Persian mini-BESTest validated against Berg Balance Scale (BBS) and Timed-Up and Go (TUG) with/without a cognitive task. To assess the reliability, the Persian mini-BESTest was re-administered for a sample of 30 participants after 1 week. Also, 32 PwMS were tested before and after a 4-week of balance and gait training to assess the responsiveness. RESULTS: No floor/ceiling effect was found for the mini-BESTest total score. There were significant excellent correlations (p < .001) between mini-BESTest and BBS (r = 0.71), TUG (r = -0.76), and cognitive TUG (r = -0.73). No strong correlations were observed between the subscales (r = 0.37-0.55). Test-retest reliability and internal consistency of Persian mini-BESTest total score were excellent, with Intra-class Correlation Coefficient (ICC3,1 and Cronbach's alpha level of 0.89 and 0.80, respectively. The minimal detectable change was 4 points. The Persian mini-BESTest had acceptable responsiveness (AUC = 0.83), and MCIC was 5 points. CONCLUSION: The Persian mini-BESTest is a valid, reliable, and responsive measure of balance performance in Iranian ambulatory PwMS.

Comparison of Kinematic Movement Patterns Between 2 Subgroups of Females With Low Back Pain and Healthy Women During Sit-to-Stand and Stand-to-Sit.

The purpose of study was to compare the kinematic patterns of the thoracic, lumbar, and pelvis segments and hip joints between 2 low back pain subgroups and healthy women during sit-to-stand and stand-to-sit. Kinematic data of 44 healthy women and 2 subgroups of females with low back pain in 2 subgroups of movement system impairment model (rotation-extension [Rot.Ext] and rotation-flexion [Rot.Flex]) were recorded. Participants performed sit-to-stand and stand-to-sit at a preferred speed. Each task was divided into a pre buttock lifted off/on (pre-BOff/n) phase and a post-BOff/n phase. The Rot.Ext subgroup showed greater range of motion in the thoracic during pre-BOff phase of sit-to-stand (P < .001) and pre-BOn phase of stand-to-sit (P = .01) compared to the other 2 groups. The Rot.Flex subgroup displayed limited left hip joint excursion during sit-to-stand pre-BOff (P = .04) and stand-to-sit post-BOn phases (P = .02). The Rot.Flex subgroup showed greater pelvis tilt excursion during sit-to-stand post-BOff (P = .04) and stand-to-sit pre-BOn (P = .01) and post-BOn phases (P = .01). In subgroups of women with chronic low back pain, there were kinematic changes in adjacent body segments/joints of lumbar spine during sit-to-stand and stand-to-sit tasks.

Responsiveness and clinically meaningful changes for the Persian versions of the multiple sclerosis walking scale-12 and the modified fatigue impact scale following balance and gait rehabilitation in people with multiple sclerosis.

Background and Purpose: The Multiple sclerosis walking scale-12 (MSWS-12) and the Modified Fatigue Impact Scale (MFIS) are two popular outcome measures applied widely for assessing self-perceived walking ability and fatigue in people with multiple sclerosis (PwMS). The present study aimed to examine responsiveness and clinically meaningful changes for the Persian versions of the MSWS-12 and the MFIS following balance and gait rehabilitation in PwMS.Methods: Fifty-eight PwMS completed the Persian versions of the MSWS-12 and the MFIS before and after 4 weeks of balance and gait rehabilitation. Also, a 7-point global rating scale as an external criterion of change was completed at the post-intervention evaluation. The area under the receiver operating characteristics curve (AUC) and the correlation analysis were used to assess the responsiveness. In addition, the minimally clinically important change (MCIC) was measured to determine clinically meaningful changes following rehabilitation.Results: The AUC values for the Persian MSWS-12 and MFIS were 0.74 and 0.73, respectively. There were good to excellent correlations between the global rating scale of change and the Persian MSWS-12 (Gamma = 0.77) also MFIS (Gamma = 0.80) change scores (p = .001). Moreover, the MCICs of 7.5 and 4 points were obtained for the Persian MSWS-12 and MFIS, respectively.Conclusion: The Persian versions of the MSWS-12 and the MFIS were responsive outcome measures for monitoring changes in walking and fatigue after balance and gait rehabilitation in PwMS. The calculation of MCIC values would enhance the interpretation of changes in clinical and research settings.

Reliability of musculoskeletal ultrasonography for peri-ankle muscles in subjects with unilateral chronic ankle instability.

BACKGROUND: Ankle sprain is a common problem among active people and athletes. It causes reduces their activity of daily living and quality of life. Because of the impaired muscle strength and neuromuscular and postural control, it seems that the morphological criteria of peri-ankle muscles are changed. OBJECTIVE: This study aimed to develop a reliable method for measuring tibialis anterior (TA) and peroneus longus (PL) muscles in the injured and intact side of lower limbs in people with unilateral chronic ankle instability (CAI). STUDY DESIGN: Cross-sectional study. METHOD: This study was intra-tester reliability by ultrasound imaging to measure ultrasonography characteristics contains thickness, width, fiber length, pennation angle, and cross-sectional area (CSA) of TA, and PL in both limbs of 25 subjects at three separate times. Intra-class correlation coefficients (ICC), limits of agreement (LOA), standard error of measurement (SEM), and minimal detectable change (MDC) were calculated to analyzed relative and absolute intra-tester reliability, respectively. RESULTS: The present study showed good to excellent relative reliability for both injured and intact sides (ICC 0.88-0.98), less proportional measurement error (ß coefficient of LOA≈ 0), and suitable absolute reliability. CONCLUSION: Musculoskeletal ultrasonography is a reliable method for the measurement of peri-ankle muscle morphology such as thickness, width, CSA, fiber length, and pennation angle.

Cervical movement kinematic analysis in patients with chronic neck pain: A comparative study with healthy subjects.

BACKGROUND: Several studies have investigated cervical kinematic performance in patients with chronic neck pain, especially with fast movements. A recent systematic review recommended further study of cervical spine kinematics cervical motions in individuals with neck pain. OBJECTIVES: This study aimed to examine cervical spine kinematics of naturally paced cervical motions in patients with chronic neck pain compared with a group of asymptomatic participants. Also, the relationships between cervical kinematic measures with neck pain intensity and disability were determined. METHOD: Kinematic performance was measured in 20 individuals with chronic nonspecific neck pain and 20 healthy controls. Data were captured using a 7-camera motion analysis system. Parameters were range of cervical motion, peak velocity, duration of movement, and jerk index (smoothness of movement). Pain intensity and Neck Disability Index were also measured. RESULTS: Duration of movements, peak velocities, and jerk indexes were significantly different between the two groups (p < 0.05). Pain intensity was significantly associated with duration of movement, range of motion, peak velocity, and smoothness predominantly in extension (r range = 0.4 to 0.6, p < 0.05). CONCLUSION: This study's findings indicated altered cervical kinematic performance during naturally paced motions (particularly reduced smoothness of movement)in patients with chronic nonspecific neck pain compared to asymptomatic participants. Also, pain intensity was moderately associated with most kinematic measures, especially in extension. This study's results can help to understand better the impairments associated with chronic nonspecific neck pain.

Intersegmental kinematic analysis of lumbar spine by functional radiography between two subgroups of patients with chronic low back pain.

INTRODUCTION: Kinematic deficits such as fault in joint accessory motion is one of the most important contributing factors for developing the movement impairment in the lumbar spine. Functional radiography is accessible method for detecting the artherokinematic disorders. The aim of this study was to compare lumbar spine intersegmental motion between low back pain (LBP) subgroups of movement system impairment (MSI) model by functional radiography. MATERIALS AND METHODS: 20 subjects with chronic LBP in two subgroups of the MSI model (Rotation with Flexion and Rotation with Extension) participated in this study. Five x-rays were taken in different positions. Intersegmental linear translation and angular rotation of the lumbar segments were calculated. RESULTS: In the Rotation with Extension subgroup, the translation and rotation values of the L3-4 segment from full to full position were significantly more than their values in the Rotation with Flexion subgroup ((mean difference = -1.69 (mm) P = 0.01), (mean difference = -3.80 (mm) P = 0.02) respectively). The translation of L2-3 segment from the neutral to the mid-flexion position was significantly greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (mean difference = 1.12 (mm) P = 0.04). cumulative intersegmental angular rotation of all lumbar segments from mid to mid position was greater in the Rotation with Flexion subgroup compared to the Rotation with Extension subgroup (P = 0.03). CONCLUSION: Changes in intersegmental translation and angular rotation of lumbar segments in subgroups of patients with LBP may be important contributing factors that induce direction specific lumbar spine loads and contribute to the development or persistence of LBP problems.

Immediate Effect of Modifying Lumbopelvic Motion During Sitting Knee Extension in People With Low Back Pain: A Repeated-Measures Study.

Objective: The aim of this study was to investigate the ability of people with low back pain (LBP) to modify the pattern of lumbopelvic rotation (LPR) when actively moving their lower limbs in sitting. Methods: In this repeated-measures study in 38 men with chronic mechanical LBP (mean age, 38.4 ± 10.6 years), the timing and magnitude of LPR were investigated before and during the contraction of abdominal muscles during active knee extension while sitting. The kinematic data were collected using a motion-capture system, and OpenSim software was used for data analysis. The time difference between the start of knee extension and the start of LPR was measured and then adjusted to the movement time of the knee. The maximum LPR angle was also measured. Results: Participants increased the time difference between the start of knee extension and the start of LPR when contracting the abdominal muscles (P < .01). Before and during contraction of abdominal muscles, however, there were no differences in maximum LPR. Conclusion: People with LBP are able to modify early lumbopelvic motion during active lower limb movement while sitting. This may reduce the frequency of lumbopelvic motion during activities of daily living in sitting in these people.

Effects of Virtual Reality vs Conventional Balance Training on Balance and Falls in People With Multiple Sclerosis: A Randomized Controlled Trial.

OBJECTIVE: To assess the efficacy of virtual reality (VR)-based vs conventional balance training on the improvement of balance and reduction of falls in people with multiple sclerosis (PwMS). DESIGN: Single-blinded, randomized, controlled trial. SETTING: Musculoskeletal Rehabilitation Research Center, Ahvaz Jundishapur University of Medical Sciences. PARTICIPANTS: PwMS (N=39), randomized into VR (n=19) and control (n=20) groups. INTERVENTION: The VR group performed exergames using Kinect, while the control group accomplished conventional balance exercises. Both groups received 18 training sessions for 6 weeks. MAIN OUTCOME MEASURES: Limits of stability, timed Up and Go (TUG) test, and 10-m walk tests with and without cognitive task and their dual-task costs (DTCs), Berg Balance Scale, Multiple Sclerosis Walking Scale-12, Fall Efficacy Scale-International, Activities-specific Balance Confidence Scale, and fall history were obtained pre- and post intervention and after a 3-month follow-up. RESULTS: At both post intervention and follow-up, TUGcognitive and DTCs on the TUG were significantly lower and the 10-m walkcognitive was significantly higher in the VR group. At follow-up, reaction time and the number of falls demonstrated significant differences favoring the VR group, whereas the directional control revealed significant difference in favor of the control group (P<.05). The other outcomes showed no statistically significant difference at post intervention or follow-up. CONCLUSIONS: Both the VR-based and conventional balance exercises improved balance and mobility in PwMS, while each acted better in improving certain aspects. VR-based training was more efficacious in enhancing cognitive-motor function and reducing falls, whereas conventional exercises led to better directional control. Further studies are needed to confirm the effectiveness of recruiting VR-based exercises in clinical settings.

The effect of transcranial direct current stimulation on balance in healthy young and older adults: A systematic review of the literature.

Various studies have investigated the effect of noninvasive brain stimulation methods such as transcranial direct stimulation (tDCS) on postural control in healthy young and older adults. However, the use of different treatment protocols and outcome measures makes it difficult to interpret the research results. This systematic review provides a comprehensive overview of the current literature on the effect of tDCS on postural control. Nine databases were searched for papers assessing the effect of tDCS on postural control in young healthy and/or older adults. The data of included studies were extracted and methodological quality examined using PEDro. Sixteen studies met the inclusion criteria. The results showed that anodal tDCS (a-tDCS) of primary motor cortex may improve dynamic balance in young healthy individuals. In older adults, a-tDCS of dorsolateral prefrontal cortex and cerebellum showed a positive effect on dual task and dynamic balance, respectively. In conclusion, tDCS may improve both static and dynamic balance in younger and older adults. However, due to lack of consensus in the results, caution is required when drawing conclusions with regards to these findings.

Responsiveness of a Persian version of Knee Injury and Osteoarthritis Outcome Score and Tegner activity scale in athletes with anterior cruciate ligament reconstruction following physiotherapy treatment.

PURPOSE: To evaluate the responsiveness and determine the minimal clinically important changes (MCICs), anchored by the patient response to a 7-point global rating scale, for Knee Injury and Osteoarthritis Outcome Score (KOOS), and Tegner activity scale in athletes undergoing physiotherapy treatment after anterior cruciate ligament reconstruction (ACL-R). Methods: Fifty-four patients undergoing physiotherapy completed the Persian versions of KOOS and Tegner scales at weeks 6 and 10 post ACL-R. The 7-point global rating of change was also completed at week 10. Responsiveness was calculated via receiver operating characteristic curve and correlation analysis. Results: Acceptable responsiveness was reached by the KOOS sports and recreation subscale (Sport/Rec) (area under the curve (AUC) = 0.72; Gamma = 0.37) and Tegner scale (AUC = 0.75; Gamma = 0.59). The MCIC scores of KOOS subscales and Tegner scale were reported. Conclusion: Our findings demonstrated that the KOOS Sport/Rec subscale and Tegner scale have adequate responsiveness between weeks 6 and 10 of physiotherapy. Therefore, these scales should be used to evaluate the effects of physiotherapy treatment and the changes in activity levels in this population. The MCIC scores of the KOOS and Tegner scale can be used to detect changes significant to the patient while avoiding limitations of other methods.

Impaired local dynamic stability during treadmill walking predicts future falls in patients with multiple sclerosis: A prospective cohort study.

BACKGROUND: Falling is a significant problem in patients with multiple sclerosis (MS) and the majority of falls occur during dynamic activities. Recently, there have been evidences focusing on falls and local stability of walking based on dynamic system theory in the elderly as well as patients with cerebral concussion. However, in patient with MS, this relationship has not been fully investigated. The aim of this study was to investigate local stability of walking as a risk factor for falling in patients with MS. METHODS: Seventy patients were assessed while walking at their preferred speed on a treadmill under single and dual task conditions. A cognitive task (backward counting) was used to assess the importance of dual tasking to fall risk. Trunk kinematics were collected using a cluster marker over the level of T7 and a 7-camera motion capture system. To quantify local stability of walking, maximal finite-time Lyapunov exponent was calculated from a 12-dimensional state space reconstruction based on 3-dimensional trunk linear and angular velocity time series. Participants were classified as fallers (≥1) and non-fallers based on their prospective fall occurrence. FINDINGS: 30 (43%) participants recorded ≥1 falls and were classified as fallers. The results of multiple logistic regression analysis revealed that short-term local dynamic stability in the single task condition (P<0.05, odds ratio=2.214 (1.037-4.726)) was the significant fall predictor. INTERPRETATION: The results may indicate that the assessment of local stability of walking can identify patients who would benefit from gait retraining and fall prevention programs.

Differences in timing and magnitude of lumbopelvic rotation during active and passive knee extension in sitting position in people with and without low back pain: A cross-sectional study.

Repetitive lumbopelvic rotation (LPR) during active limb movements has been indicated as a factor that contributes to low back pain (LBP). Prior studies suggest that people with LBP demonstrate greater and earlier LPR during limb movements in prone. We examined timing and magnitude of LPR during sitting active knee extension in people with and without LBP. We also investigated differences of LPR during active and passive knee extension in LBP group. 38 men (mean age: 38.4)10.6) years) with chronic mechanical LBP and 38 matched healthy men (mean age: 36.6(8.4) years) were examined. Kinematic data were collected by motion capture system and analyzed using OpenSim software. The difference between the start time of knee extension and start time of LPR was calculated and was normalized to knee extension movement time. Maximum angular displacement for LPR was also calculated across time. People with LBP demonstrated earlier LPR during knee extension than healthy subjects (P < 0.01). There was, however, no difference in maximum LPR between groups. LBP group also demonstrated greater and earlier LPR during active than during passive knee extension (P < 0.01). Earlier LPR during limb movements in sitting may be related to LBP. Quadriceps muscle activity and inefficient trunk muscles activation may contribute to early LPR in LBP group. A greater understanding of the factors that may contribute to early LPR during daily activities can provide information to guide rehabilitation treatment for people with LBP.

Examination of Lumbopelvic and Lower Extremity Movements in two Subgroups of People with Chronic Low Back Pain Based on the Movement System Impairment Model During a Stair Descending Task.

BACKGROUND: Excessive and early lumbopelvic motion during functional tasks is associated with increased pain and symptoms in people with low back pain. The purpose of the current study was to compare lumbopelvic and lower extremity movements in two subgroups of chronic low back pain sufferers and healthy subjects during a stair descending task based on a movement system impairment model. MATERIAL AND METHODS: A clinical examination was conducted to assign people with low back pain to movement system impairment-based subgroups. A control group included 18 healthy subjects, a lumbar Rotation with Flexion group included 12 subjects, and a lumbar Rotation with Extension group included 16 subjects. Differences in kinematics data between the groups were recorded during a stair descending task using a 7-camera 3-dimensional motion capture system. RESULTS: In the lumbar Rotation with Flexion group, the onset of lumbar movement occurred earlier than in the control group (p = 0.043). In the lumbar Rotation with Flexion group, axial and frontal plane rotation of the pelvis and lower extremity were significantly greater than in the control group. Mean differences between the lumbar Rotation with Extension and control group were minimal for the motion assessed. CONCLUSION: Early and excessive lumbopelvic movement and more axial rotation in the lower extremities during a stair descending task were found in the lumbar Rotation with Flexion subgroup, which can be an important factor contributing to the development or persistence of low back pain in this group.

Muscle Activity Pattern Dysfunction During Sit to Stand and Stand to Sit in the Movement System Impairment Subgroups of Low Back Pain.

OBJECTIVE: To investigate impairment in the activity pattern of some muscles involved in sit to stand (STD) and stand to sit (STS) among 2 low back pain (LBP) subgroups of the Movement System Impairment (MSI) model. DESIGN: Case-control study. SETTING: A university medical center. PARTICIPANTS: Fifteen women without chronic LBP and 22 women with chronic LBP (N=37) in 2 subgroups (15 into the lumbar extension rotation (LER) and 7 into lumbar flexion rotation [LFR]) voluntarily participated in this study. INTERVENTIONS: Participants were asked to perform STD and STS at a preferred speed. Surface electromyography (EMG) were measured bilaterally from the internal oblique (IO), lumbar erector spine (ES), medial hamstring (MH), and lateral hamstring (LH) muscles. MAIN OUTCOME MEASURES: Changes in mean and maximum amplitude, time to peak amplitude, duration of muscle activity, and bilateral asymmetry of these variables. RESULTS: During STD, bilateral asymmetry in mean amplitude of MH in the LER subgroup (P=.031) and bilateral asymmetry in duration of LH in the LFR subgroup (P=.026) were exhibited. Also, in this task reduced time to peak left MH activation were found in the LFR subgroup than 2 other groups (control; P=.028/LER; P=.004). During STS, increased left ES maximum amplitude were observed in the LFR subgroup than LER subgroup (P=.029). Also, reduced time to peak right ES (P=.035) and left LH (P=.038) activation in the LER subgroup than control subjects and reduced time to peak left LH activation in LFR subgroup than control subjects (P=.041) were observed during STS. CONCLUSIONS: The differences between the 2 LBP subgroups may be a result of impairment in the activity pattern of some muscles during functional activity.