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.

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.

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.

Validity and reliability of Persian version of the Specific Nordic questionnaire in Iranian industrial workers.

BACKGROUND: Nordic is one of the most popular questionnaires for evaluating Work-related Musculoskeletal Disorders (WMSDs), but no studies have been reported on the reliability and validity of this questionnaire in Iran. OBJECTIVE: The aim of this study was translation, cross-cultural adaptation and validation of the Persian version of the Specific Nordic questionnaire (SNQ), and evaluation of the reliability of this questionnaire for the assessment of WMSDs in Iranian industrial workers. METHODS: The SNQ was completed by 122 Iranian industrial workers with lumbar or knee musculoskeletal disorders to assess the reliability and construct validity. The validity was assessed by knee injury and Osteoarthritis Outcome Score (KOOS) and Oswestry Disability Index (ODI) questionnaires. Reliability was assessed by a test-retest procedure for 60 patients with 7-days interval. RESULTS: There was significant positive correlation between KSNQ and KOOS pain (r = 0.71, p < 0.05) and the KSNQ and KOOS QOL (r = 0.72, p < 0.05). There was High Pearson correlation between LSNQ and ODI (r = 0.77, p < 0.05). Both lumbar and knee SNQ had a high Kappa coefficient correlation (0.83-1 for KSNQ and 0.63-1 for LSNQ). CONCLUSIONS: The Persian version of the SNQ is a reliable and valid instrument to be used for the assessment of WMSDs in Iranian industrial workers.

Posture-cognition interaction during quiet standing in patients with knee osteoarthritis.

The aim of this study was to determine the effects of cognitive task (silent backward counting) on postural control in patients with knee osteoarthritis (OA) (n = 25) as compared with asymptomatic controls (n = 25). Static postural control during quiet standing was assessed under different conditions including: (1) rigid surface-open eyes; (2) rigid surface-closed eyes; (3) foam surface-open eyes; and (4) foam surface-closed eyes. Dependent variables were center of pressure (COP) parameters and cognitive score. The results of this study showed that for most COP parameters, the patients with knee OA had greater postural sway than asymptomatic control subjects. Moreover, while cognitive loading affects postural sway in dual-task compared to single-task conditions, the pattern of change was not different between the two groups. Cognitive loading caused decreased postural sway in both groups. Future studies should select patients with more disability, choose more attention demanding cognitive tasks, and expose the subjects to dynamic balance situations to further explore the effect of cognitive loading on postural performance in this specific patient population.

Correlation between Hip Rotation Range-of-Motion Impairment and Low Back Pain. A Literature Review.

BACKGROUND: Hip rotation range-of-motion (ROM) impairment has been proposed as a contributing mechanical factor in the development of low back pain (LBP) symptoms. There is a hypothesis which suggests that a limited range of hip rotation results in compensatory lumbar spine rotation. Hence, LBP may develop as the result. This article reviews studies assessing hip rotation ROM impairment in the LBP population. MATERIAL AND METHODS: The MEDLINE and EMBASE databases were searched without time restriction. Two authors independently selected related articles using the same search strategy and key words. RESULTS: Among 124 articles 12 met the review inclusion criteria. The results of the studies are assessed in three sections, investigating the relationship between low back pain and 1) hip internal rotation ROM, 2) hip external rotation ROM and 3) hip total rotation ROM. Asymmetrical (right versus left, lead versus non-lead) and limited hip internal rotation ROM were common findings in patients with LBP. Reduced and asymmetrical total hip rotation was also observed in patients with LBP. However, none of the studies explicitly reported limited hip external rotation ROM. CONCLUSION: The precise assessment of hip rotation ROM, especially hip internal rotation ROM, must be included in the examination of patients with LBP symptoms.

Evaluation of differences between two groups of low back pain patients with and without rotational demand activities based on hip and lumbopelvic movement patterns.

BACKGROUND: Excessive and earlier lumbopelvic motions during trunk and limb movements tests have been reported in both low back pain (LBP) patients with and without trunk and hip rotational demand activities. The aim of the present study was to determine differences in hip and lumbopelvic rotation during the active hip internal rotation (AHIR) test between two groups of LBP patients with and without regular trunk and hip rotational demand activities. MATERIAL AND METHODS: A total of 35 LBP patients, including 15 males who regularly participated in rotational demand sports activities and 20 males not participating in sports and functional rotational demand activities, participated in study. The AHIR test was performed. The kinematic variables of hip and pelvic rotations were recorded by a Qualisys motion analysis system. Pelvic and hip rotations were calculated across time during the test. In addition, pelvic rotations in the first half of the test and pelvic-hip timing were calculated. RESULTS: People with rotational demand activities had a higher pelvic rotation both during the test and in the first 50% of movement. Earlier pelvic rotation was observed in people with rotational demand activities compared to people with non-rotational demand activities. CONCLUSION: 1. The data of the current study suggests that lumbopelvic movement patterns in different groups of LBP patients in regard to their specific activities may vary. 2. LBP people with rotational demand sports activities have a greater tendency of pelvic rotation motion during the AHIR.