Peak sagittal plane spine kinematics in female gymnasts with and without a history of low back pain

BackgroundFemale gymnasts have a greater prevalence of back pain compared to other female athletes. There is little evidence that female artistic gymnasts with and without back pain demonstrate different movement patterns during gymnastics skills. The purpose of this study was to determine if there were differences in back movements during back walkovers and back handsprings among female artistic gymnasts.MethodsFemale artistic gymnasts (8–18 years old) with and without back pain wore inertial sensors on their torso, arms, and legs while performing back walkovers (N = 14) and back handsprings (N = 15) on the floor and balance beam at their training gymnastics facilities.FindingsGymnasts with back pain had similar spine peak extension, peak flexion, and range of motion during back walkovers and back handsprings compared to gymnasts without back pain. Additionally, no differences in sagittal plane spine kinematics were found between the groups at any specific time point during either the back walkover or back handspring skills. However, a large portion of the data collected was excluded during quality assurance, thus our final sample sizes are small.InterpretationThese findings suggest that gymnasts with back pain have similar sagittal plane movements to those without back pain. The relationship between back pain and gymnastics training load/intensity is currently unclear. We suggest future studies to investigate common artistic gymnastics skills and back pain prevalence with more participants, full-body motion analysis with kinetic measurement capabilities, and longitudinally for those demonstrating back pain.     

Effect of 2 lumbar spine postures on transversus abdominis muscle thickness during a voluntary contraction in people with and without low back pain

Objective

The present study investigated the effect of 2 different lumbar spine postures, neutral and flexed lumbar postures, on transversus abdominis (TrA) muscle function during a voluntary contraction (hollowing and draw-in maneuver) in people with and without low back pain (LBP).

Methods

Thirty participants with LBP and 30 healthy participants were recruited for this cross-sectional study. Transversus abdominis muscle function was measured as a change in thickness with ultrasound imaging. Participants performed voluntary TrA contraction in a supine lying position with the lumbar spine in neutral and flexed postures. Data were analyzed using a 2-way (groups, postures) analysis of variance.

Results

Lumbar posture influenced TrA function during a voluntary contraction in people with and without LBP. There was a significant main effect of posture (F_1,58 = 16.140, P < .001). Neutral lumbar posture improved participants' ability to recruit TrA in both group (mean difference, 7.5%; 95% confidence interval, 3.8%-11.3%). No significant differences were found between healthy subjects and those with LBP.

Conclusions

The results of the present study showed that, in subjects performing a voluntary TrA contraction, the neutral lumbar posture improves the ability to increase change in TrA thickness. This study found no significant difference in TrA thickness change between healthy subjects and those with nonspecific LBP.     

Muscle activation patterns in subjects with and without low back pain

OBJECTIVE: To analyze muscle activation patterns during various footplate perturbations, used as proprioceptive challenges in patients with low back pain (LBP) and in controls. DESIGN: A prospective and controlled comparative study. SETTING: Outpatient clinic. PARTICIPANTS: Twenty subjects with chronic LBP and 20 age- and sex-matched controls. INTERVENTIONS: The subjects underwent 5 sets of footplate perturbations in 3 directions with 16 perturbations for each set. MAIN OUTCOME MEASURES: Latency, frequency, and asymmetry of muscle activation of the erector spinae, rectus abdominus, anterior tibialis, and gastrocnemius muscles were measured bilaterally with surface electromyography. RESULTS: In the toes-up movements, subjects with LBP were significantly less likely to activate their rectus abdominus muscles (P=.02), and they were more likely to exhibit asymmetric muscle activation in the smaller forward movements (odds ratio=4.1, P=.03). The latter result appears to be driven by asymmetric contraction of the erector spinae and rectus abdominus. CONCLUSIONS: Significantly more subjects with LBP than control subjects exhibited absent firing of trunk muscles during 2 of the 5 footplate perturbations. These results suggest an abnormality of the neuromuscular loop and may represent altered proprioception.     

Automatic activity of deep and superficial abdominal muscles during stable and unstable sitting positions in individuals with chronic low back pain

Objective

The purpose of this study was to assess muscle thickness changes in the deep and superficial abdominal muscles, during sitting on stable and unstable surfaces in subjects with and without chronic low back pain (CLBP).

The relationship between work function and low back pain history in occupationally active individuals

PURPOSE: To investigate the relationship between work function and low back pain (LBP) history. STUDY DESIGN: Cross-sectional study. BACKGROUND: In some countries, traditional medical examinations do not assess work performance in people who continue working despite a history of LBP, although such assessment may be required. METHODS: A total of 100 industrial metal workers were assigned to groups with and without LBP history. Logistic regression and t-tests examined the associations between physical work performance (represented by dynamic strength evaluation) and the group, and compared worker performance between the two groups. Similar tests examined potentially confounding effects on group assignment. RESULTS: Work performance was significantly associated with the group in dynamic strength sub-tests assessing weight lifting and carrying. The weights handled were lower in the group with LBP history (p < 0.05). Only the workers' country of origin affected group assignment; adjustment for this factor, as well as for age and education improved the associations between work performance and the group. CONCLUSIONS: Workers with a history of LBP display decreased physical performance at work, which should be subject to further research and treated as a health-related problem in accordance with the ICF model.     

The relationship between work function and low back pain history in occupationally active individuals

Purpose.?To investigate the relationship between work function and low back pain (LBP) history.

Study design.?Cross-sectional study.

Background.?In some countries, traditional medical examinations do not assess work performance in people who continue working despite a history of LBP, although such assessment may be required.

Methods.?A total of 100 industrial metal workers were assigned to groups with and without LBP history. Logistic regression and t-tests examined the associations between physical work performance (represented by dynamic strength evaluation) and the group, and compared worker performance between the two groups. Similar tests examined potentially confounding effects on group assignment.

Results.?Work performance was significantly associated with the group in dynamic strength sub-tests assessing weight lifting and carrying. The weights handled were lower in the group with LBP history (p < 0.05). Only the workers' country of origin affected group assignment; adjustment for this factor, as well as for age and education improved the associations between work performance and the group.

Conclusions.?Workers with a history of LBP display decreased physical performance at work, which should be subject to further research and treated as a health-related problem in accordance with the ICF model.     

The relationship between psychological distress and free-living physical activity in individuals with chronic low back pain

The aim of this cross-sectional pilot-study was to investigate the relationship between psychological distress and free-living physical activity (PA) in individuals with chronic low back pain (CLBP). Thirty-eight participants with non-specific CLBP (29 = distressed; 9 = non-distressed) were recruited. PA levels were measured using an accelerometer (activPAL? activity monitor) over a one week period. The following parameters of physical activity were recorded: time upright (standing or walking), time standing, time walking, and step count. Psychological distress was assessed using a modified version of the distress risk assessment method (DRAM) which is a combination of somatic anxiety and depressive symptoms. The Distressed group spent significantly less time upright over a mean 24 h day (?1.47 h, 95% CI ?2.70 to ?0.23 h, p < 0.05), attributable to 1.01 h less standing and 0.46 h less walking. Depressive symptoms were a statistically significant independent predictor of time upright (β = ?0.49, p < 0.05). This pilot-study found that individuals with CLBP and elevated levels of distress spend less time upright than their non-distressed counterparts. Clinically, when treating individuals with CLBP and elevated distress levels, free-living PA may be low and interventions aimed at increasing upright activity may be appropriate.     

Ultrasound measurement of deep abdominal muscle activity in sitting positions with different stability levels in subjects with and without chronic low back pain

The purpose of this study was to investigate the changes in the thickness of the transversus abdominis (TrA) and internal oblique (IO) muscles in three sitting postures with different levels of stability. The technique of ultrasound imaging was used for individuals with and without chronic low back pain (LBP). A sample of 40 people participated in this study. Subjects were categorised into two groups: with LBP (N = 20) and without LBP (N = 20). Changes in the thickness of tested muscles were normalized under three different sitting postures to actual muscle thickness at rest in the supine lying position and were expressed as a percentage of thickness change. The percentage of thickness change in TrA and IO increased as the stability of the sitting position decreased in both groups. However, the percentages of thickness change in all positions were less in subjects with LBP. There was a significant difference in thickness change in TrA when sitting on a gym ball between subjects with and without LBP but no difference was found when sitting on a chair. There was no significant difference in thickness change in IO in all positions between the two groups. Our findings indicate that difference in the percentage of thickness change in TrA between subjects with and without LBP increases as the stability of sitting position decreases.     

Muscle activation timing and balance response in chronic lower back pain patients with associated radiculopathy

BackgroundPatients with chronic low back pain and associated radiculopathy present with neuromuscular symptoms both in their lower back and down their leg; however, investigations of muscle activation have so far been isolated to the lower back. During balance perturbations, it is necessary that lower limb muscles activate with proper timing and sequencing along with the lower back musculature to efficiently regain balance control.MethodsPatients with chronic low back pain and radiculopathy and matched controls completed a series of balance perturbations (rapid bilateral arm raise, unanticipated and anticipated sudden loading, and rapid rise to toe). Muscle activation timing and sequencing as well as kinetic response to the perturbations were analyzed.FindingsPatients had significantly delayed lower limb muscle activation in rapid arm raise trials as compared to controls. In sudden loading trials, muscle activation timing was not delayed in patients; however, some differences in posterior chain muscle activation sequencing were present. Patients demonstrated less anterior–posterior movement in unanticipated sudden loading trials, and greater medial–lateral movement in rise to toe trials.InterpretationPatients with low back pain and radiculopathy demonstrated some significant differences from control participants in terms of muscle activation timing, sequencing, and overall balance control. The presence of differences between patients and controls, specifically in the lower limb, indicates that radiculopathy may play a role in altering balance control in these patients.     

Reduced task-induced variations in the distribution of activity across back muscle regions in individuals with low back pain

This study investigated change in the distribution of lumbar erector spinae muscle activity and pressure pain sensitivity across the low back in individuals with low back pain (LBP) and healthy controls. Surface electromyographic (EMG) signals were recorded from multiple locations over the lumbar erector spinae muscle with a 13 × 5 grid of electrodes from 19 people with chronic nonspecific LBP and 17 control subjects as they performed a repetitive lifting task. The EMG root mean square (RMS) was computed for each location of the grid to form a map of the EMG amplitude distribution. Pressure pain thresholds (PPT) were recorded before and after the lifting task over a similar area of the back. For the control subjects, the EMG RMS progressively increased more in the caudal region of the lumbar erector spinae during the repetitive task, resulting in a shift in the distribution of muscle activity. In contrast, the distribution of muscle activity remained unaltered in the LBP group despite an overall increase in EMG amplitude. PPT was lower in the LBP group after completion of the repetitive task compared to baseline (average across all locations: pre: 268.0 ± 165.9 kPa; post: 242.0 ± 166.7 kPa), whereas no change in PPT over time was observed for the control group (320.1 ± 162.1 kPa; post: 322.0 ± 179.5 kPa). The results demonstrate that LBP alters the normal adaptation of lumbar erector spinae muscle activity to exercise, which occurs in the presence of exercise-induced hyperalgesia. Reduced variability of muscle activity may have important implications for the provocation and recurrence of LBP due to repetitive tasks.     

Spatial distribution of lumbar erector spinae muscle activity in individuals with and without chronic low back pain during a dynamic isokinetic fatiguing task

BackgroundIndividuals with chronic low back pain (CLBP) commonly present with increased trunk muscle fatigability; typically assessed as reduced time to task failure during non-functional isometric contractions. Less is known about the specific neuromuscular responses of individuals with CLBP during dynamic fatiguing tasks. We investigate the regional alteration in muscle activation and peak torque exertion during a dynamic isokinetic fatiguing task in individuals with and without CLBP.MethodsElectromyography (EMG) was acquired from the lumbar erector spinae unilaterally of 11 asymptomatic controls and 12 individuals with CLBP, using high-density EMG (13 × 5 grid of electrodes). Seated in an isokinetic dynamometer, participants performed continuous cyclic trunk flexion-extension at 60^o/s until volitional exhaustion.FindingsSimilar levels of muscle activation and number of repetitions were observed for both groups (p > 0.05). However, the CLBP group exerted lower levels of peak torque for both flexion and extension moments (p < 0.05). The centre of lumbar erector spinae activity was shifted cranially in the CLBP group throughout the task (p < 0.05), while the control participants showed a more homogenous distribution of muscle activity.InterpretationPeople with CLBP displayed altered and potentially less efficient activation of their lumbar erector spinae during a dynamic fatiguing task. Future studies should consider using high-density EMG biofeedback to optimise the spatial activation of the paraspinal musculature in people with low back pain (LBP).     

Effect of increased relative stiffness of the lumbar spine on hamstring muscle stretching in individuals with a history of low back pain suspected to have a clinical lumbar instability: A randomized crossover design

BackgroundTheoretically, lumbopelvic stabilization techniques during hamstring muscle stretching could increase lumbar stiffness relative to hamstring muscle in individuals with a history of low back pain and suspected clinical lumbar instability. However, evidence to support this theory is limited. This study aimed to 1) determine changes in lumbopelvic, lumbar, and hip motions, and hamstring muscle length after stretching exercises with lumbopelvic stiffening or relaxing techniques, and 2) compare those changes between techniques.MethodsThis study used a randomized crossover design. Thirty-two participants with a history of low back pain and bilateral hamstring muscle tightness were recruited. The order of the first technique was randomly assigned. After a 2-day washout, participants were crossed over to the second technique. Motion data during active forward trunk bending and bilateral hamstring muscle length during passive knee extension were collected pre- and post-intervention.FindingsSignificant increases (P < 0.05) were found in bilateral hamstring muscle length for both techniques. However, stiffening technique demonstrated a significant decrease in lumbar motion (P < 0.05) and increase in hip motion (P < 0.05), while relaxing technique demonstrated trends showing increases in lumbar and hip motions (P = 0.134 and 0.115, respectively). The findings showed significantly greater improvement (P < 0.05) in lumbar and hip motions with stiffening technique.InterpretationThe findings suggest increased relative stiffness of the lumbar spine during hamstring muscle stretching can specifically lengthen bilateral hamstring muscle and decrease excessive lumbar motion. This stiffening technique may prevent excessive movement of the lumbar spine, thereby reducing the risk of recurrent low back pain.     

慢性腰痛患者在脊柱突然失衡时多裂肌的肌电表现

目的：研究多裂肌在维持腰椎稳定中的作用及其与慢性腰痛的关系。方法：腰痛组为慢性腰痛病人15例，男8例，女7例，平均年龄33．53岁。正常组为无腰痛病史的健康志愿者15例，年龄、性别与腰痛组相匹配。运用表面电极记录上肢快速前屈、外展、后伸时多裂肌、最长肌、腰髂肋肌及三角肌的肌电信号，对各椎旁肌收缩的潜伏期与三角肌收缩的潜伏期之差值作比较。结果：正常组多裂肌在上肢三个方向的运动中收缩均早于最长肌、腰髂肋肌；腰痛组各椎旁肌几乎同时收缩，多裂肌在上肢三个方向的运动中均较正常人收缩延迟。结论：椎旁肌群中多裂肌在腰椎稳定中发挥重要作用，慢性腰痛病人多裂肌功能减退。     

Factors related to the inability of individuals with low back pain to improve with a spinal manipulation

BACKGROUND AND PURPOSE: Although spinal manipulation is one of the few interventions for low back pain supported by evidence, it appears to be underutilized by physical therapists, possibly due to therapists' concerns that a patient may not benefit from the intervention. The purpose of this study was to identify factors that are associated with an inability to benefit from manipulation. SUBJECTS: Seventy-five people with nonradicular low back pain (mean age=37.6 years, SD=10.6, range=19-59; mean duration of symptoms=41.7 days, SD=54.7, range=1-252) participated. METHODS: Subjects underwent a standardized examination that included history-taking; self-reports of pain, disability, and fear-avoidance beliefs; measurement of lumbar and hip range of motion; and use of various tests. All subjects received a spinal manipulation intervention for a maximum of 2 sessions. Subjects who did not show greater than 5 points of improvement on the modified Oswestry Low Back Pain Disability Questionnaire were considered to have shown no improvement with the manipulation. Baseline variables were tested for univariate relationship with the outcome of the manipulation. Variables showing a univariate relationship were entered into a logistic regression equation, and adjusted odds ratios were calculated. RESULTS: Twenty subjects (28%) did not improve with manipulation. Six variables were identified as being related to inability to improve with manipulation: longer symptom duration, having symptoms in the buttock or leg, absence of lumbar hypomobility, less hip rotation range of motion, less discrepancy in left-to-right hip medial rotation range of motion, and a negative Gaenslen sign. The resulting logistic regression model explained 63% of the variance in manipulation outcome. DISCUSSION AND CONCLUSION: The majority of subjects improved with manipulation. Baseline variables could be identified that were predictive of which subjects would not improve.     

Differences in the kinematics of the cervical and thoracic spine during functional movement in individuals with or without chronic neck pain: a systematic review

BackgroundChronic neck pain is common, impacting a person’s ability to complete functional tasks. One method of quantifying functional movement is three dimensional (3D) motion analysis, however, it is unknown whether it may detect alterations in movement kinematics in individuals with neck pain.ObjectiveTo systematically review studies to determine possible differences in cervical and thoracic kinematics during functional movement as measured by 3D motion analysis in individuals with neck pain compared to controls.Data sourcesMedline, Amed, Scopus, Cochrane, Embase, CINAHL searched on 11/11/2017.Study selectionStudies reported 3D kinematics of functional movement (based on real-world situational biomechanics, i.e., multi-planar movements) of the cervical and thoracic spine in individuals with and without neck pain.Study appraisal and synthesisTwo reviewers assessed study quality; studies were summarised using discussion.ResultsFour thousand four hundred and sixteen title/abstracts were screened, 11 full texts retrieved. Common reasons for exclusion were participants ≤8 years of age and studies that did not investigate functional movement. Included studies (n = 5) used 3D motion analysis to assess kinematics during functional tasks including typing, gaming and resting posture. Participants with neck pain displayed greater neck flexion postures, reduced head velocity and smoothness of movement.LimitationsVariations in measurement methods and participant samples prevented meta-analysis.ConclusionThough few studies were identified, altered kinematics were observed in individuals with neck pain, suggesting further research examining cervical spine kinematics is warranted. Recognising kinematic differences is important for clinicians to identify possible movement risk factors in individuals with neck pain that may be targeted with treatment.Systematic review registration number PROSPEROCRD42017076053.     

A behavioral treatment for sitting and standing intolerance in a patient with chronic low back pain

This study reports on the effectiveness of an individualized shaping treatment program for sitting and standing intolerance in a patient with chronic low back pain following a laminectomy for removal of an intradural tumor. Functional assessment of sitting and standing tolerance, observation of pain behaviors, and a self-report measure regarding the pain experience were carried out during baseline, treatment, posttreatment, and at a 6-month follow-up. By the end of the 6-week inpatient treatment, the patient was able to stand still for 25 min and to sit for 15 min. The overall pain behavior diminished significantly. These findings underscore the importance of relatively simple and cost-effective individualized behavioral programs for chronic pain patients.     

Effects of a Pilates protocol in individuals with non-specific low back pain compared with healthy individuals: Clinical and electromyographic analysis

BackgroundElectromyography may be useful for assessing and understanding trunk muscle activation, and Pilates is commonly used as a treatment for low back pain. The objective of this study was to verify electromyography of trunk muscles after a Pilates protocol in individuals with non-specific low back pain and in healthy individuals.MethodsVolunteers were divided into two groups: non-specific low back pain (n = 19) and clinically healthy (n = 16) groups. Clinical assessments, classification of patients into subgroups, electromyography evaluations of the right lumbar extensor and right transverse abdominal/internal oblique muscle of the abdomen were performed before and after an 8-week Pilates protocol.FindingsComparisons were made before and after the protocol and with the control group. There was significant improvement in pain, flexibility, resistance and strength of trunk muscles. In addition, after the Pilates, there was a decrease in the time elapsed between the onset and peak of lumbar muscle activation during the evaluation of trunk extension in the low back pain group, coming closer to the time of the abdominal muscle, as it also occurred in the control group.InterpretationPilates caused clinical improvement and balanced trunk muscle activation in the low back group, becoming similar to that of the control group. Furthermore, the effects of the proposed protocol were the same between the groups. Thus, Pilates may be indicated for management of non-specific low back pain.