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Journal of Biomechanics Mar 2023Musculoskeletal disorders affecting the back are highly prevalent in fields of occupation involving repetitive lifting and working in forward leaning postures....
Musculoskeletal disorders affecting the back are highly prevalent in fields of occupation involving repetitive lifting and working in forward leaning postures. Back-support exoskeletons are developed to relieve workers in physically demanding occupations. This study investigates the physiological effects of a lightweight exoskeleton which provides support through textile springs worn on the back. We hypothesized that wearing such a passive back-support exoskeleton reduces muscle activity of the back and hip muscles, while not influencing abdominal muscle activity and movement kinematics during typical occupational tasks. We collected electromyography data from the main back and hip muscles as well as whole body kinematics data via optical motion tracking during a set of relevant weight lifting tasks corresponding to typical work conditions. In our sample of 30 healthy volunteers, wearing the exoskeleton significantly reduced muscle activity, with reductions up to 25.59% during forward leaning and 20.52% during lifting in the main back and hip muscles (Erector Spinae at thoracic and lumbar level and Quadratus Lumborum). Simultaneously, no changes in knee and hip range of motion were observed. The stretch of the textile springs correlated with the body mass index and chest circumference of the wearer, and depended on posture, but not on the lifted load. The LiftSuit exoskeleton relieved back and hip muscles during typically straining occupational tasks, while biomechanical parameters were preserved. This suggests that passive lift-support exoskeletons can be safely used to relieve workers during lifting and forward leaning tasks.
Topics: Humans; Exoskeleton Device; Lifting; Muscle, Skeletal; Back Muscles; Electromyography; Posture; Lumbosacral Region; Biomechanical Phenomena
PubMed: 36806003
DOI: 10.1016/j.jbiomech.2023.111489 -
BMC Musculoskeletal Disorders Apr 2017Impaired lumbo-pelvic movement in people with low back pain during bending task has been reported previously. However, the regional mobility and the pattern of the...
BACKGROUND
Impaired lumbo-pelvic movement in people with low back pain during bending task has been reported previously. However, the regional mobility and the pattern of the lumbo-pelvic movement were found to vary across studies. The inconsistency of the findings may partly be related to variations in the speed at which the task was executed. This study examined the effects of bending speeds on the kinematics and the coordination lumbo-pelvic movement during forward bending, and to compare the performance of individuals with and without low back pain.
METHODS
The angular displacement, velocity and acceleration of the lumbo-pelvic movement during the repeated forward bending executed at five selected speeds were acquired using the three dimensional motion tracking system in seventeen males with low back pain and eighteen males who were asymptomatic. The regional kinematics and the degree of coordination of the lumbo-pelvic movement during bending was compared and analysed between two groups.
RESULTS
Significantly compromised performance in velocity and acceleration of the lumbar spine and hip joint during bending task at various speed levels was shown in back pain group (p < 0.01). Both groups displayed a high degree of coordination of the lumbo-pelvic displacement during forward bending executed across the five levels of speed examined. Significant between-group difference was revealed in the coordination of the lumbo-pelvic velocity and acceleration (p < 0.01). Asymptomatic group moved with a progressively higher degree of lumbo-pelvic coordination for velocity and acceleration while the back pain group adopted a uniform lumbo-pelvic pattern across all the speed levels examined.
CONCLUSIONS
The present findings show that bending speed imposes different levels of demand on the kinematics and pattern of the lumbo-pelvic movement. The ability to regulate the lumbo-pelvic movement pattern during the bending task that executed at various speed levels was shown only in pain-free individuals but not in those with low back pain. Individuals with low back pain moved with a stereotyped strategy at their lumbar spine and hip joints. This specific aberrant lumbo-pelvic movement pattern may have a crucial role in the maintenance of the chronicity in back pain.
Topics: Adult; Biomechanical Phenomena; Humans; Low Back Pain; Lumbosacral Region; Male; Movement; Range of Motion, Articular; Young Adult
PubMed: 28415980
DOI: 10.1186/s12891-017-1515-3 -
Pain Physician Jan 2024Chronic low back pain is one of the most common causes of disability, affecting more than 600 million people worldwide with major social and economic costs. Current... (Randomized Controlled Trial)
Randomized Controlled Trial
The Safety and Effectiveness of Orthobiologic Injections for Discogenic Chronic Low Back Pain: A Multicenter Prospective, Crossover, Randomized Controlled Trial with 12 Months Follow-up.
BACKGROUND
Chronic low back pain is one of the most common causes of disability, affecting more than 600 million people worldwide with major social and economic costs. Current treatment options include conservative, surgical, and minimally invasive interventional treatment approaches. Novel therapeutic treatment options continue to develop, targeting the biological cascades involved in the degenerative processes to prevent invasive spinal surgical procedures. Both intradiscal platelet-rich plasma (PRP) and bone marrow concentrate (BMC) applications have been introduced as promising regenerative treatment procedures.
OBJECTIVES
The primary objective of this study is to assess the safety and effectiveness of an orthobiologic intradiscal injection, PRP or BMC, when compared to control patients. The secondary objectives are to measure: patient satisfaction and incidence of hospitalization, emergency room visit and spine surgery at predetermined follow-up intervals.
STUDY DESIGN
A multicenter, prospective, crossover, randomized, controlled trial.
SETTING
Comprehensive Spine and Sports Center and participating centers.
METHODS
Forty patients were randomized into saline trigger point injection, intradiscal PRP, or BMC. Follow-up was 1, 3, 6, and 12 months posttreatment. Placebo patients were randomized to PRP and BMC injection if < 50% decrease in numeric rating scale (NRS) scores in 3 months, while PRP and BMC patients to the other active group if < 50% decrease in NRS scores in 6 months.
RESULTS
Both PRP and BMC demonstrated statistically significant improvement in pain and function. All the placebo patients reported < 50% pain relief and crossed to the active arm. None of the patients had any adverse effects, hospitalization, or surgery up to 12 months posttreatment.
LIMITATIONS
The limitations of our study were the small number of patients and open-label nature of the study.
CONCLUSION
This is the only human lumbar disc study that evaluates both PRP and BMC in the same study and compares it to placebo. PRP and BMC were found to be superior to placebo in improving pain and function; however, larger randomized clinical trials are needed to answer further questions on the comparative effectiveness of various biologics as well as to identify outcome differences specific to disc pathology.
Topics: Humans; Follow-Up Studies; Low Back Pain; Lumbosacral Region; Neurosurgical Procedures; Prospective Studies; Cross-Over Studies
PubMed: 38285032
DOI: No ID Found -
American Family Physician Jul 2017
Review
Topics: Adolescent; Back; Diagnosis, Differential; Female; Humans; Nevus, Halo
PubMed: 28671374
DOI: No ID Found -
Sensors (Basel, Switzerland) Feb 2023Ground contact time (GCT) is one of the most relevant factors when assessing running performance in sports practice. In recent years, inertial measurement units (IMUs)...
Ground contact time (GCT) is one of the most relevant factors when assessing running performance in sports practice. In recent years, inertial measurement units (IMUs) have been widely used to automatically evaluate GCT, since they can be used in field conditions and are friendly and easy to wear devices. In this paper we describe the results of a systematic search, using the Web of Science, to assess what reliable options are available to GCT estimation using inertial sensors. Our analysis reveals that estimation of GCT from the upper body (upper back and upper arm) has rarely been addressed. Proper estimation of GCT from these locations could permit an extension of the analysis of running performance to the public, where users, especially vocational runners, usually wear pockets that are ideal to hold sensing devices fitted with inertial sensors (or even using their own cell phones for that purpose). Therefore, in the second part of the paper, an experimental study is described. Six subjects, both amateur and semi-elite runners, were recruited for the experiments, and ran on a treadmill at different paces to estimate GCT from inertial sensors placed at the foot (for validation purposes), the upper arm, and upper back. Initial and final foot contact events were identified in these signals to estimate the GCT per step, and compared to times estimated from an optical MOCAP (Optitrack), used as the ground truth. We found an average error in GCT estimation of 0.01 s in absolute value using the foot and the upper back IMU, and of 0.05 s using the upper arm IMU. Limits of agreement (LoA, 1.96 times the standard deviation) were [-0.01 s, 0.04 s], [-0.04 s, 0.02 s], and [0.0 s, 0.1 s] using the sensors on the foot, the upper back, and the upper arm, respectively.
Topics: Humans; Arm; Upper Extremity; Foot; Back; Running; Biomechanical Phenomena
PubMed: 36904728
DOI: 10.3390/s23052523 -
ELife Nov 2021Adaptations of the lower back to bipedalism are frequently discussed but infrequently demonstrated in early fossil hominins. Newly discovered lumbar vertebrae contribute...
Adaptations of the lower back to bipedalism are frequently discussed but infrequently demonstrated in early fossil hominins. Newly discovered lumbar vertebrae contribute to a near-complete lower back of Malapa Hominin 2 (MH2), offering additional insights into posture and locomotion in . We show that MH2 possessed a lower back consistent with lumbar lordosis and other adaptations to bipedalism, including an increase in the width of intervertebral articular facets from the upper to lower lumbar column ('pyramidal configuration'). These results contrast with some recent work on lordosis in fossil hominins, where MH2 was argued to demonstrate no appreciable lordosis ('hypolordosis') similar to Neandertals. Our three-dimensional geometric morphometric (3D GM) analyses show that MH2's nearly complete middle lumbar vertebra is human-like in overall shape but its vertebral body is somewhat intermediate in shape between modern humans and great apes. Additionally, it bears long, cranially and ventrally oriented costal (transverse) processes, implying powerful trunk musculature. We interpret this combination of features to indicate that used its lower back in both bipedal and arboreal positional behaviors, as previously suggested based on multiple lines of evidence from other parts of the skeleton and reconstructed paleobiology of .
Topics: Animals; Back; Female; Fossils; Hominidae; Locomotion; Posture
PubMed: 34812141
DOI: 10.7554/eLife.70447 -
Journal of Biomechanics May 2021Literature highlights the need for research on changes in lumbar movement patterns, as potential mechanisms underlying the persistence of low-back pain. Variability and...
Reliability of measures to characterize lumbar movement patterns, in repeated seated reaching, in a mixed group of participants with and without low-back pain: A test-retest, within- and between session.
Literature highlights the need for research on changes in lumbar movement patterns, as potential mechanisms underlying the persistence of low-back pain. Variability and local dynamic stability are frequently used to characterize movement patterns. In view of a lack of information on reliability of these measures, we determined their within- and between-session reliability in repeated seated reaching. Thirty-six participants (21 healthy, 15 LBP) executed three trials of repeated seated reaching on two days. An optical motion capture system recorded positions of cluster markers, located on the spinous processes of S1 and T8. Movement patterns were characterized by the spatial variability (meanSD) of the lumbar Euler angles: flexion-extension, lateral bending, axial rotation, temporal variability (CyclSD) and local dynamic stability (LDE). Reliability was evaluated using intraclass correlation coefficients (ICC), coefficients of variation (CV) and Bland-Altman plots. Sufficient reliability was defined as an ICC ≥ 0.5 and a CV < 20%. To determine the effect of number of repetitions on reliability, analyses were performed for the first 10, 20, 30, and 40 repetitions of each time series. MeanSD, CyclSD, and the LDE had moderate within-session reliability; meanSD: ICC = 0.60-0.73 (CV = 14-17%); CyclSD: ICC = 0.68 (CV = 17%); LDE: ICC = 0.62 (CV = 5%). Between-session reliability was somewhat lower; meanSD: ICC = 0.44-0.73 (CV = 17-19%); CyclSD: ICC = 0.45-0.56 (CV = 19-22%); LDE: ICC = 0.25-0.54 (CV = 5-6%). MeanSD, CyclSD and the LDE are sufficiently reliable to assess lumbar movement patterns in single-session experiments, and at best sufficiently reliable in multi-session experiments. Within-session, a plateau in reliability appears to be reached at 40 repetitions for meanSD (flexion-extension), meanSD (axial-rotation) and CyclSD.
Topics: Humans; Low Back Pain; Lumbosacral Region; Reproducibility of Results
PubMed: 33894470
DOI: 10.1016/j.jbiomech.2021.110435 -
PeerJ 2023Musculoskeletal disorders (MSDs), especially in the lumbar spine, are a leading concern in occupational health. Work activities associated with excessive exposure are a... (Review)
Review
BACKGROUND
Musculoskeletal disorders (MSDs), especially in the lumbar spine, are a leading concern in occupational health. Work activities associated with excessive exposure are a source of risk for MSDs. The optimal design of workplaces requires changes in both sitting and standing postures. In order to secure such a design scientifically proved quantitative data are needed that would allow for the assessment of differences in spine load due to body posture and/or exerted force. Intradiscal pressure (IP) measurement in the lumbar spine is the most direct method of estimating spinal loads. Hence, this study aims at the quantitative evaluation of differences in lumbar spine load due to body posture and exerted forces, based on IP reported in publications obtained from a comprehensive review of the available literature.
METHODOLOGY
In order to collect data from studies measuring IP in the lumbar spine, three databases were searched. Studies with IP for living adults, measured in various sitting and standing postures, where one of these was standing upright, were included in the analysis. For data to be comparable between studies, the IP for each position was referenced to upright standing. Where different studies presented IP for the same postures, those relative IPs (rIP) were merged. Then, an analysis of the respective outcomes was conducted to find the possible relationship of IPs dependent on a specific posture.
RESULTS
A preliminary analysis of the reviewed papers returned nine items fulfilling the inclusion and exclusion criteria. After merging relative IPs from different studies, rIP for 27 sitting and 26 standing postures was yielded. Some of the data were useful for deriving mathematical equations expressing rIP as a function of back flexion angle and exerted force in the form of a second degree polynomial equation for the standing and sitting positions. The equations showed that for the standing posture, the increase in IP with increasing back flexion angle is steeper when applying an external force than when maintaining body position only. In a sitting position with the back flexed at 20°, adding 10 kg to each hand increases the IP by about 50%. According to the equations developed, for back flexion angles less than 20°, the IP is greater in sitting than in standing. When the angle is greater than 20°, the IP in the sitting position is less than in the standing position at the same angle of back flexion.
CONCLUSIONS
Analysis of the data from the reviewed papers showed that: sitting without support increases IP by about 30% in relation to upright standing; a polynomial of the second degree defines changes in IP as a function of back flexion for for both postures. There are differences in the pattern of changes in IP with a back flexion angle between sitting and standing postures, as back flexion in standing increases IP more than in sitting.
Topics: Adult; Humans; Sitting Position; Standing Position; Posture; Lumbar Vertebrae; Lumbosacral Region; Musculoskeletal Diseases
PubMed: 37872945
DOI: 10.7717/peerj.16176 -
Journal of Biomechanics Feb 2024Lifting is a significant risk factor for low back pain (LBP). Different biomechanical factors including spinal loads, kinematics, and muscle electromyography (EMG)...
Lifting is a significant risk factor for low back pain (LBP). Different biomechanical factors including spinal loads, kinematics, and muscle electromyography (EMG) activities have previously been investigated during lifting activities in LBP patients and asymptomatic individuals to identify their association with LBP. However, the findings were contradictory and inconclusive. Accurate and subject-specific prediction of spinal loads is crucial for understanding, diagnosing, planning tailored treatments, and preventing recurrent pain in LBP patients. Therefore, the present study aimed to estimate the L5-S1 compressive and resultant shear loads in 19 healthy and 17 non-specific chronic LBP individuals during various static load-holding tasks (holding a 10 kg box at hip, chest, and head height) using full-body and personalized musculoskeletal models driven by subject-specific in vivo kinematic/kinetic, EMG, and physiological cross-sectional areas (PCSAs) data. These biomechanical characteristics were concurrently analyzed to identify potential differences between the two groups. Statistical analyses showed that LBP had almost no significant effect on the range of motion (trunk, lumbar, pelvis), PCSA, and EMG. There were no significant differences (p > 0.05) in the predicted L5-S1 loads. However, as the task became more demanding, by elevating the hand-load from hip to head, LBP patients experienced significant increases in both compressive (33 %, p = 0.00) and shear (25 %, p = 0.02) loads, while asymptomatic individuals showed significant increases only in compressive loads (30 %, p = 0.01). This suggests that engaging in more challenging activities could potentially magnify the effect of LBP on the biomechanical factors and increase their discrimination capacity between LBP and asymptomatic individuals.
Topics: Humans; Lumbar Vertebrae; Low Back Pain; Biomechanical Phenomena; Spine; Lumbosacral Region; Electromyography; Lifting
PubMed: 38310006
DOI: 10.1016/j.jbiomech.2024.111954 -
Musculoskeletal Science & Practice Oct 2021Since the contribution of the lumbar multifidus(LM) is not well understood in relation to non-specific low back pain(LBP), this may limit physiotherapists in choosing...
BACKGROUND
Since the contribution of the lumbar multifidus(LM) is not well understood in relation to non-specific low back pain(LBP), this may limit physiotherapists in choosing the most appropriate treatment strategy.
OBJECTIVES
This study aims to compare clinical characteristics, in terms of LM function and morphology, between subacute and chronic LBP patients from a large clinical practice cohort compared to healthy controls.
DESIGN
Multicenter case control study.
METHOD
Subacute and chronic LBP patients and healthy controls between 18 and 65 years of age were included. Several clinical tests were performed: primary outcomes were the LM thickness from ultrasound measurements, trunk range of motion(ROM) from 3D kinematic tests, and median frequency and root mean square values of LM by electromyography measurements. The secondary outcomes Numeric Rating Scale for Pain(NRS) and the Oswestry Disability Index(ODI) were administered. Comparisons between groups were made with ANOVA, p-values<0.05, with Tukey's HSD post-hoc test were considered significant.
RESULTS
A total of 161 participants were included, 50 healthy controls, 59 chronic LBP patients, and 52 subacute LBP patients. Trunk ROM and LM thickness were significantly larger in healthy controls compared to all LBP patients(p < 0.01). A lower LM thickness was found between subacute and chronic LBP patients although not significant(p = 0.11-0.97). All between-group comparisons showed no statistically significant differences in electromyography outcomes (p = 0.10-0.32). NRS showed no significant differences between LBP subgroups(p = 0.21). Chronic LBP patients showed a significant higher ODI score compared to subacute LBP patients(p = 0.03).
CONCLUSIONS
Trunk ROM and LM thickness show differences between LBP patients and healthy controls.
Topics: Case-Control Studies; Humans; Low Back Pain; Lumbosacral Region; Paraspinal Muscles; Primary Health Care
PubMed: 34271415
DOI: 10.1016/j.msksp.2021.102429