The effect of two lumbar belt designs on trunk repositioning sense in people with and without low back pain

Validation of proprioception measures of the lumbar spine

BACKGROUND

To better personalize treatment and monitor recovery of individuals with low back pain, objective tests of sensorimotor functions, such as lumbar proprioception, must be selected based on their reliability and validity. The primary objective of this study was to test the concurrent validity of three measures of lumbar proprioception.

METHODS

Thirty-one participants performed three lumbar proprioception tests (motion perception threshold, active and passive joint positioning sense), a whole-body mobility and balance (time up-and-go) and two trunk-specific postural control (threshold of stability and sensor-based sway measures) tests.

RESULTS

Only the motion perception threshold proprioception test showed some validity, correlating with the trunk-specific postural control tests [r range (positive values): 0.37 to 0.60]. The three lumbar proprioception measures were not correlated to each other. The threshold of stability measure was correlated with the time up-and-go (r = 0.37) and trunk-specific (sensor-based sway measures) postural control [r range (positive values): 0.48 to 0.77] tests.

CONCLUSION

The present study generated three original findings. Only the motion perception threshold proprioception test demonstrated its concurrent validity. In fact, the three lumbar proprioception tests performed in the present study were not correlated to each other, thus assessing different constructs. Finally, the threshold of stability protocol was validated against other tests. These findings will help in selecting the most appropriate lumbar proprioception measures to study the effects of exercise treatments in patients with back pain.

Effect of external lumbar supports on joint position sense, postural control, and postural adjustment: a systematic review

PURPOSE

To review the effects of external lumbar supports on various aspects of sensorimotor function including joint position sense (JPS), postural control, anticipatory postural adjustments (APAs), and compensatory postural adjustments (CPAs).

METHODS

A systematic literature search was performed in PubMed, EMBASE, Scopus, Ovid, Cochrane library, and Web of Science. Two reviewers selected studies which assessed the effect of lumbosacral orthosis or kinesio-tape on JPS, postural control or APAs/CPAs in subjects with and without low back pain (LBP). The methodological quality of included studies was assessed using a modified version of Downs and Black's checklist.

RESULTS

Findings demonstrated moderate effects of lumbosacral orthosis on specific aspects of sensorimotor control including JPS and to a lesser extent standing stability. These domains were not or minimally affected by application of kinesio-tape. Both orthosis and kinesio-tape had negligible effects on APAs and CPAs.

CONCLUSIONS

The positive effects of lumbar orthosis on JPS or postural control were mostly observed in conditions where sources of proprioceptive feedback are impaired (such as LBP) or absent (standing with eyes closed on an unstable surface). However, evidence does not prove significant positive effects for the application of kinesio-tape to improve sensorimotor control.IMPLICATIONS FOR REHABILITATIONWearing lumbar orthosis leads to an improvement in joint position sense.Postural stability seems to be affected to some extent by utilizing lumbar orthosis.Clinicians can administer orthosis to improve sensorimotor adaptation, especially in conditions with poor proprioception.Kinesio-tape had negligible effects on all domains of sensorimotor control.Improvement of sensorimotor function as a result of application of kinesio-tape is questionable.

The Effect of Lumbar Belts with Different Extensibilities on Kinematic, Kinetic, and Muscle Activity of Sit-to-Stand Motions in Patients with Nonspecific Low Back Pain

Although lumbar belts can be used for the treatment and prevention of low back pain, the role of the lumbar belt remains unclear without clear guidelines. This study aimed to investigate the effect of lumbar belts with different extensibilities on the kinematics, kinetics, and muscle activity of sit-to-stand motions in terms of motor control in patients with nonspecific low back pain. A total of 30 subjects participated in the study: 15 patients with nonspecific low back pain and 15 healthy adults. Participants performed the sit-to-stand motion in random order of three conditions: no lumbar belt, wearing an extensible lumbar belt, and wearing a non-extensible lumbar belt. The sit-to-stand motion's kinematic, kinetic, and muscle activity variables in each condition were measured using a three-dimensional motion analysis device, force plate, and surface electromyography. An interaction effect was found for the time taken, anterior pelvic tilt angle, and muscle activity of the vastus lateralis and biceps femoris. The two lumbar belts with different extensibilities had a positive effect on motor control in patients with nonspecific low back pain. Therefore, both types of extensible lumbar belts can be useful in the sit-to-stand motion, which is an important functional activity for patients with nonspecific low back pain.

Analysis of the Effect of Wearing Extensible and Non-Extensible Lumbar Belts on Biomechanical Factors of the Sit-to-Stand Movement and Pain-Related Psychological Factors Affecting Office Workers with Low Back Pain

This study aimed to investigate the effects of wearing extensible and non-extensible lumbar belt (LB) on biomechanical factors of the sit-to-stand (STD) movement and pain-related psychological factors affecting office workers with low back pain. Among 30 office workers, 15 with low back pain (LBP) were assigned to the experimental group and 15 healthy adults were assigned to the control group. The participants performed STD movement in random order of three different conditions: without LB (Condition 1), with extensible LB (Condition 2), and with non-extensible LB (Condition 3). Biomechanical variables of STD movement in each condition were measured using a three-dimensional motion analysis system and force plate. Pain-related psychological factors were measured only in the experimental group. Among the biomechanical factors of STD movement, an interaction effect was found in the maximum anterior pelvic tilt angle and total-phase range of motion of the trunk (p < 0.05). Pain intensity, pain-related anxiety, and pain catastrophizing were decreased in the conditions with lumbar belts (Conditions 2 and 3) compared to the condition without LB (Condition 1) (p < 0.05). Extensible and non-extensible lumbar belts engender biomechanically beneficial effects during STD movement in both office workers with LBP and healthy office workers. Further, pain intensity, pain-related anxiety, and pain catastrophizing were decreased in office workers with LBP. Therefore, both types of extensible lumbar belts may be helpful in the daily life of patients with LBP and office workers.

The effect of extensible and non-extensible lumbosacral orthoses on anticipatory postural adjustments in participants with low back pain and healthy controls

BACKGROUND

Wearing a lumbosacral orthosis (LSO) is known to influence spine mechanics, but less is known about how LSOs affect motor control. Whether the use of a LSO can negatively affect motor control of the lumbar spine is still under debate.

OBJECTIVE

The current study examined the immediate effects of two flexible LSOs (extensible and non-extensible) on the anticipatory postural adjustments that prepare the spine for a predictable perturbation.

DESIGN

A comparative study using a repeated measures design in a laboratory setting.

METHODS

Healthy controls (n = 20) and participants with low back pain (n = 40) performed a rapid arm flexion/extension cycle with and without these LSOs. The latency between the activations of the shoulder and different back (iliocostalis lumborum) and abdominal (rectus abdominis, internal and external obliques) muscles, as measured with surface electromyography, was used as the outcome.

RESULTS

The effects, which were comparable between groups and between LSOs, were mixed, with some muscles showing significantly (p ˂ 0.05) earlier activation and others showing delayed activation with the use of a LSO, relative to the control condition. The corresponding effect sizes were low to average (Hedges's g range: 0.17-0.48).

CONCLUSIONS

These findings suggest a change in the motor program before task initiation, which might be generalizable to other activities of daily living or work. However, none of the effects were large, making it difficult to provide clear conclusions with regard to their clinical relevance. It remains to be tested whether these immediate adaptations in motor planning can induce long term detrimental effects to the control of lumbar stability.

Lumbo-pelvic proprioception in sitting is impaired in subgroups of low back pain-But the clinical utility of the differences is unclear. A systematic review and meta-analysis

BACKGROUND

Altered spinal postures and altered motor control observed among people with non-specific low back pain have been associated with abnormal processing of sensory inputs. Evidence indicates that patients with non-specific low back pain have impaired lumbo-pelvic proprioceptive acuity compared to asymptomatic individuals.

OBJECTIVE

To systematically review seated lumbo-pelvic proprioception among people with non-specific low back pain.

METHODS

Five electronic databases were searched to identify studies comparing lumbo-pelvic proprioception using active repositioning accuracy in sitting posture in individuals with and without non-specific low back pain. Study quality was assessed by using a modified Downs and Black's checklist. Risk of bias was assessed using an adapted tool for cross-sectional design and case-control studies. We performed meta-analysis using a random effects model. Meta-analyses included subgroup analyses according to disability level, directional subgrouping pattern, and availability of vision during testing. We rated the quality of evidence using the GRADE approach.

RESULTS

16 studies met the eligibility criteria. Pooled meta-analyses were possible for absolute error, variable error, and constant error, measured in sagittal and transverse planes. There is very low and low certainty evidence of greater absolute and variable repositioning error in seated tasks among non-specific low back pain patients overall compared to asymptomatic individuals (sagittal plane). Subgroup analyses indicate moderate certainty evidence of greater absolute and variable error in seated tasks among directional subgroups of adults with non-specific low back pain, along with weaker evidence (low-very low certainty) of greater constant error.

DISCUSSION

Lumbo-pelvic proprioception is impaired among people with non-specific low back pain. However, the low certainty of evidence, the small magnitude of error observed and the calculated "noise" of proprioception measures, suggest that any observed differences in lumbo-pelvic proprioception may be of limited clinical utility.

PROSPERO-ID

CRD42018107671.

Cervical proprioception accuracy is impaired in patients with axial spondyloarthritis

BACKGROUND

Proprioception is the awareness of body parts and includes joint position sense, kinesthesia, and sense of force. Cervical spine is one of the major affected areas in axial spondyloarthritis (axSpA), and is an essential region for proprioceptive receptors.

OBJECTIVE

To investigate the cervical joint proprioceptive accuracy by using cervical joint positioning error (JPE) method in patients with axSpA and healthy controls.

DESIGN

Cross-sectional study.

METHODS

JPE was calculated for cervical motions in the directions of flexion, extension, rotations, and lateral flexions. Time since diagnosis, symptom duration, spinal mobility, functional status, quality of life, disease activity, and pain were evaluated in axSpA patients. Cervical JPE of axSpA patients was also compared according to radiographic status, biologic use, and existence of cervical syndesmophytes.

RESULTS

Eighty-two axSpA patients (52 males) and 71 healthy subjects (53 males) were evaluated. Cervical JPE was higher in patients with axSpA compared to healthy subjects (p < 0.001), except left lateral flexion (p = 0.10). Cervical proprioceptive accuracy for extension and left rotation was better in biologics+ subgroup compared to biologic- subgroup (p < 0.05). No other differences were detected related to radiographic status nor existence of cervical syndesmophytes (p > 0.05).

CONCLUSION

Cervical proprioception accuracy is impaired in patients with axSpA. It seems that controlling disease activity by using appropriate medication may have a positive effect on cervical proprioception accuracy.

Postural Stability in Individuals with and without Sacroiliac Joint Dysfunction Before and After Pelvic Belt Application

Background: Sacroiliac Joint Dysfunction (SIJD) is considered an origin of low-back pain. It can change the motor control strategy and postural control (PC). Objectives: We aimed to find any probable differences in PC between subjects with and without SIJD and determine the effects of the pelvic belt (PB) on PC. Methods: Thirty-eight subjects were assigned into two equal groups with and without SIJD. They started to walk from the place marked on a force plate for 10 seconds after hearing an auditory signal and performed three attempts for each foot. They repeated six more ones with PB. Raw data were imported to an excel software (version 2007) spreadsheet to calculate the reaction time (RT) and anticipatory postural adjustment (APA) as the components of PC. Results: Our results showed a significant difference in RT between the SIJD-affected and non-affected sides (P = 0.035), but there was no significant difference in APA (P = 0.057). There were significant differences in RT and APAs between the control and SIJD-affected side groups (P = 0.001 and P = 0.010, respectively). The PB application showed a significant difference in RT and APAs of the SIJD-affected side (P = 0.001 and P = 0.047, respectively). Conclusions: It seems pain could lead to the postural sway into instability and change the motor control strategy. The proprioception signals from the neuromuscular system of SIJ improved after PB. Therefore, PB, as a feasible tool, can be recommended for PC improvement.

Differences in Proprioception Between Young and Middle-Aged Adults With and Without Chronic Low Back Pain

Introduction: While young adults with chronic low back pain (CLBP) exhibit impaired lumbar proprioception, it remains unclear if the same phenomenon is observed in middle-aged adults with CLBP. Objectives: This study aimed to investigate whether young or middle-aged adults with CLBP displayed different proprioception ability as compared to age-matched asymptomatic controls. Methods: Sixty-four young adults with [median age:34 [interquartile range (IQR): 29-37] years] and without [median age:29 (IQR; 23-34) years] CLBP, and 87 middle-aged adults with [median age:53 (IQR: 49-58) years] and without [median age: 54 (IQR: 45-64) years] CLBP underwent postural sway tests on a force-plate with (unstable surface) and without a foam (stable surface), while bilateral L5/S1 multifidi and triceps-surae were vibrated separately. An individual's proprioception reweighting ability was estimated by relative proprioceptive reweighting (RPW). Higher RPW values indicate less reliance on lumbar multifidus proprioceptive signals for balance. Participants also underwent lumbar repositioning tests in sitting to determine repositioning errors in reproducing target lumbar flexion/extension positions. Results: Young adults with CLBP demonstrated significantly higher median RPW values than age-matched asymptomatic controls for maintaining standing balance [stable surface: CLBP: 0.9 (IQR: 0.7-0.9), asymptomatic: 0.7 (IQR: 0.6-0.8), p < 0.05; unstable surface: CLBP: 0.6 (IQR: 0.4-0.8), asymptomatic: 0.5 (IQR: 0.3-0.7), p < 0.05]. No significant differences in repositioning error were noted between young or middle-aged adults with and without CLBP (p > 0.05). RPW values were unrelated to repositioning errors in all groups (p > 0.05). Conclusion: Young adults with CLBP, and middle-aged adults with and without CLBP had inferior proprioceptive reweighting capability. This finding may indicate potential age-related deterioration in central and peripheral processing of lumbar proprioceptive signals. Future studies should use advanced imaging and/or electroencephalogram to determine mechanisms underlying changes in proprioceptive reweighting in middle-aged adults.

Non-rigid lumbar supports for the management of non-specific low back pain: A literature review and meta-analysis

BACKGROUND

Clinical practice guidelines for non-specific low back pain do not recommend the use of non-rigid lumbar supports (NRLSs) despite the publication of several positive randomized controlled studies.

OBJECTIVE

We conducted a systematic review with meta-analysis to assess the efficacy of NRLSs in the treatment and prevention of non-specific low back pain.

METHODS

We searched for reports of randomized controlled trials in PubMed, Cochrane Library, EMBASE, Science Direct and Pedro databases. Data were analyzed by disease stage (acute, subacute, and chronic) and type of prevention (primary and secondary). The analysis of methodological quality involved the Physiotherapy Evidence Database (PEDro) scale.

RESULTS

Of the 1581 records retrieved, only 4 full-text articles were included, with 777 patients: 378 in the NRLS group, and 348 in the control group. NRLSs conferred greater amelioration of disability (effect size -0.54, 95% CI -0.90; -0.17) and pain (-0.29, -0.46; -0.12) than standard management. Insufficient data prevented a comparison of the efficiency for acute, subacute and recurrent low back pain as well as meta-regression of responder phenotypes (sociodemographic and other patient characteristics).

CONCLUSION

We demonstrated the overall efficacy of NRLSs for both disability and pain. However, further studies are needed to assess which patients can benefit the most from lumbar supports based on patient phenotype and the characteristics of low back pain. PROSPERO (CRD42018109855).

A randomized controlled trial comparing the long-term use of soft lumbosacral orthoses at two different pressures in patients with chronic nonspecific low back pain

BACKGROUND

There is concern that wearing soft lumbosacral orthoses for prolonged periods may impair motor function. Moreover, the pressure applied by lumbosacral orthoses on the abdominal wall is usually ignored when these orthoses are prescribed.

METHOD

In this randomized controlled trial study, 48 patients with chronic nonspecific low back pain were randomly divided into high pressure, normal pressure and control groups. All groups received medication for 4 weeks. The normal pressure and high pressure groups, in addition to medication, used soft lumbosacral orthoses at normal pressure and 50% increased pressure, respectively. Motor function outcome measures were strength, endurance, proprioception and electromyographic activity of the trunk muscles. Clinical outcome measures were pain and disability, which were evaluated in two sessions before and after a 4-week interval.

FINDINGS

Isometric strength, endurance and most of the electromyographic parameters were generally unaffected by wearing the lumbosacral orthosis. Pain improved in all groups, and disability and proprioception improved in the high pressure and normal pressure groups. Between-group differences in these three measures indicated better results in the lumbosacral orthoses groups than in the control group. The improvements in pain and proprioception were significantly greater in the high pressure group than the normal pressure group.

INTERPRETATION

Long-term use of lumbosacral orthoses had no significant adverse effects on motor function or clinical factors in patients with chronic low back pain. Increasing lumbosacral orthosis tightness may improve motor functioning and the clinical efficacy of the orthosis.

CLINICAL TRIAL REGISTRATION NUMBER

Code: IRCT201708192391N38.

The effect of extensible and non-extensible lumbar belts on trunk muscle activity and lumbar stiffness in subjects with and without low-back pain

BACKGROUND

Lumbar belts have been shown to increase lumbar stiffness, but it is unclear if this is associated with trunk muscle co-contraction, which would increase the compression on the spine. It has been hypothesized that lumbar belts increase lumbar stiffness by increasing intra-abdominal pressure, which would increase spinal stability without increasing the compressive load on the spine.

METHODS

Trunk muscle activity and lumbar stiffness and damping were measured in healthy and low-back pain subjects during three conditions: no lumbar belt; wearing an extensible lumbar belt; wearing a non-extensible lumbar belt. Muscle activity was measured while subjects performed controlled forward and backward 20° trunk sways. Lumbar stiffness and damping were measured by applying random continuous perturbation to the chest.

FINDINGS

External oblique activity was decreased when wearing either lumbar belt during all phases of movement, while rectus abdominis and iliocostalis activity were decreased during the phase of movement where the muscles were maximally active while wearing either belt. Trunk stiffness was greatly increased by wearing either belt. There were no consistent differences in either lumbar stiffness or muscle activity between the two belts. Wearing a lumbar belt had little to no effect on damping. There were no group differences in any of the measures between healthy and low-back pain populations.

INTERPRETATION

The findings are consistent with the hypothesis that lumbar belts can increase spinal stability by increasing intra-abdominal pressure, without any increase in the compressive load on the spine. The findings can also be generalized, for the first time, to subjects with low-back pain.

The effect of extensible and non-extensible lumbar belts on trunk postural balance in subjects with low back pain and healthy controls

BACKGROUND

Previous findings suggest that wearing a lumbar belt may benefit some patients with low back pain; however, the mechanisms of action are not yet fully understood.

RESEARCH QUESTION

The effect of wearing two flexible (extensible and non-extensible) lumbar belts on trunk postural control was investigated during an unstable sitting task.

METHODS

Healthy subjects and subjects with LBP sat on a wobbling chair, with and without the lumbar belts. Chair rotation was measured in the sagittal and frontal planes, and 10 linear and nonlinear measures of balance were computed to assess the quantity (3 measures) and quality (7 measures) of the movements.

RESULTS

Both lumbar belts induced similar changes in specific measures of trunk postural control, for both subject groups, generally indicative of more instability and less controllability, but with low effect sizes (0.14 and 0.40). Subjects with LBP also showed lower entropy (complexity; effect size 0.93) and higher determinism (predictability; effect size 0.56) than healthy controls, under all test conditions. These findings indicate that the subjects with LBP used a less complex, more predictable trunk postural control strategy, suggestive of impaired adaptability and responsiveness to dynamic trunk postural control demands. The findings also suggest other factors related to dynamic adaptability may be impaired by lumbar belt use.

SIGNIFICANCE

The effects of the lumbar belts on trunk postural control were small, however, their practical implications for the management of LBP remain to be determined in relation to other effects of lumbar belts (e.g. increased mechanical stiffness).

The new "Tehran Back Belt": Design then testing during a simulated sitting task improved biomechanical spine muscle activity

Background: Spinal load and muscle activity in occupation settings is an area of increasing concern. Regarding technological advancements, in diverse occupations the spinal loads have increased through constrained seated postures. Back belts are consequently used in prophylactic and conservative management of occupational low back pain (LBP) in two distinct settings, prevention in industry, and treatment in LBP management. Industrial sites utilize belts for LBPprophylaxis on a large scale with their design and user experience (UE) influencing both the effectiveness and the workers’ compliance. This pilot study aims at determining the effectiveness of the new Tehran Back Belt (TBB) and assesses both UE and biomechanical effect (BE) on para-spinal muscle activity in healthy subjects.

Methods: A pretest-posttest study. Stage-1, design and fabrication of the TBB. Stage-2, the UE of the designed belt evaluated in healthy volunteers (n=30) via a checklist. The BE was determined from the level of lumbar extensor and trunk flexor muscle activity gauged during two test conditions of sitting posture (with and without belt) over 35-minute periods.

Results: Most subjects (>90%) reported high ‘ease of use’ and ‘comfort’ while wearing the TBB.The BE statistical analysis showed significantly reduced EMG activity levels for the longissimus(P = 0.012, η²=0.24), rectus abdominis (P=0.024, η²=0.18) and internal oblique (P=0.001,η²=0.44) muscles in belt-use conditions.

Conclusion: Decreased muscle activity while using the TBB is potentially advantageous for workers as spinal muscle activity is significantly reduced. Further investigations for longer duration effects and during real work office-based activities are warranted.