The influence of exercise on pain, disability and quality of life in office workers with chronic neck pain: A systematic review and meta-analysis

BACKGROUND

Exercise is recommended for office workers with neck pain. However, recent reviews evaluated the effectiveness of workplace interventions only.

OBJECTIVES

To evaluate the effect of exercise on pain, disability, and quality of life (QoL) in office workers with chronic neck pain.

DESIGN

Systematic review with meta-analysis.

METHODS

Electronic databases were searched from inception to April 30, 2022, to identify studies in which participants were adults aged ≥18 years undergoing any form of neck exercises (e.g., strengthening, motor control) or physical activity (e.g., aerobic exercise) performed for a minimum of two-weeks without any other additional treatment besides advice or education. Two reviewers independently screened papers and determined the certainty of the evidence.

RESULTS

Eight randomised controlled trials met the eligibility criteria. Seven studies reported a significant decrease in Visual Analogue Scale (VAS) scores for neck pain intensity and five studies reported a significant decrease in Neck Disability Index (NDI) scores following strengthening exercises. Only one study assessed the effect of strengthening exercises on QoL and reported no significant effect. All eight included studies had a high risk of bias and the overall certainty of evidence was low. Meta-analyses demonstrated a significant decrease of neck pain intensity and disability for strengthening exercises compared to a control (p < 0.01).

CONCLUSION

There is low certainty of evidence that strengthening of the neck, shoulder and scapular musculature is effective at reducing neck pain and disability in office workers. Further research evaluating the effect of exercise on QoL is required.

Changes in Multiple Aspects of Pain Outcomes After Rehabilitation: Analysis of Pain Data in a Randomized Controlled Trial Evaluating the Effects of Adding Sensorimotor Training to Manual Therapy and Exercise for Chronic Neck Pain

OBJECTIVES

To examine changes in pain outcomes to fully evaluate the effect of adding sensorimotor training to manual therapy and exercise in patients with chronic neck pain and sensorimotor deficits. Concordance was examined between pain distribution and pain intensity and patient-reported outcomes.

METHODS

Participants (n=152) were randomly allocated into 4 intervention groups: One group received local neck treatment (NT) comprising manual therapy and exercise and the other 3 groups received additional sensorimotor training (either joint position sense/oculomotor exercises, balance exercises or both). Treatment was delivered twice a week for 6 weeks. Pain and patient-reported outcomes were measured at baseline, posttreatment, and 3-, 6- and 12-month follow-ups.

RESULTS

There were greater changes in pain location, extent, and intensity at 6- and 12-month follow-ups in the sensorimotor training groups compared with the NT group ( P <0.05). A greater number of patients in the sensorimotor training groups gained ≥50% reduction in pain extent and intensity relative to the NT group at 6 and 12 months ( P <0.05). Clinical improvement in pain extent was concordant with pain intensity (adjusted kappa=056 to 0.66, %agreement=78.3 to 82.9, P <0.001) and disability (adjusted kappa=0.47 to 0.58, % agreement=73.7 to 79.0, P <0.01) at 3-, 6- and 12-month follow-ups, but not with function and well-being. The concordance tended to decline with time.

DISCUSSION

Multiple aspects of the pain experience improved in the longer term by adding sensorimotor training to NT for patients with neck pain and sensorimotor deficits. The concordance between pain and patient-reported outcomes was not always evident and varied over time, suggesting the need for multidimensional assessments of pain.

Higher Neck Pain Intensity and Pain Catastrophizing Soon After A Whiplash Injury Partially Explain the Presence of Persistent Headache: A Prospective Study

OBJECTIVE

To understand whether pain-related factors soon after a whiplash injury can explain the presence of chronic headache.

MATERIALS AND METHODS

A prospective study with a follow-up of 6 months was performed including 42 patients with acute whiplash-associated disorders. Neck pain intensity, the Neck Disability Index, the Tampa Scale Kinesiophobia, Pain Catastrophizing Scale, and the Anxiety State-Trait Scale were assessed at baseline. Differences in clinical characteristics between those with and without headache at 6 months were determined. The relative risk of presenting with headache was evaluated. A logistic regression model was performed to assess which factors at baseline could explain the presence of headache at 6 months.

RESULTS

At 6 months, 1/3 of the sample presented with chronic headache. Significant differences were found for several outcome measures when people with and without headache were compared (P<0.001). The highest relative risk of presenting with headache was found for moderate/severe levels of pain catastrophizing during the acute phase (RR=15.00, 95%CI=3.93, 57.22). The level of neck pain intensity and pain catastrophizing at baseline partially explained the presence of headache at 6 months (R2=0.627).

DISCUSSION

The risk of presenting with persistent headache attributed to a whiplash injury is increased when people present with higher neck pain intensity and pain catastrophizing soon after a whiplash injury. Evaluating neck pain intensity and pain catastrophizing at baseline may assist in identifying those more likely to develop chronic headache, potentially providing an opportunity for early targeted interventions.

Prognostic Factors of Perceived Disability and Perceived Recovery After Whiplash: A Longitudinal, Prospective Study With One-year Follow-up

OBJECTIVES

The understanding of the role that cognitive and emotional factors play in how an individual recovers from a whiplash injury is important. Hence, we sought to evaluate whether pain-related cognitions (self-efficacy beliefs, expectation of recovery, pain catastrophizing, optimism, and pessimism) and emotions (kinesiophobia) are longitudinally associated with the transition to chronic whiplash-associated disorders in terms of perceived disability and perceived recovery at 6 and 12 months.

METHODS

One hundred sixty-one participants with acute or subacute whiplash-associated disorder were included. The predictors were: self-efficacy beliefs, expectation of recovery, pain catastrophizing, optimism, pessimism, pain intensity, and kinesiophobia. The 2 outcomes were the dichotomized scores of perceived disability and recovery expectations at 6 and 12 months. Stepwise regression with bootstrap resampling was performed to identify the predictors most strongly associated with the outcomes and the stability of such selection.

RESULTS

Baseline perceived disability, pain catastrophizing, and expectation of recovery were the most likely to be statistically significant, with an overage frequency of 87.2%, 84.0%, and 84.0%, respectively.

CONCLUSION

Individuals with higher expectations of recovery and lower levels of pain catastrophizing and perceived disability at baseline have higher perceived recovery and perceived disability at 6 and 12 months. These results have important clinical implications as both factors are modifiable through health education approaches.

A Profile of Isometric Cervical Strength in Elite Professional Male Rugby Players

OBJECTIVES: To (1) provide position-specific normative data for isometric cervical muscle strength and endurance in professional, male rugby players and (2) assess the relationship between age, height, weight, and playing position with cervical muscle strength and endurance. DESIGN: Cross-sectional study. METHODS: Professional rugby players completed peak isometric cervical strength testing followed by a test of cervical muscle endurance. Descriptive statistics for continuous variables with strength normalized to body weight were performed. Multiple linear regression was used to estimate associations between strength measurements. RESULTS: In total, 136 players participated including front-row forwards (27%), other forwards (28%), and backs (45%). Front-row forwards had significantly greater peak isometric cervical muscle strength than other position groups, with backs having the lowest strength. Extension produced the highest force for all 3 position groups (429 N ± 104 N), whereas flexion produced the least (275 N ± 65 N). Age was associated with increased isometric cervical muscle strength. There was a statistically significant relationship between peak flexion strength and flexion endurance (P = .003). The average time for the endurance tests were 55.7 (±17.1) seconds and 52.9 (±20.1) seconds for extension and flexion, respectively. Other forwards had lower cervical extension muscle endurance than backs and front-row forwards. CONCLUSIONS: Normative values for peak and endurance isometric strength in professional rugby players illustrate significant differences between playing position. Consider age, body weight, and intraindividual variability when interpreting cervical strength and endurance results. J Orthop Sports Phys Ther 2024;54(3):1-8. Epub 29 January 2024. doi:10.2519/jospt.2024.11830.

Low Back Pain-Induced Dynamic Trunk Muscle Control Impairments Are Associated with Altered Spatial EMG-Torque Relationships

PURPOSE

We quantified the relationship between high-density surface electromyographic (HDsEMG) oscillations (in both time and frequency domains) and torque steadiness during submaximal concentric/eccentric trunk extension/flexion contractions, in individuals with and without chronic low back pain (CLBP).

METHODS

Comparisons were made between regional differences in HDsEMG amplitude and HDsEMG-torque cross-correlation and coherence of the thoracolumbar erector spinae (ES), rectus abdominis (RA), and external oblique (EO) muscles between the two groups. HDsEMG signals were recorded from the thoracolumbar ES with two 64-electrode grids and from the RA and EO muscles with a single 64-electrode grid placed over each muscle. Torque signals were recorded with an isokinetic dynamometer. Coherence (δ band (0-5 Hz)) and cross-correlation analyses were used to examine the relationship between HDsEMG and torque signals. For this purpose, we used principal component analysis to reduce data dimensionality and improve HDsEMG-based torque estimation.

RESULTS

We found that people with CLBP had poorer control during both concentric and eccentric trunk flexion and extension. Specifically, during trunk extension, they exhibited a higher HDsEMG-torque coherence in more cranial regions of the thoracolumbar ES and a higher HDsEMG cross-correlation compared with asymptomatic controls. During trunk flexion movements, they demonstrated higher HDsEMG amplitude of the abdominal muscles, with the center of activation being more cranial and a higher contribution of this musculature to the resultant torque (particularly the EO muscle).

CONCLUSIONS

Our findings underscore the importance of evaluating torque steadiness in individuals with CLBP. Future research should consider the value of torque steadiness training and HDsEMG-based biofeedback for modifying trunk muscle recruitment strategies and improving torque steadiness performance in individuals with CLBP.

Reliability of the Pen-on-Paper Pain Drawing Analysis Using Different Scanning Procedures

INTRODUCTION

Pen-on-paper pain drawing are an easily administered self-reported measure that enables patients to report the spatial distribution of their pain. The digitalization of pain drawings has facilitated the extraction of quantitative metrics, such as pain extent and location. This study aimed to assess the reliability of pen-on-paper pain drawing analysis conducted by an automated pain-spot recognition algorithm using various scanning procedures.

METHODS

One hundred pain drawings, completed by patients experiencing somatic pain, were repeatedly scanned using diverse technologies and devices. Seven datasets were created, enabling reliability assessments including inter-device, inter-scanner, inter-mobile, inter-software, intra- and inter-operator. Subsequently, the automated pain-spot recognition algorithm estimated pain extent and location values for each digitized pain drawing. The relative reliability of pain extent analysis was determined using the intraclass correlation coefficient, while absolute reliability was evaluated through the standard error of measurement and minimum detectable change. The reliability of pain location analysis was computed using the Jaccard similarity index.

RESULTS

The reliability analysis of pain extent consistently yielded intraclass correlation coefficient values above 0.90 for all scanning procedures, with standard error of measurement ranging from 0.03% to 0.13% and minimum detectable change from 0.08% to 0.38%. The mean Jaccard index scores across all dataset comparisons exceeded 0.90.

CONCLUSIONS

The analysis of pen-on-paper pain drawings demonstrated excellent reliability, suggesting that the automated pain-spot recognition algorithm is unaffected by scanning procedures. These findings support the algorithm's applicability in both research and clinical practice.

Network analyses reveal the interaction between physical features, fear of movement and neck pain and disability in people with acute and chronic whiplash-associated disorders

BACKGROUND AND OBJECTIVE

A network analysis can be used to quantitatively assess and graphically describe multiple interactions. This study applied network analyses to determine the interaction between physical and pain-related factors and fear of movement in people with whiplash-associated disorders (WAD) during periods of acute and chronic pain.

METHODS

Physical measurements, including pressure pain-thresholds (PPT) over neural structures, cervical range of motion, neck flexor and extensor endurance and the cranio-cervical flexion test (CCFT), in addition to subjective reports including the Tampa Scale of Kinesiophobia (TSK-11), Neck Disability Index (NDI) and neck pain and headache intensity, were assessed at baseline in 47 participants with acute WAD. TSK-11, NDI and pain intensity were assessed for the same participants 6 months later (n = 45). Two network analyses were conducted to estimate the associations between features at baseline and at 6 months and their centrality indices.

RESULTS

Both network analyses revealed that the greatest weight indices were found for NDI and CCFT at baseline and for neck pain and headache intensity and NDI and TSK-11 at both time points. Associations were also found betweeen cervical muscle endurance and neck pain intensity in the acute phase. Cervical muscle endurance assesssed during the acute phase was also associated with NDI after 6 months - whereas PPT measured at baseline was associsated with headache intensity after 6 months.

CONCLUSION

The strongest associations were found for headache and neck pain intensity and neck disability and fear of movement, both during acute pain and when mesured 6 months later. The extent of neck endurance and measures of PPT at baseline may be associated with neck disability and headache, respectively, 6 months after a whiplash injury.

SIGNIFICANCE

Through two network analyses, we evaluated the interaction between pain-related factors, fear of movement, neck disability and physical factors in people who had experienced a whiplash injury. We demonstrated that physical factors may be involved in the maintenance and development of chronic pain after a whiplash injury. Nevertheless, the strongest associations were found for headache and neck pain intensity and neck disability and fear of movement, both during acute and chronic phases.

Outcome measures for young people with adolescent idiopathic scoliosis: A qualitative exploration of healthcare professionals' perceptions and practices

BACKGROUND

Limited knowledge exists on current use of patient reported outcome measures (PROMs) and performance measures for adolescents with idiopathic scoliosis (AIS), as well as health care professionals' (HCPs) perceived barriers and facilitators towards their use. This study's objectives were: 1) to explore current practice of HCPs when assessing outcomes for AIS 2) to understand perceived barriers and facilitators of HCPs to use PROMs 3) to understand perceived barriers and facilitators of HCPs to use performance measures.

METHODS

A qualitative study recruited a purposive sample of HCPs from a tertiary hospital in the United Kingdom. Mean years of experience managing individuals with AIS was 11.8 years; and included surgeons, physiotherapists and nurses, educated at Bachelor, Masters and Doctoral level. Consent to participate and demographic information were collected in advance of the interviews. In-depth, virtual semi-structured interviews were informed by a topic guide based on current evidence. Interviews of approximately 45 minutes were audio and video recorded and transcribed verbatim alongside written field notes. Data were coded and analysed using inductive thematic analysis, involving researchers with topic and methodological expertise and input from a patient representative.

RESULTS

Two themes emerged regarding current practice of using PROMs routine practice and personal evaluations. Four themes emerged as barriers to using PROMs for individuals with AIS: priority and support (e.g., HCPs focus on providing care), practical challenges (e.g., inadequate PROMs), patient-related challenges (e.g., patient preferences) and knowledge, education, and perceived value. Two themes emerged as facilitators: quality existing measure (e.g., sufficient psychometric properties), and priority and support (e.g., research department/culture). Themes for barriers to use performance measures were practicality (e.g., need physical space) and perceived value and knowledge (e.g., PROMs are more important), while the one theme for facilitators was practical consideration (e.g., acceptability).

CONCLUSIONS

Although HCPs perceived the value of using outcome measures, current practice indicates limited use for individuals with AIS. The findings revealed different barriers and facilitators to implement PROMs in practice. Adopting performance measure are limited due to lack of knowledge and perceived value alongside the practicality, while considering practical factors can improve the use of these measures in practice.

Measurement properties of cervical joint position error in people with and without neck pain: a systematic review and narrative synthesis

INTRODUCTION

Proprioception can be impaired in people with neck pain. The cervical joint position sense test, which measures joint position error (JPE), is the most common test used to assess neck proprioception. The aim of this systematic review was to assess the measurement properties of this test for the assessment of people with and without neck pain.

METHODS

This systematic review was registered prospectively on Prospero (CRD42020188715). It was designed using the COSMIN guidelines and reported in line with the PRISMA checklist. Two reviewers independently searched Medline, Embase, SportDiscus, and CINAHL Plus databases from inception to the 24th July 2022 with an update of the search conducted until 14th of October 2023. The COSMIN risk of bias checklist was used to assess the risk of bias in each study. The updated criteria for good measurement properties were used to rate individual studies and then the overall pooled results. The level of evidence was rated by two reviewers independently using a modified GRADE approach.

RESULTS

Fifteen studies were included in this review, 13 reporting absolute JPE and 2 reporting constant JPE. The measurement properties assessed were reliability, measurement error, and validity. The measurement of JPE showed sufficient reliability and validity, however, the level of evidence was low/very low for both measurement properties, apart from convergent validity of the constant JPE, which was high.

CONCLUSION

The measure of cervical JPE showed sufficient reliability and validity but with low/very low levels of evidence. Further studies are required to investigate the reliability and validity of this test as well as the responsiveness of the measure.

Reliability, Measurement Error, Responsiveness, and Minimal Important Change of the Patient-Specific Functional Scale 2.0 for Patients With Nonspecific Neck Pain

OBJECTIVE

The Patient-Specific Functional Scale (PSFS) is a patient-reported outcome measure used to assess functional limitations. Recently, the PSFS 2.0 was proposed; this instrument includes an inverse numeric rating scale and an additional list of activities that patients can choose. The aim of this study was to assess the test-retest reliability, measurement error, responsiveness, and minimal important change of the PSFS 2.0 when used by patients with nonspecific neck pain.

METHODS

Patients with nonspecific neck pain completed a numeric rating scale, the PSFS 2.0, and the Neck Disability Index at baseline and again after 12 weeks. The Global Perceived Effect (GPE) was also collected at 12 weeks and used as an anchor. Test-retest measurement was assessed by completion of a second PSFS 2.0 after 1 week. Measurement error was calculated using a Bland-Altman plot. The receiver operating characteristic method with the anchor (GPE) functions as the reference standard was used for calculating the minimal important change.

RESULTS

One hundred patients were included, with 5 lost at follow-up. No floor and ceiling effects were reported. In the test-retest analysis, the mean difference was 0.15 (4.70 at first test and 4.50 at second test). The ICC (mixed models) was 0.95, indicating high agreement (95% CI = 0.92-0.97). For measurement error, the upper and lower limits of agreement were 0.95 and -1.25 points, respectively, with a smallest detectable change of 1.10. The minimal important change was determined to be 2.67 points. The PSFS 2.0 showed satisfactory responsiveness, with an area under the curve of 0.82 (95% CI = 0.70-0.93). There were substantial to high correlations between the change scores of the PSFS 2.0 and the Neck Disability Index and GPE (0.60 and 0.52, respectively; P < .001).

CONCLUSION

The PSFS 2.0 is a reliable and responsive patient-reported outcome measure for use by patients with neck pain.

Effect of movement-evoked and tonic experimental pain on muscle force production

INTRODUCTION

When performing an exercise or a functional test, pain that is evoked by movement or muscle contraction could be a stronger stimulus for changing how individuals move compared to tonic pain. We investigated whether the decrease in muscle force production is larger when experimentally-induced knee pain is directly associated to the torque produced (movement-evoked) compared to a constant painful stimulation (tonic).

METHODS

Twenty-one participants performed three isometric knee extension maximal voluntary contractions without pain (baseline), during pain, and after pain. Knee pain was induced using sinusoidal electrical stimuli at 10 Hz over the infrapatellar fat pad, applied continuously or modulated proportionally to the knee extension torque. Peak torque and contraction duration were averaged across repetitions and normalized to baseline.

RESULTS

During tonic pain, participants reported lower pain intensity during the contraction than at rest (p < 0.001), whereas pain intensity increased with contraction during movement-evoked pain (p < 0.001). Knee extension torque decreased during both pain conditions (p < 0.001), but a larger reduction was observed during movement-evoked compared to tonic pain (p < 0.001). Participants produced torque for longer during tonic compared to movement-evoked pain (p = 0.005).

CONCLUSION

Our results indicate that movement-evoked pain was a more potent stimulus to reduce knee extension torque than tonic pain. The longer contraction time observed during tonic pain may be a result of a lower perceived pain intensity during muscle contraction. Overall, our results suggest different motor adaptation to tonic and movement-evoked pain and support the notion that motor adaptation to pain is a purposeful strategy to limit pain. This mechanistic evidence suggests that individuals experiencing prevalently tonic or movement-evoked pain may exhibit different motor adaptations, which may be important for exercise prescription.

Home-based arm cycling exercise improves trunk control in persons with incomplete spinal cord injury: an observational study

Arm cycling is used for cardiorespiratory rehabilitation but its therapeutic effects on the neural control of the trunk after spinal cord injury (SCI) remain unclear. We investigated the effects of single session of arm cycling on corticospinal excitability, and the feasibility of home-based arm cycling exercise training on volitional control of the erector spinae (ES) in individuals with incomplete SCI. Using transcranial magnetic stimulation, we assessed motor evoked potentials (MEPs) in the ES before and after 30 min of arm cycling in 15 individuals with SCI and 15 able-bodied controls (Experiment 1). Both groups showed increased ES MEP size after the arm cycling. The participants with SCI subsequently underwent a 6-week home-based arm cycling exercise training (Experiment 2). MEP amplitudes and activity of the ES, and movements of the trunk during reaching, self-initiated rapid shoulder flexion, and predicted external perturbation tasks were measured. After the training, individuals with SCI reached further and improved trajectory of the trunk during the rapid shoulder flexion task, accompanied by increased ES activity and MEP amplitudes. Exercise adherence was excellent. We demonstrate preserved corticospinal drive after a single arm cycling session and the effects of home-based arm cycling exercise training on trunk function in individuals with SCI.

Shear Wave Tensiometry Can Detect Loading Differences Between Operated and Unaffected Achilles Tendon

BACKGROUND

The clinically relevant healing process of a ruptured and repaired Achilles tendon (AT) can last more than a year. The purpose of this cross-sectional study was to test if shear wave tensiometry is able to detect AT loading changes between a surgically managed AT rupture versus the unaffected contralateral tendon. Our secondary aims were to evaluate differences in mechanical properties when measured with myotonometry and morphological properties of the tendons measured with ultrasonographic imaging.

METHODS

Twenty-one patients with surgically treated AT ruptures were investigated 12-37 months after surgery. Tendon load was measured using a shear wave tensiometer composed of an array of 4 accelerometers fixed on the tendon. Shear wave speed along the Achilles tendon was evaluated at different levels of ankle torque for both the operated and the unaffected side. Mechanical properties of the tendons were evaluated using MyotonPRO and morphological properties using ultrasonographic imaging. Friedman test was used to assess differences in AT wave speed, stiffness, thickness, and cross-sectional area between the operated and the unaffected tendon.

RESULTS

We found a significant shear wave speed difference between sides at every ankle joint torque (P < .05) with a large effect size for the lowest ankle torque and small to medium effect sizes for higher ankle torque. Stiffness, thickness, and cross-sectional area of the operated tendon remained significantly higher compared to the unaffected side.

CONCLUSION

In this cohort, we found that shear wave tensiometry can detect differences between operated and unaffected AT during a standardized loading procedure. The shear wave speed along the operated tendon, as well as the mechanical and morphologic properties, remains higher for 1-3 years after a rupture.

LEVEL OF EVIDENCE

Level III, case-control study.

Spinal kinematic variability is increased in people with chronic low back pain during a repetitive lifting task

Changes in spinal kinematic variability have been observed in people with chronic non-specific LBP (CNSLBP) during the performance of various repetitive functional tasks. However, the direction of these changes (i.e., less or more kinematic variability) is not consistent. This study aimed to assess differences in kinematic variability of the 3D angular displacement of thoracic and lumbar spinal segments in people with CNSLBP compared to asymptomatic individuals during a repetitive lifting task. Eleven people with CNSLBP and 11 asymptomatic volunteers performed 10 cycles of multi-planar lifting movements while spinal kinematics were recorded. For the three planes of motion, point-by-point standard deviations (SDs) were computed across all cycles of lifting and the average was calculated as a measure of kinematic variability for both segments. People with CNSLBP displayed higher thoracic (F = 8.00, p = 0.010, ηp2 = 0.286) and lumbar kinematic variability (F = 5.48, p = 0.030, ηp2 = 0.215) in the sagittal plane. Moreover, group differences were observed in the transversal plane for thoracic (F = 7.62, p = 0.012, ηp2 = 0.276) and lumbar kinematic variability (F = 5.402, p = 0.031, ηp2 = 0.213), as well as in the frontal plane for thoracic (F = 7.27, p = 0.014, ηp2 = 0.267) and lumbar kinematic variability (F = 6.11, p = 0.022, ηp2 = 0.234), all showing higher variability in those with CNSLBP. A significant main effect of group was not detected (p > 0.05) for spinal range of motion (ROM). Thus, people with CNSLBP completed the lifting task with the same ROM in all three planes of motion as observed for asymptomatic individuals, yet they performed the lifting task with higher spinal kinematic cycle-to-cycle variation.

High-density surface electromyography allows to identify risk conditions and people with and without low back pain during fatiguing frequency-dependent lifting activities

Low back pain (LBP) is a leading cause of disability in the workplace, often caused by manually lifting of heavy loads. Instrumental-based assessment tools are used to quantitatively assess the biomechanical risk of lifting activities. This study aims to verify that, during the execution of fatiguing frequency-dependent lifting, high-density surface electromyography (HDsEMG) allows the discrimination of healthy controls (HC) versus people with LBP and biomechanical risk levels. Fifteen HC and eight people with LBP performed three lifting tasks with a progressively increasing lifting index, each lasting 15 min. Erector spinae (ES) activity was recorded using HDsEMG and amplitude parameters were calculated to characterize the spatial distribution of muscle activity. LBP group showed a less ES activity than HC (lower root mean square across the grid and of the activation region) and an involvement of the same muscular area across the task (lower coefficient of variation of the center of gravity of muscle activity). The results indicate the usefulness of HDsEMG parameters to classify risk levels for both HC and LBP groups and to determine differences between them. The findings suggest that the use of HDsEMG could expand the capabilities of existing instrumental-based tools for biomechanical risk classification during lifting activities.

Do metrics derived from self-reported and clinician-reported pain drawings agree for individuals with chronic low back pain?

BACKGROUND

Clinicians commonly use pain drawings to define the spatial extent and location of a person's pain, but limited research has investigated who should perform the drawing.

OBJECTIVES

To establish the inter-rater reliability of pain extent and location derived from three sets of pain drawings for people with chronic low back pain: one self-reported and two clinician-reported. Additionally, convergent validity of pain extent was assessed using the same dataset.

DESIGN

Repeated-measures cross-sectional study.

METHOD

Fifteen patients with chronic low back pain and a pool of eight clinicians were involved to assess the reliability of pain extent and location extracted by self-report and clinician-reported pain drawings. Inter-rater reliability of pain extent was computed using intraclass correlation coefficients (ICC) and Bland Altman analysis. Convergent validity of pain extent was assessed using Spearman's rank correlation. Inter-rater reliability of pain location was assessed using the Jaccard similarity index.

RESULTS

The inter-reliability analysis for pain extent, derived from self-reported and clinician-reported pain drawings, revealed ICC scores ranging from 0.39 to 0.51, all with wide confidence intervals. The mean Jaccard similarity indexes computed for pain location ranged from 0.60 to 0.65. Moderate to good correlation was found for pain extent derived by the sets of pain drawings.

CONCLUSIONS

Inter-rater reliability of pain extent and pain location derived from self-reported and clinician-reported pain drawings is poor in patients with chronic low back pain. The lack of reliability is also confirmed when considering only clinician-reported PDs. The convergent validity analysis of pain extent revealed that the two pain drawing approaches measure a similar construct.

Measurement properties of cervical joint position error in people with and without chronic neck pain

BACKGROUND

People with chronic neck pain (CNP) often present with impaired neck proprioception. The most widely used clinical test for assessing neck proprioception is cervical joint position sense which measures joint position error (JPE). This clinical test is typically performed using a laser pointer to examine the accuracy of returning to a neutral head position (NHP) or target head position (THP) following active neck movements. The aim of this study was to determine the measurement properties of JPE using a laser pointer when tested in people with and without CNP under a variety of different testing conditions (i.e., different movement directions, sitting versus standing, NHP versus THP).

METHODS

Forty-three participants (23 asymptomatic and 20 with CNP) underwent neck proprioception testing, returning to a NHP and THP in both sitting and standing positions (six trials for each test). A laser pointer was secured on the participant's forehead and inertial measurement unit (IMU) sensors were placed beneath the laser pointer and at the level of the spinous process of the seventh cervical vertebra. Both the absolute and the constant JPE were assessed.

FINDINGS

For the asymptomatic participants, good reliability (ICC: 0.79) was found only for right rotation of the THP task in sitting. In standing, good reliability (ICC: 0.77) was only found in flexion for the THP task. In standing, good reliability (ICC: 0.77) was only found for right rotation of the THP for the absolute JPE and left rotation (ICC: 0.85) for the constant error of the NHP task. In those with CNP, when tested in sitting, good reliability was found for flexion (ICC: 0.8) for the absolute JPE and good reliability (ICC range: 0.8-0.84) was found for flexion, extension, and right rotation for the constant JPE. In standing, good reliability (ICC range: 0.81-0.88) was found for flexion, and rotation for the absolute JPE. The constant JPE showed good reliability (ICC: 0.85) for right rotation and excellent reliability (ICC: 0.93) for flexion. Validity was weak to strong (r range: 0.26-0.83) and moderate to very strong (r range: 0.47-0.93) for absolute and constant error respectively, when tested in sitting. In standing, the validity was weak to very strong (0.38-0.96) for the absolute JPE and moderate to very strong (r range: 0.54-0.92) for the constant JPE.

CONCLUSION

The reliability of the measure of JPE when tested in sitting and standing in both groups showed good reliability, but not for all movements. The results of the current study also showed that the laser pointer correlated well with the Noraxon IMUs, but not for all movements. The results of the current study support the use of the JPE using a laser pointer in clinical and research settings.

Measurement properties of a computer adaptive device, the Senscoordination 3D Cervical Trainer, to assess cervical range of motion in people with neck pain

INTRODUCTION

Clinicians commonly assess cervical range of motion (ROM) in patients with neck pain. Recently, a new instrument has been developed, the Senscoordination 3D Cervical Trainer (SCT), designed to measure neck ROM in addition to joint position error, static and dynamic balance performance, and performance on a 'neuro muscular control test'. This study aims to assess the interrater reliability, concurrent validity, and responsiveness of the SCT using the CROM device as a comparator.

METHODS

One hundred patients with non-specific neck pain were included and their active cervical ROM was measured in a random order by two raters in succession using both devices simultaneously at baseline and after personalised physiotherapy management, at 12 week follow up. Convergent validity and responsiveness were quantified by a Pearson correlation coefficient. The intraclass correlation coefficient (ICC) was used to calculate the test-retest reliability of the SCT. The smallest detectable change (SDC) was calculated per movement direction and for the total range of motion.

RESULTS

The correlation between the measures obtained with the CROM device and the SCT was high (0.97 or 0.98 depending on direction of movement). Interrater reliability was high for all directions (ICC ranging from 0.81 to 0.97). The SDC ranged from 6.9 for left cervical rotation to 12.2 for right cervical rotation. At the follow up, correlation between the change score on the CROM device and the SCT was high (0.86-0.94 depending on the direction of movement).

CONCLUSION

The SCT is a valid, reliable and responsive instrument for measuring cervical ROM.

Conservative management for lumbar radiculopathy based on the stage of the disorder: a Delphi study

PURPOSE

Conservative management of lumbar radiculopathy (LR) is the first treatment option. To date, systematic reviews and clinical practice guidelines have not considered the most appropriate timing of management. This study aimed to establish consensus on effective conservative treatment modalities across different stages (i.e., acute, sub-acute, or chronic) of LR.

MATERIALS AND METHODS

Through an iterative multistage Delphi process, experts rated agreement with proposed treatment modalities across stages of LR and could suggest additional treatment modalities. The agreement was measured using a 5-point Likert scale. Descriptive statistics were used to measure agreement (median, interquartile ranges, and percentage of agreement). Consensus criteria were defined a priori for each round.

RESULTS

Fourteen panelists produced a consensus list of effective treatment modalities across stages of LR. Acute stage management should focus on providing patients with information about the condition including pain education, individualized physical activity, and directional preference exercises, supported with NSAIDs. In the sub-acute stage, strength training and neurodynamic mobilization could be added and transforaminal/epidural injections considered. In the chronic stage, spinal manipulative therapy, specific exercise, and function-specific physical training should be combined with individualized vocational, ergonomic and postural advice.

CONCLUSIONS

Experts agree effectiveness of interventions differs through the evolution of LR.IMPLICATIONS FOR REHABILITATIONTo date clinical guideline for conservative management of lumbar radiculopathy do not consider the evolution of the condition.Acute stage management of lumbar radiculopathy should focus on providing information about the condition and support individualized physical activity with pain medication.Sub-acute management should add neurodynamic mobilization to strength training, while transforaminal and/or epidural injections could be considered.Chronic stage management should consider spinal manipulative therapy and focus on restoring personalized functional capacity.

Effectiveness of thoracic spine manipulation for upper quadrant musculoskeletal disorders: protocol for a systematic review

INTRODUCTION

Upper quadrant musculoskeletal disorders (UQMD), comprising of cranial, cervical, shoulder and upper extremity disorders, are among the most frequently reported disorders in clinical practice. Thoracic high velocity low amplitude thrust (Tx-HVLAT) manipulation is a form of conservative management recommended in systematic reviews as an effective treatment option for aspects of UQMD disorders such headache, shoulder pain and lateral elbow pain. However, no recent systematic reviews have assessed the effectiveness across UQMD. Therefore, this systematic review aims to update the current evidence on the effectiveness of Tx-HVLAT for patients with UQMD on (1) patient-reported outcomes, (2) performance measures or (3) psychosocial outcomes.

METHODS AND ANALYSIS

The Cochrane Controlled Trials Register, MEDLINE, EMBASE, CINAHL, PEDro and Index to Chiropractic Literature will be searched from inception using Medical Subject Headings (MeSH), Thesaurus and/or free-text words. Combinations will be made based on localisation, disorder, intervention and design. Following guidelines as advised by the Cochrane Back Review Group, published randomised controlled trials will be included. Two review authors will independently assess the risk of bias (ROB) using the Cochrane Back Review Group's recommended ROB2 tool and will independently extract the data using a standardised data extraction form. Overall quality of the evidence will be evaluated using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) method. For continuous data, we will calculate standardised mean differences with 95% CIs. For dichotomous outcomes, relative risks and 95% CIs will be calculated. Where possible we will present a subgroup analysis by disorder. For pooling, a random-effects model will be used.

ETHICS AND DISSEMINATION

Ethics approval is not required for this systematic review. The study findings will be submitted to a relevant peer-reviewed journal for dissemination and presented at relevant conferences.

PROSPERO REGISTRATION NUMBER

CRD42023429996.

Muscular Adaptations to Concurrent Resistance Training and High-Intensity Interval Training in Adults with Type 2 Diabetes: A Pilot Study

This pilot study aimed to compare the effects of eight weeks of concurrent resistance training (RT) and high-intensity interval training (HIIT) vs. RT alone on muscle performance, mass and quality in adults with type 2 diabetes (T2DM). Twelve T2DM adults were randomly allocated to the RT + HIIT (n = 5) or RT (n = 7) group. Before and after training, maximal oxygen uptake (VO2max), muscle strength and power were evaluated by calorimetry, dynamometry and one-repetition maximum (1RM) test. Quadriceps muscle volume was determined by MRI, and muscle quality was estimated. After RT, VO2max (+12%), knee muscle power (+20%), quadriceps muscle volume (+5.9%) and quality (leg extension, +65.4%; leg step-up, +223%) and 1RM at leg extension (+66.4%), leg step-up (+267%), lat pulldown (+60.9%) and chest press (+61.2%) significantly increased. The RT + HIIT group improved on VO2max (+27%), muscle volume (+6%), muscle power (+9%) and 1RM at lat pulldown (+47%). No other differences were detected. Among groups, changes in muscle quality at leg step-up and leg extension and VO2max were significantly different. The combination of RT and HIIT effectively improves muscle function and size and increases cardiorespiratory fitness in adults with T2DM. However, HIIT combined with RT may interfere with the development of muscle quality.

Pain chronification impacts whole-brain functional connectivity in women with hip osteoarthritis during pain stimulation

OBJECTIVE

Previous neuroimaging studies have shown that patients with chronic pain display altered functional connectivity across distributed brain areas involved in the processing of nociceptive stimuli. The aim of the present study was to investigate how pain chronification modulates whole-brain functional connectivity during evoked clinical and tonic pain.

METHODS

Patients with osteoarthritis of the hip (n = 87) were classified into 3 stages of pain chronification (Grades I-III, Mainz Pain Staging System). Electroencephalograms were recorded during 3 conditions: baseline, evoked clinical hip pain, and tonic cold pain (cold pressor test). The effects of both factors (recording condition and pain chronification stage) on the phase-lag index, as a measure of neuronal connectivity, were examined for different frequency bands.

RESULTS

In women, we found increasing functional connectivity in the low-frequency range (delta, 0.5-4 Hz) across pain chronification stages during evoked clinical hip pain and tonic cold pain stimulation. In men, elevated functional connectivity in the delta frequency range was observed in only the tonic cold pain condition.

CONCLUSIONS

Across pain chronification stages, we found that widespread cortical networks increase their synchronization of delta oscillations in response to clinical and experimental nociceptive stimuli. In view of previous studies relating delta oscillations to salience detection and other basic motivational processes, our results hint at these mechanisms playing an important role in pain chronification, mainly in women.

Headache features in people with whiplash associated disorders: A scoping review

BACKGROUND

Whiplash-associated headache (WAH) is one of the most common symptoms after a whiplash injury, leading to high disability. Nevertheless, the clinical characteristics of WAH have not been well described.

OBJECTIVE

To synthesise the existing literature on the clinical characteristics of WAH.

DESIGN

Scoping review.

METHODS

The protocol for this scoping review was registered in Open Science Framework and the PRISMA extension for Scoping Reviews tool was used to ensure methodological and reporting quality. A systematic search was conducted in PubMed, EMBASE, CINAHL, Web of Science and Scopus. The search was performed by one author and the screening of articles was conducted by two authors independently.

RESULTS

A total of 11363 articles were initially identified and finally 26 studies were included in the review. Headache intensity was the most commonly reported feature. Headache duration, frequency and location were also reported in at least four studies. Few studies reported physical impairments that may be related to the presence of WAH. A differentiation with concussion characteristics was only performed in eight studies.

CONCLUSION

WAH appears to be of mild to moderate intensity, typically with episodes of short duration which is commonly experienced in the occipital region amongst other regions, and with a tendency to reduce in intensity over time.

Cervical musculoskeletal impairments and pressure pain sensitivity in office workers with headache

BACKGROUND

Office workers are specifically vulnerable to headache conditions. Neck pain is reported by almost 80% of patients with headaches. Associations between currently recommended tests to examine cervical musculoskeletal impairments, pressure pain sensitivity and self-reported variables in headache, are unknown. The aim of this study is to evaluate whether cervical musculoskeletal impairments and pressure pain sensitivity are associated with self-reported headache variables in office workers.

METHODS

This study reports a cross-sectional analysis using baseline data of a randomized controlled trial. Office workers with headache were included in this analysis. Multivariate associations, controlled for age, sex and neck pain, between cervical musculoskeletal variables (strength, endurance, range of motion, movement control) and pressure pain threshold (PPT) over the neck and self-reported headache variables, such as frequency, intensity, and the Headache-Impact-Test-6, were examined.

RESULTS

Eighty-eight office workers with a 4-week headache frequency of 4.8 (±5.1) days, a moderate average headache intensity (4.5 ± 2.1 on the NRS), and "some impact" (mean score: 53.7 ± 7.9) on the headache-impact-test-6, were included. Range of motion and PPT tested over the upper cervical spine were found to be most consistently associated with any headache variable. An adjusted R2 of 0.26 was found to explain headache intensity and the score on the Headache-Impact-Test-6 by several cervical musculoskeletal and PPT variables.

DISCUSSION

Cervical musculoskeletal impairments can explain, irrespective of coexisting neck pain, only little variability of the presence of headache in office workers. Neck pain is likely a symptom of the headache condition, and not a separate entity.

Headache production during physical examination in patients with and without headache attributed to a whiplash injury: A case-control study

BACKGROUND

Provocation of headache on physical examination of the neck may reflect a role of cervical structures in the presence of acute whiplash-associated headache (WAH).

OBJECTIVE

To determine differences in headache provocation during physical tests in people with and without WAH after a whiplash injury.

DESIGN

Case-control study.

METHODS

Forty-seven people with acute whiplash-associated disorders participated, 28 with WAH. Passive accessory intervertebral movement over the tubercle of C1, the spinous processes of C2-C3 and facet joints of C0-C4, the flexion-rotation test (FRT), manual palpation of cranio-cervical muscles and the upper limb neurodynamic test + cranio-cervical flexion were assessed bilaterally twice by a blinded examiner; headache provocation was determined. Cohen's kappa and Chi-squared were determined to evaluate the intra-rater reliability of test results and differences between groups, respectively. A logistic regression model was also performed.

RESULTS

Intra-rater reliability of headache provocation was good or excellent for most tests. Significant differences between groups were found with higher positive tests in WAH for the assessment of C2 (68%), the most painful side of C0-C1 (57%), C1-C2 (75%) and C2-C3 (53%), most (79%) and least (25%) restricted sides of the FRT, and manual palpation of the most painful side for the trapezius (53%), masseter (50%) and temporalis (46%) muscles. Provocation of headache during the assessment of C2 and C1-C2 on the most painful side demonstrated the highest association with WAH.

CONCLUSION

Mechanical provocation of headache is more frequent in people with WAH than in those without headache soon after a whiplash injury.

Reliability and criterion validity of handheld dynamometry for measuring trunk muscle strength in people with and without chronic non-specific low back pain

BACKGROUND

Evaluating trunk strength is an important aspect of the physical examination of people with low back pain (LBP). Thus, reliable, valid, and easily applied measurement tools are needed to quantify trunk muscle strength and monitor changes in response to interventions.

OBJECTIVES

To determine within-day and between-day test re-test reliability and criterion validity of a handheld dynamometer (HHD) to evaluate maximum isometric trunk strength in people with chronic LBP and asymptomatic individuals.

DESIGN

Reliability and criterion validity study.

METHODS

Twenty adult participants with chronic, non-specific LBP and 35 asymptomatic individuals participated. Isometric trunk flexion, extension, and rotation strength were evaluated with the HHD (Active force 2) and the within-day and between-day reliability were determined with intraclass correlation coefficients (ICC2,1) and the standard error of the measurements (SEM), minimal detectable change (MDC), and the limits of agreement (LOA) using Bland-Altman plots. Criterion validity was evaluated using Pearson correlation coefficients to compare HHD measurements to isokinetic dynamometry for both isometric trunk flexion and extension strength.

RESULTS

Good to excellent within-day and between-day reliability was observed for people with LBP and asymptomatic individuals with (ICC2,1) of 0.73-0.93 and 0.62-0.92 respectively. A moderate to strong correlation was found between measurements with the HHD and the isokinetic dynamometer with a correlation of r = 0.68-0.78 and r = 0.56-0.59 for people with LBP and asymptomatic participants respectively.

CONCLUSION

A HHD is a reliable, valid, and clinically applicable tool for the measurement of trunk strength in adults with and without chronic LBP.

Effects of exercise/physical activity on fear of movement in people with spine-related pain: a systematic review

Background

Kinesiophobia (i.e., fear of movement) can be an important contributor for ongoing pain and disability in people with spine-related pain. It remains unclear whether physical activity interventions/exercise influence kinesiophobia in this population. A systematic review was therefore conducted to synthesize the available evidence on whether physical activity interventions/exercise influence kinesiophobia in people with chronic non-specific spine-related pain.

Methods

The study protocol was registered prospectively with PROSPERO (CRD42021295755). The following databases were systematically searched from inception to 31 January 2022 and updated on 22 June 2023: PubMed, MEDLINE, Embase, CINAHL, Web of Science, PsycINFO, ZETOC, PROSPERO and Google Scholar. Inclusion criteria were randomized or non-randomized controlled studies investigating adults aged ≥18 years, reporting the effect of exercise or physical activity on kinesiophobia in individuals with chronic non-specific spine-related pain. Two reviewers independently extracted data and assessed the quality of the included studies. Bias was assessed using the Cochrane ROB2 tool and evidence certainty via Grading of Recommendations Assessment, Development and Evaluation (GRADE).

Results

Seventeen studies from seven countries involving a total of 1,354 individuals were selected for inclusion. The majority of studies (n = 13) involved participants with chronic low back pain (LBP), and Pilates was the most common form of exercise evaluated. Most of the studies reported a positive direction of effect in favor of exercise reducing kinesiophobia when compared to a control group. There was moderate to high risk of bias among the studies and the overall certainty of the evidence was very low.

Conclusion

This review supports the use of exercise for reducing kinesiophobia in people with chronic LBP albeit with very low certainty of evidence; Pilates (especially equipment-based) was shown to be effective as were strengthening training programmes. There was limited evidence available on the effects of exercise on kinesiophobia for people with chronic neck or thoracic pain and further research is required.

Systematic review registration

https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=295755.

External validation of a clinical prediction tool for the use of manual therapy for patients with temporomandibular disorders: a protocol for a prospective observational study

INTRODUCTION

Clinical guidelines recommend conservative treatment for the management of temporomandibular disorders (TMD), and manual therapy directed to temporomandibular structures is commonly applied to reduce pain and improve function. In a recent prospective study, we developed a clinical prediction tool based on an array of predictors to identify people with TMD who are likely to experience significant pain relief and functional improvements following a programme of manual therapies (MTP) applied to temporomandibular structures. The purpose of this study is to externally validate in a different sample (temporal validation) the prediction model obtained in the initial study.

METHODS/ANALYSIS

This observational prospective study will recruit a cohort of 120 adults with TMD from a Dental Hospital in Italy. The intervention will be an MTP consisting of four sessions (once per week) of manual therapy applied to temporomandibular structures. Candidate predictors included in the predictive model will be pain intensity during mouth opening, treatment expectations, number of pain locations, central sensitisation, TMD pain duration and maximal mouth opening. Outcome measures (i.e., pain intensity, functional improvement) will be collected before starting the MTP, after the last session and after 1 month (2 months from baseline). A reduction of pain intensity by at least 30% will be considered a good outcome. External validity of the prediction model will be evaluated after the last session by measuring its calibration, discrimination and overall fit. Additionally, the performance of the model will be evaluated considering the clinical outcomes collected 1 month after the last MTP session.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the Ethics Committee of the Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Italy. The results will be submitted for publication in a peer-reviewed journal, and the prediction model will be implemented in a web-based calculator to facilitate its use by clinicians.

TRIAL REGISTRATION NUMBER

NCT03990662.

Can baseline features predict a reduction in pain and disability following neck-specific exercise in people with chronic non-specific neck pain?: A systematic review and meta-analysis protocol

INTRODUCTION

Neck-specific exercises (NSEs) are commonly used for the treatment of chronic non-specific neck pain (CNSNP). However, it remains unclear whether baseline features can predict the response to neck-specific exercise (NSE) in people with CNSNP. This systematic review aims to assess whether baseline features such as age, gender, muscle activity, fatigability, endurance and fear of movement can predict pain and disability reduction following a NSE intervention.

METHODS AND ANALYSIS

This systematic review and meta-analysis will be reported in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Protocols guidelines checklist. The Web of Science, PubMed, Scopus, MEDLINE, Embase and CINAHL databases; key journals; and grey literature will be searched up until June 2023, including medical subject heading terms and keywords combinations. Included studies will investigate an association between the baseline features and pain and disability outcomes following NSE in people with CNSNP. Two independent reviewers will oversee the searching, screening, data extraction and assessment of risk of bias. The risk of bias will be assessed using the Risk Of Bias In Non-randomised Studies of Interventions (ROBINS-I) and Risk-Of-Bias tool for randomised trials 2 (ROB 2). The quality of evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach (GRADE). Using standardised forms, details regarding study characteristics, baseline features (predictive factors), intervention, primary outcome and effect size (OR and 95% CI of each predictive factor and p value) will be extracted from included studies. Meta-analyses will be considered, if the studies are sufficiently homogeneous and if three or more studies investigate the same or comparable factors that predict the same response (pain intensity or disability). In the event that less than three studies investigated the same factors, a narrative synthesis will be conducted.

ETHICS AND DISSEMINATION

Ethical approval will not be required as this review will be based on published studies. The results of this study will be submitted to a peer-reviewed journal and presented at conferences.

PROSPERO REGISTRATION NUMBER

CRD42023408332.

Predictors of poor outcome following lumbar spinal fusion surgery: a prospective observational study to derive two clinical prediction rules using British Spine Registry data

PURPOSE

Lumbar spinal fusion surgery (LSFS) is common for lumbar degenerative disorders. The objective was to develop clinical prediction rules to identify which patients are likely to have a favourable outcome to inform decisions regarding surgery and rehabilitation.

METHODS

A prospective observational study recruited 600 (derivation) and 600 (internal validation) consecutive adult patients undergoing LSFS for degenerative lumbar disorder through the British Spine Registry. Definition of good outcome (6 weeks, 12 months) was reduction in pain intensity (Numerical Rating Scale, 0-10) and disability (Oswestry Disability Index, ODI 0-50) > 1.7 and 14.3, respectively. Linear and logistic regression models were fitted and regression coefficients, Odds ratios and 95% CIs reported.

RESULTS

Lower BMI, higher ODI and higher leg pain pre-operatively were predictive of good disability outcome, higher back pain was predictive of good back pain outcome, and no previous surgery and higher leg pain were predictive of good leg pain outcome; all at 6 weeks. Working and higher leg pain were predictive of good ODI and leg pain outcomes, higher back pain was predictive of good back pain outcome, and higher leg pain was predictive of good leg pain outcome at 12 months. Model performance demonstrated reasonable to good calibration and adequate/very good discrimination.

CONCLUSIONS

BMI, ODI, leg and back pain and previous surgery are important considerations pre-operatively to inform decisions for surgery. Pre-operative leg and back pain and work status are important considerations to inform decisions for management following surgery. Findings may inform clinical decision making regarding LSFS and associated rehabilitation.

Is movement variability altered in people with chronic non-specific low back pain? A systematic review

BACKGROUND

Variability in spine kinematics is a common motor adaptation to pain, which has been measured in various ways. However, it remains unclear whether low back pain (LBP) is typically characterised by increased, decreased or unchanged kinematic variability. Therefore, the aim of this review was to synthesise the evidence on whether the amount and structure of spine kinematic variability is altered in people with chronic non-specific LBP (CNSLBP).

METHODS

Electronic databases, grey literature, and key journals were searched from inception up to August 2022, following a published and registered protocol. Eligible studies must investigated kinematic variability in CNSLBP people (adults ≥18 years) while preforming repetitive functional tasks. Two reviewers conducted screening, data extraction, and quality assessment independently. Data synthesis was conducted per task type and individual results were presented quantitatively to provide a narrative synthesis. The overall strength of evidence was rated using the Grading of Recommendations, Assessment, Development and Evaluation guidelines.

FINDINGS

Fourteen observational studies were included in this review. To facilitate the interpretation of the results, the included studies were grouped into four categories according to the task preformed (i.e., repeated flexion and extension, lifting, gait, and sit to stand to sit task). The overall quality of evidence was rated as a very low, primarily due to the inclusion criteria that limited the review to observational studies. In addition, the use of heterogeneous metrics for analysis and varying effect sizes contributed to the downgrade of evidence to a very low level.

INTERPRETATION

Individuals with chronic non-specific LBP exhibited altered motor adaptability, as evidenced by differences in kinematic movement variability during the performance of various repetitive functional tasks. However, the direction of the changes in movement variability was not consistent across studies.

Neuromuscular adaptations to experimentally induced pain in the lumbar region: systematic review and meta-analysis

ABSTRACT

Experimental pain models are frequently used to understand the influence of pain on the control of human movement. In this systematic review, we assessed the effects of experimentally induced pain in the lumbar region of healthy individuals on trunk muscle activity and spine kinematics. Databases were searched from inception up to January 31, 2022. In total, 26 studies using either hypertonic saline injection (n = 19), heat thermal stimulation (n = 3), nociceptive electrical stimulation (n = 3), or capsaicin (n = 1) were included. The identified adaptations were task dependent, and their heterogeneity was partially explained by the experimental pain model adopted. Meta-analyses revealed an increase of erector spinae activity (standardized mean difference = 0.71, 95% confidence interval [CI] = 0.22-1.19) during full trunk flexion and delayed onset of transversus abdominis to postural perturbation tasks (mean difference = 25.2 ms, 95% CI = 4.09-46.30) in the presence of pain. Low quality of evidence supported an increase in the activity of the superficial lumbar muscles during locomotion and during voluntary trunk movements during painful conditions. By contrast, activity of erector spinae, deep multifidus, and transversus abdominis was reduced during postural perturbation tasks. Reduced range of motion of the lumbar spine in the presence of pain was supported by low quality of evidence. Given the agreement between our findings and the adaptations observed in clinical populations, the use of experimental pain models may help to better understand the mechanisms underlying motor adaptations to low back pain.

Predictors of Relevant Changes in Pain and Function for Adolescents with Idiopathic Scoliosis following Surgery

STUDY DESIGN

Retrospective analysis of longitudinal data.

OBJECTIVE

To evaluate clinically relevant change in surgical outcomes for Adolescents with Idiopathic Scoliosis (AIS), comparing those who achieved smallest detectable change (SDC) in pain and function at 1-year post-surgery and those who did not, and to evaluate the influencing factors.

SUMMARY OF BACKGROUND DATA

The SDC is recommended to evaluate the surgical outcomes of AIS. However, little is known about the use of SDC in AIS and its influencing factors.

METHODS

This was a retrospective analysis of longitudinal data from patients who underwent surgical correction at a tertiary spinal centre from to 2009-2019. Surgical outcomes were assessed at short-term (6 wk, 6 mo) and long-term (1- and 2-years) post-surgery using the Scoliosis Research Society (SRS-22r). The difference between 'successful' (≥ SDC) and 'unsuccessful' (< SDC) groups was assessed using an independent t-test. Univariate and logistic regression analyses enabled the assessment of influencing factors.

RESULTS

All SRS-22r domains decreased in the short term, except for self-image and satisfaction. In the long term, self-image increased by 1.21 and function increased by 0.2, and pain decreased by 0.1. In all SRS-22r domains 'successful' group had low pre-surgery scores and were statistically different to the 'unsuccessful group'. The difference remained statistically significant at 1-year for most SRS-22r domains. Being older and having low pre-surgery SRS-22r scores increased the chances of achieving SDC function at 1-year. Achieving SDC in the pain domain was significantly associated with age, sex, length of hospital stay, and pre-surgical scores.

CONCLUSION

Notably, the self-image domain showed the largest change compared to other SRS-22r domains. A low preoperative score increases the likelihood of clinical benefit from surgery. These findings demonstrate the utility of SDC for assessing the benefits and factors that may underpin surgical benefit in AIS.

Supervised exercise with or without laser-guided feedback for people with non-specific chronic low back pain. A randomized controlled clinical trial

BACKGROUND

Among the most effective therapeutic interventions in non-specific chronic low back pain (NSCLBP), clinical practice guidelines highlight exercise therapy and patient education; However, regarding the combined intervention of exercise and Pain Neuroscience Education (PNE), there is no consensus on the most effective form of exercise.

OBJETIVE

To find out what changes occurred after the application of two exercise modalities [Supervised Exercise (SE) and Laser-Guided Exercise (LGE)] and PNE on pain, pain pressure thresholds, disability, catastrophizing, kinesiophobia and lumbar proprioception in subjects with NSCLBP.

METHODS

Single-blind randomized clinical controlled trial. 60 subjects with NSCLBP. Both groups performed a a total of 16 therapeutic exercise sessions and 8 Pain Neuroscience Education sessions. With the Laser-Guided Exercise Therapy group performing laser-guided exercises.

RESULTS

A significant decrease was observed for pain intensity for both groups between baseline and post-intervention and the 3 month follow-up (p < 0.001). There was a significant between-group difference between baseline and post-intervention scores in terms of pain intensity and kinesiophobia in favour of the LGE group.

CONCLUSION

Supervised exercise with or without laser feedback, when combined with PNE, reduces pain intensity, disability, pain catastrophizing, kinesiophobia and improves proprioception and PPTs in patients with NSCLBP. At a 3-month follow-up, the combination of LGE plus PNE is most effective for reducing pain intensity.

Comparison between two patient-reported outcome measures for patients with cervical radiculopathy: A think-aloud study

BACKGROUND

The Cervical Radiculopathy Impact Scale (CRIS) and Patient Specific Functional Scale 2.0 (PSFS 2.0) are patient-reported outcome measures (PROMs) used to assess activity limitations in patients with cervical radiculopathy (CR). This study a) compared the CRIS subscale 3 and the PSFS 2.0 in patients with CR with respect to completeness and patient preference, b) established the correlation between both PROMs in assessing the individual patient's level of functional limitations and c) assessed the frequency of reported functional limitations.

METHODS

Participants with CR participated in semi-structured, individual, face-to-face interviews as part of a "think-aloud" process; verbalising their thoughts while completing both PROMs. Sessions were digitally recorded and transcribed verbatim for analysis.

RESULTS

Twenty-two patients were recruited. The most frequently reported functional limitation on the CRIS was: 'working at a computer' (n = 17) and overhead activities' (n = 10) for the PSFS 2.0. There was significant moderate positive correlation between the scores on the PSFS 2.0 and the CRIS (Spearman's r = 0.55, n = 22 p = .008). Most patients (n = 18; 82%) preferred the ability to present their own individual functional limitations of the PSFS 2.0. Eleven participants (50%) preferred the 11-point scale of the PSFS 2.0 over the 5-point Likert scale scoring option of the CRIS.

CONCLUSION

Both easy to complete PROMs capture functional limitations in patients with CR. Most patients prefer the PSFS 2.0 over the CRIS. The wording and layout of both PROMs need refinement to enhance user-friendliness and avoid misinterpretation.

A network analysis on biopsychosocial factors and pain-related outcomes assessed during a COVID-19 lockdown

Psychological stress, social isolation, physical inactivity, and reduced access to care during lockdowns throughout a pandemic negatively impact pain and function. In the context of the first COVID-19 lockdown in Spain, we aimed to investigate how different biopsychosocial factors influence chiropractic patients' pain-related outcomes and vice-versa. A total of 648 chiropractic patients completed online questionnaires including variables from the following categories: demographics, pain outcomes, pain beliefs, impact of the COVID-19 pandemic, stress/anxiety and self-efficacy. Twenty-eight variables were considered in a cross-sectional network analysis to examine bidirectional associations between biopsychosocial factors and pain outcomes. Subgroup analyses were conducted to estimate differences according to gender and symptom duration. The greatest associations were observed between pain duration and pain evolution during lockdown. Participants' age, pain symptoms' evolution during lockdown, and generalized anxiety were the variables with the strongest influence over the whole network. Negative emotions evoked by the pandemic were indirectly associated with pain outcomes, possibly via pain catastrophizing. The network structure of patients reporting acute pain showed important differences when compared to patients with chronic pain. These findings will contribute to identify which factors explain the deleterious effects of both the pandemic and the restrictions on patients living with pain.

Physical testing in patients with acute whiplash-associated disorders: A within session test-retest reliability study

BACKGROUND

People with whiplash-associated disorders (WAD) commonly present with a variety of physical impairments. However, the reliability of physical tests has not been established for patients with acute WAD.

OBJECTIVE

To assess test-retest reliability of different physical tests in acute WAD.

DESIGN

Intra-rater test-retest reliability.

METHODS

Patients with acute WAD were recruited. Physical tests were used to evaluate articular, muscular and neural systems in two blocks of measurements separated by 10 min. Bland-Altman plots were performed to assess intrarater agreement, which included calculation of the mean difference (d) between rates, the 95% CI for d, the standard deviation of the differences and the 95% limits of agreement. Reliability was calculated via the standard error of measurement, the minimal detectable change, percent of agreement, the intraclass-correlation coefficient, and kappa coefficient.

RESULTS

47 patients participated. Test-retest reliability was excellent or good for almost all measures, except for extension ROM, ULTT for the radial nerve, and active cervical extension and upper cervical rotation performed in 4-point kneeling, which presented moderate reliability. Systematic bias was found in cervical ROM in flexion, left and right lateral-flexion, left and right rotation; left ULTT for radial nerve; right trapezius, suboccipitalis and temporalis muscles, left temporalis; C3, both sides of C1-C2, left C3-C4.

CONCLUSION

The majority of physical tests achieved good or excellent test-retest intra-rater reliability when tested in patients with acute WAD. Findings must be considered with caution for those tests which demonstrated systematic bias. Additional research is warranted to evaluate inter-rater reliability.

Measuring complexity of muscle force control: Theoretical principles and clinical relevance in musculoskeletal research and practice

Musculoskeletal conditions affect bones, joints, and muscles of the locomotor system and are a leading cause of disability worldwide. This suggests that current musculoskeletal rehabilitation techniques fail to target the characteristics (e.g., physiological/physical/psychological) most influential for long-term musculoskeletal health. To identify whether a physiological characteristic is impaired, it must be measured. In neuromuscular control, traditional research approaches use magnitude-based measurements (e.g., peak force/standard deviation of force/coefficient of variation of force). However, magnitude-based measurements miss 'hidden information' regarding a physiological system's status across time. To better identify physiological characteristics that are clinically-important for long-term musculoskeletal health, other measurement approaches currently less applied in musculoskeletal research may be helpful. The purpose of this article is to present an introduction to technical and measurement principles for quantifying the 'complexity' of muscle force control as one representation of peripheral joint neuromuscular control. Complexity measurements are time-based and consider the irregular temporal structure of physiological signals. We review theoretical principles underlying measuring complexity of muscle force control and explain its clinical relevance for musculoskeletal scientists and clinicians. The principles include sensorimotor control of peripheral joints, muscle force signal construction and features, muscle force control measurement procedures, and variability and complexity variables. We propose the potential utility of measuring the complexity of muscle force control for diagnosing sensorimotor system impairment and prognosis following musculoskeletal disease or injury. This article will serve as an educational asset and a scientific resource that will inform future research directions to optimise rehabilitation for people with peripheral joint disease and injury.

Consensus for experimental design in electromyography (CEDE) project: Single motor unit matrix

The analysis of single motor unit (SMU) activity provides the foundation from which information about the neural strategies underlying the control of muscle force can be identified, due to the one-to-one association between the action potentials generated by an alpha motor neuron and those received by the innervated muscle fibers. Such a powerful assessment has been conventionally performed with invasive electrodes (i.e., intramuscular electromyography (EMG)), however, recent advances in signal processing techniques have enabled the identification of single motor unit (SMU) activity in high-density surface electromyography (HDsEMG) recordings. This matrix, developed by the Consensus for Experimental Design in Electromyography (CEDE) project, provides recommendations for the recording and analysis of SMU activity with both invasive (needle and fine-wire EMG) and non-invasive (HDsEMG) SMU identification methods, summarizing their advantages and disadvantages when used during different testing conditions. Recommendations for the analysis and reporting of discharge rate and peripheral (i.e., muscle fiber conduction velocity) SMU properties are also provided. The results of the Delphi process to reach consensus are contained in an appendix. This matrix is intended to help researchers to collect, report, and interpret SMU data in the context of both research and clinical applications.

A randomized controlled trial on the effects of "Global Postural Re-education" versus neck specific exercise on pain, disability, postural control, and neuromuscular features in women with chronic non-specific neck pain

BACKGROUND

Neck pain is associated with decreased health-related quality of life, decreased work productivity, and increased visits to health care providers.

AIM

The aim of this study was to assess the effectiveness of "Global Postural Re-education" (GPR) versus a neck specific exercise (SE) program on neck pain, disability, cervical range of movement, postural stability, and activity of the superficial cervical flexor muscles.

DESIGN

A parallel-group and single-blinded clinical trial.

SETTING

Community interventions.

POPULATION

Fifty women with non-specific chronic neck pain (NSCNP).

METHODS

Participants were randomly assigned to one of the two intervention groups (GPR [N.=25] or SE [N.=25]). Both interventions consisted of eight sessions of ~40 minutes duration, performed twice a week, for four weeks. Outcomes included neck pain intensity and disability, cervical range of motion (CROM), postural sway, and activity of the superficial neck flexor muscles during a cranio-cervical flexion test (CCFT). All outcomes were assessed twice before the intervention and immediately following eight treatment sessions over four weeks.

RESULTS

Both interventions were equally effective in reducing neck pain (P<0.001, ŋp²=0.770) and disability (P<0.001, ŋp²=0.306), improving neck mobility (P<0.001, 0.385≤ŋp²≤0.623, for all measurements) and decreasing the activity of the superficial cervical flexor muscles (P>0.001). Neither intervention altered postural sway.

CONCLUSIONS

Our results revealed that GPR and SE induced significant positive results in all measures apart from postural stability but with no difference between the interventions.

CLINICAL REHABILITATION IMPACT

"Global Postural Re-education" (GPR) and neck SE interventions are equally effective in reducing neck pain and disability, and improving neck mobility in women with NSCNP. Overall, this study indicates that GPR and SE interventions can be used to effectively manage patients with NSCNP.

The role of post-trauma stress symptoms in the development of chronic musculoskeletal pain and disability: A systematic review

BACKGROUND AND OBJECTIVE

Traumatic injuries are amongst the leading causes of death and disability in the world across all age groups. This systematic review aimed to (1) describe the role of post-traumatic stress symptoms (PTSS) on the development of chronic pain and/or pain-related disability following musculoskeletal trauma and (2) report pain and or pain-related disability by injury severity/type.

DATABASE AND DATA TREATMENT

Electronic databases were searched, from inception to 31 November 2021 and updated on 10 May 2022, to identify studies in which: participants were adults aged ≥16 years sustaining any traumatic event that resulted in one or more musculoskeletal injuries; an outcome measure of PTSS was used within 3 months of a traumatic event; the presence of pain and/or pain-related disability was recorded at a follow-up of 3 months or more. Two reviewers independently screened papers and assessed the quality of included studies.

RESULTS

Eight studies were included. Owing to between-study heterogeneity, the results were synthesized using a narrative approach. Five studies investigated the relationship between PTSS and pain. Participants with PTSS were more likely to develop persistent pain for at least 12 months post-injury. Six studies assessed the relationship between PTSS and pain-related disability. The results suggest that patients with PTSS had significantly higher disability levels for at least 12 months post-injury.

CONCLUSION

Findings from this comprehensive systematic review support a clear relationship between PTSS post-injury and future pain/disability, with the potential importance of certain PTSS clusters (hyper-arousal and numbing).

SIGNIFICANCE

The findings of this systematic review indicate an association between PTSS reported within 3 months of a traumatic musculoskeletal injury and the development of longer-term pain and disability. The PTSS clusters of 'hyper-arousal' and 'numbing' appear to be of particular importance in this relationship.

PROSPERO REGISTRATION NUMBER

CRD42021285243.

Measures of neck muscle strength and their measurement properties in adults with chronic neck pain-a systematic review

BACKGROUND

Measurement of neck muscle strength is common during the assessment of people with chronic neck pain (CNP). This systematic review evaluates the measurement properties (reliability, validity, and responsiveness) of neck muscle strength measures in people with CNP.

DATABASES AND DATA TREATMENT

This systematic review followed a PROSPERO registered protocol (CRD42021233290). Electronic databases MEDLINE (OVID interface), CINAHL, SPORTDiscuss via (EBSCO interface), EMBASE (OVID interface), and Web of Science were searched from inception to 21 June 2021. Screening, data extraction, and quality assessment (Consensus-based Standards for the selection of Health Measurement Instruments (COSMIN) checklist) were conducted independently by two reviewers. The overall strength of evidence was evaluated using the modified Grading of Recommendations Assessment, Development and Evaluation.

RESULTS

From 794 records, nine articles were included in this review which concerned six different neck strength outcome measures. All studies evaluated reliability and one evaluated construct validity. The reliability of neck strength measures ranged from good to excellent. However, the risk of bias was rated as doubtful/inadequate for all except one study and the overall certainty of evidence was rated low/very low for all measures except for the measurement error of a handheld dynamometer.

CONCLUSION

A multitude of measures are used to evaluate neck muscle strength in people with CNP, but their measurement properties have not been fully established. Further methodologically rigorous research is required to increase the overall quality of evidence.

Determining the level of cervical radiculopathy: Agreement between visual inspection of pain drawings and magnetic resonance imaging

BACKGROUND AND AIMS

Pain drawings are commonly used in the clinical assessment of people with cervical radiculopathy. This study aimed to assess (1) the agreement of clinical interpretation of pain drawings and MRI findings in identifying the affected level of cervical radiculopathy, (2) the agreement of these predictions based on the pain drawing among four clinicians from two different professions (i.e., physiotherapy and surgery) and (3) the topographical pain distribution of people presenting with cervical radiculopathy (C4-C7).

METHODS

Ninety-eight pain drawings were obtained from a baseline assessment of participants in a randomized clinical trial, in which single-level cervical radiculopathy was determined using MRI. Four experienced clinicians independently rated each pain drawing, attributing the pain distribution to a single nerve root (C4-C7). A post hoc analysis was performed to assess agreement.

OUTCOME MEASURES

Percentage agreement and kappa values were used to assess the level of agreement. Topographic pain frequency maps were created for each cervical radiculopathy level as determined by MRI.

RESULTS

The radiculopathy level determined from the pain drawings showed poor overall agreement with MRI (mean = 35.7%, K = -0.007 to 0.139). The inter-clinician agreement ranged from fair to moderate (K = 0.212-0.446). Topographic frequency maps revealed that pain distributions were widespread and overlapped markedly between patients presenting with different levels cervical radiculopathy.

CONCLUSION

This study revealed a lack of agreement between the segmental level affected determined from the patient's pain drawing and the affected level as identified on MRI. The large overlap of pain and non-dermatomal distribution of pain reported by patients likely contributed to this result.

Content validity of the Scoliosis Research Society questionnaire (SRS-22r): A qualitative concept elicitation study

INTRODUCTION

Scoliosis Research Society-22 revised (SRS-22r) is the common questionnaire used to evaluate health related quality of life (HRQOL) for young people with adolescent idiopathic scoliosis (AIS). The aim of this study is to evaluate its content validity for this population.

METHODS

In-depth semi-structured interviews were conducted with a purposive sample of young people with AIS (Cobb angle ≥25˚, aged 10-18 years). Concept elicitation was used to evaluate the influence of AIS on participants' HRQOL. Participant information sheets and consent/assent forms were age relevant. Topic guide was informed by the SRS-22r and existing evidence. Interviews were audio and video recorded, transcribed verbatim, coded, and analysed using thematic analysis. Derived themes/codes were compared with SRS-22r contents (domains/items).

RESULTS

Eleven participants (mean age 14.9 years [SD = 1.8]; 8 female) were recruited. The mean curve size was 47.5° [SD = 18°] and participants had been managed via different approaches. Four main themes emerged with associated subthemes: 1) Physical effects related to physical symptoms (back hurt, stiffness) and body asymmetry (uneven shoulders), 2) Activity-related effects showed impact on mobility (sitting for long periods), self-care (dressing), and school activities (focus during lessons), 3) Psychological effects revealed emotional (feel worried), mental (sleep quality), and body image effects (hide back from others), 4) Social effects (participation in school and leisure activities), and school, friends and mental health support. A weak association was found between items of the SRS-22r and the identified codes.

CONCLUSION

The SRS-22r does not adequately capture important concepts that relate to HRQOL of adolescents with AIS. These findings support revision of the SRS-22r, or the development of a new patient reported outcome measure to evaluate HRQOL of adolescents with AIS.

Inter-rater reliability, discriminatory and predictive validity of neck movement control tests in office workers with headache and/or neck pain

BACKGROUND

Movement control tests (MCTs) are clinical tests to evaluate impairment of movement and associated neuromuscular control and are commonly used to evaluate people with neck pain or headache conditions. The aim of this study was to establish inter-rater reliability as well as discriminatory and predictive validity for seven MCTs of the upper (UCS) and lower cervical spine (LCS) in office workers with headache or neck pain.

METHODS

Seven MCTs of the UCS (3) and LCS (4) were performed at baseline on 140 office workers which were included in a cluster randomized controlled trial. The occurrences of headache and neck pain were established at baseline (discriminatory validity) and at a 15-month follow-up (predictive validity). Inter-rater-reliability was established in a separate cross-sectional study.

RESULTS

MCTs showed slight to almost perfect inter-rater reliability but limited discriminatory (baseline) and limited to small predictive validity (15-month follow up) for different subgroups of office workers with headache and/or neck pain. MCTs of the UCS showed limited discriminatory validity, especially for rotation in participants with headache and neck pain compared to those with headache only (Negative Likelihood-ratio: 0.82, 95% CI: 0.69-0.98). Participants with neck pain only and ≥1/4 positive MCTs for the sagittal plane had an increased risk for future neck pain (Relative risk: 3.33, 95% CI: 1.05-10.56).

DISCUSSION

MCTs of the UCS and LCS are reliable but have only limited to small validity to predict future headache events in office workers. Insufficient sagittal plane movement control may predict neck pain relapses in the future.

Predictors of pain reduction following a program of manual therapies for patients with temporomandibular disorders: A prospective observational study

BACKGROUND

Clinical guidelines recommend conservative treatment for the management of temporomandibular disorders (TMD), and manual therapy (MT) is commonly applied to reduce pain and improve function.

OBJECTIVES

To identify predictors of pain reduction and functional improvement following a program of manual therapies (MTP) in patients with TMD and develop a first screening tool that could be used in clinical practice to facilitate decision-making.

DESIGN

A cohort of 102 adults with a diagnosis of TMD were treated with four weekly sessions within a MTP applied to craniomandibular structures. Candidate predictors were demographic variables, general health variables, psychosocial features, TMD characteristics and related clinical tests. A reduction of pain intensity by at least 30% after the MTP was considered a good outcome. Logistic regression was adopted to develop the predictive model and its performance was assessed considering the explained variance, calibration, and discrimination. Internal validation of the prediction models was further evaluated in 500 bootstrapped samples.

RESULTS

Patients experiencing pain intensity greater than 2/10 during mouth opening, positive expectations of outcome following a MTP, pain localized in the craniocervical region, and a low Central Sensitization Inventory score obtained a good outcome following the MTP. Predictive performance of the identified physical and psychological variables was characterized by high explained variance (R2 = 58%) and discrimination (AUC = 89%) after internal validation. A preliminary screening clinical tool was developed and presented as a nomogram.

CONCLUSIONS

The high discrimination of the prediction model revealed promising findings, although these need to be externally validated in future research.

TRIAL REGISTRATION NUMBER

NCT03990662.

Measurement of Achilles tendon loading using shear wave tensiometry: A reliability study

BACKGROUND

Shear wave tensiometry is a recent promising technology which can be used to evaluate tendon loading. Knowing the clinimetric features (e.g., reliability) of this technology is important for use in clinical and research settings.

OBJECTIVES

To evaluate the inter-session reliability of a novel shear wave tensiometer for the assessment of Achilles tendon loading. A further aim was to test the construct validity of this device by evaluating its precision in detecting Achilles tendon loading changes induced by a plantar flexor isometric contraction of increasing intensity.

METHOD

Ten healthy participants were recruited. Five measurements were performed at different time points to evaluate inter-session reliability. Shear wave speed along the Achilles tendon was evaluated during different isometric contractions using a shear wave tensiometer composed of an array of four accelerometers fixed on the tendon, ranging from 4 to 8.5 cm from the calcaneal insertion of the tendon. Test-retest, intra- and inter-session reliability were determined using intraclass correlation coefficient (ICC_3.1). Absolute reliability was calculated using the standard error of measurement and minimal detectable change.

RESULTS

Test-retest reliability was good to excellent (ICC_3.1 0.87-0.99) for each of the contraction levels examined. Intra-session reliability was good to excellent (ICC_3.1 0.85-0.96) and inter-session reliability was also good to excellent (ICC_3.1 0.75-0.93) for each of the contraction levels.

CONCLUSIONS

This study confirms the reliability of this novel device. Future studies analyzing participants with Achilles tendinopathy are needed to evaluate the capability of shear wave tensiometry to detect transient changes in loading due to pathology.

Perceived pain and disability but not fear of movement are associated with altered cervical kinematics in people with acute neck pain following a whiplash injury

OBJECTIVES

To determine if measures of cervical kinematics are altered in people with acute whiplash associated disorders (WAD) and secondarily, to examine whether kinematic variables are associated with self-reported outcomes.

METHODS

We recruited people with acute WAD within 15 days after a motor vehicle collision and asymptomatic control participants. All participants performed active neck movements at a self-determined velocity. Maximal range of motion (ROM), peak and mean velocity of movement, smoothness of movement, and cervical joint position error were assessed. Moreover, self-reported measures of perceived pain and disability, pain catastrophising, and fear of movement were obtained.

RESULTS

Sixty people participated: 18 with acute WAD (mean age [SD] 38.7 [12.0]) and 42 as asymptomatic controls (mean age [SD] 38.4 [10.2]). Participants with acute WAD showed significantly decreased ROM in all movement directions (p < 0.0001). All participants with acute WAD showed a reduction in the mean and peak velocity of movement in all directions (p < 0.0001) and the number of velocity peaks was significantly higher (i.e., reduced smoothness of movement) in those with acute WAD in all directions (p < 0.0001). Repositioning acuity following cervical rotation was not significantly different between groups. Neck pain-related disability showed the largest number of significant associations with kinematic features, while fear of movement was not associated with measures of cervical kinematics.

CONCLUSIONS

Participants with acute WAD presented with altered cervical kinematics compared to asymptomatic participants. Several measures of cervical kinematics were associated with the level of pain and disability in people with acute WAD but not their fear of movement.

Modulations in motor unit discharge are related to changes in fascicle length during isometric contractions

The integration of electromyography (EMG) and ultrasound imaging has provided important information about the mechanisms of muscle activation and contraction. Unfortunately, conventional bipolar EMG does not allow an accurate assessment of the interplay between the neural drive received by muscles, changes in fascicle length and torque. We aimed to assess the relationship between modulations in tibialis anterior muscle (TA) motor unit (MU) discharge, fascicle length, and dorsiflexion torque using ultrasound-transparent high-density EMG electrodes. EMG and ultrasound images were recorded simultaneously from TA using a 32-electrode silicon matrix while performing isometric dorsiflexion contractions at two ankle joint positions (0° or 30° plantar flexion) and torques (20% or 40% of maximum). EMG signals were decomposed into MUs and changes in fascicle length were assessed with a fascicle-tracking algorithm. MU firings were converted into a cumulative spike train (CST) that was cross-correlated with torque (CST-torque) and fascicle length (CST-length). High cross-correlations were found for CST-length (0.60, range: 0.31–0.85) and CST-torque (0.71, range: 0.31–0.88). Cross-correlation delays revealed that the delay between CST-fascicle length (∼75 ms) was smaller than CST-torque (∼150 ms, P < 0.001). These delays affected MU recruitment and de-recruitment thresholds since the fascicle length at which MUs were recruited and de-recruited was similar but MU recruitment-de-recruitment torque varied. This study demonstrates that changes in TA fascicle length are related to modulations in MU firing and dorsiflexion torque. These relationships allow assessment of the interplay between neural drive, muscle contraction and torque, enabling the time required to convert neural activity into movement to be quantified.

NEW & NOTEWORTHY By employing ultrasound-transparent high-density EMG electrodes, we show that modulations in tibialis anterior muscle motor unit discharge rate were related to both changes in fascicle length and resultant torque. These relationships permitted the quantification of the relative delays between fluctuations in neural drive, muscle contraction, and transfer of torque via the tendon during sustained isometric dorsiflexion contractions, providing information on the conversion of neural activity into muscle force during a contraction.