Maximal Exercise Tolerance, Objective Trunk Strength, and Mobility Measurements in Axial Spondyloarthritis.

OBJECTIVE: Although exercise therapy is safe, effective, and recommended as a nonpharmacological treatment for axial spondyloarthritis (axSpA), there is a lack of guidelines regarding type and dosage. Insufficient knowledge about physical and physiological variables makes designing effective exercise programs challenging. Therefore, the goal of this study was to simultaneously assess trunk strength, spinal mobility, and the cardiorespiratory fitness of patients with axSpA. METHODS: In a cross-sectional study, 58 patients with axSpA (mean age 40.8 yrs, 50% male, mean symptom duration 10.3 yrs) performed maximal cervical and trunk mobility and isometric strength tests in all planes (using David Back Concept devices) and a maximal cardiopulmonary bicycle exercise test (n = 25). Mobility and strength data were compared to healthy reference data. Cut-off values for clinical cardiopulmonary exercise testing interpretation were used to judge normality. Patients were compared based on radiographic involvement and symptom duration. RESULTS: Both strength (P ≤ 0.02) and mobility (P ≤ 0.001) were significantly lower for the patients with axSpA compared to the reference. Strength deficits were comparable between the radiographic and nonradiographic groups (P > 0.05, except trunk extension [P = 0.03]), whereas mobility showed higher deficits in the radiographic group (cervical extension [P = 0.02] and rotation [P = 0.01], and trunk extension [P = 0.03] and rotation [P = 0.03]), regardless of symptom duration. Similarly, symptom duration positively affected oxygen pulse (P = 0.03), relative anaerobic threshold (P = 0.02), and aerobic capacity (P = 0.02). CONCLUSION: In patients with axSpA, strength is more affected than mobility when compared to healthy controls. Likewise, mainly the metabolic component of aerobic capacity is impaired, affecting cardiopulmonary fitness. These findings indicate that future personalized exercise programs in patients with axSpA should incorporate exercises for cardiopulmonary fitness next to strength and mobility training.

Differences in myoelectric activity of the lumbar muscles between recurrent and chronic low back pain: a cross-sectional study.

BACKGROUND: Altered lower back muscle activity is proposed as a contributing factor to the reoccurrence and chronicity of low back pain (LBP). This study compared lumbar muscle activity during trunk extension in patients with continuous chronic LBP (CLBP), non-continuous CLBP, recurrent LBP (RLBP) and healthy subjects. METHODS: In 75 subjects (16 continuous CLBP, 15 non-continuous CLBP, 23 RLBP, 21 healthy controls), surface electromyographic (EMG) activity of the lumbar erector spinae (ES), multifidus (MF), latissimus dorsi (LD) and gluteus maximus (GM) was recorded during the concentric, holding and eccentric phase of a modified Biering Sorenson exercise. RESULTS: Continuous CLBP patients showed higher EMG activity in the ES and MF muscles compared to healthy controls in the concentric (p = 0.011; p = 0.009 respectively) and the holding phase (p = 0.015; p = 0.013). Higher EMG activity was observed in continuous CLBP compared to RLBP in the ES and MF muscles in the holding phase (p = 0.035; p = 0.037), and in the MF in the concentric phase (p = 0.046), but not in the ES (p = 0.062). No differences in muscle activity were established in either the concentric, holding, and eccentric phase for the LD and GM muscles. No differences were found between non-continuous CLBP and the other groups. CONCLUSIONS: An enhanced muscle activity of the lumbar muscles during the concentric and holding phase was observed during trunk extension in patients with continuous CLBP compared to patients with RLBP and healthy subjects. No differences between groups are present in the GM and LD muscles during concentric and holding phases and for any muscle in the eccentric phase.

Does Pain Neuroscience Education and Cognition-Targeted Motor Control Training Improve Cervical Motor Output? Secondary Analysis of a Randomized Clinical Trial.

BACKGROUND: In the context of interventions aimed at reducing pain, disability, and maladaptive pain cognitions in chronic neck pain, it is hypothesized that patients who have greater symptom reduction possibly also demonstrate greater improvement in cervical motor output. Therefore, the aim of this study was to examine the effect of pain neuroscience education plus cognition-targeted motor control training on cervical motor output. METHODS: Impairments in cervical motor output were measured in 64 subjects with chronic neck pain using standardized tests. Cervical muscle strength, cervical mobility, balance, and cervical neuromuscular control were derived. To assess the differences between groups in response to treatment, a random-intercept linear mixed-models analysis, applying a diagonal covariance matrix, was used. RESULTS: A significant treatment × time interaction effect was found for neuromuscular control of the deep cervical flexors, favoring the experimental treatment at 3 months' follow-up (mean group difference: 1.982; 95% confidence interval 0.779, 3.185; large effect size d = 0.82). Significant main effects of time were found for the neuromuscular capacity of scapulothoracic muscles and for cervical mobility. No significant effects were found for balance, cervical muscle strength, or endurance of cervical flexors. CONCLUSION: Pain neuroscience education combined with cognition-targeted motor control training is not more effective than biomedically focused education and exercise therapy for improving cervical motor output in people with chronic neck pain. Our findings question the relative importance of factors such as pain, disability, and maladaptive pain cognitions on cervical motor output and the need to address it in treatment.

Physical and cognitive exertion do not influence feedforward activation of the trunk muscles: a randomized crossover trial.

Fatigue arises during everyday activities, diminishes movement performance, and increases injury risk. Physical (PE) and cognitive exertion (CE) can induce similar feelings of fatigue, but it is not clear whether these also similarly affect movement performance. Therefore, this study examined the influence of PE and CE on anticipatory postural adjustments (APAs) of trunk muscles, which are feedforward mechanisms that contribute to motor control and controlled movement. Rapid arm movement tasks (RAM) were used to induce APAs of the trunk muscles prior and following three experimental conditions in 20 healthy adults: seated rest without exertion (NE), a combined isometric modified Biering-Sörensen and static abdominal curl to induce PE, and a modified incongruent Stroop colour-word task to induce CE. Fatigue was assessed using self-reported measures, and APA onset latencies of the trunk muscles with surface electromyography. Statistical analyses revealed that neither PE nor CE influence APAs of the trunk. Therefore, it is hypothesized that the influence of fatigue on movement performance might not be through altered motor control, but rather by reduced motivation. However, the possibility that fatigue might influence other mechanisms which contribute to trunk motor control, such as APA amplitude and variability, cannot be excluded and need further examination.

Coronal plane trunk asymmetry is associated with whole-body sagittal alignment in healthy young adolescents before pubertal peak growth.

PURPOSE: To investigate coronal plane trunk asymmetry (TA) and its association with sagittal postural alignment in healthy subjects before pubertal peak growth. METHODS: In this cross-sectional baseline study, 1190 healthy pre-peak growth velocity subjects were included. Coronal plane TA was evaluated using back surface topography. Whole-body sagittal alignment (previously validated and objectively classified as neutral, sway-back or leaning-forward) and sagittal spinopelvic profile (trunk lean, lumbar lordosis, thoracic kyphosis, sacral inclination and length of the posteriorly inclined thoracolumbar segment) were determined, as were height, proportion of trunk to body length, body mass index, generalized joint laxity, and handedness. RESULTS: Logistic regression analysis yielded overall sagittal posture class to be independently associated with coronal plane TA: having a leaning-forward posture associated with a nearly three times higher odds of coronal TA (p < 0.001) compared to neutrals. A sway-back was 2.2 times more likely to show TA (p = 0.016) than a neutral, yet only in boys. Significant associations with coronal TA were also found for trunk lean, thoracic kyphosis and body mass index. These correlations, however, were gender and posture class specific. The spinal region where asymmetry is seen, varies according to the whole-body sagittal alignment type: primary thoracic curves were the most frequent in leaning-forwards, whereas primary curves in the lumbar or declive thoracolumbar segment were the most common in sway-backs. CONCLUSIONS: In immature spines without known scoliosis, coronal plane TA is associated with whole-body sagittal alignment. It is more often seen in non-neutral than neutral sagittal posture types. Whether adolescent idiopathic scoliosis is related with postural characteristics before pubertal growth peak, should be addressed in future prospective studies.

The Impact of a Peer-Tutoring Project on Academic Learning Skills in Speech-Language Pathology Students.

BACKGROUND/AIMS: Peer tutoring may advance learning experiences and academic performances of students. Moreover, it seems to be an effective strategy to develop new skills. This study aimed to explore the effects of peer tutoring on the competencies of first-year students (tutees) and final-year students (tutors) of a master program in speech-language pathology. METHODS: Questionnaires were used to investigate the motivation, expectations, learning success, and competencies of 69 tutees and 32 tutors regarding a peer-tutoring project to optimize the speech sound proficiency skills of the tutees. Their answers were statistically compared with those of a control group of students who did not participate in the peer-tutoring project. RESULTS: Tutees reported a significantly higher learning success compared to the control group, although their motivation and expectations were comparable at the start. The tutors, however, reported little motivation at the start and no improvement at the end of the project. CONCLUSION: Based on the positive effects reported by the tutees, this peer-tutoring program will be integrated in the speech-language training curriculum to improve the speech sound proficiency of first-year students. Nevertheless, adjustments will be needed to decrease the resistance in the final-year tutors. Further research may evaluate the effect of incorporated adjustments on this resistance.

The influence of fatigue and chronic low back pain on muscle recruitment patterns following an unexpected external perturbation.

BACKGROUND: Chronic low back pain (CLBP) has been associated with altered trunk muscle responses as well as increased muscle fatigability. CLBP patients and fatigued healthy subjects could experience similar neuromuscular strategies to attempt to protect the spine. The current study examined muscle activation differences between healthy and CLBP subjects following a perturbation. In addition, the possible role of muscle fatigue was evaluated by investigating the healthy control subjects in a non-fatigued and a fatigued condition. Both experiments were combined to evaluate possible similar strategies between CLBP and fatigued samples. METHODS: Cross-sectional study where 24 CLBP subjects and 26 healthy subjects were evaluated. Both groups (CLBP vs. healthy) and both conditions (non-fatigued and a fatigued condition) were evaluated while a weight was suddenly dropped on a held tray. Erector spinae, multifidus, obliques and biceps brachii were recorded using surface electromyography. Variables describing the bursts timing and variables describing the amount of muscle activity (number of bursts and amplitude increase) post impact were studied. The analysis between groups and conditions was carried out using ANOVAs with repeated measurements for the muscle factor. RESULTS: CLBP subjects reacted similarly to healthy subjects regarding muscle activity post impact. However, the CLBP group showed temporal characteristics of muscle activity that were in between the fatigued and non-fatigued healthy group. Clear differences in muscle activity were displayed for healthy subjects. Fatigued healthy subjects presented more reduced activity after impact (upper limb and trunk muscles) than non-fatigued healthy subjects and different temporal characteristic in the same way than CLBP patients. This same temporal characteristic with CLBP and healthy fatigued people was a delay of the first burst of muscle activity after impact. CONCLUSION: Though similar muscle pattern existed between CLBP and healthy people, CLBP temporal characteristics of muscle activity showed a pattern in between healthy people and fatigued healthy people. While the temporal muscle pattern dysfunction used by CLBP subjects could be related to maladaptive patterns, temporal and muscle activity characteristics used by healthy fatigued people may lead to back injuries.

Determining Predictive Outcome Factors for a Multimodal Treatment Program in Low Back Pain Patients: A Retrospective Cohort Study.

OBJECTIVE: The purpose of this study was to determine the factors predictive of outcomes in a multifaceted rehabilitation program for acute and chronic low back pain (LBP) patients. METHODS: A retrospective cohort study was performed on 565 LBP patients (153 acute and 412 chronic) who participated in a multimodal treatment program at an outpatient clinic in Belgium between 2007 and 2010. The predictive value of several factors, including age, sex, body mass index, fat percentage, Oswestry Disability Index score, Beck Depression Index score, Numeric Pain Rating Scale score for back and leg pain intensity, and Tampa Scale for Kinesiophobia score on favorable treatment outcomes was examined using logistic regression analysis. RESULTS: The results from the multivariate regression indicated that a higher score on the Tampa Scale for Kinesiophobia (odds ratio [OR] = 0.92) decreases the odds of a favorable outcome following a multimodal treatment program in acute LBP. Older age (OR = 0.97), low LBP intensity (OR = 1.191), and higher scores on the Beck Depression Index (OR = 0.96) and the Oswestry LBP Disability Index (OR = 0.93) decreased the odds of a favorable treatment outcome in chronic LBP. CONCLUSIONS: The findings of this study indicate that factors predictive of a (un)favorable treatment outcome differ between acute and chronic LBP. Specifically, kinesiophobia is predictive of poor treatment outcome in acute LBP. In chronic LBP, older age, low LBP intensity, and higher degrees of depression and LBP-related disability are predictive of poor treatment outcome. Therapists should consider assessing these predictive factors at intake to tailor the content of the multimodal treatment program to individual patient needs.

The impact of different lenses on visual and musculoskeletal complaints in VDU workers with work-related neck complaints: a randomized controlled trial.

OBJECTIVES: The impact of wearing lenses on visual and musculoskeletal complaints in VDU workers is currently unknown. The goal of this study was 1) to evaluate the impact of wearing VDU lenses on visual fatigue and self-reported neck pain and disability, compared to progressive lenses, and 2) to measure the effect of both lenses on head inclination and pressure pain thresholds during the performance of a VDU task. METHODS: Thirty-five eligible subjects were randomly assigned to wear progressive VDU lenses (VDU group) (n = 18) or progressive lenses (P group) (n = 17). They were enquired about visual complaints (VFQ), self-perceived pain (NRS) and disability (NDI) at baseline (with old lenses), and 1 week, 3 months and 6 months after wearing their new lenses. In addition, Forward Head Angle (FHA) and PPTs were assessed during and after a VDU task before and 6 months after wearing the new lenses. A short questionnaire concerning the satisfaction about the study lenses was completed at the end of the study. RESULTS: In both groups, visual fatigue and neck pain was decreased at 3 and 6 months follow up, compared to baseline. All PPTs were higher during the second VDU task, independent of the type of lenses. The VDU group reported a significantly higher suitability of the lenses for VDU work. CONCLUSION: It can be concluded that there is little difference in effect of the different lenses on visual and musculoskeletal comfort. Lenses should be adjusted to the task-specific needs and habits of the participant.

The effect of experimental low back pain on lumbar muscle activity in people with a history of clinical low back pain: a muscle functional MRI study.

In people with a history of low back pain (LBP), structural and functional alterations have been observed at several peripheral and central levels of the sensorimotor pathway. These existing alterations might interact with the way the sensorimotor system responds to pain. We examined this assumption by evaluating the lumbar motor responses to experimental nociceptive input of 15 participants during remission of unilateral recurrent LBP. Quantitative T2 images (muscle functional MRI) were taken bilaterally of multifidus, erector spinae, and psoas at several segmental levels (L3 upper and L4 upper and lower endplate) and during several conditions: 1) at rest, 2) upon trunk-extension exercise without pain, and 3) upon trunk-extension exercise with experimental induced pain at the clinical pain-side (1.5-ml intramuscular hypertonic saline injections in erector spinae). Following experimental pain induction, muscle activity levels similarly reduced for all three muscles, on both painful and nonpainful sides, and at multiple segmental levels (P = 0.038). Pain intensity and localization from experimental LBP were similar as during recalled clinical LBP episodes. In conclusion, unilateral and unisegmental experimental LBP exerts a generalized and widespread decrease in lumbar muscle activity during remission of recurrent LBP. This muscle response is consistent with previous observed patterns in healthy people subjected to the same experimental pain paradigm. It is striking that similar inhibitory patterns in response to pain could be observed, despite the presence of preexisting alterations in the lumbar musculature during remission of recurrent LBP. These results suggest that motor output can modify along the course of recurrent LBP.

Multivariable modeling of factors associated with spinal pain in young adolescence.

PURPOSE: To investigate the factors related to the 1-month period prevalence of low back pain (LBP), neck pain (NP) and thoracic spine pain (TSP) in young adolescents, thereby considering potential correlates from the physical, sociodemographic, lifestyle, psychosocial and comorbid pain domains. METHODS: In this cross-sectional baseline study, 69 factors potentially associated with spinal pain were assessed among 842 healthy adolescents before pubertal peak growth. With consideration for possible sex differences in associations, multivariable analysis was used to simultaneously evaluate contributions of all variables collected in the five domains. RESULTS: A significantly higher odds of LBP was shown for having high levels of psychosomatic complaints (odds ratio: 4.4; 95 % confidence interval: 1.6-11.9), a high lumbar lordotic apex, retroversed pelvis, introverted personality, and high levels of negative over positive affect. Associations with a higher prevalence and odds of NP were found for psychosomatic complaints (7.8; 2.5-23.9), TSP in the last month (4.9; 2.2-10.8), backward trunk lean, high levels of negative over positive affect and depressed mood. Having experienced LBP (2.7; 1.3-5.7) or NP (5.5; 2.6-11.8) in the preceding month was associated with a higher odds of TSP, as were low self-esteem, excessive physical activity, sedentarism and not achieving the Fit-norm. CONCLUSIONS: Psychosomatic symptoms and pain comorbidities had the strongest association with 1-month period prevalence of spinal pain in young adolescents, followed by factors from the physical and psychosocial domains. The role that "physical factors" play in non-adult spinal pain may have been underestimated by previous studies.

Disc herniations in astronauts: What causes them, and what does it tell us about herniation on earth?

PURPOSE: Recent work showed an increased risk of cervical and lumbar intervertebral disc (IVD) herniations in astronauts. The European Space Agency asked the authors to advise on the underlying pathophysiology of this increased risk, to identify predisposing factors and possible interventions and to suggest research priorities. METHODS: The authors performed a narrative literature review of the possible mechanisms, and conducted a survey within the team to prioritize research and prevention approaches. RESULTS AND CONCLUSIONS: Based on literature review the most likely cause for lumbar IVD herniations was concluded to be swelling of the IVD in the unloaded condition during spaceflight. For the cervical IVDs, the knowledge base is too limited to postulate a likely mechanism or recommend approaches for prevention. Basic research on the impact of (un)loading on the cervical IVD and translational research is needed. The highest priority prevention approach for the lumbar spine was post-flight care avoiding activities involving spinal flexion, followed by passive spinal loading in spaceflight and exercises to reduce IVD hyper-hydration post-flight.

Optimal Normalization Tests for Muscle Activation of the Levator Scapulae, Pectoralis Minor, and Rhomboid Major: An Electromyography Study Using Maximum Voluntary Isometric Contractions.

OBJECTIVE: To identify maximum voluntary isometric contraction (MVIC) test positions for the deeper-lying scapulothoracic muscles (ie, levator scapulae, pectoralis minor, rhomboid major), and to provide a standard set of a limited number of test positions that generate an MVIC in all scapulothoracic muscles. DESIGN: Cross-sectional study. SETTING: Physical and rehabilitation medicine department. PARTICIPANTS: Healthy subjects (N=21). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Mean peak electromyographic activity from levator scapulae, pectoralis minor, and rhomboid major (investigated with fine-wire electromyography) and from upper trapezius, middle trapezius, lower trapezius, and serratus anterior (investigated with surface electromyography) during the performance of 12 different MVICs. RESULTS: The results indicated that various test positions generated similar high mean electromyographic activity and that no single test generated maximum activity for a specific muscle in all subjects. The results of this study support using a series of test positions for normalization procedures rather than a single exercise to increase the likelihood of recruiting the highest activity in the scapulothoracic muscles. CONCLUSIONS: A standard set of 5 test positions was identified as being sufficient for generating an MVIC of all scapulothoracic muscles: seated T, seated U 135°, prone T-thumbs up, prone V-thumbs up, and supine V-thumbs up. A standard set of test positions for normalization of scapulothoracic electromyographic data that also incorporates the levator scapulae, pectoralis minor, and rhomboid major muscles is 1 step toward a more comprehensive understanding of normal and abnormal muscle function of these muscles and will help to standardize the presentation of scapulothoracic electromyographic muscle activity.

Fiber Typing of the Erector Spinae and Multifidus Muscles in Healthy Controls and Back Pain Patients: A Systematic Literature Review.

OBJECTIVE: Understanding the changes in muscle fiber typing is relevant in the context of muscle disorders because it provides information on the metabolic profile and functional capacity. The aim of this study was to systematically review the literature comparing muscle fiber typing in the back muscles of healthy subjects with low back pain (LBP) patients. METHODS: Predefined keywords regarding muscle fiber typing and back muscles were combined in PubMed and Web of Science electronic search engines from inception to August 2014. Full-text articles were independently screened by 2 independent, blinded researchers. Full texts fulfilling the predefined inclusion criteria were assessed on risk of bias by 2 independent researchers, and relative data were extracted. Data were not pooled because of heterogeneity in biopsy locations and population. RESULTS: From the 214 articles that were identified, 18 met the inclusion criteria. These articles evaluated the muscle fiber type distribution or proportional fiber type area between muscles, muscle layers, men, and women or healthy subjects and LBP patients. Regarding muscle fiber type distribution, findings in healthy subjects and LBP patients show no or inconclusive evidence for intermuscular and interindividual differentiation. Studies evaluating the proportional fiber type area also suggest little intermuscular differentiation but provide plausible evidence that the proportional area occupied by type I fibers is higher in women compared to men. The evidence for differentiation based on the presence of low back pain is conflicting. CONCLUSION: This study found that the evidence regarding muscle fiber typing in back muscles is either inconclusive or shows little differences. The most plausible evidence exists for differentiation in proportional fiber type area depending on sex.

Effect of Pain Induction or Pain Reduction on Conditioned Pain Modulation in Adults: A Systematic Review.

OBJECTIVE: Pain facilitation as well as pain inhibition might be present in chronic pain patients. A decreased efficacy of pain inhibition can be measured by conditioned pain modulation (CPM). The use of the CPM paradigm in scientific research has boosted over the last few years and is recognized for its high clinical relevance in chronic pain patients. It is, however, unclear whether the presence of pain and possible modulations of pain influences the efficacy of endogenous pain inhibition, measured by CPM. This systematic literature study aimed to provide an overview of the effects of clinical pain and experimental pain induction or pain reduction on CPM in adults. METHODS: A systematic literature search was conducted in the databases "Pubmed" and "Web of Science". Only full texts of original studies regarding the effect of clinical pain and experimentally induced pain and pain reduction on CPM in adults were included. The included articles were scored on methodological quality and through a CPM paradigm. RESULTS: Twelve articles of good to moderate quality were included in this review. Some pain inhibitory medication and oral contraceptives inhibit the CPM mechanism. Removing chronic pain by surgery results in an improved CPM response. This effect is not observed when removing acute pain. CONCLUSION: Analgesic medication and oral contraceptives might inhibit the CPM response, whereas there is limited evidence that pain-relieving surgery improves CPM in chronic pain patients. However, the results merely suggest that decreased CPM values (as in chronic pain patients) can improve after elimination of pain.

Classification system of the sagittal standing alignment in young adolescent girls.

PURPOSE: The purpose of this cohort study was to classify sagittal standing alignment of pre-peak height velocity (pre-PHV) girls, and to evaluate whether identified subgroups were associated with measures of spinal pain. This study further aimed at drawing attention to similarities and differences between the current postural classification and a previous system determined among pre-PHV boys. METHODS: 557 pre-PHV girls [mean age, 10.6 years (SD, 0.47 years)] participated in the study. Three gross body segment orientation parameters and five specific lumbopelvic characteristics were quantified during habitual standing. Postural subgroups were determined by cluster analysis. Logistic regression was applied to assess the relationship between postural subgroups and spinal pain measures (pain and seeking care, assessed by self-administered questionnaire). Chi-square statistics, independent samples T test, and distribution-based methods were used for comparison with postural categorization in pre-PHV boys. RESULTS AND CONCLUSION: Among pre-PHV girls, clinically meaningful posture clusters emerged both on the gross body segment and specific lumbopelvic level. The postural subtypes identified among pre-PHV girls closely corresponded to those previously described in pre-PHV boys, thereby allowing the use of the same, working nomenclature. In contrast to previous findings among pre-PHV boys, no associations between posture clusters and spinal pain measures were significant in girls at pre-PHV age. When comparing discrete 'global' alignment scores across corresponding posture types, some intriguing differences were found between genders which might involve different biomechanical loading patterns. Whether habitual posture forms a risk factor for developing spinal pain up to adulthood needs evaluation in prospective multifactorial follow-up research.

Posture class prediction of pre-peak height velocity subjects according to gross body segment orientations using linear discriminant analysis.

BACKGROUND/PURPOSE: Measurement and classification of standing posture in the sagittal plane has important clinical implications for adolescent spinal disorders. Previous work using cluster analysis on three gross body segment orientation parameters (lower limbs, trunk, and entire body inclination) has identified three distinct postural groups of healthy subjects before pubertal peak growth: "neutral", "sway-back", and "leaning-forward". Although accurate postural subgrouping may be proposed to be crucial in understanding biomechanical challenges posed by usual standing, there is currently no objective method available for class assignment. Hence, this paper introduces a novel approach to subclassify new cases objectively according to their overall sagittal balance. METHODS: Postural data previously acquired from 1,196 pre-peak height velocity (pre-PHV) subjects were used in this study. To derive a classification rule for assigning a class label ("neutral", "sway-back", or "leaning-forward") to any new pre-PHV subjects, linear discriminant analysis was applied. Predictor variables were pelvic displacement, trunk lean and body lean angle. The performance of the newly developed classification algorithm was verified by adopting a cross-validation procedure. RESULTS: The statistical model correctly classified over 96.2% of original grouped subjects. In the cross-validation procedure used, over 95.9% of subjects were correctly assigned. CONCLUSIONS: Based on three angular measures describing gross body segment orientation, our triage method is capable of reliably classifying pre-PHV subjects as either "neutral", "sway-back", or "leaning-forward". The discriminant prediction equations presented here enable a highly accurate posture class allocation of new cases with a prediction capability higher than 95.9%, thereby removing subjectivity from sagittal plane posture classification.

Efficacy of a modern neuroscience approach versus usual care evidence-based physiotherapy on pain, disability and brain characteristics in chronic spinal pain patients: protocol of a randomized clinical trial.

BACKGROUND: Among the multiple conservative modalities, physiotherapy is a commonly utilized treatment modality in managing chronic non-specific spinal pain. Despite the scientific progresses with regard to pain and motor control neuroscience, treatment of chronic spinal pain (CSP) often tends to stick to a peripheral biomechanical model, without targeting brain mechanisms. With a view to enhance clinical efficacy of existing physiotherapeutic treatments for CSP, the development of clinical strategies targeted at 'training the brain' is to be pursued. Promising proof-of-principle results have been reported for the effectiveness of a modern neuroscience approach to CSP when compared to usual care, but confirmation is required in a larger, multi-center trial with appropriate evidence-based control intervention and long-term follow-up.The aim of this study is to assess the effectiveness of a modern neuroscience approach, compared to usual care evidence-based physiotherapy, for reducing pain and improving functioning in patients with CSP. A secondary objective entails examining the effectiveness of the modern neuroscience approach versus usual care physiotherapy for normalizing brain gray matter in patients with CSP. METHODS/DESIGN: The study is a multi-center, triple-blind, two-arm (1:1) randomized clinical trial with 1-year follow-up. 120 CSP patients will be randomly allocated to either the experimental (receiving pain neuroscience education followed by cognition-targeted motor control training) or the control group (receiving usual care physiotherapy), each comprising of 3 months treatment. The main outcome measures are pain (including symptoms and indices of central sensitization) and self-reported disability. Secondary outcome measures include brain gray matter structure, motor control, muscle properties, and psychosocial correlates. Clinical assessment and brain imaging will be performed at baseline, post-treatment and at 1-year follow-up. Web-based questionnaires will be completed at baseline, after the first 3 treatment sessions, post-treatment, and at 6 and 12-months follow-up. DISCUSSION: Findings may provide empirical evidence on: (1) the effectiveness of a modern neuroscience approach to CSP for reducing pain and improving functioning, (2) the effectiveness of a modern neuroscience approach for normalizing brain gray matter in CSP patients, and (3) factors associated with therapy success. Hence, this trial might contribute towards refining guidelines for good clinical practice and might be used as a basis for health authorities' recommendations. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02098005.

Biceps femoris and semitendinosus--teammates or competitors? New insights into hamstring injury mechanisms in male football players: a muscle functional MRI study.

BACKGROUND: The hamstring injury mechanism was assessed by investigating the exercise-related metabolic activity characteristics of the hamstring muscles using a muscle functional MRI (mfMRI) protocol. METHODS: 27 healthy male football players and 27 football players with a history of hamstring injuries (recovered and playing fully) underwent standardised mfMR Imaging. The mfMRI protocol consisted of a resting scan, a strenuous bilateral eccentric hamstring exercise and a postexercise scan. The exercise-related T2 increase or the signal intensity shift between both scans was used to detect differences in metabolic activation characteristics (1) between the different hamstring muscle bellies and (2) between the injury group and the control group. RESULTS: A more symmetrical muscle recruitment pattern corresponding to a less economic hamstring muscle activation was demonstrated in the formerly injured group (p<0.05). The injured group also demonstrated a significantly lower strength endurance capacity during the eccentric hamstring exercise. CONCLUSIONS: These findings suggest that the vulnerability of the hamstring muscles to football-related injury is related to the complexity and close coherence in the synergistic muscle recruitment of the biceps femoris and the semitendinosus. Discrete differences in neuromuscular coordination and activity distribution, with the biceps femoris partly having to compensate for the lack of endurance capacity of the semitendinosus, probably increase the hamstring injury risk.