Association Between Symptoms of Central Sensitization and Cognitive Behavioral Factors in People With Chronic Nonspecific Low Back Pain: A Cross-sectional Study.

OBJECTIVE: The objective of this cross-sectional study was to analyze the relationship between symptoms of central sensitization (CS) and important cognitive behavioral and psychosocial factors in a sample of patients with chronic nonspecific low back pain. METHODS: Participants with chronic nonspecific low back pain for at least 3 months were included in the study. They completed several questionnaires and a functional test. Pearson's correlation was used to analyze associations between symptoms of CS and pain behavior, functioning, pain, pain catastrophizing, kinesiophobia, and illness perceptions. Additionally, a between-group analysis was performed to compare patients with and without clinically relevant symptoms of CS. RESULTS: Data from 38 participants were analyzed. Significant associations were found between symptoms of CS and all other outcomes, especially current pain (r = 0.510, P = .001), mean pain during the past 7 days (r = 0.505, P = .001), and pain catastrophizing (r = 0.518, P = .001). Patients with clinically relevant symptoms of CS scored significantly worse on all outcomes compared with persons without relevant symptoms of CS, except on functioning (P = .128). CONCLUSIONS: Symptoms of CS were significantly associated with psychosocial and cognitive behavioral factors. Patients exhibiting a clinically relevant degree of symptoms of CS scored significantly worse on most outcomes, compared with the subgroup of the sample with fewer symptoms of CS.

Auto-Targeted Neurostimulation Is Not Superior to Placebo in Chronic Low Back Pain: A Fourfold Blind Randomized Clinical Trial.

BACKGROUND: Myofascial trigger points (MTrPs) are common in people with musculoskeletal pain and may play a role in chronic nonspecific low back pain (CLBP). One of the potential treatments of MTrPs is the Nervomatrix Soleve® auto-targeted neurostimulation device, providing targeted transcutaneous electrical nerve stimulation (TENS) to MTrPs in the lower back muscles. To date, no controlled studies have evaluated the effectiveness of this device for the pain management of this population. OBJECTIVE: To examine whether the Nervomatrix Soleve® auto-targeted neurostimulation device is superior over placebo for the treatment of CLBP. STUDY DESIGN: A fourfold-blind randomized controlled trial was conducted. SETTING: Brussels University Hospital, health care centers and pharmacies around Belgium. METHODS: Participants with CLBP for at least 3 months were randomly assigned to the experimental (the Nervomatrix Soleve® auto-targeted neurostimulation device providing TENS-stimulation and mechanical pressure) or placebo group (the Nervomatrix Soleve® auto-targeted neurostimulation device providing mechanical pressure alone without current). The treatment protocol in both groups consisted of 6 treatment sessions per patient. Participants were evaluated at baseline prior to the intervention, immediately following treatment, and at one month follow-up. Pain and pain behavior (steps climbed) were assessed as primary outcome measures. Secondary outcome measures were pain functioning, health beliefs, symptoms of central sensitization, pain catastrophizing, and kinesiophobia. RESULTS: In total, 39 participants were included in the study. Participants in both groups improved significantly for pain and functioning, but no significant differences were observed between groups. These improvements were not clinically meaningful for any of the reported measures. The health beliefs changed significantly in both groups (P < 0.05), with superior results at follow-up in the placebo group. LIMITATIONS: The follow-up period is limited to one month. CONCLUSIONS: Treatment of MTrPs with the Nervomatrix Soleve® auto-targeted neurostimulation device in patients with CLBP does not result in a better outcome than placebo-treatment in terms of pain, pain behavior, functioning, central sensitization, pain catastrophizing, and health beliefs.

Prevalence, Incidence, Localization, and Pathophysiology of Myofascial Trigger Points in Patients With Spinal Pain: A Systematic Literature Review.

OBJECTIVE: A systematic review was performed to evaluate the existing evidence related to the prevalence, incidence, localization, and pathophysiology of myofascial trigger points (MTrPs) in patients with spinal (back and neck) pain. METHODS: A systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines was performed in 2 electronic databases (PubMed and Web of Science) using predefined keywords regarding MTrPs and spinal pain. A "PICOS" questionnaire was used to set up the search strategies and inclusion criteria. Full-text reports concerning MTrPs in patients with back or neck pain, which described their prevalence, incidence, location, or underlying physiopathology were included and screened for methodological quality by 3 independent researchers. Each study was assessed for risk of bias using a checklist derived from the Web site of the Dutch Cochrane Centre. RESULTS: Fourteen articles were retrieved for quality assessment and data extraction. Studies reporting the incidence of MTrPs in patients with spinal pain were lacking. Within spinal pain, patients with neck pain were found to have the highest prevalence rates of MTrPs. The trapezius descendens, levator scapulae, and suboccipitales muscles were the most prevalent locations for active MTrPs in patients with neck pain. Latent MTrPs were present in asymptomatic people, but no significant differences were found in the prevalence rate of latent MTrPs between patients with spinal (neck) pain and healthy controls. The only study investigating prevalence of MTrPs in different localizations of the same muscle reported no significant differences in prevalence between active and latent MTrPs within the trapezius descendens muscle. Studies examining pathophysiological mechanisms underlying MTrPs demonstrated an acidic environment, high concentration of algogenic/inflammatory substances, stiffer muscle tissue, retrograde diastolic blood flows, spontaneous muscle activity at rest, and loss of muscle contractibility in muscles with MTrPs. Altered central processing was also found to play a role in the development of MTrPs. CONCLUSIONS: Myofascial trigger points are a prevalent clinical entity, especially in patients with neck pain. Evidence was not found to support or deny the role of MTrPs in other spinal pain. Compelling evidence supports local mechanisms underlying MTrPs. Future research should unravel the relevance of central mechanisms and investigate the incidence of MTrPs in patients with spinal pain.

Physical therapists should integrate illness perceptions in their assessment in patients with chronic musculoskeletal pain; a qualitative analysis.

In the past decade, scientific evidence has shown that the biomedical model falls short in the treatment of patients with musculoskeletal pain. To understand musculoskeletal pain and a patient's health behavior and beliefs, physical therapists should assess the illness perceptions of their patients. In this quantitative study, we audiotaped the assessments of 19 primary care physical therapists on 27 patients and analyzed if and how illness perceptions were assessed. The Common Sense Model was used as the theoretical framework. We conclude that some of the domains of the Common Sense Model were frequently asked for (identity, causes and consequences), while others (timeline, treatment control, coherence, emotional representation) were used less frequently or seldom mentioned. The overall impression was that the assessments of the physical therapists were still bio-medically oriented in these patients with chronic musculoskeletal pain.

Dysfunctional pain inhibition in patients with chronic whiplash-associated disorders: an experimental study.

Inefficient endogenous pain inhibition, in particular impaired conditioned pain modulation (CPM), may disturb central pain processing in patients with chronic whiplash-associated disorders (WAD). Previous studies revealed that abnormal central pain processing is responsible for a wide range of symptoms in patients with chronic WAD. Hence, the present study aimed at examining the functioning of descending pain inhibitory pathways, and in particular CPM, in patients with chronic WAD. Thirty-five patients with chronic WAD and 31 healthy controls were subjected to an experiment evaluating CPM. CPM was induced by an inflated occlusion cuff and evaluated by comparing temporal summation (TS) of pressure pain prior to and during cuff inflation. Temporal summation was provoked by means of 10 consecutive pressure pulses at upper and lower limb location. Pain intensity of first, fifth, and 10th pressure pulse was rated. During heterotopic noxious conditioning stimulation, TS of pressure pain was significantly depleted among healthy controls. In contrast, TS was quite similar prior to and during cuff inflation in chronic WAD, providing evidence for dysfunctional CPM in patients with chronic WAD. The present study demonstrates a lack of endogenous pain inhibitory pathways, and in particularly CPM, in patients with chronic WAD, and hence provides additional evidence for the presence of central sensitization in chronic WAD.

Effects of aerobic endurance, muscle strength, and motor control exercise on physical fitness and musculoskeletal injury rate in preprofessional dancers: an uncontrolled trial.

OBJECTIVE: The purpose of this study was to evaluate musculoskeletal injury rate and physical fitness before and 6 months after an endurance, strength, and motor control exercise program in preprofessional dancers. METHODS: This uncontrolled trial was completed at a college offering a professional bachelor degree in dance. Forty preprofessional dancers underwent a test battery before and after a 6-month lasting exercise program in addition to their regular dance lessons. Physical fitness was evaluated by means of a submaximal exercise test with continuous physiological monitoring and by a field test for explosive strength. Anthropometric measurements were taken to analyze the influence of fitness training on body composition. Musculoskeletal injury incidence and quality of life were recorded during the 6-month lasting intervention. An intention-to-treat analysis ("last observation carried forward" method) was used with a Student t test for normally distributed variables. The Wilcoxon signed rank and Mann-Whitney U tests were used as nonparametric tests. RESULTS: Physical fitness improved after the 6 months of additional training program (P<.05). The waist:hip ratio (P=.036) and the sum of the measured subcutaneous skin thickness (P=.001) significantly decreased. Twelve dancers developed musculoskeletal complaints, requiring temporary interruption of dancing. CONCLUSIONS: The combination of regular dance lessons with an additional exercise program resulted in improved physical fitness in preprofessional dancers, without affecting the aesthetical appearance. A relatively high injury rate was observed during the intervention period. These results suggest that a randomized, controlled trial should be performed to examine the effectiveness of additional exercise in dancers on physical fitness and musculoskeletal injury rate.

Treatment of central sensitization in patients with 'unexplained' chronic pain: what options do we have?

INTRODUCTION: Central sensitization accounts for chronic 'unexplained' pain in a wide variety of disorders, including chronic whiplash-associated disorders, temporomandibular disorders, chronic low back pain, osteoarthritis, fibromyalgia, chronic fatigue syndrome and chronic tension-type headache among others. Given the increasing evidence supporting the clinical significance of central sensitization in those with unexplained chronic pain, the awareness is growing that central sensitization should be a treatment target in these patients. AREAS COVERED: This article provides an overview of the treatment options available for desensitizing the CNS in patients with chronic pain due to central sensitization. It focuses on those strategies that specifically target pathophysiological mechanisms known to be involved in central sensitization. In addition, pharmacological options, rehabilitation and neurotechnology options are discussed. EXPERT OPINION: Acetaminophen, serotonin-reuptake inhibitor drugs, selective and balanced serototin and norepinephrine-reuptake inhibitor drugs, the serotonin precursor tryptophan, opioids, N-methyl-d-aspartate (NMDA)-receptor antagonists, calcium-channel alpha(2)delta (a2δ) ligands, transcranial magnetic stimulation, transcutaneous electric nerve stimulation (TENS), manual therapy and stress management each target central pain processing mechanisms in animals that - theoretically - desensitize the CNS in humans. To provide a comprehensive treatment for 'unexplained' chronic pain disorders characterized by central sensitization, it is advocated to combine the best evidence available with treatment modalities known to target central sensitization.

Altered lumbopelvic movement control but not generalized joint hypermobility is associated with increased injury in dancers. A prospective study.

Dancers experience significant more low back pain (LBP) than non-dancers and are at increased risk of developing musculoskeletal injuries. Literature concerning the relationship between joint hypermobility and injury in dancers remains controversial. The purpose of this study was therefore to examine whether lumbopelvic movement control and/or generalized joint hypermobility would predict injuries in dancers. Four clinical tests examining the control of lumbopelvic movement during active hip movements were used in combination with joint hypermobility assessment in 32 dancers. Occurrence of musculoskeletal injuries, requiring time away from dancing, was recorded during a 6-month prospective study. Logistic regression analysis was used to predict the probability of developing lower limb and/or lumbar spine injuries. Twenty-six injuries were registered in 32 dancers. Forty-four percent of the dancers were hypermobile. A logistic regression model using two movement control tests, correctly allocated 78% of the dancers. The results suggest that the outcome of two lumbopelvic movement control tests is associated with an increased risk of developing lower extremities or lumbar spine injuries in dancers. Neither generalized joint hypermobility, evaluated with the Beighton score, nor a history of LBP was predictive of injuries. Further study of these interactions is required.

Low back pain: clinimetric properties of the Trendelenburg test, active straight leg raise test, and breathing pattern during active straight leg raising.

OBJECTIVE: Classification of patients with low back pain (LBP) into subgroups is important as considerable variability exists in the LBP population. Clinical applicable, reliable, and valid tests to differentiate patients with LBP are therefore necessary. The purpose of this study is to examine the reliability, internal consistency, and clinical importance of 3 clinical tests that analyze motor control mechanisms of the lumbopelvic region in patients with nonspecific LBP. METHODS: Thirty-six patients with chronic nonspecific LBP volunteered for the study (cross-sectional design). The patients were examined by 2 assessors who were blinded to the results of each other. The following tests were performed: the Trendelenburg test, the active straight leg raise (ASLR) test, and the ASLR with visual inspection of the breathing pattern. RESULTS: The test-retest reliability coefficients (kappa) were greater than 0.75 for the Trendelenburg score and greater than 0.70 for the ASLR. The interobserver reliability coefficients were greater than 0.39 for the assessment of the breathing pattern during the ASLR. The Cronbach alpha coefficient for internal consistency of the Trendelenburg and ASLR tests was greater than .73. No significant associations were found between the outcome of the tests and self-reported pain severity or disability. CONCLUSIONS: These data provide evidence favoring the test-retest reliability of the Trendelenburg and ASLR tests in patients with LBP. The internal consistency of the outcome of these tests was high for both assessors, suggesting that these tests assess the same dimension. The interobserver reliability of the assessment of the breathing pattern was fair to moderate. Further research regarding the interobserver reliability, clinical importance, validity, and responsiveness of the Trendelenburg test, ASLR test, and breathing pattern during these tests is required.