Outcome measures in chronic low back pain

The purpose of this prospective, single site cohort quasi-experimental study was to determine the responsiveness of the numerical rating scale (NRS), Roland–Morris disability questionnaire (RMDQ), Oswestry disability index (ODI), pain self-efficacy questionnaire (PSEQ) and the patient-specific functional scale (PSFS) in order to determine which would best measure clinically meaningful change in a chronic low back pain (LBP) population. Several patient-based outcome instruments are currently used to measure treatment effect in the chronic LBP population. However, there is a lack of consensus on what constitutes a “successful” outcome, how an important improvement/deterioration has been defined and which outcome measure(s) best captures the effectiveness of therapeutic interventions for the chronic LBP population. Sixty-three consecutive patients with chronic LBP referred to a back exercise and education class participated in this study; 48 of the 63 patients had complete data. Five questionnaires were administered initially and after the 5-week back class intervention. Also at 5 weeks, patients completed a global impression of change as a reflection of meaningful change in patient status. Score changes in the five different questionnaires were subjected to both distribution- and anchor-based methods: standard error of measurement (SEM) and receiver operating characteristic (ROC) curves to define clinical improvement. From these methods, the minimal clinically important difference (MCID) defined as the smallest difference that patients and clinicians perceive to be worthwhile is presented for each instrument. Based on the SEM, a point score change of 2.4 in the NRS, 5 in the RMDQ, 17 in the ODI, 11 on the PSEQ, and 1.4 on the PSFS corresponded to the MCID. Based on ROC curve analysis, a point score change of 4 points for both the NRS and RMDQ, 8 points for the ODI, 9 points for the PSEQ and 2 points for the PSFS corresponded to the MCID. The ROC analysis demonstrated that both the PSEQ and PSFS are responsive to clinically important change over time. The NRS was found to be least responsive. The exact value of the MCID is not a fixed value and is dependent on the assessment method used to calculate the score change. Based on ROC curve analysis the PSFS and PSEQ were more responsive than the other scales in measuring change in patients with chronic LBP following participation in a back class programme. However, due to the small sample size, the lack of observed worsening of symptoms over time, the single centre and intervention studied these results which need to be interpreted with caution.     

Sex differences in predictors of outcome in selected physical therapy interventions for acute low back pain

STUDY DESIGN: Secondary analysis of pooled data from 3 randomized trials. OBJECTIVE: This study investigated sex differences in response to physical therapy intervention for acute low back pain. BACKGROUND: Sex differences in experimental pain sensitivity have been consistently described in the literature. However, clinical consequences of these sex differences have not been widely reported. METHODS AND MEASURES: Subjects (n=165) were participants in 3 randomized trials of physical therapy interventions from outpatient physical therapy clinics in the general and military communities. Subjects were randomly assigned spinal manipulation with range-of-motion exercise, lumbar stabilization exercise, or directional-preference exercise. Outcomes were measured at 4 weeks through self-report of pain intensity and pain-related disability. Sex differences were investigated with independent t tests (baseline data), 2 x 3 analysis of variance (4-week reductions in pain and pain-related disability), and regression models (predictors of outcome). RESULTS: Men and women had similar reductions of pain intensity (raw mean difference, 0.5; 95% Cl, -1.4 to 0.4) and pain-related disability (raw mean difference, 5.3; 95% CI, -0.1 to 10.7) over 4 weeks. Baseline pain intensity, duration of symptoms, and baseline pain-related disability significantly predicted change in pain intensity for women (r2 = 26%, P < .01). Baseline pain intensity and stabilization exercise predicted change in pain intensity for men (r2 = 33%, P<.01). Baseline pain-related disability, duration of pain, and pain intensity predicted change in disability for women (r2 = 24%, P < .01). Baseline pain-related disability, fear-avoidance beliefs, stabilization exercise, and leg pain predicted change in disability for men (r2 = 32%, P < .01). CONCLUSION: For patients with acute low back pain, men and women had similar physical therapy outcomes for reductions in pain intensity and pain-related disability. However, men and women had different factors that predicted treatment outcome.     

Pilates-based therapeutic exercise: effect on subjects with nonspecific chronic low back pain and functional disability: a randomized controlled trial

STUDY DESIGN: A randomized controlled trial, prestest-posttest design, with a 3-, 6-, and 12-month follow-up. OBJECTIVES: To investigate the efficacy of a therapeutic exercise approach in a population with chronic low back pain (LBP). BACKGROUND: Therapeutic approaches developed from the Pilates method are becoming increasingly popular; however, there have been no reports on their efficacy. METHODS AND MEASURES: Thirty-nine physically active subjects between 20 and 55 years old with chronic LBP were randomly assigned to 1 of 2 groups. The specific-exercise-training group participated in a 4-week program consisting of training on specialized (Pilates) exercise equipment, while the control group received the usual care, defined as consultation with a physician and other specialists and healthcare professionals, as necessary. Treatment sessions were designed to train the activation of specific muscles thought to stabilize the lumbar-pelvic region. Functional disability outcomes were measured with The Roland Morris Disability Questionnaire (RMQ/RMDQ-HK) and average pain intensity using a 101-point numerical rating scale. RESULTS: There was a significantly lower level of functional disability (P = .023) and average pain intensity (P = .002) in the specific-exercise-training group than in the control group following the treatment intervention period. The posttest adjusted mean in functional disability level in the specific-exercise-training group was 2.0 (95% CI, 1.3 to 2.7) RMQ/RMDQ-HK points compared to a posttest adjusted mean in the control group of 3.2 (95% CI, 2.5 to 4.0) RMQ/RMDQ-HK points. The posttest adjusted mean in pain intensity in the specific-exercise-training group was 18.3 (95% CI, 11.8 to 24.8), as compared to 33.9 (95% CI, 26.9 to 41.0) in the control group. Improved disability scores in the specific-exercise-training group were maintained for up to 12 months following treatment intervention. CONCLUSIONS: The individuals in the specific-exercise-training group reported a significant decrease in LBP and disability, which was maintained over a 12-month follow-up period. Treatment with a modified Pilates-based approach was more efficacious than usual care in a population with chronic, unresolved LBP.     

Neuromuscular exercises on pain intensity,functional disability,proprioception, and balance of military personnel with chronic low back pain

BackgroundDue to their occupational status, military personnel are a high-risk group for low back pain (LBP).PurposeThe aim of this study was to investigate the effect of neuromuscular exercises on the severity of pain, functional disability, proprioception, and balance in military personnel with LBP.MethodsMilitary personnel with LBP were randomly assigned into two groups: intervention (n=15) and control (n=15). The intervention group performed 60 minutes of neuromuscular exercises three times per week for eight weeks while the control group continued their routine physical activities.ResultsThe mean post-intervention pain intensity, disability, and proprioception error significantly decreased in the intervention group. Whereas their mean post-interventions static and dynamic balance scores significantly increased.ConclusionsThe results indicate eight weeks of neuromuscular exercise decreased pain intensity and improved functional ability, static and dynamic balance, and proprioception among military staff suffering chronic low back pain.     

Role of osteopathic manipulative treatment in altering pain biomarkers: a pilot study

CONTEXT: Underlying mechanisms explaining the effects of osteopathic manipulative treatment (OMT) are poorly defined. The authors evaluate various nociceptive (pain) biomarkers that have been suggested as important mediators in this process. OBJECTIVE: To determine if OMT influences levels of circulatory pain biomarkers. METHODS: In a prospective, blinded assessment, blood was collected from 20 subjects (10 with chronic low back pain [LBP], 10 controls without chronic LBP) for 5 consecutive days. On day 4, OMT was administered to subjects 1 hour before blood collection. Blood was analyzed for levels of beta-endorphin (betaE), serotonin (5-hydroxytryptamine [5-HT]), 5-hydroxyindoleacetic acid (5-HIAA), anandamide (arachidonoylethanolamide [AEA]), and N-palmitoylethanolamide (PEA). A daily questionnaire was used to monitor confounding factors, including pain and stress levels, sleep patterns, and substance use. RESULTS: Increases from baseline in betaE and PEA levels and a decrease in AEA levels occurred immediately posttreatment. At 24 hours posttreatment, similar biomarker changes from baseline were observed. A decrease in stress occurred from baseline to day 5. The change in PEA from baseline to 24 hours posttreatment correlated with the corresponding changes in stress. Subgroup analysis showed that subjects with chronic LBP had significantly reduced 5-HIAA levels at 30 minutes posttreatment (P=.05) and 5-HT levels at 24 hours posttreatment (P=.02) when compared with baseline concentrations. The increase in PEA in subjects with chronic LBP at 30 minutes posttreatment was two times greater than the increase in control subjects. CONCLUSION: Concentrations of several circulatory pain biomarkers were altered after OMT. The degree and duration of these changes were greater in subjects with chronic LBP than in control subjects without the disorder.     

Long-term reduction in pain and disability after surgery with the interspinous device for intervertebral assisted motion (DIAM) spinal stabilization system in patients with low back pain: 4-year follow-up from a longitudinal prospective case series

Patients with low back pain (LBP) suffer chronic disability. In 40% of LBP patients degenerative disc disease (DDD) seems to be the cause. This prospective case series assessed the efficacy of the interspinous device for intervertebral assisted motion (DIAM™) in patients with LBP resulting from DDD. All patients were initially assessed by physical examinations, magnetic resonance imaging, dynamic X-rays and provocative discography. Eligible patients (n = 52) had LBP for a minimum of 4 months, and received surgery with the DIAM™ system 2–4 weeks after diagnosis. Patients were evaluated pre-/post-operatively for pain severity using a visual analogue scale (VAS), and for dysfunction and disability with the Roland–Morris Disability Questionnaire (RMDQ). VAS and RMDQ score changes were assessed using the appropriate contrasts and Bonferroni-corrected P values. As a result, significant (P < 0.0001) pain score reductions were observed between baseline values, and 2 (3.7, 95% CI 3.1; 4.2) and 48 (3.1, 95% CI 2.5; 3.6) months follow-up (intent-to-treat population). Disability scores were significantly (P < 0.0001) reduced between baseline and 2 (8.6, 95% CI 7.4; 9.9) and 48 (7.5, 95% CI 6.1; 8.9) months. Disability scores were similar from months 2 to 48. At 48 months, 67.3% of patients reached the minimum clinically important difference (MCID; ≥1.5-unit improvement) in VAS score and 78.9% of patients reached the MCID (≥30% improvement) in RMDQ score. No complications were associated with surgery. In conclusion, patients with LBP treated with the interspinous DIAM™ system showed significant and clinically meaningful improvements in pain and disability for up to 4 years.     

Increased incidence and severity of somatic dysfunction in subjects with chronic low back pain

CONTEXT: Patients with back pain make more than 14 million office visits per year to US physicians. Many of these patients have chronic low back pain (LBP) and are assumed to have more somatic dysfunction than those without chronic LBP. OBJECTIVE: To investigate incidence and severity of somatic dysfunction of four lumbar vertebral segments (L1-L4). METHODS: Sixteen subjects with chronic LBP and 47 subjects without chronic LBP were each evaluated by two blinded examiners using reliable osteopathic palpatory tests. The incidence and severity of somatic dysfunction for each test were then analyzed within and between the study groups. Results: Resistance to anterior springing (P<.001) and tenderness (P=.002) were found at significantly greater incidence in the chronic LBP group than in the non-LBP group, but there were no significant differences between groups for incidence of tissue texture changes or static rotational asymmetry. Significantly greater severity of tissue texture changes (P=.006), static rotational asymmetry (P=.008), resistance to anterior springing (P<.001), and tenderness (P=.001) were observed in the chronic LBP group than in the non-LBP group. CONCLUSION: When compared with non-LBP subjects, chronic LBP subjects had overall greater severity for each of the four elements of somatic dysfunction evaluated, as well as greater incidence of resistance to anterior springing and tenderness. Somatic dysfunction is more severe in individuals with chronic LBP than in individuals without chronic LBP.     

The impact of custom semirigid foot orthotics on pain and disability for individuals with plantar fasciitis

STUDY DESIGN: Single-group, pre-, and postintervention repeated measures design. OBJECTIVE: To determine the impact of custom semirigid foot orthotics on pain and disability for individuals with plantar fasciitis. BACKGROUND: Few studies have examined the efficacy of foot orthotics for plantar fasciitis, and no single study has yet examined the effects of semirigid foot orthotics on an established quality-of-life instrument. METHODS AND MEASURES: Eight men and 7 women (mean ages 44.7 +/- 9.0 years) who reported having plantar fasciitis symptoms for an average of 21.3 +/- 23.7 months participated in the study. Subjects were timed for a 100-m walk at a self-selected speed, then they rated the pain they experienced during the walk using a 10-cm visual analog scale. Subjects also completed the pain and disability subsections of the Foot Function Index questionnaire. All measures were acquired before the fabrication of custom semirigid foot orthotics and 12 to 17 days following onset of foot orthotic use. RESULTS: Postorthotic 100-m walk times were not significantly different (t = 0.39, P = 0.70) than preorthotic values. Postorthotic pain ratings (mean = 0.7 +/- 0.7) for the 100-m walk were significantly less than (Wilcoxon t = 1, P < 0.005) preorthotic pain ratings (mean = 3.0 +/- 1.7). Postorthotic Foot Function Index pain subsection ratings (Wilcoxon t = 0, P < 0.005) were significantly less than preorthotic ratings, demonstrating a 66% reduction in pain ratings. Postorthotic Foot Function Index disability subsection ratings (Wilcoxon t = 0, P < 0.005) were significantly less than preorthotic ratings, demonstrating a 75% reduction in disability ratings. CONCLUSION: Custom semirigid foot orthotics may significantly reduce pain experienced during walking and may reduce more global measures of pain and disability for patients with chronic plantar fasciitis.     

An alternate method of radiofrequency neurotomy of the sacroiliac joint: a pilot study of the effect on pain, function, and satisfaction

BACKGROUND AND OBJECTIVES: The sacroiliac joint (SIJ) can be a source of chronic refractory mechanical spine pain. Few previous studies have described radiofrequency (RF) sensory denervation of the SIJ; results have been inconsistent and technically demanding. This uncontrolled, prospective, cohort study evaluates the effects of an innovative method of RF ablation of the posterior sensory nerves of the SIJ on pain, analgesic use, disability, and satisfaction of patients suffering with chronic mechanical SIJ pain. METHODS: Nine subjects with SIJ pain, confirmed by a local anesthetic joint block, were studied. Subjects were treated with a series of RF strip lesions performed adjacent to the lateral dorsal foraminal aperture plus conventional monopolar lesioning at the L5 dorsal ramus. Each subject completed a questionnaire twice before and at 1, 3, 6, 9, and 12 months after the procedure. The questionnaire evaluated pain intensity and frequency, analgesic intake, disability, satisfaction (with current pain level and the RF procedure), and procedure complications. Data were analyzed by using linear mixed model analysis. RESULTS: After the procedure, significant reductions of back and leg pain frequency and severity, analgesic intake, and dissatisfaction with their current level of pain occurred. Complications were minimal. Overall, 8 of 9 subjects were satisfied with the procedure. CONCLUSIONS: RF sensory ablation of the SIJ using bipolar strip lesions is a technically uncomplicated and low-risk procedure. The resulting effects on pain, disability, and satisfaction are promising. Further evaluation of this technique, including randomized controlled trials, is recommended.     

The prognosis of chronic low back pain is determined by changes in pain and disability in the initial period

Background context

The recovery of patients with chronic low back pain (LBP) is slow. Furthermore, it is recently proposed that chronic LBP needs a prognostic approach to determine who will develop clinically significant back pain. Therefore, it is imperative to identify prognostic factors that are mostly seen in chronic LBP patients at an early stage. This may give clinicians tailored advice to prevent chronicity or may refer to a specific intervention.

Purpose

To investigate the contribution of demographic, work, clinical, and psychosocial variables, including new prognostic variables as changes in pain intensity and disability status, on the development of chronic LBP.

Study design/setting

Prospective cohort data by merging data from three randomized trials (secondary analyses).

Patient sample

Workers (n=628) on sick leave because of subacute nonspecific LBP.

Outcome measures

Chronic LBP for longer than 6 months (functional measure).

Methods

Potential prognostic variables were demographic, work, clinical, and psychosocial characteristics (self-report measures). We also included as prognostic variables a clinically relevant change in pain intensity and disability status. For the selection of variables and prognostic models, bootstrapping techniques were used in combination with multivariable logistic regression. The explained variance and discrimination were used to evaluate the clinical performance of the models.

Results

The variables most strongly related to chronic LBP were as follows: no clinically relevant change in pain intensity and in disability status in the first 3 months, a higher pain intensity score at baseline, and a higher score for kinesiophobia. This prognostic model had a bootstrap-corrected explained variance of 37% and a discriminative ability (c index) of 0.80.

Conclusions

Clinical-, work-, and psychosocial-related variables contribute to the development of chronic LBP. The most promising variables are a clinically relevant decrease in pain intensity and in disability status in the first 3 months. These variables are relevant for clinicians to advise their patients with respect to preventive measures or treatment strategies.     

Prevalence of low back pain and factors associated with chronic disabling back pain in Japan

Purpose

This study aimed to report lifetime and 4-week low back pain (LBP) prevalence and examine factors associated with chronic LBP and back pain disability over a lifetime in a Japanese adult population.

Methods

In February 2011, 1,063,083 adults aged 20–79 years registered as internet research volunteers were randomly selected to participate in a questionnaire survey. The data from 65,496 respondents were analyzed to calculate age-standardized lifetime and 4-week prevalence. Chronic LBP and back pain disability were defined as LBP lasting for ≥3 months and a consecutive ≥4-day-long absence, respectively. Factors associated with chronic disabling back pain over a lifetime were examined by multiple logistic regression modeling.

Results

The lifetime LBP prevalence was 83 % and 4-week prevalence was 36 %; majority of the respondents had disability-free LBP. Smoking [adjusted odds ratio (aOR): 1.17; 95 % CI: 1.05, 1.30], lower educational level (aOR: 1.21; 95 % CI: 1.09, 1.34), history of disabling back pain among family members and/or significant others (aOR: 1.46; 95 % CI: 1.27, 1.67), occupational LBP (aOR: 1.34; 95 % CI: 1.16, 1.55), traffic injury (aOR: 2.81; 95 % CI: 2.07, 3.81), compensated work injury (aOR: 2.42; 95 % CI: 1.92, 3.05), radiating pain (aOR: 4.94; 95 % CI: 4.45, 5.48), low back surgery (aOR: 10.69; 95 % CI: 9.02, 12.68), and advice to rest upon back pain consultation (aOR: 3.84; 95 % CI: 3.36, 4.40) were associated with chronic disabling back pain over a lifetime.

Conclusions

LBP is common in Japan as in other industrialized countries. The association between the advice to rest and chronic disabling back pain supports recent treatment guidelines emphasizing continuation of daily activities.     

Investigation of elevated fear-avoidance beliefs for patients with low back pain: a secondary analysis involving patients enrolled in physical therapy clinical trials

STUDY DESIGN: Secondary analysis. OBJECTIVE: To investigate the Fear-Avoidance Beliefs Questionnaire (FABQ) for its ability to predict 6-month outcomes for patients with low back pain (LBP) participating in physical therapy clinical trials. BACKGROUND: Consistent evidence suggests that fear-avoidance beliefs are predictive of short-term outcomes for patients with LBP. However, proposed cut-off scores have not been widely investigated for longer-term outcomes in samples of patients receiving physical therapy. METHODS AND MEASURES: Subjects (n = 160) were participants in 2 separate randomized trials that used standard methodology and investigated the efficacy of physical therapy interventions for LBP. Subjects completed baseline measures of pain, disability, fear-avoidance beliefs, and physical impairment. They completed 4 weeks of randomly assigned physical therapy and were reassessed at 6 months with standard examination techniques. The accuracy of previously proposed cut-offs for elevated FABQ scores were determined by independent t tests and chi-square analysis on raw 6-month Oswestry Disability Questionnaire (ODQ) scores, 6-month ODQ change scores, and minimally clinical important difference (MCID) in ODQ scores (6 points). Next, a hierarchical regression model determined which FABQ scale better predicted 6-month ODQ scores after controlling for previously reported prognostic factors and relevant treatment parameters. Last, receiver operating characteristic curve analyses were planned to generate a range of FABQ cut-off scores that predicted 6-month MCID in the ODQ. RESULTS: The previously reported cut-off score for the FABQ physical activity scale (>14) resulted in 111 (69.4%) of 160 patients being classified as having elevated baseline scores, while the previously reported cut-off score for the FABQ work scale (>29) resulted in 19 (11.9%) of 160 patients being classified as having elevated baseline scores. Patients with elevated FABQ physical activity scale scores (>14) had no significant differences in 6-month ODQ outcomes. Patients with elevated FABQ work scale (>29) scores reported higher 6-month ODQ scores and were more likely to have reported no improvement in ODQ score. The final regression model explained 24.4% of the variance in 6-month ODQ scores, with only manipulation and exercise and the FABQ work scale as unique predictors. Fifteen of the subjects (12.7%) had a 6-month change in ODQ that indicated no improvement. The area under the receiver operating characteristic curve for the FABQ physical activity scale predicting this outcome was 0.562 (95% CI: 0.415-0.710) and for the FABQ work scale was 0.694 (95% CI: 0.542-0.846). Cut-off scores were explored for the FABQ work scale only, with positive likelihood ratios that ranged from 1.19 to 5.15 and negative likelihood ratios that ranged from 0.30 to 0.83. CONCLUSIONS: The FABQ work scale was the better predictor of self-report of disability in this sample of patients participating in physical therapy clinical trials. Future studies are necessary to further test and refine the FABQ work scale as a screening tool alone, and in combination with other examination findings.     

EMG analysis of lumbar paraspinal muscles as a predictor of the risk of low-back pain

Studies of EMG power spectra have established associations between low-back pain (LBP) and median frequency (MF). This 2-year prospective study investigates the association of LBP with EMG variables over time. 120 health care workers underwent paraspinal EMG measurements and assessment of back pain disability. The EMG recordings were performed under isometric trunk extension at 2/3 maximum voluntary contraction and acquired from erector spinae muscles at the level of L4/L5. 108 (90%) subjects were reviewed at a minimum 2-year follow up. 16 out of 93 subjects with no history of chronic low-back pain became worse as measured by time off work, disability, reported pain and self-assessment rating. The value of the EMG variable half-width at inception demonstrated significant association with changes in subject’s outcome measure and their own assessment of their LBP at follow up (p < 0.05). Based on self-assessment data, subjects with no history of chronic LBP with half-width of greater than 56 Hz were at threefold greater risk of developing back pain compared with the remainder of the population (p = 0.045). The value of the initial median frequency (IMF) and MF slope at inception were also associated with the subjects’ own assessment of LBP at follow up. Subjects with an IMF greater than 49 Hz were at 5.8-fold greater risk of developing back pain compared with the remainder of the population (p = 0.014). EMG variables recorded from lumbar paraspinal muscles can identify a sub group of subjects at increased risk of developing low-back pain in the future.     

The association between compensation and chronic disabling back pain

BackgroundLow back pain (LBP) is a common and major health problem. Although it is known that psychosocial factors are important predictors of LBP outcome, some factors, including financial compensation, have not been fully studied in Japan. This cross-sectional study aimed to examine the association between LBP compensation (workers’ compensation and automobile insurance claims) and lifetime experience of chronic LBP and back pain disability (chronic disabling LBP) in a Japanese adult population.MethodsIn February 2011, 1,063,083 adults aged 20–79 years registered as Internet research volunteers were invited to complete an online questionnaire. We analyzed the data from 52,650 respondents who had ever experienced LBP. Multiple logistic regression analysis was used to examine the association between LBP compensation and lifetime experience of chronic disabling LBP, adjusting for age, sex, smoking habits, educational level, cause of LBP, history of radiating pain below the knee, and history of low back surgery.ResultsAmong the respondents, 2,039 (3.9 %) had experienced chronic disabling LBP. The prevalence of a history of receiving workers’ compensation or automobile insurance claims was 1.1 % for each. In multiple logistic regression, the odds of chronic disabling LBP were significantly higher among those who received LBP-related compensation (workers’ compensation or automobile insurance claims) compared with respondents who did not receive compensation.ConclusionsThe prevalence of compensated LBP was low. However, a history of compensated LBP was significantly associated with experiencing chronic disabling LBP.     

Responsiveness and minimal clinically important difference for pain and disability instruments in low back pain patients

Background  

The choice of an evaluative instrument has been hampered by the lack of head-to-head comparisons of responsiveness and the minimal clinically important difference (MCID) in subpopulations of low back pain (LBP). The objective of this study was to concurrently compare responsiveness and MCID for commonly used pain scales and functional instruments in four subpopulations of LBP patients.     

Efficacy of low power laser therapy and exercise on pain and functions in chronic low back pain

BACKGROUND AND OBJECTIVES: The aim of this study was to determine whether low power laser therapy (Gallium-Arsenide) is useful or not for the therapy of chronic low back pain (LBP). STUDY DESIGN/MATERIALS AND METHODS: This study included 75 patients (laser + exercise-25, laser alone-25, and exercise alone-25) with LBP. Visual analogue scale (VAS), Schober test, flexion and lateral flexion measures, Roland Disability Questionnaire (RDQ) and Modified Oswestry Disability Questionnaire (MODQ) were used in the clinical and functional evaluations pre and post therapeutically. A physician, who was not aware of the therapy undertaken, evaluated the patients. RESULTS: Significant improvements were noted in all groups with respect to all outcome parameters, except lateral flexion (P < 0.05). CONCLUSIONS: Low power laser therapy seemed to be an effective method in reducing pain and functional disability in the therapy of chronic LBP.     

Repositioning accuracy and movement parameters in low back pain subjects and healthy control subjects

Study Design: A control group study with repeated measures. Objective: To compare trunk repositioning parameters in chronic low back pain (LBP) and healthy subjects. Summary and background data: Recent evidence suggests that chronic LBP patients exhibit deficits in trunk proprioception and motor control. Trunk repositioning and the various spatio-temporal parameters related to it can be used to evaluate sensori-motor control and movement strategies. Methods: Fifteen control subjects and 16 chronic LBP subjects participated in this study. Subjects were required to reproduce different trunk position in flexion (15°, 30° and 60°) and extension (15°). In the learning phase preceding each condition, visual feedback was provided. Following these learning trials, subjects were asked to perform ten consecutive trials without any feedback. Movement time, movement time variability and peak velocity were obtained and a temporal symmetry ratio was calculated. Peak angular position variability and absolute error in peak angular position were also calculated to evaluate spatial accuracy. Results: Two subgroups of LBP patients were identified. One subgroup of LBP subjects demonstrated longer movement time and smaller peak velocities and symmetry ratios than normal subjects. No group difference was observed for peak angular position variability and absolute error in peak angular position. Conclusion: Chronic LBP patients, when given a sufficient learning period, were able to reproduce trunk position with a spatial accuracy similar to control subjects. Some LBP subjects, however, showed modifications of movement time, peak velocity and acceleration parameters. We propose that the presence of persistent chronic pain could induce an alteration or an adaptation in the motor responses of chronic LBP subjects.     

The centralization phenomenon and fear-avoidance beliefs as prognostic factors for acute low back pain: a preliminary investigation involving patients classified for specific exercise

STUDY DESIGN: Secondary analysis of a prospective cohort of patients with acute low back pain (LBP). OBJECTIVES: To determine if the centralization phenomenon and fear-avoidance beliefs predict measurement of pain and disability 6 months after entering the study. BACKGROUND: The centralization phenomenon and fear-avoidance are predictive of future pain and disability. However, previous prognostic studies have not routinely included both measures in homogenous subgroups of patients with acute LBP. METHODS AND MEASURES: Patients completed self-report questionnaires and were evaluated and treated with treatment-based classification guidelines. Only the patients classified for specific exercise were included in this analysis (n = 28). Measures of disability and pain intensity were reassessed at 6 months by mail. Separate hierarchical regression models predicted measures of disability and pain intensity with the centralization phenomenon, fear-avoidance beliefs, and prespecified covariates. RESULTS: There were no significant differences in duration of symptoms, fear-avoidance beliefs, and history of LBP based on the centralization phenomenon (P > .05). Patients reporting the centralization phenomenon were significantly more likely to have leg pain (P < .01). A regression model including initial disability, the centralization phenomenon, and fear-avoidance beliefs about work significantly predicted 6-month disability, explaining 49% of the total variance (P < .001). A regression model that included initial pain intensity and the centralization phenomenon significantly predicted 6-month pain intensity, explaining 29% of the total variance (P < .016). These factors also appeared to be clinically meaningful predictors of outcome, but lacked precision for immediate use in clinical settings. The following covariates were not included in the final regression models: presence of leg pain, history of LBP, and duration of LBP. CONCLUSIONS: Baseline elevation in fear-avoidance beliefs about work and lack of centralization phenomenon predicted higher disability. Baseline lack of centralization phenomenon predicted higher pain intensity. These results can only be generalized to patients with acute LBP classified for specific exercise. It will be necessary to independently validate these prediction models before they can be implemented in clinical settings.