Effects of an early multidisciplinary intervention on sickness absence in patients with persistent low back pain-a randomized controlled trial.

BACKGROUND: Multidisciplinary rehabilitation is recommended to reduce sickness absence and disability in patients with subacute or chronic low back pain (LBP). This study aimed to investigate whether a 12-week coordinated work oriented multidisciplinary rehabilitation intervention was effective on return to work and number of days off work during one-year follow-up when compared to usual care. METHODS: This study is a randomized controlled trial comparing the effectiveness of a 12-week multidisciplinary vocational rehabilitation program in addition to usual treatment. 770 patients with LBP, who were sick-listed, or at risk of being sick-listed were included in the study. The primary outcome was number of days off work due to LBP. The secondary outcomes were disability, health-related quality of life, pain, psychological distress and fear avoidance behavior. Data were collected at baseline, at the end of treatment, and at 6- and 12-months follow-up. Analyses were carried out according to the "intention-to-treat" principles. RESULTS: A significant decrease in the number of patients who were on sick-leave was found in both groups at the end of treatment and at 6- and 12-months follow-up. Additionally, disability, pain, health related quality of life, psychological distress, and fear avoidance beliefs improved in both groups. No statistically significant differences were found between the groups on any of the outcomes. CONCLUSIONS: The coordinated multidisciplinary intervention had no additional effect on sickness absence, disability, pain, or health related quality of life as compared with that of usual care. TRIAL REGISTRATION: This study was retrospectively registered in ClinicalTrials.gov (registration ID: NCT01690234). The study was approved by The Danish Regional Ethics Committee (file no: H-C-2008-112) as well as registered at and approved by the Danish Data Protection Agency.

Data Privacy Compliant Validation of Health Insurance Claims Data: the IDOMENEO Approach.

Recently, health insurance claims have regained the attention of the scientific community as a source of real-world evidence in health care research and quality improvement. To date, very few studies are available which investigate the validity of health insurance claims; these may be affected by bias from several sources, such as possible upcoding of co-morbidities and complications for reimbursement advantages. The IDOMENEO study investigates the inpatient treatment of peripheral arterial disease (PAD) comprehensively using various data sources with a consortium involving experts from health care research and data privacy, a large health insurance fund, biostatisticians, jurists, and computer scientists. Prospective registry data were collected from 30-40 vascular centres in Germany using the GermanVasc registry. In addition, health insurance claims data were prospectively collected from BARMER, the second largest health insurance fund in Germany. The consortium is currently developing a data privacy compliant method of health insurance claims data validation, the methodological foundations of which are described here.

No Effect of Acupuncture as Adjunctive Therapy for Patients with Total Knee Replacement: A Randomized Controlled Trial.

Objective: Acupuncture is a low risk option in pain management following total knee replacement as an alternative to opioid analgesics. Therefore, the benefit of acupuncture as adjunct to an exercise program was investigated. Furthermore, the modifying effect of previous benefit from acupuncture was explored. Design: Three weeks postoperatively, eligible patients were randomized to acupuncture and exercises or exercises alone. Setting: An outpatient rehabilitation centre in the municipality of Copenhagen, Denmark. Subjects: A total of 172 patients were included. Methods: Main outcome was proportion of patients that reported a clinically important change in pain at night following each treatment. Secondary outcomes were change in disability measured after termination of the course of treatment and at three months follow-up. Also consumption of medication and walking distance after termination of the course of treatment were assessed. Results: No additional benefit of acupuncture was found on any of the main outcomes. Between-group differences were non-significant in proportions of patients with a clinically important reduction of night pain (Relative Risk: 0.98; 95% Confidence Interval (CI): 0.86-1.11) or evening pain (Relative Risk: 0.94; 95% CI: 0.81-1.0. Conclusions: Our results do not support the addition of acupuncture to routine rehabilitation. Previous benefit from acupuncture was not able to identify those likely to respond to acupuncture. Future studies to investigate whether subgroups of patients would benefit from acupuncture are needed.

Fear avoidance beliefs as a predictor for long-term sick leave, disability and pain in patients with chronic low back pain.

BACKGROUND: Subgrouping patients with chronic low back pain is recommended prior to selecting treatment strategy, and fear avoidance beliefs is a commonly addressed psychological factor used to help this subgrouping. The results of the predictive value of fear avoidance beliefs in patients with chronic low back pain in prognostic studies are, however, not in concordance. Therefore, the objective of this study was to examine the association between fear avoidance beliefs at baseline and unsuccessful outcome on sick leave, disability and pain at 12-month follow-up in patients with entirely chronic low back pain. METHODS: A secondary analysis of data from a randomised controlled trial. Patients with chronic low back pain (n = 559) completed questionnaires at baseline and after 12 months. Multiple logistic regression analyses were conducted to examine the association between fear avoidance beliefs and the outcomes sick leave, disability and pain. RESULTS: Higher fear avoidance beliefs about work at baseline were found to be significantly associated with still being on sick leave (OR 1.11; 95% CI 1.02-1.20) and having no reduction in pain (OR 1.04; 95% CI 1.01-1.08) after 12 months and may be associated with having no reduction in disability (OR 1.03; 95% CI 1.00-1.06) after 12 months (lower limit of 95% CI close to 1.00). Fear avoidance beliefs about physical activity were not found to be associated with the three outcomes. CONCLUSIONS: High fear avoidance beliefs about work are associated with continuous sick leave after 1 year in patients with chronic low back pain. This finding might assist clinicians in choosing targeted treatment strategies in subgroups of working patients with chronic low back pain.

Clinical classification in low back pain: best-evidence diagnostic rules based on systematic reviews.

BACKGROUND: Clinical examination findings are used in primary care to give an initial diagnosis to patients with low back pain and related leg symptoms. The purpose of this study was to develop best evidence Clinical Diagnostic Rules (CDR] for the identification of the most common patho-anatomical disorders in the lumbar spine; i.e. intervertebral discs, sacroiliac joints, facet joints, bone, muscles, nerve roots, muscles, peripheral nerve tissue, and central nervous system sensitization. METHODS: A sensitive electronic search strategy using MEDLINE, EMBASE and CINAHL databases was combined with hand searching and citation tracking to identify eligible studies. Criteria for inclusion were: persons with low back pain with or without related leg symptoms, history or physical examination findings suitable for use in primary care, comparison with acceptable reference standards, and statistical reporting permitting calculation of diagnostic value. Quality assessments were made independently by two reviewers using the Quality Assessment of Diagnostic Accuracy Studies tool. Clinical examination findings that were investigated by at least two studies were included and results that met our predefined threshold of positive likelihood ratio ≥ 2 or negative likelihood ratio ≤ 0.5 were considered for the CDR. RESULTS: Sixty-four studies satisfied our eligible criteria. We were able to construct promising CDRs for symptomatic intervertebral disc, sacroiliac joint, spondylolisthesis, disc herniation with nerve root involvement, and spinal stenosis. Single clinical test appear not to be as useful as clusters of tests that are more closely in line with clinical decision making. CONCLUSIONS: This is the first comprehensive systematic review of diagnostic accuracy studies that evaluate clinical examination findings for their ability to identify the most common patho-anatomical disorders in the lumbar spine. In some diagnostic categories we have sufficient evidence to recommend a CDR. In others, we have only preliminary evidence that needs testing in future studies. Most findings were tested in secondary or tertiary care. Thus, the accuracy of the findings in a primary care setting has yet to be confirmed.

Is the American Society of Shoulder and Elbow Therapists' rehabilitation guideline better than standard care when applied to Bankart-operated patients? A controlled study.

OBJECTIVE: To determine whether there is a difference in shoulder-related physical function and quality of life between postoperative rehabilitation patients receiving standard care and those receiving care according to the American Society of Shoulder and Elbow Therapists' rehabilitation guideline for arthroscopic anterior capsulolabral repair of the shoulder. DESIGN: Descriptive studies with comparison between a retrospective and a prospective cohort. SETTING: Municipal outpatient rehabilitation centre. PATIENTS: A total of 96 arthroscopic Bankart-operated patients. INTERVENTIONS: A total of 52 patients received standard care; 44 patients underwent rehabilitation according to the American Society of Shoulder and Elbow Therapists' rehabilitation guideline. MAIN MEASUREMENTS: Primary outcome variable was Western Ontario Shoulder Instability Index. Secondary outcome measures were Patient-Specific Functional Scale, shoulder range of motion, return to work, return to sports, and costs. RESULTS: There was no significant difference in adjusted mean change scores between the standard care group and the guideline group in the primary outcome variable (Western Ontario Shoulder Instability Index total = 574.85 vs. 644.48) or the secondary outcomes (Patient-Specific Functional Scale = 4.6 vs. 5.0; range of motion in forward flexion = 46.49° vs. 49.58°; external rotation in adduction = 28.58° vs. 34.18°; external rotation in abduction = 51.29° vs. 47.55°; weeks until return to work = 5.2 vs. 6.9; weeks until return to sports =13.9 vs. 13.1; costs = number of visits; 18.5 vs. 15.9). CONCLUSIONS: There were no significant between-group differences in shoulder-related physical function and quality of life between the standard care group and the guideline group, following Bankart operations.

Predicting a clinically important outcome in patients with low back pain following McKenzie therapy or spinal manipulation: a stratified analysis in a randomized controlled trial.

BACKGROUND: Reports vary considerably concerning characteristics of patients who will respond to mobilizing exercises or manipulation. The objective of this prospective cohort study was to identify characteristics of patients with a changeable lumbar condition, i.e. presenting with centralization or peripheralization, that were likely to benefit the most from either the McKenzie method or spinal manipulation. METHODS: 350 patients with chronic low back pain were randomized to either the McKenzie method or manipulation. The possible effect modifiers were age, severity of leg pain, pain-distribution, nerve root involvement, duration of symptoms, and centralization of symptoms. The primary outcome was the number of patients reporting success at two months follow-up. The values of the dichotomized predictors were tested according to the prespecified analysis plan. RESULTS: No predictors were found to produce a statistically significant interaction effect. The McKenzie method was superior to manipulation across all subgroups, thus the probability of success was consistently in favor of this treatment independent of predictor observed. When the two strongest predictors, nerve root involvement and peripheralization, were combined, the chance of success was relative risk 10.5 (95% CI 0.71-155.43) for the McKenzie method and 1.23 (95% CI 1.03-1.46) for manipulation (P = 0.11 for interaction effect). CONCLUSIONS: We did not find any baseline variables which were statistically significant effect modifiers in predicting different response to either McKenzie treatment or spinal manipulation when compared to each other. However, we did identify nerve root involvement and peripheralization to produce differences in response to McKenzie treatment compared to manipulation that appear to be clinically important. These findings need testing in larger studies. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00939107.

Early coordinated multidisciplinary intervention to prevent sickness absence and labour market exclusion in patients with low back pain: study protocol of a randomized controlled trial.

BACKGROUND: Musculoskeletal disorders account for one third of the long-term absenteeism in Denmark and the number of individuals sick listed for more than four weeks is increasing. Compared to other diagnoses, patients with musculoskeletal diseases, including low back pain, are less likely to return to work after a period of sick leave. It seems that a multidisciplinary intervention, including cooperation between the health sector, the social sector and in the work place, has a positive effect on days off work due to musculoskeletal disorders and particularly low back pain. It is a challenge to coordinate this type of intervention, and the implementation of a return-to-work (RTW)-coordinator is suggested as an effective strategy in this process. The purpose of this paper is to describe the study protocol and present a new type of intervention, where the physiotherapist both has the role as RTW-coordinator and treating the patient. METHODS/DESIGN: A randomized controlled trial (RCT) is currently on-going. The RCT includes 770 patients with low back pain of minimum four weeks who are referred to an outpatient back centre. The study population consists of patients, who are sick-listed or at risk of sick-leave due to LBP. The control group is treated with usual care in a team of a physiotherapist, a chiropractor, a rheumatologist and a social worker employed at the centre. The Intervention group is treated with usual care and in addition intervention of a psychologist, an occupational physician, an ergonomist, a case manager from the municipal sickness benefit office, who has the authority in the actual case concerning sickness benefit payment and contact to the patients employer/work place. The treating physiotherapist is the RTW-coordinator. Outcome will be reported at the end of treatment as well as 6 and 12 months follow up. The primary outcome is number of days off work. Secondary outcomes are disability, pain, and quality of life. The study will follow the recommendations in CONSORT-statement in designing and reporting RCTs. DISCUSSION: This large RCT is testing the effectiveness of a preventive intervention targeting patients on short term sick leave or at risk being sick listed because of low back pain. We have developed a novel multidisciplinary team structure using the treating physiotherapist as the return to work coordinator, and having the case manager from the municipal sickness benefit office participating in team meetings. The study has the potential to contribute to the knowledge about how to target the challenges in the treatment of LBP. The aim is to prevent sickness absence and labour market exclusion--both on the individual level and economic costs at community level. Short term results will be available in 2014.This study is approved by the Danish Regional Ethics Committee (J.nr: H-C-2008-112) and is registered at TRIAL REGISTRATION: ClinicalTrials.gov: NCT01690234.

Investigation on the Microstructure of ECAP-Processed Iron-Aluminium Alloys.

The present work deals with adjusting a fine-grained microstructure in iron-rich iron-aluminium alloys using the ECAP-process (Equal Channel Angular Pressing). Due to the limited formability of Fe-Al alloys with increased aluminium content, high forming temperatures and low forming speeds are required. Therefore, tool temperatures above 1100 °C are permanently needed to prevent cooling of the work pieces, which makes the design of the ECAP-process challenging. For the investigation, the Fe-Al work pieces were heated to the respective hot forming temperature in a chamber furnace and then formed in the ECAP tool at a constant punch speed of 5 mm/s. Besides the chemical composition (Fe9Al, Fe28Al and Fe38Al (at.%-Al)), the influences of a subsequent heat treatment and the holding time on the microstructure development were investigated. For this purpose, the average grain size of the microstructure was measured using the AGI (Average Grain Intercept) method and correlated with the aforementioned parameters. The results show that no significant grain refinement could be achieved with the parameters used, which is largely due to the high forming temperature significantly promoting grain growth. The holding times in the examined area do not have any influence on the grain refinement.

Challenges in the Forging of Steel-Aluminum Bearing Bushings.

The current study introduces a method for manufacturing steel-aluminum bearing bushings by compound forging. To study the process, cylindrical bimetal workpieces consisting of steel AISI 4820 (1.7147, 20MnCr5) in the internal diameter and aluminum 6082 (3.2315, AlSi1MgMn) in the external diameter were used. The forming of compounds consisting of dissimilar materials is challenging due to their different thermophysical and mechanical properties. The specific heating concept discussed in this article was developed in order to achieve sufficient formability for both materials simultaneously. By means of tailored heating, the bimetal workpieces were successfully formed to a bearing bushing geometry using two different strategies with different heating durations. A metallurgical bond without any forging defects, e.g., gaps and cracks, was observed in areas of high deformation. The steel-aluminum interface was subsequently examined by optical microscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). It was found that the examined forming process, which utilized steel-aluminum workpieces having no metallurgical bond prior to forming, led to the formation of insular intermetallic phases along the joining zone with a maximum thickness of approximately 5-7 µm. The results of the EDS analysis indicated a prevailing FexAly phase in the resulting intermetallic layer.

Patients With Persistent Low Back Pain and Nerve Root Involvement: To Operate, or Not to Operate, That Is the Question.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: The aims of this study were to evaluate the outcome of surgical and nonsurgical treatment for patients with lumbar herniated disc (LHD) or lumbar spinal stenosis (LSS) after 2 years and to identify predictors for nonsuccess. SUMMARY OF BACKGROUND DATA: Studies regarding the clinician's ability to identify patients with a poor prognosis are not in concurrence and further studies are warranted. METHODS: This study included 390 patients with LHD or LSS referred for surgical evaluation after unsuccessful conservative treatment. Nonsuccess was defined as a Roland-Morris Disability score above 4 (0-23) or a Numeric Rating Scale back and leg pain score above 20 (0-60). Uni- and multivariate logistic regression analyses were used to investigate potential predictive factors including sociodemographic characteristics, history findings, levels of pain and disability, and magnetic resonance imaging findings. RESULTS: Rates of nonsuccess at 2 years were approximately 30% in surgically treated patients with LHD, approximately about 60% in patients with LSS for disability, and 30% and 40%, respectively for pain. For the main outcome variable, disability, in the final multiple logistic regression model, nonsuccess after surgery was associated with male sex (odds ratio [OR] 2.04, 95% confidence interval [CI]: 1.02-4.11, P = 0.04), low level of education (OR 2.60, 95% CI: 1.28-5.29, P = 0.01), high pain intensity (OR 3.06, 95% CI: 1.51-6.21, P < 0.01), and widespread pain (OR 3.59, 95% CI: 1.36-9.46, P = 0.01). CONCLUSION: The results indicate that the prognosis for patients referred for surgery with persistent LHD or LSS and unsuccessful conservative treatment is substantially better when surgery is performed as opposed to not performed. The predictive value of the variables male sex, low level of education, high pain intensity, and widespread pain location found in our study are partly in accordance with results of previous studies. Thus, our results warrant further investigation until firm conclusions can be made. LEVEL OF EVIDENCE: 3.

Mechanical and Thermal Influences on Microstructural and Mechanical Properties during Process-Integrated Thermomechanically Controlled Forging of Tempering Steel AISI 4140.

Thermomechanical treatment (TMT) describes the effect of thermal and mechanical conditions on the microstructure of materials during processing and offers possible integration in the forging process. TMT materials exhibit a fine-grained microstructure, leading to excellent mechanical properties. In this study, a two-step TMT upsetting process with intermediate cooling is used to demonstrate possibilities for a process-integrated treatment and corresponding properties. A water-air-based cooling system was designed to adjust different phase configurations by varying the target temperature and cooling rate. Four different thermal processing routes and four combinations of applied plastic strains are investigated in standardized mechanical tests and metallographic analyses. The applied TMT results in a finely structured bainitic microstructure of the investigated tempering steel AISI 4140 (42CrMo4) with different characteristics depending on the forming conditions. It can be shown that the demands of the standard (DIN EN ISO 683) in a quenched and tempered state can be fulfilled by means of appropriate forming conditions. The yield strength can be enhanced up to 1174 MPa while elongation at break is about 12.6% and absorbed impact energy reaches 58.5 J without additional heat treatment when the material is formed after rapid cooling.

Inter-tester reliability of a new diagnostic classification system for patients with non-specific low back pain.

Most patients referred to physiotherapy with low back pain are without a precise medical diagnosis. Identification of subgroups of non-specific low back pain patients may improve clinical outcomes and research efficiency. A pathoanatomic classification system has been developed, classifying patients with non-specific low back pain into 12 different syndromes and three subcategories based on history and physical examination. The purpose of this study was to estimate the inter-tester reliability of clinical tests used as criteria for classifying patients. Ninety patients with chronic low back pain were each examined by two physiotherapists. A total of four physiotherapists conducted the assessments. Examination findings were recorded independently by the two examiners. Percentage of agreement and kappa coefficients were calculated for each category. The overall rate of agreement was 72% and the kappa coefficient was 0.62 for the mutually exclusive syndromes in the classification system. Agreement rates for each of the syndromes ranged from 74% to 100% and kappa coefficients ranged from 0.44 to 1.00. The findings suggest the inter-tester reliability of the system is acceptable. The relatively modest level of total agreement (39%) for the system as a whole might indicate that the utility of the system for general screening purposes is limited, compared with the utility in identification of particular syndromes. Due to low prevalence of positive findings in some of the syndromes, future work should focus on testing reliability on a larger sample of patients, and testing of validity and feasibility of the system.

The McKenzie method compared with manipulation when used adjunctive to information and advice in low back pain patients presenting with centralization or peripheralization: a randomized controlled trial.

STUDY DESIGN: Randomized controlled trial. OBJECTIVE: To compare the effects of the McKenzie method performed by certified therapists with spinal manipulation performed by chiropractors when used adjunctive to information and advice. SUMMARY OF BACKGROUND DATA: Recent guidelines recommend a structured exercise program tailored to the individual patient as well as manual therapy for the treatment of persistent low back pain. There is presently insufficient evidence to recommend the use of specific decision methods tailoring specific therapies to clinical subgroups of patients in primary care. METHODS: A total of 350 patients suffering from low back pain with a duration of more than 6 weeks who presented with centralization or peripheralization of symptoms with or without signs of nerve root involvement, were enrolled in the trial. Main outcome was number of patients with treatment success defined as a reduction of at least 5 points or an absolute score below 5 points on the Roland Morris Questionnaire. Secondary outcomes were reduction in disability and pain, global perceived effect, general health, mental health, lost work time, and medical care utilization. RESULTS: Both treatment groups showed clinically meaningful improvements in this study. At 2 months follow-up, the McKenzie treatment was superior to manipulation with respect to the number of patients who reported success after treatment (71% and 59%, respectively) (odds ratio 0.58, 95% confidence interval [CI] 0.36 to 0.91, P = 0.018). The number needed to treat with the McKenzie method was 7 (95% CI 4 to 47). The McKenzie group showed improvement in level of disability compared to the manipulation group reaching a statistical significance at 2 and 12 months follow-up (mean difference 1.5, 95% CI 0.2 to 2.8, P = 0.022 and 1.5, 95% CI 0.2 to 2.9, P = 0.030, respectively). There was also a significant difference of 13% in number of patients reporting global perceived effect at end of treatment (P = 0.016). None of the other secondary outcomes showed statistically significant differences. CONCLUSION: In patients with low back pain for more than 6 weeks presenting with centralization or peripheralization of symptoms, we found the McKenzie method to be slightly more effective than manipulation when used adjunctive to information and advice.

Exercise therapy and low back pain: insights and proposals to improve the design, conduct, and reporting of clinical trials.

STUDY DESIGN: A report on plenary presentations and discussions of an expert panel and workshop ("Exercise as a treatment for subacute low back pain") that was held at the Amsterdam Forum VIII on Low Back Pain Research in Primary Care. OBJECTIVE: To highlight important issues regarding the design, conduct, and reporting of exercise trials and to provide suggestions for improvement in each domain. SUMMARY OF BACKGROUND DATA: Despite improvements in the methodologic quality of randomized clinical trials on low back pain (LBP), current trials on exercise therapy still show methodologic flaws in the design and reporting of studies. METHODS: Important issues in the design, conduct, and reporting of exercise trials for LBP were introduced by 4 presenters, and this was followed by a group discussion among 40 attendees. Conclusions and recommendations were extracted by the workshop panelists and summarized in this paper. RESULTS.: Workshop discussion led to the following recommendations: (1) specify a theoretical framework for exercise therapy for designing the intervention and selecting appropriate treatment efficacy measures; (2) to overcome blinding problems in exercise trials, include sham interventions and assess the success of blinding; (3) evaluate the role of patient-provider interactions through the use of self-report or observational measures; (4) to assure quality of treatment, use exercise interventions that reference existing exercise guidelines; (5) use subgroup analyses to identify subgroups of patients most likely to benefit; (6) in reporting exercise trials, include an extensive description of the study population, a detailed exercise protocol, and some measure of patient compliance; (7) further categorization of exercise interventions is needed, in terms of concept, mode, intensity, duration, frequency, and length; and (8) trial;1>registration and publication of detailed study protocols may help to strengthen the evidence-based concerning exercise therapy for LBP. CONCLUSION: By paying proper attention to issues concerning the design and reporting of exercise protocols when conducting future exercise trials, research may provide a stronger evidence basis for recommending or not recommending various exercise therapies for LBP.

One-year follow-up comparison of the effectiveness of McKenzie treatment and strengthening training for patients with chronic low back pain: outcome and prognostic factors.

STUDY DESIGN: A randomized controlled trial with multivariable analyses of prognostic factors. OBJECTIVE: To report the long-term outcome of McKenzie treatment compared with strengthening training. Further, to determine patient-related factors associated with poor outcome 14 months after completion of treatment. SUMMARY OF BACKGROUND DATA: Exercise therapy is widely recommended for patients with chronic low back pain. However, reports vary considerably concerning characteristics of patients who will not respond to treatment. Knowledge of factors associated with poor outcome may assist identification of patients requiring special attention. METHODS: A total of 260 patients with chronic low back pain were included in a previously reported randomized controlled trial of McKenzie therapy versus strengthening training. Outcome variables were: functional status, pain level, work status, and use of healthcare services during follow-up. Also, factors associated with withdrawal during the intervention were sought identified. The following factors of possible prognostic significance were determined: levels of pain and disability, pain-distribution, duration of symptoms, smoking habits, leisure activities, workload, job satisfaction, treatment preference, outcome expectations, treatment modality received, compliance with home exercises during follow-up, and demographic variables such as age, gender, work status, and application for pension. Association between variables was examined by multiple logistic regression analysis and odds ratios. RESULTS: No differences in outcomes were found between the treatment groups at 14 months of follow-up. Low level of pain intensity and disability, sick leave at entry, low pretreatment expectations of future work ability, withdrawal during treatment, and discontinuance of exercises after the end of the treatment period were associated with poor outcome. CONCLUSION: Poor long-term outcome of exercise therapy for chronic low back pain can be explained by a number of patient-related factors. Different prognostic factors were associated with different outcomes. These factors were more important in determining outcome than the exercise-programs studied.

The effect of McKenzie therapy as compared with that of intensive strengthening training for the treatment of patients with subacute or chronic low back pain: A randomized controlled trial.

STUDY DESIGN: A randomized controlled comparative trial with an 8-month follow-up period was conducted. OBJECTIVE: To compare the effect of the McKenzie treatment method with that of intensive dynamic strengthening training in patients with subacute or chronic low back pain. SUMMARY OF BACKGROUND DATA: Randomized studies indicate that the efficacy of the McKenzie method in the treatment of patients with acute or subacute low back pain is debatable. Currently, no randomized studies examining the effects of this method for patients with chronic low back pain have been published. METHODS: For this study, 260 consecutive patients with low back pain and at least 8 weeks duration of symptoms (85% of the patients had more than 3 months duration of symptoms) were randomized into two groups: Group A was treated with the McKenzie method (n = 132), and Group B was treated with intensive dynamic strengthening training (n = 128). The treatment period for both groups was 8 weeks at an outpatient clinic, followed by 2 months of self-training at home. Treatment results were recorded at the end of the treatment period at the clinic, then 2 and 8 months after. In both groups, 30% of the patients were lost to follow-up evaluation. An intention-to-treat analysis of the main effect variables, disability, and pain was performed for all the patients included in the study. A supplementary analysis of the 180 patients who completed the full treatment program also was undertaken. RESULTS: Intention-to-treat analysis showed a tendency toward a difference in reduction of disability in favor of the McKenzie group at the 2-month follow-up assessment (P = 0.04), but no differences at the end of treatment and at the 8-month follow-up evaluation. No differences in reduction of pain were observed at any time between the groups. The supplementary analysis of the patients who had completed the full intervention showed a tendency toward a difference in favor of the McKenzie method in reduction of pain at the end of treatment (P = 0.02). This difference reached statistical significance at the 2-month follow-up assessment (P = 0.01), but no difference was found after 8 months. The supplementary analysis showed no differences between the groups with regard to reduction of disability. CONCLUSION: The McKenzie method and intensive dynamic strengthening training seem to be equally effective in the treatment of patients with subacute or chronic low back pain.