Low back pain risk factors associated with persistence, recurrence and delayed presentation

BACKGROUND: There is little knowledge in the literature on the role of time-related variables for the prognosis of acute and subacute low back pain (LBP). OBJECTIVE: The aim of this study was to estimate the relationship between time-related LBP characteristics and prognostic factors for acute/subacute LBP. METHODS: We performed a prospective inception cohort study of 315 patients attending a health practitioner for acute/subacute LBP or recurrent LBP. One-tailed correlations were conducted between patient characteristics and time-related variables. RESULTS: The pattern of correlation between risk factors for and resources against persistent LBP differed between three time-related variables. 'Subacute LBP' and 'delayed presentation' were positively associated with psychological factors. Both indicators were negatively correlated with resources against development of persistent LBP. Moreover, 'delayed presentation' was related positively with occupational stressors. In contrast, 'recurrent LBP' was only related to more impaired health-related factors. CONCLUSIONS: Patients with current LBP waiting longer until seeking help in primary care have a more disadvantageous profile of occupational and psychological risk factors and lower resource levels. A similar but less pronounced pattern occurred in those with subacute LBP compared to those with acute LBP. Consideration of time characteristics of LBP may help to better understand LBP.

Reliability of Quantitative Sensory Tests in a Low Back Pain Population.

BACKGROUND AND OBJECTIVES Reliability is an essential condition for using quantitative sensory tests (QSTs) in research and clinical practice, but information on reliability in patients with chronic pain is sparse. The aim of this study was to evaluate the reliability of different QST in patients with chronic low back pain. METHODS Eighty-nine patients with chronic low back pain participated in 2 identical experimental sessions, separated by at least 7 days. The following parameters were recorded: pressure pain detection and tolerance thresholds at the toe, electrical pain thresholds to single and repeated stimulation, heat pain detection and tolerance thresholds at the arm and leg, cold pain detection threshold at the arm and leg, and conditioned pain modulation using the cold pressor test.Reliability was analyzed using the coefficient of variation, the coefficient of repeatability, and the intraclass correlation coefficient. It was judged as acceptable or not based primarily on the analysis of the coefficient of repeatability. RESULTS The reliability of most tests was acceptable. Exceptions were cold pain detection thresholds at the leg and arm. CONCLUSIONS Most QST measurements have acceptable reliability in patients with chronic low back pain.

Linking altered central pain processing and genetic polymorphism to drug efficacy in chronic low back pain.

BACKGROUND Inability to predict the therapeutic effect of a drug in individual pain patients prolongs the process of drug and dose finding until satisfactory pharmacotherapy can be achieved. Many chronic pain conditions are associated with hypersensitivity of the nervous system or impaired endogenous pain modulation. Pharmacotherapy often aims at influencing these disturbed nociceptive processes. Its effect might therefore depend on the extent to which they are altered. Quantitative sensory testing (QST) can evaluate various aspects of pain processing and might therefore be able to predict the analgesic efficacy of a given drug. In the present study three drugs commonly used in the pharmacological management of chronic low back pain are investigated. The primary objective is to examine the ability of QST to predict pain reduction. As a secondary objective, the analgesic effects of these drugs and their effect on QST are evaluated. METHODS/DESIGN In this randomized, double blinded, placebo controlled cross-over study, patients with chronic low back pain are randomly assigned to imipramine, oxycodone or clobazam versus active placebo. QST is assessed at baseline, 1 and 2 h after drug administration. Pain intensity, side effects and patients' global impression of change are assessed in intervals of 30 min up to two hours after drug intake. Baseline QST is used as explanatory variable to predict drug effect. The change in QST over time is analyzed to describe the pharmacodynamic effects of each drug on experimental pain modalities. Genetic polymorphisms are analyzed as co-variables. DISCUSSION Pharmacotherapy is a mainstay in chronic pain treatment. Antidepressants, anticonvulsants and opioids are frequently prescribed in a "trial and error" fashion, without knowledge however, which drug suits best which patient. The present study addresses the important need to translate recent advances in pain research to clinical practice. Assessing the predictive value of central hypersensitivity and endogenous pain modulation could allow for the implementation of a mechanism-based treatment strategy in individual patients. TRIAL REGISTRATION Clinicaltrials.gov, NCT01179828.

Outcome of low back pain in general practice: a prospective study

Objectives: To investigate the claim that 90% of episodes of low back pain that present to general practice have resolved within one month.

Joining forces - Combining cognition-targeted motor control training with group or individual pain physiology education: A successful treatment for chronic low back pain

Chronic unremittent low back pain (LBP) is characterised by cognitive barriers to treatment. Combining a motor control training approach with individualised education about pain physiology is effective in this group of patients. This randomized comparative trial (i) evaluates an approach to motor control acquisition and training that considers the complexities of the relationship between pain and motor output, and (ii) compares the efficacy and cost of individualized and group pain physiology education. After an "ongoing usual treatment" period, patients participated in a 4-week motor control and pain physiology education program. Patients received four one-hour individualized education sessions (IE) or one 4-hour group lecture (GE). Both groups reduced pain (numerical rating scale) and disability (Roland Morris Disability Questionnaire). IE showed bigger decreases, which were maintained at 12 months (P < 0.05 for all). The combined motor control and education approach is effective. Although group education imparts a lesser effect, it may be more cost-efficient. [ABSTRACT FROM AUTHOR]

Core stability exercise in chronic low back pain

Exercise is commonly used in the management of chronic musculoskeletal conditions, including chronic low back pain (CLBP). The focus of exercise is varied and may include parameters ranging from strength and endurance training, to specific training of muscle coordination and control. The assumption underpinning these approaches is that improved neuromuscular function will restore or augment the control and support of the spine and pelvis. In a biomechanical model of CLBP, which assumes that pain recurrence is caused by repeated mechanical irritation of pain sensitive structures [1], it is proposed that this improved control and stability would reduce mechanical irritation and lead to pain relief [1]. Although this model provides explanation for the chronicity of LBP, perpetuation of pain is more complex, and contemporary neuroscience holds the view that chronic pain is mediated by a range of changes including both peripheral (eg, peripheral sensitization) and central neuroplastic changes [2]. Although this does not exclude the role of improved control of the lumbar spine and pelvis in management of CLBP, particularly when there is peripheral sensitization, it highlights the need to look beyond outdated simplistic models. One factor that this information highlights is that the refinement of control and coordination may be more important than simple strength and endurance training for the trunk muscles. The objective of this article is to discuss the rationale for core stability exercise in the management of CLBP, to consider critical factors for its implementation, and to review evidence for efficacy of the approach.