Ultrasound analysis of the vertebral artery during non-thrust cervical translatoric spinal manipulation

Objective

Cervical translatoric spinal manipulation (TSM) techniques have been suggested as a safer alternative to cervical thrust rotatory techniques. The objective of this study was to determine the effect of three C5–C6 non-thrust TSM techniques on vertebral artery (VA) lumen diameter (LD) and two blood flow velocity parameters. The two-tailed research hypothesis was that the TSM techniques would result in a significant change (increase or decrease) in blood flow velocity and arterial LD at the C5–C6 intertransverse portion of the VA.

Methods

In a sample of 30 subjects representative of a clinical population, color-coded duplex Doppler diagnostic ultrasound imaging was used to collect data on LD, peak systolic velocity (PSV), and end diastolic velocity with the cervical spine positioned in neutral and in three different manipulation positions. Pair-wise mean differences between measurements at baseline (neutral position) and in all three manipulation positions were analyzed using two-tailed paired t-tests with alpha set at 0·05.

Results

Of the 18 paired comparisons, there were four statistically significant differences between measurements in the neutral position and a manipulation position, three concerning LD and one PSV.

Discussion

The three significant differences in LD ranged from 4·6 to 3·2% and were not associated with changes in blood flow velocity. The one significant change in PSV was only 6·6 cm/s. A value that still greatly exceeded the end diastolic velocity. No subject experienced symptoms associated with VA compromise. This study has provided evidence for the safety of the three lower cervical non-thrust TSM techniques on the current population studied. Further study is required on thrust versus non-thrust TSM techniques and on levels other than C5–C6.     

Substance or space? The relative importance of substance properties and environmental characteristics in modeling the fate of chemicals in Europe

The relative influence of substance properties and of environmental characteristics on the variation in the environmental fate of chemicals was studied systematically and comprehensively. This was done by modeling environmental concentrations for 200 sets of substance properties, representative of organic chemicals used, and 137 sets of environmental characteristics, representative of regions in Europe of 250 x 250 km. Since it was expected that the model scale has an influence on the predicted concentration variations, the calculations were repeated for regions with a 100 x 100 km and 50 x 50 km area. Stepwise multiple regression analysis was performed to determine the contribution of each of the individual input parameters on the total concentration variation. Depending on the scenario, the range in predicted environmental concentrations spreads from two up to nine orders of magnitude. In accord with earlier studies, variation in the fate of chemicals in the environment appeared to depend mainly on substance-specific partition coefficients and degradation rates. For the estimation of soil and water concentrations with direct emissions to these compartments, however, the influence of spatial variation in environmental characteristics can mount up to two orders of magnitude, a range that can be significant to account for in certain model applications. Concentration differences in water and soil are predicted to be larger if a smaller region is applied in the model calculations, and the relative influence of environmental characteristics on the total variation increases on a more detailed spatial scale. It is argued that the influence of environmental characteristics as predictors of exposure concentrations of chemicals deserves better attention in comparative risk assessment with conventional nonspatial multimedia box models.     

Evidence-Based Diagnosis and Treatment of the Painful Sacroiliac Joint

Sacroiliac joint (SIJ) pain refers to the pain arising from the SIJ joint structures. SIJ dysfunction generally refers to aberrant position or movement of SIJ structures that may or may not result in pain. This paper aims to clarify the difference between these clinical concepts and present current available evidence regarding diagnosis and treatment of SIJ disorders. Tests for SIJ dysfunction generally have poor inter-examiner reliability. A reference standard for SIJ dysfunction is not readily available, so validity of the tests for this disorder is unknown. Tests that stress the SIJ in order to provoke familiar pain have acceptable inter-examiner reliability and have clinically useful validity against an acceptable reference standard. It is unknown if provocation tests can reliably identify extra-articular SIJ sources of pain. Three or more positive pain provocation SIJ tests have sensitivity and specificity of 91% and 78%, respectively. Specificity of three or more positive tests increases to 87% in patients whose symptoms cannot be made to move towards the spinal midline, i.e., centralize. In chronic back pain populations, patients who have three or more positive provocation SIJ tests and whose symptoms cannot be made to centralize have a probability of having SIJ pain of 77%, and in pregnant populations with back pain, a probability of 89%. This combination of test findings could be used in research to evaluate the efficacy of specific treatments for SIJ pain. Treatments most likely to be effective are specific lumbopelvic stabilization training and injections of corticosteroid into the intra-articular space.Key Words: Corticosteroid Injection, Diagnostic Accuracy, Intra-Articular Injection, Lumbopelvic Stabilization Training, Pregnancy-Related Pelvic Girdle Pain, Sacroiliac Joint Dysfunction, Sacroiliac Joint PainThe relationship between the sacroiliac joint (SIJ) and low back pain has been a subject of debate with some researchers regarding SIJ pain as a major contributor to the low back pain problem¹ with others regarding it as unimportant or irrelevant². It is now generally accepted that about 13% (95% CI: 9-26%) of patients with persistent low back pain have the origin of pain confirmed as the SIJ³. Movement and positional abnormalities of the SIJ and their treatments have appeared in the manual therapy, manual medicine, osteopathic, and chiropractic literatures from the 19^th century onwards^4–7. The prevalence of these disorders is reported as being about 20% in college students⁸ and between 8 and 16% in asymptomatic individuals⁹. The relationship between perceived motion and positional abnormalities remains unclear^8,10, and it is claimed that every patient with low back pain has these abnormalities, e.g., a perceivable anterior rotary subluxation of the ilium, and that the great majority can be made rapidly pain-free by its manual correction¹¹. The purpose of this commentary is to clarify the conceptual distinction between these perceived anatomical and biomechanical abnormalities, i.e., SIJ dysfunction, and pain arising from the SIJ, and its relation to the common complaint of low back and referred pain into the buttock, pelvis, and lower extremity. In addition, fruitful directions for future research are discussed in some detail.There are two clinical perspectives to consider: the SIJ as a load-transferring mechanical junction between the pelvis and the spine that may cause either the SIJ or other structures to produce painful stimuli, and the SIJ as a source of pain. The first perspective proposes that the joint is malfunctioning in some manner and the word dysfunction is commonly used to encapsulate the complexity of aberrations believed to occur. Unfortunately, the terms SIJ dysfunction and SIJ pain are commonly used interchangeably as though they have the same meaning. In this paper, these two terms will be clearly differentiated.     

Social skills as precursors of cannabis use in young adolescents: a TRAILS study

Social skills (cooperation, assertion, and self-control) were assessed by teachers for a longitudinal cohort of (pre)adolescents, with measurements at average ages 11.1 (baseline) and 16.3 years (follow-up). Prospective associations with participants' self-reported use of cannabis, (age of) onset of cannabis use, and frequency of use at follow-up were examined using multinomial logistic regression analyses. Teacher-reported social skills predicted different aspects of cannabis use independent of better known factors such as presence of externalizing behavior and use of other substances. The direction of associations depended on the type of social skill. Good cooperation skills during early adolescence were associated with a reduced risk of lifetime cannabis use and a reduced risk of using cannabis on a regular basis. On the other hand, assertion at age 11 increased the risk of lifetime cannabis use and of using cannabis on an experimental basis.