Clinical Trials

Practice-based randomized controlled-comparison clinical trial of chiropractic adjustments and brief massage treatment at sites of subluxation in subjects with essential hypertension: pilot study

Plaugher G, Long CR, Alcantara J, Silveus AD, Wood H, Lotun K, Menke JM, Meeker WC, Rowe SH. J Manipulative Physiol Ther 06/2002; 25(4):221-39
Abstract: To determine the feasibility of conducting a randomized clinical trial in the private practice setting examining short- and long-term effects of chiropractic adjustments for subjects with essential hypertension compared with a brief soft tissue massage, as well as a nontreatment control group. Randomized controlled-comparison trial with 3 parallel groups. Private practice outpatient chiropractic clinic. Twenty-three subjects, aged 24 to 50 years with systolic or diastolic essential hypertension. Two months of full-spine chiropractic care (ie, Gonstead) consisting primarily of specific-contact, short-lever-arm adjustments delivered at motion segments exhibiting signs of subluxation. The massage group had a brief effleurage procedure delivered at localized regions of the spine believed to be exhibiting signs of subluxation. The nontreatment control group rested alone for a period of approximately 5 minutes in an adjustment room. Cost per enrolled subject, as well as systolic and diastolic blood pressure (BP) measured with a random-0 sphygmomanometer and patient reported health status (SF-36). Pilot study outcome measures also included an assessment of cooperation of subjects to randomization procedures and drop-out rates, recruitment effectiveness, analysis of temporal stability of BPs at the beginning of care, and the effects of inclusion/exclusion criteria on the subject pool. Thirty subjects enrolled, yielding a cost of $161 per enrolled subject. One subject was later determined to be ineligible, and 6 others dropped out. In both the chiropractic and massage therapy groups, all subjects were classified as either overweight or obese; in the control group there were only 2 classified as such. SF-36 profiles for the groups were similar to that of a normal population. The mean change in diastolic BP was -4 (95% confidence interval [CI]: -8.6, 0.5) in the chiropractic care group, 0.5 (95% CI: -3.5, 4.5) in the brief massage treatment group, and -4.9 (95% CI: -9.7, -0.1) in the no treatment control group. At the end of the study period, this change was -6.3 (95% CI: 13.1, 0.4), -1.0 (95% CI: -7.5, 15.6), -7.2 (95% CI: -13.3, -1.1) in the 3 study groups. The mean improvements in the chiropractic care and no treatment control groups remained consistent over the follow-up period. This pilot study elucidated several procedural issues that should be addressed before undertaking a full-scale clinical trial on the effects of chiropractic adjustments in patients with essential hypertension. A multidisciplinary approach to recruitment may need to be used in any future efforts because of the limited subject pool of patients who have hypertensive disease but are not taking medications for its control. Measures need to be used to assure comparable groups regarding prognostic variables such as weight. Studies such as these demonstrate the feasibility of conducting a full-scale 3-group randomized clinical trial in the private practice setting.

 Effect of unilateral spinal adjustments on goniometrically-assessed cervical lateral-flexion end-range asymmetries in otherwise asymptomatic subjects

Nansel D, Cremata E, Carlson J, Szlazak M. J Manipulative Physiol Ther 1989; 12:419-427
Abstract: A triple blinded, multiple-measure, experimental protocol was employed in order to investigate the effectiveness of unilateral cervical adjustments on goniometrically assessed cervical lateral-flexion asymmetries. On pretest, subjects selected for the experiments exhibited mean left-right lateral-flexion differences of approximately 14 degrees. In subjects which either received no intervention, or had been subjected only to preliminary palpatory and set-up procedures but no thrust, asymmetry magnitudes were found to be unchanged on goniometric post-testing done 30-45 minutes later. However, in subjects which received lower cervical adjustments performed on the side of most restricted end-range, there was a dramatic reduction in asymmetry magnitudes. Furthermore, the adjustment procedure used in this investigation appeared to be relatively side-specific, since adjustments, when delivered to the less restricted side, were only marginally effective in ameliorating the asymmetries. Potential clinical relevance as well as the possible structural or physiological mechanisms responsible for the results obtained in the study are discussed.

Time course considerations for the effects on unilateral lower cervical adjustments with respect to the amelioration of cervical lateral flexion passive end-range asymmetry

Nansel D, Peneff A, Cremata E, Carlson J.  J Manipulative Physiol Ther 1990; 13:297-304
Abstract: The initial effectiveness as well as the temporal stability of the effect of cervical spinal manipulation with respect to the amelioration of goniometrically verified cervical lateral-flexion passive end-range asymmetry was examined. Responses of two groups of pain-free subjects were compared: a) those exhibiting end-range asymmetries of greater than 10 degrees who, in addition, had suffered previous neck trauma, and: b) those who happened to exhibit end-range asymmetries of greater than 10 degrees but who had no history of prior neck trauma. All subjects received a single lower cervical adjustment delivered to the side of most-restricted end-range, and goniometric reassessments were performed 30 minutes, 4 hours and 48 hours, following the adjustment. A dramatic amelioration of asymmetry was observed in both groups at 30 minutes and 4 hours post-manipulation. Furthermore, the magnitudes of these short-term effects were similar for the two groups. However, by 24 hours, a difference in the temporal responses of the groups had become readily apparent. By 48 hours, the difference was even more striking; whereas 14 of 16 of the subjects with no previous neck trauma continued to exhibit asymmetries of less than 10 degrees (mean +/- SEM = 3.8 +/- 1.0 degree), 12 of the 16 subjects with previous neck trauma had regained asymmetries of greater than 10 degrees (mean +/- SEM = 11.4 +/- 1.7 degrees). These results indicate that among asymptomatic (pain-free) individuals, the mere presence of passive end-range asymmetry as well as the magnitude of the short-term ameliorative effect of cervical manipulation do not distinguish these two categories of subjects. On the other hand, over long periods of time following manipulation, there appears to be a tendency of individuals who have suffered previous neck trauma to re-establish their aberrant cervical motion characteristics. The possible clinical relevance of these findings is discussed, and suggestions put forth regarding the definition of chronic cervical motion dysfunction. Possible mechanisms (e.g. spinal learning) which may be responsible for this condition are also addressed.

Effects of cervical adjustments on lateral-flexion passive end-range asymmetry and on blood pressure, heart rate and plasma catecholamine levels

Nansel D, Jansen R, Cremata E, Dhami MSI, Holley D.  J Manipulative Physiol Ther 1991; 14:450-456
Abstract: The biomechanical and physiological effects of a single, unilateral lower cervical spinal adjustment delivered to the most restricted side of cervical lateral-flexion passive end-range were examined. Only healthy, asymptomatic male subjects who exhibited goniometrically verified lateral-flexion passive range of motion asymmetries of 10 degrees or greater on the morning of the experiment were chosen for the study. Post-treatment goniometric measurements revealed that in sham-adjusted controls, mean lateral-flexion asymmetries had not changed significantly during the 4 hour time period examined. However, in subjects who received lower cervical adjustments, dramatic ameliorations of asymmetry magnitude were observed which persisted throughout the entire 4 hour post-treatment time period. On the other hand, in the face of this rather robust biomechanical effect, heart rate and blood pressure measurements obtained at -60 and -15 minutes prior to treatments, and at 5, 30, 60, 120 and 240 minutes following treatments, revealed no significant differences between adjusted and sham-adjusted subjects at any of the time periods examined. Consistent with this, analysis of the plasma concentrations of norepinephrine, epinephrine and dopamine in serial blood samples collected at these times also failed to reveal significant differences between treatment groups at any of the time periods examined. The results of this investigation indicate that lower cervical adjustments are capable, at least in asymptomatic subjects, of inducing relatively robust biomechanical effects related to passive cervical end-range capability without simultaneously inducing significant alterations in the overall activity of the sympathetic nervous system.

Effectiveness of upper versus lower cervical adjustments with respect to the amelioration of passive rotational versus lateral-flexion end-range asymmetries in otherwise asymptomatic subjects

Nansel D, Peneff A, Quitoriano J. J Manipulative Physiol Ther 1992; 15:99-105
Abstract: The effects of cervical spinal adjustments delivered bilaterally either to the upper cervical region (C2-C3) or to the lower cervical region (C6-C7), were compared in groups of asymptomatic subjects exhibiting goniometrically verified left-right rotational or left-right lateral-flexion passive end-range asymmetries of greater than 10 degrees. Goniometric evaluation both prior to, and again within 30 minutes following treatments revealed that lower cervical adjustments were far more effective for the amelioration of lateral-flexion asymmetries than were upper cervical ones, whereas upper cervical adjustments were found to be more effective for the amelioration of rotational asymmetries than those delivered to the lower cervical region. These results are consistent with the view that passive movement restriction exhibited along the rotational axis is attributable to factors related primarily to the upper cervical region, whereas restrictions of passive movement along the lateral axis are more attributable to factors related to the lower cervical region. Further support for the regional independence of these axis-specific relationships is provided by similar results obtained in groups of subjects who happened to exhibit both rotational, as well as lateral-flexion, asymmetries of greater than 10 degrees on the day of the experiment.

 Likelihood-evidential support and Bayesian re-analysis on a prospective cohort of children and adolescents with mild scoliosis and chiropractic management

Menke JM, Plaugher G, Carrari CA, Coleman RR, Vannetiello, L, Bachman TR. J Ariz Nev Acad Sci 2007; 39:99-111
Abstract: previous study using frequentist analytic methods on a single cohort showed no difference in forty-one patients under chiropractic management for mild or early stage scoliosis. The grantor requested a re-analysis. Plain film radiographs of 41 children and adolescents were re-measured by Risser-Ferguson and Cobb methods. Three magnitudes and three types of change were constructed to cover various notions of scoliosis change: magnitudes of 1°, 3°, or 5°, and types that alternatively included or omitted no change as a possible successful outcome (arrested progression). Improvement was assessed from using three filters across three definitions of progression: 1) curve improved or stable, 2) improved only, and 3) those that either improved or progressed. Data were then analyzed by evidential support methods and Bayesian analyses at each filter and type of progression to establish whether improvement was likely attributable to treatment or spine characteristics. Intra-class correlation for intra-examiner stability was 0.73 by Cobb method. Reliability between the new and the previous examiner was 0.59 for pre- and 0.69 for post-treatment Cobb angles. Reliability increased dramatically when end vertebrae were specified. Ratio of number improved to those progressed to was at least 2:1 for all three levels of filter: 1˚, 3˚, and 5˚. Number of treatments or duration of care were not associated with improvement. However, the number of vertebral segments below the scoliosis curve apex - a measure of curve compression - and bone age accounted for 49% of adjusted R2 in Cobb angle changes. Initial Cobb angle as a clinical predictor was not supported. One treating chiropractor experienced a greater rate of improvement at the highest level of change (5°) in his patients. Results here could not be attributed to management, but could be from a type of scoliosis resolving spontaneously, or a subgroup of scoliosis cases that responded to chiropractic management or manipulation.