Jeanmarie R. Burke

Spinal reflex excitability changes after cervical and lumbar spinal manipulation: a comparative study

BACKGROUND CONTEXT Spinal manipulation (SM) is a commonly employed nonoperative treatment modality in the management of patients with neck, low back or pelvic pain. One basic physiologic response to SM is a transient decrease in motoneuron activity as assessed using the Hoffmann reflex (H-reflex) technique. Previous research from our laboratory indicates that both SM with a high-velocity, low-amplitude thrust and mobilization without thrust produced a profound but transient attenuation of motoneuronal activity of the lumbosacral spine in asymptomatic subjects. To date, effects of cervical SM procedures on the excitability cervical motoneuron pools are unknown. PURPOSE The objective of this research was to a gain a more complete understanding of the physiologic effects of SM procedures on motoneuron activity, by comparing the effects of regional SM on cervical and lumbar motoneuron pool excitability. STUDY DESIGN/SETTING Maximal H-reflex amplitudes were recorded before and after SM in both the cervical and lumbar regions of asymptomatic subjects in two successive experimental sessions. PATIENT SAMPLE Asymptomatic, young healthy volunteers were used in this study. OUTCOME MEASURES Changes in flexor carpi radialis and gastrocnemius H-reflex amplitudes before and after SM procedures. METHODS H-reflexes recorded form the tibial and median nerves were evaluated before and after lumbar and cervical SM, respectively. RESULTS Both Lumbar and cervical SM produced a transient but significant attenuation of motoneuron excitability. The attenuation of the tibial nerve H-reflex amplitude was proportionately greater than that of the median nerve, which occurred after cervical SM. CONCLUSIONS SM procedures lead to transient suppression of motoneuron excitability, as assessed by the H-reflex technique. Lumbar spine SM appears to lead to greater attenuation of motoneuron activity compared with that of the cervical region. Thus, these two distinct regions of the spine may possess different responsiveness levels to spinal manipulative therapy.

Motor-Evoked Potentials Recorded from Lumbar Erector Spinae Muscles: A Study of Corticospinal Excitability Changes Associated with Spinal Manipulation

OBJECTIVE The purpose of this study was to determine if high-velocity, low-amplitude spinal manipulation (SM) altered the effects of corticospinal excitability on motoneuron activity innervating the paraspinal muscles. In a previous study using transcranial magnetic stimulation (TMS), augmentation of motor-evoked potentials (MEPs) from the gastrocnemius muscle after lumbar SM was reported. To date, there is no known report of the effect of SM on paraspinal muscle excitability. METHODS The experimental design was a prospective physiologic evaluation of the effects of SM on corticospinal excitability in asymptomatic subjects. The TMS-induced MEPs were recorded from relaxed lumbar erector spinae muscles of 72 asymptomatic subjects. The MEP amplitudes were evaluated pre-SM and post-SM or conditions involving prethrust positioning and joint loading or control. RESULTS There was a transient increase in MEP amplitudes from the paraspinal muscles as a consequence of lumbar SM (F([6,414]) = 8.49; P < .05) without concomitant changes after prethrust positioning and joint loading or in control subjects (P > .05). These data findings were substantiated by a significant condition x time interaction term (F([12,414]) = 2.28; P < .05). CONCLUSIONS These data suggest that there is a postsynaptic facilitation of alpha motoneurons and/or corticomotoneurons innervating paraspinal muscles as a consequence of SM. It appears that SM may offer unique sensory input to the excitability of the motor system as compared to prethrust positioning and joint loading and control conditions.

A Cross-Sectional Analysis of Clinical Outcomes Following Chiropractic Care in Veterans With and Without Post-Traumatic Stress Disorder

This study was a cross-sectional analysis of clinical outcomes for 130 veteran patients with neck or low back complaints completing a course of care within the chiropractic clinic at the VA of Western New York in 2006. Multivariate analysis of variance (MANOVA) was utilized, comparing baseline and discharge scores for both the neck and low back regions and for those patients with and without post-traumatic stress disorder (PTSD). Patients with PTSD (n = 21) experienced significantly lower levels of score improvement than those without PTSD (n = 119) on self-reported outcome measures of neck and low back disability. These findings, coupled with the theorized relationships between PTSD and chronic pain, suggest that the success of conservative forms of management for veteran patients with musculoskeletal disorders may be limited by the presence of PTSD. Further research is warranted to examine the potential contributions of PTSD on chiropractic clinical outcomes with this unique patient population.

Prospective case series on the effects of lumbosacral manipulation on dysmenorrhea.

OBJECTIVE The objective of this prospective case series was to collect preliminary data as to the effectiveness of a specific chiropractic technique, drop table method, in the treatment of primary dysmenorrhea. METHODS Over a 4-week period, 16 females were screened for symptoms of primary dysmenorrhea and motion restrictions of the lumbosacral spine. Thirteen subjects were enrolled into the study. Bilateral and unilateral lumbosacral flexion and extension restrictions were treated using drop table manipulations 3 times during each of the 2 consecutive menstrual cycles. Before entering the study and at the end of each menstrual cycle, the subjects self-reported ratings of menstrual pain (abdominal, pelvic, and low back pain) and associated symptoms of primary dysmenorrhea using Numeric Pain Scale. Numeric Pain Scale ratings for menstrual pain were the primary outcome measures. RESULTS The median age was 26 years, and the median self-reported duration of the symptoms was 12 years. At baseline, all subjects reported pain severity scores of 5 or higher for at least 2 of 3 anatomical sites: lower or general abdominal pain and/or lower back pain. Using the 95% confidence interval (CI) as an estimate, clinically meaningful changes (<5) in general abdominal pain and lower back pain were evident for most patients during the treatment phase, whereas for lower abdominal pain, the improvements were subject and cycle dependent. CONCLUSIONS Menstrual pain associated with primary dysmenorrhea may be alleviated with treatment of motion segment restrictions of the lumbosacral spine with drop table technique.

Spinal Manipulative Therapy for Elderly Patients With Chronic Obstructive Pulmonary Disease: A Case Series

OBJECTIVE The objective of this case series is to report the results of spinal manipulative therapy (SMT) for people with chronic obstructive pulmonary disease (COPD) who were older than 65 years. METHODS The study design was a prospective case series. Six patients of a long-term care center who were older than 65 years and having COPD underwent a course of 12 SMT sessions over a 4-week period. Each SMT session consisted of manually applied spinal manipulation and instrument-assisted spinal manipulation delivered by a doctor of chiropractic. Lung function measurements were recorded at baseline and at 2 and 4 weeks. The occurrence and type of any adverse events (AEs) related to SMT were recorded at each SMT session. RESULTS One male and 5 female patients took part in the study. The average age was 79.1 years (range, 68-89 years). There was a clinically significant increase in forced expiratory volume in the first second after SMT in 4 of the 6 patients at 2 weeks. This was sustained in only 1 patient at 4 weeks. No clinically significant changes were observed for forced vital capacity at 2 or 4 weeks. One hundred forty-four manually applied spinal manipulations and 72 instrument-assisted spinal manipulations were administered during the intervention period. No major or moderate AEs were reported. Only minor AEs were reported after 29% of the intervention sessions, with 1 AE being reported for each patient. All AEs resolved within 48 hours. CONCLUSIONS This case series offers preliminary evidence that SMT may have the potential to benefit lung function in patients with COPD who are older than 65 years.

The reliability of the Associate Platinum digital foot scanner in measuring previously developed footprint characteristics: a technical note.

OBJECTIVE An ink pad and paper, pressure-sensitive platforms, and photography have previously been used to collect footprint data used in clinical assessment. Digital scanners have been widely used more recently to collect such data. The purpose of this study was to evaluate the intra- and interrater reliability of a flatbed digital image scanning technology to capture footprint data. METHODS This study used a repeated-measures design on 32 (16 male 16 female) healthy subjects. The following measured indices of footprint were recorded from 2-dimensional images of the plantar surface of the foot recorded with an Associate Platinum (Foot Levelers Inc, Roanoke, VA) digital foot scanner: Staheli index, Chippaux-Smirak index, arch angle, and arch index. Intraclass correlation coefficient (ICC) values were calculated to evaluate intrarater, interday, and interclinician reliability. RESULTS The ICC values for intrarater reliability were greater than or equal to .817, indicating an excellent level of reproducibility in assessing the collected images. Analyses of variance revealed that there were no significant differences between raters for each index (P > .05). The ICC values also indicated excellent reliability (.881-.971) between days and clinicians in all but one of the indices of footprint, arch angle (.689), with good reliability between clinicians. The full-factorial analysis of variance model did not reveal any interaction effects (P > .05), which indicated that indices of footprint were not changing across days and clinicians. CONCLUSIONS Scanning technology used in this study demonstrated good intra- and interrater reliability measurements of footprint indices, as demonstrated by high ICC values.

Nutritional counseling in the chiropractic practice: a survey of New York practitioners.

OBJECTIVE The purpose of this pilot study is to determine the quality of nutritional counseling that the chiropractic patient receives, for what conditions, and the need to establish easy-to-use protocols for nutritional counseling. METHODS Chiropractors practicing in the state of New York were surveyed and were asked if they valued the use of nutritional counseling, if they used it, if they charged for it, what are the barriers for not doing more of it, and what types of counseling they put into practice. Information regarding what types of conditions the chiropractors treated with nutritional counseling and the level of interest they had in furthering their education in the field of nutrition was also collected. There was no statistical validation of the survey, but demographics were included to determine if the sample was representative of practicing chiropractors. RESULTS Eighty percent of the respondents used some form of counseling in their practices but desired to have more knowledge in the area of clinical nutrition. Most preferred online courses to obtain this knowledge. Chiropractors treated a variety of chronic disorders, such as obesity, diabetes, coronary artery disease, and conditions affecting the musculoskeletal system. CONCLUSION With 80% of the doctors who participated in the survey reporting they incorporate some form of nutritional counseling into their practices, it is suggested that the chiropractic physician is interested in a holistic practice. The next step is a comprehensive survey to determine the needs of chiropractors in the United States, so standardized protocols can be created that suit the needs of practitioners nationwide.

Effects of the homeopathic remedy arnica on attenuating symptoms of exercise-induced muscle soreness

OBJECTIVE To evaluate the clinical efficacy of Arnica at a high potency (200c), on moderating delayed onset muscle soreness and accompanying symptoms of muscle dysfunction. METHODS Twenty subjects completed a maximal eccentric exercise protocol with the non-dominate elbow flexors to induce delayed onset muscle soreness. Either Arnica or placebo tablets were administered in a random, double- blinded fashion immediately after exercise and at 24 hours and 72 hours after exercise. Before exercise, immediately post-exercise, and at 24, 48, 72, and 96 hours post-exercise, assessments of delayed onset muscle soreness and muscle function included: 1) muscle soreness and functional impairment; 2) maximum voluntary contraction torque; 3) muscle swelling; and 4) range of motion tests to document spontaneous muscle shortening and muscle shortening ability. Blood samples drawn before exercise and at 24, 48, and 96 hours after exercise were used to measure muscle enzymes as indirect indices of muscle damage. RESULTS Regardless of the intervention, the extent of delayed onset muscle soreness and elevations in muscle enzymes were similar on the days following the eccentric exercise protocol. The post-exercise time profiles of decreases in maximum voluntary contraction torque and muscle shortening ability and increases in muscle swelling and spontaneous muscle shortening were similar for each treatment intervention. CONCLUSIONS The results of this study did not substantiate the clinical efficacy of Arnica at a high potency on moderating delayed onset muscle soreness and accompanying symptoms of muscle dysfunction. Despite the findings of this study, future investigations on the clinical efficacy of homeopathic interventions should consider incorporating research strategies that emphasize differential therapeutics for each patient rather than treating a specific disease or symptom complex, such as DOMS, with a single homeopathic remedy.

Understanding inhibitory mechanisms of lumbar spinal manipulation using H-reflex and F-wave responses: A methodological approach

The purpose of this research was to characterize unique neurophysiologic events following a high velocity, low amplitude (HVLA) spinal manipulation (SM) procedure. Descriptive time series analysis techniques of time plots, outlier detection and autocorrelation functions were applied to time series of tibial nerve H-reflexes that were evoked at 10-s intervals from 100 s before the event until 100 s after three distinct events L5-S1 HVLA SM, or a L5-S1 joint pre-loading procedure, or the control condition. Sixty-six subjects were randomly assigned to three procedures, i.e., 22 time series per group. If the detection of outliers and correlograms revealed a pattern of non-randomness that was only time-locked to a single, specific event in the normalized time series, then an experimental effect would be inferred beyond the inherent variability of H-reflex responses. Tibial nerve F-wave responses were included to determine if any new information about central nervous function following a HVLA SM procedure could be ascertained. Time series analyses of H(max)/M(max) ratios, pre-post L5-S1 HVLA SM, substantiated the hypothesis that the specific aspects of the manipulative thrust lead to a greater attenuation of the H(max)/M(max) ratio as compared to the non-specific aspects related to the postural perturbation and joint pre-loading. The attenuation of the H(max)/M(max) ratio following the HVLA SM procedure was reliable and may hold promise as a translational tool to measure the consistency and accuracy of protocol implementation involving SM in clinical trials research. F-wave responses were not sensitive to mechanical perturbations of the lumbar spine.

Effects of Footwear Comfort Perception on the Neuromuscular Control of Balance

ABSTRACT The purpose of this research was to determine the effects of footwear comfort perception on the gain of the gastrocnemius H-reflex response during single leg balance tasks. Subjects performed single leg balance tasks while wearing aerobic sneakers with two different pairs of shoe insoles that were subjectively rated for comfort using a reliable 150 mm visual analog scale. The primary outcome was the consistency of decreasing the gain of the gastrocnemius H-reflex with increasing balance task complexity as a function of footwear comfort perception. Among the asymptomatic subjects (n = 11), H-reflex gain significantly decreased by 19% and 10% from balancing on a stable surface to an unstable surface for the shoe-brand and replacement insoles, respectively (p < .05). Among the subjects with musculoskeletal disorders (n = 13), H-reflex gain significantly decreased by 10% from balancing on a stable surface to an unstable surface when wearing custom-molded foot orthotics, but H-reflex gain significantly increased by 27% from balancing on a stable surface to an unstable surface when wearing replacement insoles (p < .05). Decreases in footwear comfort perception may negatively impact the attenuation of gastrocnemius H-reflex gain that contributes to the neuromuscular control of challenging balance tasks.