Comparison of paraspinal cutaneous temperature measurements between subjects with and without chronic low back pain.

OBJECTIVE: The purpose of this study was to evaluate the effects of chiropractic manipulative treatment on paraspinal cutaneous temperature (PCT) for subjects with chronic low back pain and compare these PCT findings to subjects without chronic low back pain. METHODS: Two groups were created, a symptomatic treatment group (subjects with chronic low back pain, n = 11, 7 males, 4 females) and an asymptomatic, nontreatment group (asymptomatic subjects, n = 10, 6 males, 4 females). Outcomes included the modified Oswestry questionnaire and PCT measurements in the prone position after an 8-minute acclimation period. The treatment group received 9 chiropractic spinal instrument-based manipulative treatments over 2 weeks. Reevaluation was done 2 weeks after the initial evaluation for both groups. RESULTS: The preintervention Oswestry results (29.8% ± 11.8%) for the treatment group were higher than the asymptomatic group (10.2% ± 10.6%). The postintervention Oswestry results for the treatment group were 14.20 % ± 11.5%. The resulting Cohen's effect size of the spinal manipulation on the Oswestry evaluation is 0.58. The preintervention PCT showed higher temperature for the nontreatment group compared with the treatment group. Comparing the levels associated with low back pain, the nontreatment group PCT was stable, varying from 0.01°C to 0.02°C, whereas the treatment group PCT varied from 0.10°C to 0.18°C. The treatment group postintervention PCT showed an increase in temperature after the 9 visits; however, this did not reach the values of the asymptomatic group. CONCLUSION: The PCT readings for subjects with chronic low back pain were lower than the asymptomatic, nontreatment group. The PCT temperature of the treatment group increased after 9 treatments.

Effect of electrical stimulation on lipolysis of human white adipocytes.

The goal of the present study was to investigate the effect of 30 min of electrical stimulation on the activation of lipolysis in human white adipocytes. Two stimulation protocols (S1, S2) were conducted in vitro on isolated human white adipocytes. Subcutaneous adipose tissue was obtained from female subjects undergoing abdominal adipose tissue reduction. Adipose tissue of 10 female subjects (mean age, 38.7 ± 9.1 years) and 6 female subjects (mean age, 37.2 ± 11.3 years) was obtained for S1 and S2, respectively. All subjects fasted overnight before tissue removal. The control conditions were a basal and a ß-adrenergic stimulation (isoproterenol (ISO), 10(-6) mol·L(-1)) of lipolysis. For S1, the 3 electrostimulation conditions consisted of a monopolar square-wave pulse current for 30 min at intensities of 4, 8, and 20 mA, respectively. In S2, the 2 electrostimulation conditions consisted of a bipolar square-wave alternating current for 30 min at intensities of 4 and 6 mA, respectively. Fat cell lipolysis was measured by quantifying the release of glycerol from adipocytes for 3 trials in each experimental condition. For S1, 4 mA significantly increased lipolysis 1.5 times over basal values (p ≤ 0.01), 8 mA and 20 mA did not increase lipolysis significantly, and no significant difference (p > 0.05) was found between ISO and 4 mA. For S2, 4 mA (p ≤ 0.05) and 6 mA (p ≤ 0.01) significantly increased lipolysis by 1.8 and 2.3 times above basal, respectively. Our results demonstrate that both monopolar (4 mA) and bipolar (4 and 6 mA) electrical stimulations significantly activated in vitro lipolysis. Our findings suggest the existence of a new lipolytic pathway that may involve K(v) channels shown to exist in human white adipocytes.

Paraspinal cutaneous temperature modification after spinal manipulation at L5.

OBJECTIVE: The purpose of this study was to investigate local paraspinal cutaneous temperature (CT) modifications after spinal manipulative therapy at L5. METHODS: Twenty subjects with acute low back symptoms were randomly assigned to either a treatment or a sham group (n = 10 per group). Subjects underwent an 8-minute acclimatizing period. Temperature was measured bilaterally with infrared cameras at the L5 level. In the treatment group, a traditional chiropractic manipulation (lumbar roll technique with a pisiform contact on the ipsilateral mamillary of L5) was delivered, whereas with the sham group, the same technique was used, but no thrust was applied. Cutaneous temperature control measurements were taken 2 minutes before (t(-2)) and immediately after the intervention (t(0)) and at 1, 3, 5, and 10 minutes postintervention (t(1), t(3), t(5), and t(10), respectively). RESULTS: At t(0), CT in the treatment group on the treatment side (ipsilateral side) warmed up by 0.2 degrees F, whereas in the sham group, there were no significant temperature modifications on either side. At t(3) relative to t(0), CT in the treatment group on the treatment side warmed by approximately 0.6 degrees F, whereas the contralateral side (nontreatment side) cooled. In the treatment group, significant differences were noted between sides (F = 13.36, P = .002, P = .932) and sides x times (F = 2.97, P = .016, P = .838). CONCLUSION: The effects of a lumbar spine manipulation appear noticeable by changes in paraspinal CT measurements at the level of L5. However, the meaning and mechanisms of CT modifications at L5 are still being investigated.

Consistency of cutaneous thermal scanning measures using prone and standing protocols: a pilot study.

OBJECTIVE: The goal of this pilot study was to measure paraspinal cutaneous temperature (PCT) in the prone vs standing position. METHODS: Ten symptom-free participants were evaluated. Paraspinal cutaneous temperature was recorded. Subjects were acclimated to the treatment room in a prone position for 8 minutes before the PCT was measured. After the prone PCT reading, patients stood. A standing PCT measurement was then taken. RESULTS: Paraspinal cutaneous temperature was marginally warmer when subjects were standing vs prone (PCT difference, 0.25 degrees C +/- 0.64 degrees C and 0.62 degrees C +/- 0.67 degrees C for left and right sides, respectively). The right and left side differential was the same in the prone and standing positions. There was a positive Pearson correlation (0.802-0.803; P < .000) between the standing and prone positions for both left and right sides. CONCLUSION: There are no differences between the prone or standing PCT measures if symptom-free subjects are given 8 minutes to acclimate before recording PCT measures.

Inflammatory response following a short-term course of chiropractic treatment in subjects with and without chronic low back pain.

OBJECTIVE: Inflammatory markers interleukin-6 (IL-6) and C-reactive protein (CRP) have not been evaluated in response to a short course of lumbar spinal manipulation. The purpose of this study is to observe the responses of inflammatory markers (IL-6 and CRP) after a series of 9 chiropractic spinal manipulations. METHODS: Twenty-one participants were assigned to a treatment or a control group. Only the treatment group received 9 chiropractic interventions. Pre- and postintervention measures were recorded for blood samples for detection of proinflammatory cytokines IL-6 and CRP. RESULTS: Mediators of inflammation (IL-6 and high-sensitivity CRP) were modified by the intervention received in the treatment group, and the effect size demonstrated a tendency toward the control group values. CONCLUSION: A total of 9 chiropractic lower back manipulations caused the mediators of inflammation to present a normalization response in individuals suffering from chronic low back pain.

Heart rate variability modulation after manipulation in pain-free patients vs patients in pain.

BACKGROUND: The purpose of this study was to examine heart rate variability (HRV) in the presence or the absence of pain in the lower back, while receiving one chiropractic treatment at L5 from either a manually assisted mechanical force (Activator) or a traditional diversified technique spinal manipulation. METHODS: A total of 51 participants were randomly assigned to a control (n = 11), 2 treatment, or 2 sham groups (n = 10 per group). Participants underwent an 8-minute acclimatizing period. The HRV tachygram (RR interval) data were recorded directly into a Suunto watch (model T6; FitzWright Company Ltd, Langley, British Columbia, Canada). We analyzed the 5-minute pretreatment and posttreatment intervals. The spectral analysis of the tachygram was performed with Kubios software. RESULTS: All groups decreased in value except the control group that reacted in the opposite direction, when comparing the pretests and posttests for the high-frequency component. The very low frequency increased in all groups except the control group. The low frequency decreased in all groups except the sham pain-free group. The low frequency-high frequency ratio decreased in the treatment pain group by 0.46 and in the sham pain-free group by 0.26. The low frequency-high frequency ratio increase was 0.13 for the sham pain group, 0.04 for the control group, and 0.34 for the treatment pain-free group. The mean RR increased by 11.89 milliseconds in the sham pain-free group, 18.65 milliseconds in the treatment pain group, and 13.14 milliseconds in the control group. The mean RR decreased in the treatment pain-free group by 1.75 milliseconds and by 0.01 milliseconds in the sham pain group. CONCLUSION: Adjusting the lumbar vertebrae affected the lumbar parasympathetic nervous system output for this group of participants. Adaptation in the parasympathetic output, reflected by changes in high frequency, low frequency, and very low frequency, may be independent of type of adjustment. Therefore, the group differences found in the modulation of the HRV would seem to be related to the presence or absence of pain. The autonomic nervous system response may be specific and sensitive to its effectors organ.

Effects of a manually assisted mechanical force on cutaneous temperature.

OBJECTIVE: Digitized infrared segmental thermometry (DIST) is a tool used for measuring cutaneous temperature (CT). This project ascertains the effect of a manually assisted mechanical force producing a chiropractic adjustment in the lumbar spine after the Activator Methods Chiropractic Technique on CT during 2 different time recording periods (TRPs). METHODS: Sixty-six healthy subjects (36 women and 30 men) without acute low back conditions or symptoms were recruited. Subjects were randomly divided into 2 groups based on the length of the acclimatization period (8 or 30 minutes; TRP(8) and TRP(30), respectively). In turn, each recording period group was divided into 3 subgroups (n = 11 per subgroup): treatment, sham, and control subgroups. Bilateral DIST was conducted at L-4 (TRP(30)) and L-5 (TRP(8)) using infrared cameras (Subluxation Station Insight 7000; Chiropractic Leadership Alliance, Mahwah, NJ). RESULTS: Before treatment (t(-0.5)), the TRP(8) CT was significantly different between the ipsilateral and the contralateral sides for all subgroups. At 10 minutes (t(10)) after intervention, CT increased significantly (P < .05) for the treatment group but not for the sham and control groups. In contrast, there were no significant differences in the TRP(30) CT before treatment between the ipsilateral and the contralateral sides; but at t(10), CT was significantly (P < .05) greater for all 3 subgroups compared with preintervention CT. CONCLUSION: Contacting the skin with the instrument with (treatment group TRP(30)) or without (sham group TRP(30)) a thrust with a sustained pressure stronger than the loading principle taught in the Activator Methods Chiropractic Technique protocol or a thrust respecting the standard loading principle (treatment group TRP(8)) of the instrument produced a CT cooling immediately after the adjustment. Furthermore, we observed that when contacting the skin with the instrument with a thrust respecting the standard loading principle (treatment group TRP(8)) of the instrument, it produced a secondary cooling at t(5) followed by a rewarming at t(10). Finally, contacting the skin with the instrument without a thrust and respecting the standard loading principle (sham TRP(8)) of the instrument did not produce a CT change.

Digitized infrared segmental thermometry: time requirements for stable recordings.

OBJECTIVES: Digitized infrared segmental thermometry (DIST) is a method for measuring and recording skin surface body temperatures. The project evaluated the required length of time for patients to acclimatize their core body temperature to ambient conditions to obtain stable DIST readings. METHODS: Seventeen subjects were allowed a 20-minute acclimatizing period in a temperature-controlled room. The bilateral DIST temperature was measured with thermistors in combination with infrared cameras (IRCs) at the C4 and L4 levels. All IRC temperatures were recorded after a 20-minute stabilization period. The room temperature and relative humidity were recorded throughout all trials. The acclimatization trend was computed from the 20- to 24-minute period for the IRCs, and the acclimatization trend was computed continuously for a total of 30 minutes (at 2-minute intervals) for 5 days. RESULTS: We discovered a stabilization trend in the early trial stages, with the thermistor recordings between 8 and 16 minutes. The IRC trend was also conclusive for the core temperature requirements. CONCLUSIONS: This study determined a core body temperature acclimatization trend tested among patients using thermistor recordings in a controlled environment. Based on these findings, we recommend acclimatization in a temperature- and humidity-controlled environment for a minimum 8-minute period, followed by an 8-minute maximum recording period with the patient in a prone position to obtain accurate DIST recordings.

Vastus medialis: anatomical and functional considerations and implications based upon human and cadaveric studies.

OBJECTIVE: To provide an electrophysiological and functional description of the vastus medialis (VM) and contrast it to an anatomical description. METHODS: Motor points of all superficial portions of the quadriceps were identified on the dominant side of 8 human subjects and electrically stimulated to achieve a light contraction to trace and measure the orientation of the fibers. Electromyography of the VM was then recorded over 2 motor points during isometric and isokinetic maximum knee extensions. An independent laboratory dissected 39 cadaveric specimens focusing on fiber orientations and distal insertions of the VM. RESULTS: Results revealed 5 motor points for the quadriceps: 1 point for the vastus lateralis, 1 point for the rectus femoris (RF), and 3 points for the VM. The 3 VM motor points suggest 3 separate groups of fibers: proximal (pf), median (mf), distal (df). Fiber orientations ranged from 45 degrees for VMpfs to 55 degrees for VMdfs. Motor point stimulation and anatomical dissection clearly showed that the VMpfs and VMmfs were inserted on a tendon common to the RF, whereas VMdfs were attached directly to the medial aspect of the patella. Furthermore, the VMpfs were more active (P < .05) than VMdfs during maximum knee extensions. CONCLUSION: The anatomy, motor points, and electromyography clearly support an important distinction between the VMpfs and VMdfs. The role of the VMpfs would be one of assisting the RF in knee extension, whereas the VMdfs would track the patella medially without participating in knee extension. Because of these anatomical and functional differences, the VMpfs and VMdfs should be addressed very differently during quadriceps rehabilitation in patellofemoral dysfunctions.

Validity of infrared thermal measurements of segmental paraspinal skin surface temperature.

OBJECTIVE: The purpose of this study was to evaluate the validity of thermal measurements by infrared camera thermometry. METHODS: Seventeen subjects underwent a 30-minute acclimatizing period in a controlled environment room. Thermal recordings were executed at the levels of C4 and L4. Fifteen recordings per segment were acquired in an alternating mode that always started at L4. Each subject was required to participate on 5 occasions. The exclusion criteria for the subjects included the following: no inflammatory disease or fever, no consumption of beverages containing caffeine, and no participation in physical activity 2 hours before the recording session; female subjects could not be menstruating on a day of recording. RESULTS: A total of 2550 recordings for the cervical area and the lumbar area was recorded. Strong significant correlations were found for the left (r = .77) and right (r = .71) lumbar sections (P < .0001) whereas weaker significant correlations were observed for the left (r = .56) and right (r = .63) cervical areas (P < .0001). The limits of agreement (Bland-Altman) showed good relationships but poor interchangeability. CONCLUSIONS: In this study, the infrared cameras showed that they were valid tools in a controlled environment; however, the technique for the cervical measurements needs to be reassessed.

Balance training following stroke: effects of task-oriented exercises with and without altered sensory input.

The purpose of this study was to compare the effects of a task-oriented exercise program with and without altered sensory input on postural stability in subjects with stroke. Sixteen hemiparetic subjects, at least 6 months post-stroke, were randomly assigned to the experimental or control group, and participated in an 8-week task-oriented exercise program focusing on balance and mobility exercises. Exercises were performed under normal conditions by the control group, and under conditions of vision and surface manipulation by the experimental group. Pre- and post-test assessments involved the measurement of the center of pressure (COP) displacement during double-legged stance and sit-to-stand under four sensory conditions: (1) eyes open, normal surface; (2) eyes open, soft surface; (3) eyes closed, normal surface; and (4) eyes closed, soft surface, as well as the 10-m walking test. Results showed significant improvements (P<0.05) in COP displacement under sensory conditions (1) and (2) for the experimental group only, and limited changes for the sit-to-stand in both groups after training. Significant improvements (P<0.05) were also found in both groups for the walking test. It is concluded that a task-oriented exercise program, assisted by sensory manipulation, is more effective at improving the standing balance of stroke subjects than a conventional task-oriented program.

Reliability of the FCR H-reflex.

This study examined the intraclass reliability of the latency and amplitude of the Hoffmann reflex (H-reflex) in the flexor carpi radialis (FCR). The stability and consistency of the latency and peak-to-peak amplitude of the H-reflex were assessed across four test sessions. The FCR H-reflex was evoked in 39 volunteers (20 males and 19 females) on four separate days. The maximum amplitude of the motor response (Mmax) was determined each day and 10 responses were recorded at that stimulus intensity. The H-reflex was then evoked at an intensity corresponding to 5% of Mmax (H5%) and 10 recordings were obtained. The latency of the H-reflex and the peak-to-peak amplitude of both Mmax and H5% were calculated for each trial. Determination of reliability involves the consideration of both the stability and consistency of the measures. The reliability of the measures in this investigation was assessed using an analysis of variance and corresponding Lindquist intraclass correlation coefficient (ICC) model. In contrast to previous investigations, the H-reflex was evoked without facilitation in 95% (37/39) of the subjects tested. Statistical evaluation revealed that the latency and amplitude of the H-reflex, as well as the amplitude of Mmax, were both stable and consistent across the four test days. The ICC for Mmax was 0.97. The ICC for H5% was 0.92, and for latency of the H-reflex was 0.89. It was shown that the H-reflex can be easily evoked in the FCR and that the latency and amplitude of these recordings are highly reliable. The demonstration that the H-reflex can be easily and consistently evoked in the FCR has important clinical implications. It provides a tool for clinicians to assess the C7 level of the spinal cord and median nerve function.

Reliability of the motor evoked potentials elicited through magnetic stimulation at three sites.

BACKGROUND: Motor evoked potentials (MEPs) obtained from magnetic stimulation allow the measurement of the excitability of motor nerve cells. Although this technique is becoming widely used, its reliability has yet to be established. OBJECTIVE: To determine the reliability of MEPs and evaluate their stability. DESIGN: Subjects received magnetic stimulation at 3 different sites: cranial, cervical, and peripheral. Three stimulations were given at each site. Stimulations were given under 4 conditions: eyes open or closed and with or without controlled mental activity. SETTING: The study was performed in a research laboratory setting. PARTICIPANTS: Nine healthy subjects (mean age = 21 years +/- 0.9), asymptomatic of any neural or musculoskeletal dysfunctions. MAIN OUTCOME MEASURES: Normalized peak-to-peak amplitude of MEPs at the opponens pollicis muscle. RESULTS: Intraclass correlations were high for all conditions (R > 0.90). The amplitude of the MEPs elicited from the transcranial site during the controlled mental activity condition was increased by 26.6% (P =.017). No other significant differences (P >.05) were obtained among the other conditions. CONCLUSION: Intraclass correlation results reveal that MEP measurements are highly reliable in a controlled environment. The increase of MEPs during the controlled mental activity condition could be attributed to an elevation of neural activity of different nonmotor areas of the brain increasing corticospinal excitability.

The effect of Trager therapy on the level of evoked stretch responses in patients with Parkinson's disease and rigidity.

OBJECTIVE: To quantify changes of evoked stretch responses (ESR) in the most rigid arm of patients with Parkinson's disease (PD) after Trager therapy. METHODS: Gentle rocking motion associated with this type of manual therapy was imparted to the upper limbs and body of 30 patients for 20 minutes. A pretest and 2 posttests (at 1 and 11 minutes after the treatment, respectively) were performed, consisting of electromyographic (EMG) recordings of the flexor carpi radialis and extensor digitorum communis while the patient's wrist was passively flexed and extended with an amplitude of 60 degrees and a frequency of 1 Hz. Patients received the treatment on the most rigid side of their bodies (ipsi-group) or on the contralateral side (contra-group). Half of patients in each group received the treatment while lying supine on a massage table (ipsi- and contra-supine) or sitting in a chair (ipsi- and contra-sitting). RESULTS: In general, the level of ESR were reduced by 36% immediately after treatment and remained 32% lower than pretest values 11 minutes after treatment (F = 41.45, P <.05). Patients who received the treatment lying supine benefited from a 42% reduction of ESR (F = 4.07, P <.05). The side on which the treatment was performed did not significantly influence the outcome of the treatment (F = 0.50, P >.05). However, post hoc analysis of the triple interaction (test x side x position) indicated that the sitting position was much less efficient for sustained contralateral effect (P >.05). CONCLUSIONS: Results from the present study strongly suggest that it is possible to modify the level of ESR by using Trager therapy. This stretch reflex inhibition may induce a reduction of the muscle rigidity seen in these patients. The present results may eventually lead to the development of a specific complementary therapy for patients with Parkinson's disease and rigidity.