Archive for category Neurophysiological

Resolution of Lower Limb Sensory Polyneuropathy In A 63-Year-Old Male Receiving Activator Methods Chiropractic Technique For The Correction Of Vertebral Subluxation

August 15, 2017 Activator Methods Chiropractic Technique: General Articles, Case Studies, Neurophysiological,

Abstract

Objective:

To describe the resolution of low-grade sensory polyneuropathy and the improvements in spinal function in a 63-year-old male receiving Activator Methods Chiropractic Technique (AMCT) to correct vertebral subluxation.

Clinical features:

A 63-year-old male with a 4-year history of bilateral lower limb sensory polyneuropathy, previously diagnosed by nerve conduction testing. Postural alterations, moderate reduction in cervical and lumbar range of motion (ROM), and positive sensory changes were found in conjunction with vertebral subluxation throughout the spine and moderate lumbar degenerative changes present on x-ray.

Results:

Chiropractic care using AMCT was provided for the correction of vertebral and extremity subluxations. The patient demonstrated subjective improvements in sensation in the lower limb, and objective improvement in posture, in measured spinal ROM, neurological assessment and a reduction in vertebral subluxation.

Conclusion:

A course of chiropractic care using AMCT was associated with resolution of lower limb sensory polyneuropathy, improvement in objective posture, spinal ROM and neurological assessment with reduction in vertebral subluxation. More research is needed to investigate the role chiropractors may play in helping similar patients so as to inform clinical practice and future higher-level research designs

Chiropr J Australia 2017;45:217-228
Author information: David Russell, BSc (Psych), BSc (Chiro), Cert TT

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Abstract STUDY DESIGN: Comparative study using robotic replication of spinal manipulative therapy (SMT) vertebral kinematics together with serial dissection. OBJECTIVE: The aim of this study was to quantify loads created in cadaveric spinal tissues arising from three different forms of SMT application. SUMMARY OF BACKGROUND DATA: There exist many distinct methods by which to apply […]

Spinal Tissue Loading Created by Different Methods of Spinal Manipulative Therapy Application.

May 1, 2017 Activator V, Animal Models, Neurophysiological,

Abstract

STUDY DESIGN:

Comparative study using robotic replication of spinal manipulative therapy (SMT) vertebral kinematics together with serial dissection.

OBJECTIVE:

The aim of this study was to quantify loads created in cadaveric spinal tissues arising from three different forms of SMT application.

SUMMARY OF BACKGROUND DATA:

There exist many distinct methods by which to apply SMT. It is not known presently whether different forms of SMT application have different effects on spinal tissues. Should the method of SMT application modulate spinal tissue loading, quantifying this relation may help explain the varied outcomes of SMT in terms of effect and safety.

METHODS:

SMT was applied to the third lumbar vertebra in 12 porcine cadavers using three SMT techniques: a clinical device that applies forces through a hand-held instrument (INST), a manual technique of applying SMT clinically (MAN) and a research device that applies parameters of manual SMT through a servo-controlled linear actuator motor (SERVO). The resulting kinematics from each SMT application were tracked optically via indwelling bone pins. The L3/L4 segment was then removed, mounted in a parallel robot and the resulting kinematics from SMT replayed for each SMT application technique. Serial dissection of spinal structures was conducted to quantify loading characteristics of discrete spinal tissues.

RESULTS:

In terms of load magnitude, SMT application with MAN and SERVO created greater forces than INST in all conditions (P < 0.05). Additionally, MAN and SERVO created comparable posterior forces in the intact specimen, but MAN created greater posterior forces on IVD structures compared to SERVO (P < 0.05).

CONCLUSION:

Specific methods of SMT application create unique vertebral loading characteristics, which may help explain the varied outcomes of SMT in terms of effect and safety.

Spine (Phila Pa 1976). 2017 May 1;42(9):635-643. PMID: 28146021 

Author information: Funabashi M, Nougarou F, Descarreaux M, Prasad N, Kawchuk GN. University of Alberta, Edmonton, AB, Canada.

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Abstract Objective The aim of this study was to investigate changes in brain and muscle glucose metabolism that are not yet known, using positron emission tomography with [18F]fluorodeoxyglucose ([18F]FDG PET). Methods Twenty-one male volunteers were recruited for the present study. [18F]FDG PET scanning was performed twice on each subject: once after the spinal manipulation therapy […]

Glucose Metabolic Changes in the Brain and Muscles of Patients with Nonspecific Neck Pain Treated by Spinal Manipulation Therapy: A [18F]FDG PET Study

January 12, 2017 Activator II, Cervical Spine, Neurophysiological,

Figure 3: Regional activation (left) and deactivation (right) after spinal manipulation therapy (SMT) using an activator adjusting instrument. Glucose metabolism is increased in regions including the anterior cingulate cortex and cerebellar vermis but is relatively reduced in many sites, including the prefrontal cortex, after SMT. The voxel height threshold is p<0.05, corrected for multiple comparisons; the extent threshold is 10 voxels minimum

Abstract

Objective

The aim of this study was to investigate changes in brain and muscle glucose metabolism that are not yet known, using positron emission tomography with [18F]fluorodeoxyglucose ([18F]FDG PET).

Methods

Twenty-one male volunteers were recruited for the present study. [18F]FDG PET scanning was performed twice on each subject: once after the spinal manipulation therapy (SMT) intervention (treatment condition) and once after resting (control condition). We performed the SMT intervention using an adjustment device. Glucose metabolism of the brain and skeletal muscles was measured and compared between the two conditions. In addition, we measured salivary amylase level as an index of autonomic nervous system (ANS) activity, as well as muscle tension and subjective pain intensity in each subject.

Results

Changes in brain activity after SMT included activation of the dorsal anterior cingulate cortex, cerebellar vermis, and somatosensory association cortex and deactivation of the prefrontal cortex and temporal sites. Glucose uptake in skeletal muscles showed a trend toward decreased metabolism after SMT, although the difference was not significant. Other measurements indicated relaxation of cervical muscle tension, decrease in salivary amylase level (suppression of sympathetic nerve activity), and pain relief after SMT.

Conclusion

The findings of the present study demonstrate how stimuli to the mechanoreceptors of the joints and skin during SMT are processed in the brain. Brain processing after SMT may lead to physiological relaxation via a decrease in sympathetic nerve activity.

Evidence-Based Complementary and Alternative Medicine, Volume 2017 (2017)

Author information: Akie Inami, Takeshi Ogura, Shoichi Watanuki, Md. Mehedi Masud, Katsuhiko Shibuya, Masayasu Miyake, Rin Matsuda, Kotaro Hiraoka, Masatoshi Itoh, Arlan W. Fuhr, Kazuhiko Yanai, and Manabu Tashiro. Tohoku University, Sendai, Japan.

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Neural Response During a Mechanically Assisted Spinal Manipulation in an Animal Model: A Pilot Study

April 6, 2015 Activator IV, Animal Models, Neurophysiological, Research,

Abstract

Introduction:

Mechanoreceptor stimulation is theorized to contribute to the therapeutic efficacy of spinal manipulation. Use of mechanically-assisted spinal manipulation (MA-SM) devices is increasing among manual therapy clinicians worldwide. The purpose of this pilot study is to determine the feasibility of recording in vivo muscle spindle responses during a MA-SM in an intervertebral fixated animal model.

Methods:

Intervertebral fixation was created by inserting facet screws through the left L5-6 and L6-7facet joints of a cat spine. Three L6 muscle spindle afferents with receptive fields in back muscles were isolated. Recordings were made during MA-SM thrusts delivered to the L7 spinous process using an instrumented Activator IV clinical device.

Results:

Nine MA-SM thrusts were delivered with peak forces ranging from 68-122N and with thrust durations of less than 5ms. High frequency muscle spindle discharge occurred during MA-SM. Following the MA-SM, muscle spindle responses included returning to pre-manipulation levels, slightly decreasing for a short window of time, and greatly decreasing for more than 40s.

Conclusion:

This study demonstrates that recording in vivo muscle spindle response using clinical MA-SM devices in an animal model is feasible. Extremely short duration MA-SM thrusts (<5ms) can have an immediate and/or a prolonged (> 40s) effect on muscle spindle discharge. Greater peak forces during MA-SM thrusts may not necessarily yield greater muscle spindle responses. Determining peripheral response during and following spinal manipulation may be an important step in optimizing its’ clinical efficacy. Future studies may investigate the effect of thrust dosage and magnitude.

J Nov Physiother Phys Rehabil 2015 Apr;2(3): 047-054.

Author information: Reed WR, Liebschner MAK, Sozio RS, Pickar JG, Gudavalli MR. Palmer Center for Chiropractic Research, Davenport, IA, USA.

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In Vitro Biomechanical Evaluation of Single Impulse and Repetitive Mechanical Shockwave Devices Utilized for Spinal Manipulative Therapy

December 1, 2014 Activator IV, Activator Methods Chiropractic Technique: General Articles, Activator V, Biomechanical, Neurophysiological, Research, Spine,

Abstract

OBJECTIVE:

The objectives of this study were to determine the ability of several commercial shockwave devices to achieve a desired thrust profile in a benchtop setting, determine the thrust profile in a clinical analog, and determine the influence of operator experience level on device performance.

INTERVENTION AND OUTCOME:

We conducted two different types of testing: (1) bench testing to evaluate the devices themselves, and (2) clinical equivalent testing to determine the influence of the operator.

CONCLUSIONS:

The results indicated a significant dependence of thrust output on the compliance of the test media. The Activator V-E device matched the ideal half-sine thrust profile to 94%, followed by the Impulse device (84%), the Activator IV/FS (74%), and the Activator II (48%). While most devices deviated from the ideal profile on the return path, the Impulse device exhibited a secondary peak. Moreover, the Activator V-E device provided evidence that the device performs consistently despite operator experience level.This has been a major concern in manual spinal manipulation. Based on our results, a hyper-flexible spine would receive a lower peak thrust force than a hypo-flexible spine at the same power setting. Furthermore, a hand-held operation further reduced the peak thrust force as it increased the system compliance. However, that influence was dissimilar for the different devices. Although controlled clinical trials are needed to determine the correlation between thrust profile and clinical outcome, already ongoing clinical studies indicate an improved patient satisfaction due to reduced treatment pain when devices are used with a thrust characteristic closer to an ideal sine wave.

Annals of Biomedical Engineering, Vol. 42, No. 12, December 2014 ( 2014) pp. 2524–2536 DOI: 10.1007/s10439-014-1115-4

Author information: Liebschner, Michael A. K.; Chun, Kwonsoo; Kim, Namhoon; and Ehni, Bruce

Department of Neurosurgery, Baylor College of Medicine, Houston, TX, USA; Research Service Line, Michael E. DeBakey VA Medical Center, Houston, TX, USA;  Exponent Failure Analysis, Houston, TX, USA;  Department of Pediatrics Cardiology, Baylor College of Medicine, Houston, TX, USA; and Neurosurgery Service Line, Michael E. DeBakey VA Medical Center, Houston, TX, USA

In Vitro Biomechanical Evaluation of Single Impulse and Repetitive

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Neural responses to the mechanical parameters of a high-velocity, low-amplitude spinal manipulation: effect of preload parameters.

February 1, 2014 Animal Models, Neurophysiological, Research,

Abstract

OBJECTIVE:

The purpose of this study was to determine how the preload that precedes a high-velocity, low-amplitude spinal manipulation (HVLA-SM) affects muscle spindle input from lumbar paraspinal muscles both during and after the HVLA-SM.

METHODS:

Primary afferent activity from muscle spindles in lumbar paraspinal muscles were recorded from the L6 dorsal root in anesthetized cats. High-velocity, low-amplitude spinal manipulation of the L6 vertebra was preceded either by no preload or systematic changes in the preload magnitude, duration, and the presence or absence of a downward incisural point. Immediate effects of preload on muscle spindle responses to the HVLA-SM were determined by comparing mean instantaneous discharge frequencies (MIF) during the HVLA-SM’s thrust phase with baseline. Longer lasting effects of preload on spindle responses to the HVLA-SM were determined by comparing MIF during slow ramp and hold movement of the L6 vertebra before and after the HVLA-SM.

RESULTS:

The smaller compared with the larger preload magnitude and the longer compared with the shorter preload duration significantly increased (P = .02 and P = .04, respectively) muscle spindle responses during the HVLA-SM thrust. The absence of preload had the greatest effect on the change in MIF. Interactions between preload magnitude, duration, and downward incisural point often produced statistically significant but arguably physiologically modest changes in the passive signaling properties of the muscle spindle after the manipulation.

CONCLUSION:

Because preload parameters in this animal model were shown to affect neural responses to an HVLA-SM, preload characteristics should be taken into consideration when judging this intervention’s therapeutic benefit in both clinical efficacy studies and in clinical practice.

J Manipulative Physiol Ther. 2014 Feb;37(2):68-78. [PMID:24387888]

Author information: Reed WR, Long CR, Kawchuk GN, Pickar JG.  Palmer Center for Chiropractic Research, Palmer College of Chiropractic, Davenport, Iowa.

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Effects of thrust amplitude and duration of high velocity low amplitude spinal manipulation on lumbar muscle spindle responses to vertebral position and movement.

February 1, 2013 Animal Models, Neurophysiological, Research,

Abstract

OBJECTIVE:

Mechanical characteristics of high-velocity, low-amplitude spinal manipulations (HVLA-SMs) can vary. Sustained changes in peripheral neuronal signaling due to altered load transmission to a sensory receptor’s local mechanical environment are often considered a mechanism contributing to the therapeutic effects of spinal manipulation. The purpose of this study was to determine whether variation in an HVLA-SM’s thrust amplitude and duration alters the neural responsiveness of lumbar muscle spindles to either vertebral movement or position.

METHODS:

Anesthetized cats (n = 112) received L6 HVLA-SMs delivered to the spinous process. Cats were divided into 6 cohorts depending upon the peak thrust force (25%, 55%, 85% body weight) or thrust displacement (1, 2, 3 mm) they received. Cats in each cohort received 8 thrust durations (0-250 milliseconds). Afferent discharge from 112 spindles was recorded in response to ramp and hold vertebral movement before and after the manipulation. Changes in mean instantaneous frequency (∆MIF) during the baseline period preceding the ramps (∆MIFresting), during ramp movement (∆MIFmovement), and with the vertebra held in the new position (∆MIFposition) were compared.

RESULTS:

Thrust duration had a small but statistically significant effect on ∆MIFresting at all 6 thrust amplitudes compared with control (0-millisecond thrust duration). The lowest amplitude thrust displacement (1 mm) increased ∆MIFresting at all thrust durations. For all the other thrust displacements and forces, the direction of change in ∆MIFresting was not consistent, and the pattern of change was not systematically related to thrust duration. Regardless of thrust force, displacement, or duration, ∆MIFmovement and ∆MIFposition were not significantly different from control.

CONCLUSION:

Relatively low-amplitude thrust displacements applied during an HVLA-SM produced sustained increases in the resting discharge of paraspinal muscle spindles regardless of the duration over which the thrust was applied. However, regardless of the HVLA-SM’s thrust amplitude or duration, the responsiveness of paraspinal muscle spindles to vertebral movement and to a new vertebral position was not affected.

J Manipulative Physiol Ther. 2013 Feb;36(2):68-77. [PMID:23499141]

Author information: Cao DY, Reed WR, Long CR, Kawchuk GN, Pickar JG. Palmer Center for Chiropractic Research, Davenport, IA 52803, USA.

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Changes in pressure pain thresholds and Basal electromyographic activity after instrument-assisted spinal manipulative therapy in asymptomatic participants: a randomized, controlled trial.

July 1, 2012 Activator IV, Clinical Trials, Neurophysiological, Research,

Abstract

OBJECTIVE:

The purpose of this study was to investigate the effects of instrument-assisted spinal manipulative therapy (SMT) targeted to the low-back region on changes in pressure pain thresholds (PPTs) and basal electromyographic activity (BEA) in asymptomatic participants.

METHODS:

A repeated-measures, single-blind, randomized trial was conducted on 30 participants, 19 men and 11 women (mean age, 24.5±3.9 years), without a current history of low-back pain. Each participant attended all 2 treatment group sessions and received instrument-assisted SMT or a sham manipulation procedure. Instrument-assisted SMT was administered using the Activator Method protocol. Bilateral PPT levels over L5-S1 zygapophyseal joints, L5 dermatome, and first dorsal interossei in the hand and bilateral BEA of low back and neck region were assessed pre- and posttreatment by an assessor blinded to the treatment allocation of the participant. A 3-way analysis of variance with time (pre-post) and side (ipslateral, contralateral to the intervention) as within-group variable and intervention (manipulation or sham) as between-group variable was used to evaluate changes in PPT. A paired sample t test was used to analyze the differences between pre- and posttreatment in BEA.

RESULTS:

The group vs time interaction was statistically significant for PPT irrespective of the site tested or the side treated. Participants receiving the instrument-assisted SMT experienced greater improvement in PPT when compared with the control group. Paired sample t tests for BEA only show an immediate decrease in BEA of the paraspinal muscle on the pelvic deficiency side of the low-back region.

CONCLUSIONS:

The application of instrument-assisted SMT resulted in an immediate and widespread hypoalgesic effect with local muscle relaxation in asymptomatic participants. It is hypothesized that therapeutic mechanisms, either segmental or central, may be involved in the therapeutic effects of instrument-assisted SMT.

J Manipulative Physiol Ther. 2012 Jul;35(6):437-45. [PMID:22902139]

Author information: Yu X, Wang X, Zhang J, Wang Y. Department of Physical Medicine and Rehabilitation, Renji Hospital, Jiaotong University, School of Medicine, Shanghai, China.

ClinicalTrials.gov Identifier: NCT01469533

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Evaluation of Mechanical Allodynia in an Animal Immobilization Model using the Von Frey Method

January 1, 2012 Activator IV, Animal Models, Neurophysiological, Research,

Abstract

OBJECTIVE:

The purpose of this study was to evaluate the mechanical allodynia in animals after immobilization and chiropractic manipulation using the Activator instrument (Activator Methods International, Phoenix, Ariz) through the Von Frey test in an animal model that had its hind limb immobilized as a form to induce mechanical allodynia.

METHOD:

Eighteen adult male Wistar rats were used and divided into 3 groups: control group (C) (n = 6) that was not immobilized; immobilized group (I) (n = 6) that had its right hind limb immobilized; immobilized and adjusted group (IAA) (n = 6) that had its right hind limb immobilized and received chiropractic manipulation after. The mechanical allodynia was induced through the right hind limb immobilization. At the end of the immobilization period, the first Von Frey test was performed, and after that, 6 chiropractic manipulations on the tibial tubercle were made using the Activator instrument. After the manipulation period, Von Frey test was performed again.

RESULTS:

It was observed that after the immobilization period, groups I and IAA had an exacerbation of mechanical allodynia when compared with group C (P < .001) and that after the manipulation, group IAA had a reversion of these values (P < .001), whereas group I kept a low pain threshold when compared with group C (P < .001).

CONCLUSION:

This study demonstrates that immobilization during 4 weeks was sufficient to promote mechanical allodynia. Considering the chiropractic manipulation using the Activator instrument, it was observed that group IAA had decreased levels of mechanical allodynia, obtaining similar values to group C.

J Manipulative Physiol Ther. 2012 Jan;35(1):18-25. [PMID:22054875]

Author information: Trierweiler J, Göttert DN, Gehlen G. Academic of Chiropractic from the University Feevale, Laboratory of Comparative Histophysiology, ICS, University Feevale, Novo Hamburgo, RS, Brazil.

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Cerebral Metabolic Changes in Men After Chiropractic Spinal Manipulation for Neck Pain

December 1, 2011 Neurophysiological, Research,

Abstract

BACKGROUND:

Chiropractic spinal manipulation (CSM) is an alternative treatment for back pain. The autonomic nervous system is often involved in spinal dysfunction. Although studies on the effects of CSM have been performed, no chiropractic study has examined regional cerebral metabolism using positron emission tomography (PET).

OBJECTIVE:

The aim of the present study was to investigate the effects of CSM on brain responses in terms of cerebral glucose metabolic changes measured by [18F] fluorodeoxyglucose positron emission tomography (FDG-PET).

METHODS:

Twelve male volunteers were recruited. Brain PET scanning was performed twice on each participant, at resting and after CSM. Questionnaires were used for subjective evaluations. A visual analogue scale (VAS) was rated by participants before and after chiropractic treatment, and muscle tone and salivary amylase were measured.

RESULTS:

Increased glucose metabolism was observed in the inferior prefrontal cortex, anterior cingulated cortex, and middle temporal gyrus, and decreased glucose metabolism was found in the cerebellar vermis and visual association cortex, in the treatment condition (P < .001). Comparisons of questionnaires indicated a lower stress level and better quality of life in the treatment condition. A significantly lower VAS was noted after CSM. Cervical muscle tone and salivary amylase were decreased after CSM. Conclusion The results of this study suggest that CSM affects regional cerebral glucose metabolism related to sympathetic relaxation and pain reduction.

Altern Ther Health Med. 2011 Nov-Dec;17(6):12-7. [PMID:22314714]

Author information: Ogura T, Tashiro M, Masud M, Watanuki S, Shibuya K, Yamaguchi K, Itoh M, Fukuda H, Yanai K. Division of Cyclotron Nuclear Medicine, Tohoku University, Sendai, Japan.

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