Archive for category Research

Beneficial Effects of Manually Assisted Chiropractic Adjusting Instrument in a Rabbit Model of Osteoarthritis

October 1, 2021 Activator V, Animal Models, Osteoperosis, Research,

Abstract

OBJECTIVE:

Osteoarthritis (OA) is a degenerative disease characterized by injury of all joint tissues. Our previous study showed that in experimental osteoporosis, chiropractic manipulation (CM) exerts protective effects on bone. We here assessed whether CM might ameliorate OA by improving subchondral bone sclerosis, cartilage integrity, and synovitis.

METHODS:

Male New-Zealand rabbits underwent knee surgery to induce OA by anterior cruciate ligament injury. CM was performed using the chiropractic instrument ActivatorV 3 times/week for 8 weeks as follows: force 2 setting was applied to the tibial tubercle of the rabbit right hind limb (TM-OA), whereas the corresponding left hind limb received a false manipulation (FM-OA) consisting of ActivatorV firing in the air and slightly touching the tibial tubercle.

RESULTS:

After sacrifice, subchondral bone integrity was assessed in the tibiae by microCT and histology. Cartilage damage and synovitis were estimated by Mankin’s and Krenn’s scores, respectively, and histological techniques. Bone mineral density and content in both cortical and trabecular compartments of subchondral bone decreased in OA rabbits compared to controls but partially reversed in the TM-OA group. Trabecular bone parameters in the latter group also showed a significant improvement compared to the FM-OA group. Moreover, RANKL, OPG, ALP, and TRAP protein expression in subchondral bone significantly decreased in TM-OA rabbits with respect to the FM-OA group. CM was associated with lower Mankin’s and Krenn’s scores and macrophage infiltrate together with a decreased protein expression of pro-inflammatory, fibrotic, and angiogenic factors, in TM-OA rabbits with respect to FM-OA.

CONCLUSIONS:

Our results suggest that CM may mitigate OA progression by improving subchondral bone as well as cartilage and synovial membrane status.

Scientific Reports volume 10, Article number: 13237 (2020) Cite this article

Author information: F. M. Conesa-Buendía, A. Mediero, R. Fujikawa, P. Esbrit, F. Mulero, I. Mahillo-Fernández & Arantxa Ortega-De Mues

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Determining spinal level using the inferior angle of the scapula as a reference landmark: a retrospective analysis of 50 radiographs

November 20, 2018 Biomechanical, Research,

Abstract

OBJECTIVE:

The purpose of this study was to determine which spinal segment most closely corresponds to the level of the inferior angle of the scapula (IAS) using measurements taken on A-P full-spine radiographs.

METHODS:

Fifty sequentially selected radiographs were analyzed independently by two examiners. A straight edge was used to ascertain which spinal levels corresponded with the right and left IASs. For analysis, each spinal level was subdivided into three regions: the upper vertebral body, lower vertebral body, and intervertebral space.

RESULTS:

The mean spinal level corresponding to the left IAS was midway between the T8–9 interspace and the upper T9 body (range, lower T7 to upper T10). The mean spinal level corresponding to the right IAS was slightly lower, but still within the upper T9 body (range, lower T7 to lower T10). These levels correspond to the T8 spinous process.

CONCLUSIONS:

There is a considerable amount of variability in where the IASs are located, but most commonly, they correspond to the level of the upper body of T9.

. 2008 Mar; 52(1): 24–29. PMID: 18327299

Author information: Michael T. Haneline, MPH, DC,* Robert Cooperstein, MA, DC, Morgan D. Young, BS, and Justin Ross, RN, DC

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A Prospective, Randomized, Double Blind, Placebo Controlled Clinical Trial Assessing the Effects of Applying a Force to C5 by a Mechanically Assisted Instrument (MAI) on Referred Pain to the Shoulder

April 1, 2018 Clinical Trials, Research,

Abstract

Objective:

To determine the effects of applying a force to C5 of the spine by a mechanically assisted instrument (MAI) in patients with referred shoulder pain.

Summary of Background Data:

Manipulating C5 of the spine is a chiropractic treatment for referred shoulder pain, there are no clinical trials evaluating its efficacy. Outcome measures were patient ranked questionnaires and independent examiner findings. One hundred and twenty-five patients were diagnosed with referred shoulder pain of cervical origin; sixty-five were in the treatment cohort and sixty in the placebo cohort.

Methods:

This was a prospective, randomized, double-blind, placebo-controlled trial assessing the effects of applying a force to C5 by an MAI to patients with referred shoulder pain. The treatment cohort had the MAI set at the maximum setting to transmit a force into the spine; the placebo cohort had the MAI turned off. Primary outcome measures were frequency and severity of extreme shoulder pain obtained via a patient-reported questionnaire; secondary outcome measures were patient ranked pain and functional outcomes, as well as the examiner, assessed the range of motion and strength. Assessment procedures were completed at 24 weeks post-treatment and data were analyzed with intent to treat protocol.

Results:

There was a reduction in the frequency but not the severity of extreme shoulder pain in the treatment cohort, average ranking reducing from weekly to monthly (p < 0.05). Patients treated with the MAI had 10 N (p = 0.04) better internal rotation strength after 6 months post-treatment. No differences with any other outcome measures between the two cohorts at the 24 week study period.

Conclusion:

The major effect of applying an MAI to the level of C5 of the spine in referred shoulder pain is improved shoulder strength for internal rotation in this randomized double-blinded clinical trial.

Spine (Phila Pa 1976). 2017 Sep 6.  PMID: 28885296
Author information: Hardas GM, Murrell GA. Orthopaedic Research Institute, St George Hospital Clinical School, Faculty of Medicine, UNSW, Sydney, Australia.

Epub ahead of print

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Characteristics of Paraspinal Muscle Spindle Response to Mechanically Assisted Spinal Manipulation: A Preliminary Report

June 17, 2017 Activator V, Animal Models, Research,

Abstract

Objective:

The purpose of this preliminary study is to determine muscle spindle response characteristics related to the use of 2 solenoid powered clinical mechanically assisted manipulation (MAM) devices.

Methods:

L6 muscle spindle afferents with receptive fields in paraspinal muscles were isolated in 6 cats. Neural recordings were made during L7 MAMthrusts using the Activator V (Activator Methods Int. Ltd., Phoenix, AZ) and/or Pulstar (Sense Technology Inc., Pittsburgh, PA) devices at their 3 lowest force settings. Mechanically assisted manipulation response measures included (a) the time required post-thrust until the first action potential, (b) differences in mean frequency (MF) and mean instantaneous frequency (MIF) 2 seconds before and after MAM, and (c) the time required for muscle spindle discharge (MF and MIF) to return to 95% of baseline after MAM.

Results:

Depending on device setting, between 44% to 80% (Pulstar) and 11% to 63% (Activator V) of spindle afferents required N6 seconds to return to within 95% of baseline MF values; whereas 66% to 89% (Pulstar) and 75% to 100% (Activator V) of spindle responses returned to within 95% of baseline MIF in b6 seconds after MAM. Nonparametric comparisons between the 22N and 44N settings of the Pulstar yielded significant differences for the time required to return to baseline MF and MIF.

Conclusion:

Short duration (b10 ms) MAM thrusts decrease muscle spindle discharge with a majority of afferents requiring prolonged periods (N6 seconds) to return to baseline MF activity. Physiological consequences and clinical relevance of described MAM mechanoreceptor responses will require additional investigation.

J Manipulative Physiol Ther. 2017 Jun 17. PMID: 28633885
Author information: William R. Reed, DC, PhD, Joel G. Pickar, DC, PhD, Randall S. Sozio, BS, LATG, Michael A.K. Liebschner, PhD,  Joshua W. Little, DC, PhD, and Maruti R. Gudavalli, PhD. Palmer Center for Chiropractic Research, Palmer College of Chiropractic, Davenport, IA.

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Clinical Trials

April 15, 2016 Clinical Trials, Research,

Published Clinical Trials Using the Activator Adjusting Instrument (AAI)

The Activator Method is one of the most widely researched chiropractic techniques and the only instrument adjusting technique with clinical trials to support its efficacy. The following list of clinical trials demonstrate that there is sufficient published evidence that use of the Activator adjusting instrument results in therapeutic benefits equivalent to manual-thrust and/or diversified chiropractic manipulation.

  1. Effects of chiropractic treatment on blood pressure and anxiety: a randomized, controlled trial. Yates RG, Lamping DL, Abram NL, Wright C. J Manipulative Physiol Ther. 1988 Dec;11(6):484-8.

Main Results/Conclusions: Systolic and diastolic blood pressure decreased significantly in the active treatment condition. No significant changes occurred in the placebo and control conditions. Anxiety significantly decreased in the active and control conditions.

  1. Treatment and biomechanical assessment of patients with chronic sacroiliac joint syndrome. Osterbauer PJ, De Boer KF, Widmaier R, Petermann E, Fuhr AW. J Manipulative Physiol Ther. 1993 Feb;16(2):82-90.

Main Results/Conclusions: Activator proved beneficial in treatment of chronic Sacro-Iliac Joint Syndrome (SIJS); average Oswestry Disability Index (ODI) scores diminished from 28 to 13%.

  1. The immediate effect of activator vs. meric adjustment on acute low back pain: a randomized controlled trial. Gemmell HA, Jacobson BH. J Manipulative Physiol Ther. 1995 Sep;18(7):453-6.

Main Results/Conclusions: Both interventions showed improvement in all outcome measures, but no statistical significance between groups.

  1. Comparison of two chiropractic techniques on pain and lateral flexion in neck pain patients: a pilot study. Yurkiw D, Mior S. Chiropractic Technique. 1996 Nov;8(4):155-162.

Main Results/Conclusions: No statistical significance between interventions. Both interventions showed immediate improvement in all outcome measures.

  1. The effects of spinal manipulation on the intensity of emotional arousal in phobic subjects exposed to a threat stimulus: a randomized, controlled, double-blind clinical trial. Peterson KB. J Manipulative Physiol Ther. 1997 Nov-Dec;20(9):602-6.

Main Results/Conclusions: Activator-assisted spinal manipulation significantly decreased the intensity of emotional arousal reported by phobic subjects.

  1. A pilot randomized clinical trial on the relative effect of instrumental (MFMA) versus manual (HVLA) manipulation in the treatment of cervical spine dysfunction. Wood TG, Colloca CJ, Matthews R. J Manipulative Physiol Ther. 2001 May;24(4):260-71.

Main Results/Conclusions: No statistical significance between interventions. Both Activator and manual manipulation showed beneficial effects in reducing pain and disability while increasing range of motion.

  1. Chiropractic treatment of temporomandibular disorders using the activator adjusting instrument: a prospective case series. DeVocht JW, Long CR, Zeitler DL, Schaeffer W. J Manipulative Physiol Ther. 2003 Sep;26(7):421-5.

Main Results/Conclusions: Signs and symptoms of temporomandibular disorders improved with the course of Activator Methods treatment.

  1. A randomized clinical trial of manual versus mechanical force manipulation in the treatment of sacroiliac joint syndrome. Shearar KA, Colloca CJ, White HL. J Manipulative Physiol Ther. 2005 Sep;28(7):493-501.

Main Results/Conclusions: No statistical significance between interventions. Both interventions showed immediate improvement in all outcome measures.

  1. Immediate effect of activator trigger point therapy and myofascial band therapy on non-specific neck pain in patients with upper trapezius trigger points compared to sham ultrasound: A randomised controlled trial. Blikstad A, Gemmell H. Clinical Chiropractic (2008) 11, 23—29.

Main Results/Conclusions: Activator trigger point therapy appeared to be more effective than myofascial band therapy or sham ultrasound in treating patients with non-specific neck pain and upper trapezius trigger points.

  1. Relative immediate effect of ischaemic compression and activator trigger point therapy on active upper trapezius trigger points: A randomised trial. Gemmell H, Allen A. Clinical Chiropractic (2008) 11,175—181.

Main Results/Conclusions: Both interventions showed improvement in all outcome measures, but no statistical significance between groups

  1. Effects of a manually assisted mechanical force on cutaneous temperature. Roy RA, Boucher JP, Comtois AS. J Manipulative Physiol Ther. 2008 Mar;31(3):230-6.

Main Results/Conclusions: Before treatment, the cutaneous temperature (CT) was significantly different between the ipsilateral and the contralateral sides for all subgroups consistent with a positive L4/L5 isolation test. At 10 minutes after intervention, CT increased significantly for the treatment group but not for the sham and control groups. Furthermore, after manipulation using the Activator with a thrust respecting the standard loading principle of the instrument, it produced a secondary cooling at 5 minutes followed by a rewarming at 10 minutes consistent with a neurophysiological response.

  1. Heart rate variability modulation after manipulation in pain-free patients vs patients in pain. Roy RA, Boucher JP, Comtois AS. J Manipulative Physiol Ther. 2009 May;32(4):277-86.

Main Results/Conclusions: No statistical significance between interventions except for control group. Both interventions showed similar modulation of the HRV.

  1. Relative effectiveness and adverse effects of cervical manipulation, mobilisation and the activator instrument in patients with sub-acute non-specific neck pain: results from a stopped randomised trial. Gemmell H, Miller P. Chiropr Osteopat. 2010 Jul 9;18:20.

Main Results/Conclusions: There were no significant differences between the groups at any of the follow up points. All groups exhibited long-term improvement without one being superior to the other.

  1. Mechanical vs manual manipulation for low back pain: an observational cohort study. Schneider MJ, Brach J, Irrgang JJ, Abbott KV, Wisniewski SR, Delitto A. J Manipulative Physiol Ther. 2010 Mar-Apr;33(3):193-200.

Main Results/Conclusions: This study found neither intervention superior to the other, while providing the chiropractic profession with valuable information on the influence of treatment expectation.

  1. Inflammatory response following a short-term course of chiropractic treatment in subjects with and without chronic low back pain. Roy RA, Boucher JP, Comtois AS. J Chiropr Med. 2010 Sep;9(3):107-14.

Main Results/Conclusions: A total of 9 chiropractic lower back manipulations with the Activator caused the mediators of inflammation to present a normalization response in individuals suffering from chronic low back pain.

  1. Changes in Pressure Pain Thresholds and Basal Electromyographic Activity After Instrument-Assisted Spinal Manipulative Therapy in Asymptomatic Participants: A Randomized, Controlled Trial. Yu X, Wang X, Zhang J, Wang Y. J Manipulative Physiol Ther. 2012 Jul;35(6):437-45.

Main Results/Conclusions: The application of Activator instrument resulted in an immediate and widespread hypoalgesic effect with local muscle relaxation in asymptomatic participants.

  1. Comparison of paraspinal cutaneous temperature measurements between subjects with and without chronic low back pain. Roy RA, Boucher JP, Comtois AS. J Manipulative Physiol Ther. 2013 Jan;36(1):44-50.

Main Results/Conclusions: The Paraspinal Cutaneous Temperature (PCT) readings for subjects with chronic low back pain were lower than the asymptomatic, nontreatment group. The PCT temperature of the treatment group normalized after nine (9) treatments.

  1. A pilot study of a chiropractic intervention for management of chronic myofacial TMD. DeVocht JW, Goertz CM, Hondras MA, Long CR, Schaeffer W, Thomann L, Spector M, Stanford CM. J Am Dent Assoc. 2013 Oct;144(10).

Main Results/Conclusions: 721 potential participants were screened, 80 enrolled, and 53 completed the 6 month assessment. In the end, the logistics were found to be manageable. NOTE: This pilot study was funded by a NCCAM TMD study grant (2008) and was a necessary step in preparation for a larger Randomized Control Trial that will provide clinicians with information helpful when discussing treatment options for those who suffer with TMD.

  1. Comparison of Spinal Manipulation Methods and Usual Medical Care for Acute and Subacute Low Back Pain: A Randomized Clinical Trial. Schneider M, Haas M, Glick R, Stevans J, Landsittel D. Spine 2015;40:209-217.

Main Results/Conclusions: This study found that manual-thrust manipulation (MTM) provided slightly greater short-term (at 4 weeks) reductions in self-reported disability and pain scores compared with mechanical-assisted manipulation (Activator) or usual medical care (UMC); Activator was more effective for pain reduction than usual medical care in the first two-weeks. In addition, the benefit of MTM seen at end-of-intervention was no longer statistically significant at 3 or 6 months. All interventions seem similar in effect; they lead to decreased pain and disability.

  1. A Randomized Controlled Trial to Measure the Effects of Specific Thoracic Chiropractic Adjustments on Blood Pressure and Pulse Rate. Roffers SD, Menke JM, Morris DH. Asian Journal of Multidisciplinary Studies, Volume 3, Issue 6, June 2015.

Main Results/Conclusions: Specific thoracic spinal manipulations affected three measures: blood pressure, pulse rate, and changes in hypertension classification only in the active treatment group. Activator instrument’s utility for sham settings was supported for future efficacy studies.

  1. Comparing Outcome Measures in Lumbar Spine Manipulations: Dynamic X-Rays and Oswestry Index.Roy RA, Bouchera JP, Comtois AS. Spine Research, Spine Research. 2016 Vol. 2 No. 1: 12 (iMedPub Journal)

Main Results/Conclusions: Dynamic radiographs and the Oswestry index appear to be sensitive enough to detect a strong effect size after a 9-treatment course of therapy. In addition, a significant correlation was found between pre- and post-treatment measurements of the Oswestry index and dynamic radiographs which could help validate the necessity of continued care.

  1. Manual and Instrument Applied Cervical Manipulation for Mechanical Neck Pain: A Randomized Controlled Trial. Gorrell LM, Beath K, Engel RM. J Manipulative Physiol Ther. 2016 Jun;39(5):319-29.

Main Results/Conclusions: This study demonstrates that a single cervical manipulation is capable of producing both immediate and short-term benefits for mechanical neck pain. The study also may demonstrate that not all manipulative techniques have the same effect. The results reported in this study are consistent with the hypothesis that the biomechanical characteristics of different spinal manipulation techniques may be responsible for varying clinical effects. However, the results are not definitive, and further research investigating the nature of these changes is warranted.

  1. A Prospective, Randomized, Double Blind, Placebo Controlled Clinical Trial Assessing the Effects of Applying a Force to C5 by a Mechanically Assisted Instrument (MAI) on Referred Pain to the Shoulder.  Hardas GM, Murrell GA. Spine (Phila Pa 1976). 2017 Sep 6.

Main Results/Conclusions: The major effect of applying an MAI to the level of C5 of the spine in referred shoulder pain is improved shoulder strength for internal rotation in this randomized double-blinded clinical trial.

Systematic Review

The following systematic review of the literature demonstrates that there is sufficient published evidence that use of the Activator adjusting instrument results in therapeutic benefits equivalent to manual-thrust and/or diversified chiropractic manipulation.

Clinical effectiveness of the activator adjusting instrument in the management of musculo-skeletal disorders: a systematic review of the literature. Huggins T, Boras AL, Gleberzon BJ, Popescu M, Bahry LA. J Can Chiropr Assoc. 2012 Mar;56(1):49-57.

Main Results/Conclusions: “This systematic review of 8 clinical trials involving the use of the AAI (Activator) found reported benefits to patients with spinal pain and trigger points, although these results were not statistically significantly different when compared to the use of HVLA manual manipulation or trigger point therapy.”

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Attenuation Effect of Spinal Manipulation on Neuropathic and Postoperative Pain Through Activating Endogenous Anti-Inflammatory Cytokine Interleukin 10 in Rat Spinal Cord

January 11, 2016 Activator IV, Animal Models, Inflammation, Research,

Abstract

OBJECTIVES:

The purpose of this study was to investigate roles of the anti-inflammatory cytokine interleukin (IL) 10 and the proinflammatory cytokines IL-1β and tumor necrosis factor α (TNF-α) in spinal manipulation-induced analgesic effects of neuropathic and postoperative pain.

METHODS:

Neuropathic and postoperative pain were mimicked by chronic compression of dorsal root ganglion (DRG) (CCD) and decompression (de-CCD) in adult, male, Sprague-Dawley rats. Behavioral pain after CCD and de-CCD was determined by the increased thermal and mechanical hypersensitivity of the affected hindpaw. Hematoxylin and eosin staining, whole-cell patch clamp electrophysiological recordings, immunohistochemistry, and enzyme-linked immunosorbent assay were used to examine the neural inflammation, neural excitability, and expression of c-Fos and PKC as well as levels of IL-1β, TNF-α, and IL-10 in blood plasma, DRG, or the spinal cord. We used the activator adjusting instrument, a chiropractic spinal manipulative therapy tool, to deliver force to the spinous processes of L5 and L6.

RESULTS:

After CCD and de-CCD treatments, the animals exhibited behavioral and neurochemical signs of neuropathic pain manifested as mechanical allodynia and thermal hyperalgesia, DRG inflammation, DRG neuron hyperexcitability, induction of c-Fos, and the increased expression of PKCγ in the spinal cord as well as increased level of IL-1β and TNF-α in DRG and the spinal cord. Repetitive Activator-assisted spinal manipulative therapy significantly reduced simulated neuropathic and postoperative pain, inhibited or reversed the neurochemical alterations, and increased the anti-inflammatory IL-10 in the spinal cord.

CONCLUSION:

These findings show that spinal manipulation may activate the endogenous anti-inflammatory cytokine IL-10 in the spinal cord and thus has the potential to alleviate neuropathic and postoperative pain.

J Manipulative Physiol Ther. 2016 Jan;39(1):42-53. [PMID:26837229]

Author information: Song XJ, Huang ZJ, Song WB, Song XS, Fuhr AF, Rosner AL, Ndtan H, Rupert R5. Parker University, Parker Research Institute, Dallas, TX.

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A Randomized Controlled Trial to Measure the Effects of Specific Thoracic Chiropractic Adjustments on Blood Pressure and Pulse Rate

June 1, 2015 Activator IV, Clinical Trials, Hypertension Blood Pressure, Research,

Abstract

OBJECTIVE:

A randomized controlled trial (RCT) was designed to test effects of specific thoracic (T1 to T5) manipulations using an Activator instrument for changes in diastolic and systolic blood pressure, blood pressure classification, and pulse rates in 290 normotensive and hypertensive people in El Salvador.

METHODS:

Informed consent was obtained from 290 subjects meeting the inclusion criteria. They were randomly assigned to one of three groups: Control (i.e., no treatment, N=95); Placebo treatment (N=96); or Active treatment (N=99). Subjects’ blood pressure and pulse rates were measured after relaxing for 15 minutes, then before intervention, and again just after treatment.

RESULTS:

Systolic and diastolic BP, pulse rate, and BP classification decreased significantly only in the active treatment group. No significant changes occurred in the placebo treatment and control groups. Activator treatment’s effect size in changing hypertension classification as compared to no treatment was a medium d = 0.37, and 0.45 when compared to placebo.

CONCLUSION:

Specific thoracic spinal manipulations affected three measures: blood pressure, pulse rate, and changes in hypertension classification only in the active treatment group. Findings may represent in part a rebound effect from treatment anxiety, but this alone did not account for the observations. Activator instrument’s utility for sham settings was supported for future efficacy studies. The decrease was robust across several analyses, but the duration of the effect requires longer-term follow up.

Asian Journal of Multidisciplinary Studies, Vol 3, No 6, (June, 2015).

Author information: Roffers SD, Menke JM, Morris DH. Chiropractic Research Alliance, 1046 Davis Circle NW, Atlanta, GA 30318, U.S.A.

ClinicalTrials.gov Identifier: NCT01591967

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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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Comparison of spinal manipulation methods and usual medical care for acute and subacute low back pain: a randomized clinical trial.

February 1, 2015 Activator IV, Clinical Trials, Research,

Abstract

STUDY DESIGN:

Randomized controlled trial with follow-up to 6 months.

OBJECTIVE:

This was a comparative effectiveness trial of manual-thrust manipulation (MTM) versus mechanical-assisted manipulation (MAM); and manipulation versus usual medical care (UMC).

SUMMARY OF BACKGROUND DATA:

Low back pain (LBP) is one of the most common conditions seen in primary care and physical medicine practice. MTM is a common treatment for LBP. Claims that MAM is an effective alternative to MTM have yet to be substantiated. There is also question about the effectiveness of manipulation in acute and subacute LBP compared with UMC.

METHODS:

A total of 107 adults with onset of LBP within the past 12 weeks were randomized to 1 of 3 treatment groups: MTM, MAM, or UMC. Outcome measures included the Oswestry LBP Disability Index (0-100 scale) and numeric pain rating (0-10 scale). Participants in the manipulation groups were treated twice weekly during 4 weeks; subjects in UMC were seen for 3 visits during this time. Outcome measures were captured at baseline, 4 weeks, 3 months, and 6 months.

RESULTS:

Linear regression showed a statistically significant advantage of MTM at 4 weeks compared with MAM (disability = -8.1, P = 0.009; pain = -1.4, P = 0.002) and UMC (disability = -6.5, P = 0.032; pain = -1.7, P < 0.001). Responder analysis, defined as 30% and 50% reductions in Oswestry LBP Disability Index scores revealed a significantly greater proportion of responders at 4 weeks in MTM (76%; 50%) compared with MAM (50%; 16%) and UMC (48%; 39%). Similar between-group results were found for pain: MTM (94%; 76%); MAM (69%; 47%); and UMC (56%; 41%). No statistically significant group differences were found between MAM and UMC, and for any comparison at 3 or 6 months.

Spine (Phila Pa 1976). 2015 Feb 15;40(4):209-17. [PMID:25423308]

Author information: Schneider M, Haas M, Glick R, Stevans J, Landsittel D. School of Health and Rehabilitation Sciences, Clinical and Translational Science Institute, University of Pittsburgh, Pittsburgh, PA.

Full Text Article

ClinicalTrials.gov Identifier: NCT01211613

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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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