Archive for category Activator II

Abstract

OBJECTIVE:

To discuss a case involving a patient with chronic chest pain, dyspnea, and anxiety. Although resistant to previous treatment regimens, the condition responded favorably to chiropractic manipulation of the costosternal articulations.

CLINICAL FEATURES:

A 49-year-old man had chronic chest pain, dyspnea, and anxiety for over 4 months. The severity of the condition gradually progressed to the point of precluding the patient’s active employment and most physical activity. Prior efforts to treat the condition had met with failure.

INTERVENTION AND OUTCOME:

The patient received mechanical force, manually assisted short-lever chiropractic adjustment of the thoracic spine and, in particular, the costosternal articulations. Adjustments were by means of an Activator Adjusting Instrument II. The patient responded favorably to the intervention, obtaining prompt relief from his symptoms. Sustained chiropractic care rendered over a 14-week period resulted in complete resolution of the patient’s previously chronic condition, with recovery maintained at 9-month follow-up.

CONCLUSIONS:

Certain types of chest pain may have their etiology in a subluxation complex involving the costosternal articulation. Although the possibility of myocardial involvement must be considered with all patients whose symptoms include chest pain, a musculoskeletal involvement, including costosternal subluxation complex, may be the underlying cause of the symptoms in certain patients. When this is the case, chiropractic adjustment may provide an effective mode of treatment. Further study in an academic research venue is merited to investigate the role that conservative chiropractic care can provide for patients with chest pain.


J Manipulative Physiol Ther. 2003 Feb;26(2):108-15. [PMID:12584509]

Author information: Polkinghorn BS, Colloca CJ. Department Faculty, New York Chiropractic College, Seneca, New York, USA.

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Abstract

OBJECTIVE:

To describe a case of postsurgical neck pain, after multiple spinal surgeries, that was successfully treated by chiropractic intervention with instrumental adjustment of the cervical spine.

CLINICAL FEATURES:

A 35-year-old woman had chronic neck pain for over 5 years after two separate surgeries of the cervical spine: a diskectomy at C3/4 and a fusion at C5/6. Surgeries were performed 6 months apart in an attempt to resolve persistent neck pain and spasm of the cervical musculature. Neither surgery was effective in relieving the patient’s pain. Five years after the second surgery, a third surgery was recommended by the patient’s physicians to alleviate the chronic pain. The patient sought chiropractic evaluation of her condition to avoid further surgical intervention.

INTERVENTION AND OUTCOME:

The patient was treated with conservative instrumental chiropractic manipulation, consisting of mechanical force, manually assisted short-lever spinal adjustments rendered with an Activator Adjusting Instrument (AAI) II. She comfortably tolerated the treatment and responded favorably to this therapy. All chronic symptoms had resolved within 30 days of instituting the chiropractic instrumental adjustments with an AAI. More interestingly, longitudinal examination over the next 2 years showed that the patient experienced no residual effects or further recurrences of her previous chronic problem after her initial course of chiropractic care.

CONCLUSION:

Chiropractic treatment of postsurgical neck syndrome may be effectively treated, in certain cases, by mechanical force, manually assisted adjusting procedures with an AAI. The use of instrumental adjustment methodology may provide chiropractic physicians with an effective alternative to manual manipulation in those cases in which the patient’s surgical history or presenting symptoms make forceful manipulation of the spine, particularly performed at end range, inappropriate. This approach may be contemplated by physicians faced with managing this type of condition. Further study should be made in this regard, in an academic research setting, to determine the safest and most effective approaches to managing postsurgical patients in a chiropractic setting.


J Manipulative Physiol Ther. 2001 Nov-Dec;24(9):589-95. [PMID:11753333]

Author information: Polkinghorn BS, Colloca CJ. Private practice of chiropractic, Santa Monica, Calif., USA.

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Abstract BACKGROUND: Although the mechanisms of spinal manipulation are poorly understood, the clinical effects are thought to be related to mechanical, neurophysiologic, and reflexogenic processes. Animal studies have identified mechanosensitive afferents in animals, and clinical studies in human beings have measured neuromuscular responses to spinal manipulation. Few, if any, studies have identified the basic neurophysiologic […]

Fuhr Intraoperative

Abstract

BACKGROUND:

Although the mechanisms of spinal manipulation are poorly understood, the clinical effects are thought to be related to mechanical, neurophysiologic, and reflexogenic processes. Animal studies have identified mechanosensitive afferents in animals, and clinical studies in human beings have measured neuromuscular responses to spinal manipulation. Few, if any, studies have identified the basic neurophysiologic mechanisms of spinal manipulation in human beings or animals.

OBJECTIVES:

The purpose of this clinical investigation was to determine the feasibility of obtaining intraoperative neurophysiologic recordings and to quantify mixed-nerve root action potentials in response to lumbosacral spinal manipulation in a human subject undergoing lumbar spinal surgery.

METHODS:

An L4-L5 laminectomy was performed in a 62-year-old man. Short-duration (<0.1 ms) mechanical force, manually assisted spinal manipulative thrusts (150 N) were delivered to the lumbosacral spine with an Activator II Adjusting Instrument. With the spine exposed, spinal manipulative thrusts were delivered internally to the L5 mammillary process, L5-S1 joint, and the sacral base with various force vectors. This protocol was repeated by contacting the skin overlying respective anatomic landmarks. Mixed-nerve root recordings were obtained from gas-sterilized platinum bipolar hooked electrodes attached to the S1 nerve root at the level of the dorsal root ganglion during the spinal manipulative thrusts and during a 30-second baseline period during which no spinal manipulative thrusts were applied.

RESULTS:

During the active trials, mixed-nerve root action potentials were observed in response to both internal and external spinal manipulative thrusts. Differences in the amplitude and discharge frequency were noted in response to varying segmental contact points and force vectors, and similarities were noted for internally and externally applied spinal manipulative thrusts. Amplitudes of mixed-nerve root action potentials ranged from 200 to 2600 mV for internal thrusts and 800 to 3500 mV for external thrusts.

CONCLUSIONS:

Monitoring mixed-nerve root discharges in response to spinal manipulative thrusts in vivo in human subjects undergoing lumbar surgery is feasible. Neurophysiologic responses appeared sensitive to the contact point and applied force vector of the spinal manipulative thrust. Further study of the neurophysiologic mechanisms of spinal manipulation in humans and animals is needed to more precisely identify the mechanisms and neural pathways involved.


J Manipulative Physiol Ther. 2000 Sep;23(7):447-57. [PMID:11004648]

Author information: Colloca CJ, Keller TS, Gunzburg R, Vandeputte K, Fuhr AW. Postdoctoral and Related Professional Education Department Faculty, Logan College of Chiropractic, St. Louis, MO, USA.

 

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Abstract

STUDY DESIGN:

Surface electromyographic reflex responses associated with mechanical force, manually assisted (MFMA) spinal manipulative therapy were analyzed in this prospective clinical investigation of 20 consecutive patients with low back pain.

OBJECTIVES:

To characterize and determine the magnitude of electromyographic reflex responses in human paraspinal muscles during high loading rate mechanical force, manually assisted spinal manipulative therapy of the thoracolumbar spine and sacroiliac joints.

SUMMARY OF BACKGROUND DATA:

Spinal manipulative therapy has been investigated for its effectiveness in the treatment of patients with low back pain, but its physiologic mechanisms are not well understood. Noteworthy is the fact that spinal manipulative therapy has been demonstrated to produce consistent reflex responses in the back musculature; however, no study has examined the extent of reflex responses in patients with low back pain.

METHODS:

Twenty patients (10 male and 10 female, mean age 43.0 years) underwent standard physical examination on presentation to an outpatient chiropractic clinic. After repeated isometric trunk extension strength tests, short duration (<5 msec), localized posteroanterior manipulative thrusts were delivered to the sacroiliac joints, and L5, L4, L2, T12, and T8 spinous processes and transverse processes. Surface, linear-enveloped electromyographic (sEMG) recordings were obtained from electrodes located bilaterally over the L5 and L3 erector spinae musculature. Force-time and sEMG time histories were recorded simultaneously to quantify the association between spinal manipulative therapy mechanical and electromyographic response. A total of 1600 sEMG recordings were analyzed from 20 spinal manipulative therapy treatments, and comparisons were made between segmental level, segmental contact point (spinous vs. transverse processes), and magnitude of the reflex response (peak-peak [p-p] ratio and relative mean sEMG). Positive sEMG responses were defined as >2.5 p-p baseline sEMG output (>3.5% relative mean sEMG output). SEMG threshold was further assessed for correlation of patient self-reported pain and disability.

RESULTS:

Consistent, but relatively localized, reflex responses occurred in response to the localized, brief duration MFMA thrusts delivered to the thoracolumbar spine and SI joints. The time to peak tension (sEMG magnitude) ranged from 50 to 200 msec, and the reflex response times ranged from 2 to 4 msec, the latter consistent with intraspinal conduction times. Overall, the 20 treatments produced systematic and significantly different L5 and L3 sEMG responses, particularly for thrusts delivered to the lumbosacral spine. Thrusts applied over the transverse processes produced more positive sEMG responses (25.4%) in comparison with thrusts applied over the spinous processes (20.6%). Left side thrusts and right side thrusts over the transverse processes elicited positive contralateral L5 and L3 sEMG responses. When the data were examined across both treatment level and electrode site (L5 or L3, L or R), 95% of patients showed positive sEMG response to MFMA thrusts. Patients with frequent to constant low back pain symptoms tended to have a more marked sEMG response in comparison with patients with occasional to intermittent low back pain.

CONCLUSIONS:

This is the first study demonstrating neuromuscular reflex responses associated with MFMA spinal manipulative therapy in patients with low back pain. Noteworthy was the finding that such mechanical stimulation of both the paraspinal musculature (transverse processes) and spinous processes produced consistent, generally localized sEMG responses. Identification of neuromuscular characteristics, together with a comprehensive assessment of patient clinical status, may provide for clarification of the significance of spinal manipulative therapy in eliciting putative conservative therapeutic benefits in patients with pain of musculoskeletal origin.


 

Spine (Phila Pa 1976). 2001 May 15;26(10):1117-24. [PMID: 11413422]

Author information: Colloca CJ. Postdoctoral & Related Professional Education Department, Logan College of Chiropractic, St Louis, Missouri, USA.

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Abstract

BACKGROUND:

Previous studies have demonstrated the existence era reflex response, measurable by surface electromyography (sEMG), after manually delivered spinal manipulative therapy (SMT). This reflex response has been characterized as consistent, reproducible within individual subjects, and nonlocal because it extends beyond the site of manipulation. However, the nature and magnitude of possible reflex responses in the paraspinal and proximal limb muscles elicited by nonmanual SMT, such as with an adjusting instrument, remain unknown.

OBJECTIVE:

To characterize the reflex responses associated with SMT by using sEMG to record the responses of 16 muscles before, during, and after treatment.

STUDY DESIGN:

The eleetromyographic responses of 16 para-spinal and proximal limb muscles in 9 healthy, asymptomatic male volunteers were measured simultaneously by sEMG before, during, and after chiropractic SMT.

METHODS:

SMT thrusts were delivered to 9 asymptomatic volunteers at 6 bilateral sites (C3/4, T2/3, T6/8, T11/12, L2-4, and s1). Reflex responses were measured from 16 muscles with bipolar sEMG electrodes and collected at 2000 Hz per channel with data acquisition software.

RESULTS:

Approximately 68% of the SMT thrusts resulted in a detectable reflex response. The cervical spine resulted in a detectable response of 50%, thoracic spine 59%, lumbar spine 83%, and sacroiliac joints 94%. Treatments delivered to the thoracic spine elicited the largest peak-to-peak amplitude sEMG responses, whereas the lumbar spine demonstrated the most heterogeneous responses. When a reflex response was observed, it always occurred close to the treatment site ipsilaterally and was detected in muscles that had either their origin or insertion at the vertebral level that was adjusted.

CONCLUSIONS:

Based on the local nature, magnitude, and characteristic shape of all reflex responses observed, we hypothesized that they were likely generated by a single proprioceptor. Furthermore, the temporal properties of this reflex response suggest that they originated from the muscle spindles. In contrast to previous observations on reflex responses after manual SMT, these treatments elicited reflex responses that varied between subjects but were consistent within an individual and were local in nature. We conclude that SMT delivered in this manner results in a reflex response that is both quantitatively and qualitatively different from a manual SMT.


J Manipulative Physiol Ther. 2000 Mar-Apr;23(3):155-9. [PMID:10771499]

Author information: Symons BP, Herzog W, Leonard T, Nguyen H. Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.

 

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Abstract

OBJECTIVE:

To discuss a case of coccygodynia that responded favorably to conservative chiropractic adjusting procedures with the Activator Methods Chiropractic Technique (AMCT) and the Activator II Adjusting Instrument (AAI II).

CLINICAL FEATURES:

A 29-year-old woman had unremitting coccygeal pain of 3 weeks’ duration. The problem began after she had moved heavy boxes while at work. The pain was characterized by a continual dull ache in the coccygeal region, accompanied by intermittent sharp pain, particularly upon sitting or rising from a seated position. She had been taking self-prescribed over-the-counter analgesics (aspirin and ibuprofen) for 3 weeks without obtaining relief.

INTERVENTION AND OUTCOME:

Treatment consisted of mechanical force, manually assisted, short-lever (MFMA) chiropractic adjusting procedures to the coccygeal area, primarily the sacrococcygeal ligament. The AAI II was used to deliver the adjustment according to diagnostic and treatment protocol specified for AMCT. The patient experienced first treatment.

CONCLUSION:

Chiropractic coccygeal manipulation may be effectively delivered via instrumental adjustment in certain cases of coccygodynia. The use of an AAI II in administering the coccygeal adjustment has the benefit of being a gentle, noninvasive procedure, as well as being comfortably tolerated by the patient. This method of coccygeal adjustment may bear consideration in certain cases of coccygodynia.


J Manipulative Physiol Ther. 1999 Jul-Aug;22(6):411-6. [PMID:10478774]

Author information: Polkinghorn BS, Colloca CJ. Postdoctoral and Related Professional Education Department Faculty, Logan College of Chiropractic, Phoenix, Arizona, USA.

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Introduction:

Lumbar spinal disorders including radial  tears, disc degeneration, segmental instability and segmental  dysfunction have been considered common causes of persistent back pain  and sciatica. Such disorders may be characterized as exhibiting  alterations in the mechanical behavior to loading, notably, changes in  spinal stiffness. Studies investigating posteroanterior (PA) forces in  spinal stiffness assessment have shown relationships to spinal level,  body type, and lumbar extensor muscle activity. Such measures may be  important determinants to discriminate between patients with low back  pain and asymptomatic subjects. However, little objective evidence is  available discerning variations in PA stiffness, a more complete  assessment based upon dynamic stiffness measurements (driving-point  impedance) and concomitant neuromuscular response may offer more  information concerning mechanical properties of the low back, Thus, the  aim of the current study was to determine the stiffness and  neuromuscular characteristics of the asymptomatic and symptomatic low  back,

Methods:

This study is a prospective clinical study  investigating the mechanical and muscular behavior of lumbar spinal  segments to high loading rate PA forces, 22 subjects (12 male & 10  female, mean age of 42.8+ or – 17.5 years, range 15-73 years) underwent a  comprehensive physical examination consisting of history,  orthopedic/neurologic examination, lumbar range of motion, pressure  algometry and plain film radiographic exanimation of the lumbar spine. A  visual analog score (VAS), Oswestry Low Back Disability Index, and  Health Status Questionnaire (SF-36) were obtained for all subjects and  categorization was made on the basis of symptom frequency, as well as  positive vs. negative orthopedic exam, acute vs. chronic (>12 weeks)  low back pain (LBP) history and electromyography (EMG) response to PA  mechanical stimulation. Each subject was placed in the prone position by  use of a motorized vertical/horizontal table. Surface, linear  enveloped, EMG recordings were obtained from electrodes (8 lead s)  located over the L3 and L5 paraspinal musculature to monitor the  bilateral neuromuscular activity of the erector spinae group during the  PA stiffness measurement protocol, Prior to and immediately following  the PA mechanical stimulation, each subject performed three consecutive  maximal effort isometric trunk extensions to normalize EMG data. A  hand-held Activator II Adjusting Instrument equipped with a load cell  and accelerometer was used to deliver high rate (<0.1 msec ) PA  mechanical stimulation (450 N) to several common spinal landmarks  including the PSIS, sacral base and L5, L4, L2, T12, T8 spinous and  transverse processes. Driving point impedance (Z, Ns/m) was calculated  for each of the thrusts, from which the effective dynamic stiffness (Z x  2(3.21)f) was determined.

Results:

Two of the subjects were asymptomatic (no prior history of LBP), 6 had occasional LBP symptoms, 4 intermittent, and 10 had chronic symptoms of LBP. Subjects with chronic symptoms were characterized by higher effective dynamic stiffness at all levels and had a 2.5-fold higher Oswestry index and VAS score in comparison to the other subjects. Ten of the subjects had an abnormal orthopedic examination and were characterized by a significantly higher dynamic stiffness at all levels. These ten subjects also had over a 2.5-fold greater Oswestry index and VAS score in comparison to the subjects with a normal exam. LBP chronicity was also associated with a 2.5-fold and 3~fold greater Oswestry and VAS score, respectively, in comparison to acute pain sufferers. no differences in dynamic stiffness were observed between these subject groups, however. Of interest was our finding that 16 of the subjects exhibited a hyper-neuromuscular response in response to the PA mechanical stimulation. A hyper-neuromuscular response was characterized as a prominent EMG response (≥ 10% of the isometric extension EMG response) in 10% or more of the EMG recordings (80 total/subject). In this group of subjects the Oswestry index and VAS score were nearly 3-fold and 6-fold greater, respectively, in comparison to subjects which showed little or no mechanically-activated EMG response. Also noteworthy, was the finding that, while lumbar level PA stiffness measurements were similar for these two groups, the thoracic level PA stiffness values were significantly greater in the hyper-neuromuscular group.

Discussion:

The results of this preliminary study provide additional support for clinical assessment strategies that utilize a non-invasive dynamic stiffness measurement system to probe and quantify the mechanical characteristics of the spine. It was noted that subjects with hyper-neuromuscular responses presented with more severe disability outcome scores and a positive orthopedic exam. Further measurements of the dynamic stiffness and neuromuscular characteristics of the symptomatic and asymptomatic LBP population are required to clarify the significance of this observation. Such diagnostic measurements, when combined with conservative manipulative care of the back may prove to be a particularly effective means to diagnostically probe and treat lower back disorders.


Reference: Christopher J. Colloca, D.C., Tony S. Keller,  Ph.D. , Arlan W. Fuhr, D.C.; Muscular And Mechanical Behavior Of The  Lumbar Spine In Response To Dynamic Posteroanterior Forces; Proceedings  of the 26th Annual Meeting of the International Society for the Study of  the Lumbar Spine, Kona, Hawaii. Toronto: ISSLS, 1999: 136A.

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Abstract

OBJECTIVE:

To describe a case of symptomatic lumbar disc herniation, successfully treated via chiropractic intervention using Activator Methods Chiropractic Technique.

CLINICAL FEATURES:

A 26-yr-old man suffered from a chronic multisymptom complex composed of low back pain, left groin pain, left leg pain, left foot drop and associated muscle weakness with atrophy. The symptoms had persisted for more than 2 yr after an athletic injury. Magnetic resonance imaging evaluation revealed a 6-mm focal central disc protrusion with accompanying deformation of the thecal sac, consistent with the presenting symptoms. Lumbar spinal surgery had been recommended to the patient as the appropriate medical management for optimal outcome.

INTERVENTION AND OUTCOME:

The patient elected to pursue chiropractic treatment in an effort to resolve his condition via conservative management. Chiropractic intervention consisted of mechanical-force, manually assisted short-lever adjusting procedures, rendered via an Activator Adjusting Instrument (AAI). The patient responded favorably and his multisymptom complex resolved within 90 days of treatment. No residuals or recurrences were noted at examination over 1 yr later.

CONCLUSION:

This report suggests that chiropractic treatment of lumbar disc disorders may be effectively implemented, in certain cases, via mechanical-force, manually assisted adjusting procedures using an AAI. We speculate that the use of an AAI, combined with Activator methods, may provide definitive benefits over side-posture manipulation of the lumbar spine in treatment of resistive disc lesions, because of the lack of torsional stress imposed upon the disc during instrumental spinal adjustment. Further study should be made in this regard to determine the safest and most effective method to treat lumbar disc lesions in a chiropractic setting.


J Manipulative Physiol Ther. 1998 Mar-Apr;21(3):187-96. [PMID:9567239]

Author information: Polkinghorn BS, Colloca CJ. Private practice of chiropractic, Santa Monica, CA, USA.

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