John J. Triano

Correlation of objective measure of trunk motion and muscle function with low back disability ratings

A study was undertaken to examine relations among some objective and subjective measures of low-back-related disability in a group of 41 low-back pain patients and in seven pain-free control subjects. Subjective measures of disability were obtained by Oswestry patient questionnaires. Oswestry disability score related significantly (P <0.001) to presence or absence of relaxation in back muscles during flexion. Mean trunk strength ratios were inversely related to disability score (P <.05), and trunk mobility was meaningfully reduced (P <.01). Despite loss of motion, a large enough excursion was observed to predict presence of back muscle relaxation. These findings imply that myoelectric signal levels, trunk strength ratios, and ranges of trunk motion may be used as objective indicators of low-back pain disability.

Loads transmitted during lumbosacral spinal manipulative therapy

Study Design. An in vivo biomechanical study of three separate manipulation procedures administered in random order. A biomechanical computer model estimated the loads passing through the spine at the level of interest. Objectives. The difference in loading effects from manipulation were contrasted for all six degrees of freedom based on treatment method. Quantitative information was compared with loads predicted by existing biomechanical models for work tasks in materials handling jobs. Summary of Background Data. Benefits to patients with low back pain from manipulation have been reported. Little is known about the biomechanics for any of the several types of procedures available or about how the loads that are applied affect the spine. Studies of isolated forces applied during high‐velocity and low‐amplitude procedures in constrained conditions have been made. Values have ranged from 20 N to 550 N at rates up to 7101 N/sec. Vertebral motions arising from these forces have been estimated to be up to 0.1 cm and 1.8 degrees. Complex loads that pass from common lumbar procedures through the spine have not been studied. Methods. A total of 54 samples from procedures were administered in random order to 11 volunteers. The amplitude of loads was controlled, by intent of the procedure, to be as large as deemed clinically safe. Volunteers were positioned on a specially constructed treatment table capable of sensing forces and moments about three axes. Myoelectric measures of trunk muscles were obtained by surface electrode recordings. Measurements served as input to a biomechanical model that estimated the loads passing through the spine during the procedures. Statistical descriptions of the procedures and their component loads were constructed, and comparisons were made based on the high‐velocity and low‐amplitude procedure applied and variation in the volunteers initial posture. Values were contrasted with spinal loads during materials handling activities. Results. Validity and fidelity of the table reaction loads were confirmed. Muscular response during the procedures was negligible and did not enter into the estimates of loads transmitted through the spine. Statistical significance (0.000 < P < 0.180) was found for comparisons of transmitted load components based on high‐velocity and low‐amplitude procedures and initial posture. Effects on the spine were comparable with those encountered by airline baggage handlers, with 92% of men and 83% of women estimated to be of sufficient strength to sustain them. None of the volunteers experienced any discomfort or complications as a result of the tests. Conclusion. The data reported here support the hypothesis that transmitted loads may be influenced by patient posture and the procedure selected. These loads, however, were more complex than clinically assumed. Estimates of the loads transmitted were consistent with those observed in common tasks requiring lifting and twisting movements.

Reduced thoracolumbar fascia shear strain in human chronic low back pain

BackgroundThe role played by the thoracolumbar fascia in chronic low back pain (LBP) is poorly understood. The thoracolumbar fascia is composed of dense connective tissue layers separated by layers of loose connective tissue that normally allow the dense layers to glide past one another during trunk motion. The goal of this study was to quantify shear plane motion within the thoracolumbar fascia using ultrasound elasticity imaging in human subjects with and without chronic low back pain (LBP).MethodsWe tested 121 human subjects, 50 without LBP and 71 with LBP of greater than 12 months duration. In each subject, an ultrasound cine-recording was acquired on the right and left sides of the back during passive trunk flexion using a motorized articulated table with the hinge point of the table at L4-5 and the ultrasound probe located longitudinally 2 cm lateral to the midline at the level of the L2-3 interspace. Tissue displacement within the thoracolumbar fascia was calculated using cross correlation techniques and shear strain was derived from this displacement data. Additional measures included standard range of motion and physical performance evaluations as well as ultrasound measurement of perimuscular connective tissue thickness and echogenicity.ResultsThoracolumbar fascia shear strain was reduced in the LBP group compared with the No-LBP group (56.4% ± 3.1% vs. 70.2% ± 3.6% respectively, p < .01). There was no evidence that this difference was sex-specific (group by sex interaction p = .09), although overall, males had significantly lower shear strain than females (p = .02). Significant correlations were found in male subjects between thoracolumbar fascia shear strain and the following variables: perimuscular connective tissue thickness (r = -0.45, p <.001), echogenicity (r = -0.28, p < .05), trunk flexion range of motion (r = 0.36, p < .01), trunk extension range of motion (r = 0.41, p < .01), repeated forward bend task duration (r = -0.54, p < .0001) and repeated sit-to-stand task duration (r = -0.45, p < .001).ConclusionThoracolumbar fascia shear strain was ~20% lower in human subjects with chronic low back pain. This reduction of shear plane motion may be due to abnormal trunk movement patterns and/or intrinsic connective tissue pathology. There appears to be some sex-related differences in thoracolumbar fascia shear strain that may also play a role in altered connective tissue function.

Chiropractic as spine care: a model for the profession

BackgroundMore than 100 years after its inception the chiropractic profession has failed to define itself in a way that is understandable, credible and scientifically coherent. This failure has prevented the profession from establishing its cultural authority over any specific domain of health care.ObjectiveTo present a model for the chiropractic profession to establish cultural authority and increase market share of the public seeking chiropractic care.DiscussionThe continued failure by the chiropractic profession to remedy this state of affairs will pose a distinct threat to the future viability of the profession. Three specific characteristics of the profession are identified as impediments to the creation of a credible definition of chiropractic: Departures from accepted standards of professional ethics; reliance upon obsolete principles of chiropractic philosophy; and the promotion of chiropractors as primary care providers. A chiropractic professional identity should be based on spinal care as the defining clinical purpose of chiropractic, chiropractic as an integrated part of the healthcare mainstream, the rigorous implementation of accepted standards of professional ethics, chiropractors as portal-of-entry providers, the acceptance and promotion of evidence-based health care, and a conservative clinical approach.ConclusionThis paper presents the spine care model as a means of developing chiropractic cultural authority and relevancy. The model is based on principles that would help integrate chiropractic care into the mainstream delivery system while still retaining self-identity for the profession.

Chiropractic management of low back pain and low back-related leg complaints: a literature synthesis.

OBJECTIVES The purpose of this project was to review the literature for the use of spinal manipulation for low back pain (LBP). METHODS A search strategy modified from the Cochrane Collaboration review for LBP was conducted through the following databases: PubMed, Mantis, and the Cochrane Database. Invitations to submit relevant articles were extended to the profession via widely distributed professional news and association media. The Scientific Commission of the Council on Chiropractic Guidelines and Practice Parameters (CCGPP) was charged with developing literature syntheses, organized by anatomical region, to evaluate and report on the evidence base for chiropractic care. This article is the outcome of this charge. As part of the CCGPP process, preliminary drafts of these articles were posted on the CCGPP Web site www.ccgpp.org (2006-8) to allow for an open process and the broadest possible mechanism for stakeholder input. RESULTS A total of 887 source documents were obtained. Search results were sorted into related topic groups as follows: randomized controlled trials (RCTs) of LBP and manipulation; randomized trials of other interventions for LBP; guidelines; systematic reviews and meta-analyses; basic science; diagnostic-related articles, methodology; cognitive therapy and psychosocial issues; cohort and outcome studies; and others. Each group was subdivided by topic so that team members received approximately equal numbers of articles from each group, chosen randomly for distribution. The team elected to limit consideration in this first iteration to guidelines, systematic reviews, meta-analyses, RCTs, and coh ort studies. This yielded a total of 12 guidelines, 64 RCTs, 13 systematic reviews/meta-analyses, and 11 cohort studies. CONCLUSIONS As much or more evidence exists for the use of spinal manipulation to reduce symptoms and improve function in patients with chronic LBP as for use in acute and subacute LBP. Use of exercise in conjunction with manipulation is likely to speed and improve outcomes as well as minimize episodic recurrence. There was less evidence for the use of manipulation for patients with LBP and radiating leg pain, sciatica, or radiculopathy.

Review of methods used by chiropractors to determine the site for applying manipulation

BackgroundWith the development of increasing evidence for the use of manipulation in the management of musculoskeletal conditions, there is growing interest in identifying the appropriate indications for care. Recently, attempts have been made to develop clinical prediction rules, however the validity of these clinical prediction rules remains unclear and their impact on care delivery has yet to be established. The current study was designed to evaluate the literature on the validity and reliability of the more common methods used by doctors of chiropractic to inform the choice of the site at which to apply spinal manipulation.MethodsStructured searches were conducted in Medline, PubMed, CINAHL and ICL, supported by hand searches of archives, to identify studies of the diagnostic reliability and validity of common methods used to identify the site of treatment application. To be included, studies were to present original data from studies of human subjects and be designed to address the region or location of care delivery. Only English language manuscripts from peer-reviewed journals were included. The quality of evidence was ranked using QUADAS for validity and QAREL for reliability, as appropriate. Data were extracted and synthesized, and were evaluated in terms of strength of evidence and the degree to which the evidence was favourable for clinical use of the method under investigation.ResultsA total of 2594 titles were screened from which 201 articles met all inclusion criteria. The spectrum of manuscript quality was quite broad, as was the degree to which the evidence favoured clinical application of the diagnostic methods reviewed. The most convincing favourable evidence was for methods which confirmed or provoked pain at a specific spinal segmental level or region. There was also high quality evidence supporting the use, with limitations, of static and motion palpation, and measures of leg length inequality. Evidence of mixed quality supported the use, with limitations, of postural evaluation. The evidence was unclear on the applicability of measures of stiffness and the use of spinal x-rays. The evidence was of mixed quality, but unfavourable for the use of manual muscle testing, skin conductance, surface electromyography and skin temperature measurement.ConclusionsA considerable range of methods is in use for determining where in the spine to administer spinal manipulation. The currently published evidence falls across a spectrum ranging from strongly favourable to strongly unfavourable in regard to using these methods. In general, the stronger and more favourable evidence is for those procedures which take a direct measure of the presumptive site of care– methods involving pain provocation upon palpation or localized tissue examination. Procedures which involve some indirect assessment for identifying the manipulable lesion of the spine–such as skin conductance or thermography–tend not to be supported by the available evidence.

Maturation in Rate of High-Velocity, Low-Amplitude Force Development

OBJECTIVES The purpose of this study was to examine the maturation of force development during a thoracic high-velocity, low-amplitude displacement procedure at stages throughout chiropractic education. The hypothesis posed a natural development in rate of force directly related to the duration of experience. The analysis sought to define interrelationships between key characteristics within the procedure. METHODS Fifty volunteers (17 women and 33 men) from a Canadian chiropractic college participated in this study. Participants were block randomized into 5 cohorts of 10 subjects, representing years 1 to 4 and graduates with more than 5 years of practice experience. Participants performed a hypothenar transverse push procedure on the upper thoracic spine, with the subjects lying on a force-sensing table. The average of 3 force-time profiles of the procedures was compared across cohorts using analysis of variance for differences between groups, and pairwise comparisons by Scheffé test, using Holms method for P value adjustment. RESULTS Peak force, force rate, and rise time revealed strong differences based on cohort (P < .001). A natural maturation in high-velocity, low-amplitude force development occurs during training. Little change in peak force occurs in the first 2 years. The majority of development occurs in year 3, with tapering through year 4. A reciprocal coupling exists between peak force and force rate. CONCLUSIONS Group means revealed statistically significant and monotonic increase in force rate, a decreased rise time, and decreased peak force during delivery of the therapeutic peak force. These differences paralleled growth in experience but with an asymptotic leveling of change between the fourth year of training and 5 years of clinical practice experience. This study showed a systematic maturation in performance associated with educational experience. The reciprocal coupling between rate of force development and peak force created a relatively stable impulse.

An analytical model of lumbar motion segment in flexion

OBJECTIVE To develop an analytical model of the lumbar motion segment and to determine the following under the application of flexion physiological loads: (1) the force displacement relationships of the lumbar motion segment; (2) the forces in the ligaments, disc, and facet joints; (3) the strains in the ligaments; and (4) the effect of the transection of the ligaments. DESIGN Computer modeling. SETTING Spinal Ergonomics and Joint Research Laboratory at The National College of Chiropractic. PROCEDURE Computer model simulation of external loads and simulation of ligament transection. MEASURES The following parameters were predicted in flexion by means of a computer model: (1) the load-displacement relationships of the lumbar motion segment; (2) the loads in the ligaments, disc and facet joints; (3) the strains in the ligaments; and (4) the effect of the transection of the ligaments. RESULTS The load sharing among different ligaments predicted by this model under flexion load suggests that the supraspinous ligament carries the greatest load, followed by the yellow ligament, capsular ligament, intertransverse ligament, and interspinous ligament. The ligament strains indicate that the supraspinous ligament undergoes the maximum increase in length, followed by the interspinous ligament, yellow ligament, capsular ligament, and intertransverse ligament. The transection of ligaments increased the flexibility of the joint, the strains on the rest of the ligaments, the loads on all of the rest of the ligaments, as well as the moment on the disc, but does not significantly affect the compressive load on the disc. CONCLUSIONS The analytical model predicts results similar to the experimental data on cadaver motion segments reported in the literature under flexion moment loads.

Chiropractic in North America: Toward a Strategic Plan for Professional Renewal—Outcomes from the 2006 Chiropractic Strategic Planning Conference

OBJECTIVE This report describes the process, participation, and recommendations of a set of consensus conferences on strategy for professional growth that emphasized elements of public trust and alignment between the chiropractic profession and its stakeholders. METHODS In February and August 2006, an invitational group of leaders in the chiropractic profession convened an ad hoc Chiropractic Strategic Planning Conference. Public notice was given and support solicited through the Foundation of Chiropractic Education and Research. A series of international and interdisciplinary speakers gave presentations on the shifting of external social dynamics and medical culture, illuminating opportunities for the profession to extend its privilege and service. A systematic round-robin discussion was followed by group breakout sessions to develop recommendations on priorities for the profession to respond to challenges and opportunities. Recommendations were reviewed by the group as a whole and voted to consensus requiring more than 70% agreement. RESULTS Participants determined a series of recommendations within 5 key domains for improving health professions practice: education, research, regulation, workplace, and leadership. CONCLUSION The action steps proposed by the Strategic Planning Committee are first steps to provide better service to the public while making use of the inherent strengths of the profession.

Thresholds of skin sensitivity are partially influenced by mechanical properties of the skin on the foot sole

Across the foot sole, there are vibration and monofilament sensory differences despite an alleged even distribution of cutaneous afferents. Mechanical property differences across foot sole sites have been proposed to account for these differences. Vibration (VPT; 3 Hz, 40 Hz, 250 Hz), and monofilament (MF) perception threshold measurements were compared with skin hardness, epidermal thickness, and stretch response across five foot sole locations in young healthy adults (n = 22). Perceptual thresholds were expected to correlate with all mechanical property measurements to help address sensitivity differences between sites. Following this hypothesis, the MedArch was consistently found to be the thinnest and softest site and demonstrated the greatest sensitivity. Conversely, the Heel was found to be the thickest and hardest site, and was relatively insensitive across perceptual tests. Site differences were not observed for epidermal stretch response measures. Despite an apparent trend of elevated sensory threshold at harder and thicker sites, significant correlations between sensitivity measures and skin mechanical properties were not observed. Skin hardness and epidermal thickness appeared to have a negligible influence on VPT and minor influence on MF within this young healthy population. When normalized (% greater or smaller than subject mean) to the subject mean for each variable, significant positive correlations were observed between MF and skin hardness (R2 = 0.422, P < 0.0001) and epidermal thickness (R2 = 0.433, P < 0.0001) providing evidence that skin mechanics can influence MF threshold. In young healthy adults, differences in sensitivity are present across the foot sole, but cannot solely be accounted for by differences in the mechanical properties of the skin.