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 less than 0.001) to presence or absence of relaxation in back muscles during flexion. Mean trunk strength ratios were inversely related to disability score (P less than .05), and trunk mobility was meaningfully reduced (P less than .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.

Historical perspective. Joseph Janse.

The purpose of this presentation is to acknowledge the pioneering work of a key historical figure who contributed to the available knowledge in anatomy and biomechanics, developed political and social infrastructure to promote the maturation and standardization of chiropractic education, and influenced a paradigmatic shift away from a monocausal belief in the origin of disease. Literature search and archives retrieval were used. Janse was a man with personal intellectual integrity and whose personal commitment was driven by a family experience. Evidence shows that Janse took bold initiatives to influence the chiropractic profession and give it the opportunity to develop as a legitimate healthcare discipline. Janse was a visionary clinical scientist and educator whose 38-year tenure as president of a chiropractic college enabled him to influence the course and development of his profession.

Manipulative therapy versus education programs in chronic low back pain.

STUDY DESIGN: A randomized trial was conducted on a representative sample of patients with untreated low back pain lasting 7 weeks or longer, or having more than 6 episodes in 12 months. OBJECTIVES: To contrast the effectiveness of manipulation, a manipulation mimic, and a back education program. Methodologic criticisms of earlier studies were addressed. SUMMARY OF BACKGROUND DATA: Published meta-analyses suggest clinical benefit from manipulation for acute patients. Data are inconclusive for patients having symptoms for longer than 1 month. METHODS: A total of 1267 consecutive patients were screened. Block randomization was used to assign 209 qualifying patients to treatment groups. Self-reported pain and activity tolerance served as primary outcome measures. Patients were assessed at enrollment, after 2 weeks of treatment, and again after 2 weeks without treatment. Multiple teams conducted recruitment, randomization, assessment, treatment, and data analysis independently without sharing information. Treatments were carefully described, monitored, and balanced for physician attention and physical contact effects. RESULTS: A total of 81.3% of subjects completed the study. Confounding factors and missing data were identified in approximately 20% of those completing the final follow-up. Analysis of the remaining data was carried out. A strong time effect under treatment was observed. Greater improvement was noted in pain and activity tolerance in the manipulation group. Immediate benefit from pain relief continued to accrue after manipulation, even for the last encounter at the end of the 2-week treatment interval. CONCLUSION: Time is a strong ally of the low back pain patient. In human terms, however, there appears to be clinical value to treatment according to a defined plan using manipulation even in low back pain exceeding 7 weeks' duration.

Biomechanics of spinal manipulative therapy.

BACKGROUND CONTEXT: Modern scientific investigations into spinal manipulative therapy (SMT) began in 1975. Conditions often treated include acute and chronic low back pain, radicular pain, neck pain, and some forms of headache. The field of spinal manipulation has often been treated by the literature, incorrectly, as being homogeneous. Much of the confusion regarding this form of treatment can be traced to the ambiguity surrounding the procedures themselves. This report summarizes the clinical biomechanics of SMT and evidence for its associated manipulable lesion is reviewed. Finally, a classification system based on biomechanics is proposed that may facilitate more detailed research in the future. PURPOSE: A categorization system for SMT was sought that would be more objective than is clinically available. Such a system may serve as a means to strengthen future studies, determine operating principles, applicability, treatment effectiveness, and nature of the manipulable lesion. STUDY DESIGN: Literature synthesis. METHODS: A search of the indexed biomechanical and medical literature as well as a hand search of published works was conducted. The criteria for article selection consisted of studies that included measurements of mechanical characteristics of treatment techniques used under the general headings of SMT or manual therapy. A second set of studies was identified that explored the biomechanics of buckling behavior of vertebral segments as a model of the manipulable lesion. Quantitative characteristics of SMT were extracted and grouped to form a basis for classification. RESULTS: A total of 31 articles were identified that contained quantitative data on the biomechanical properties of SMT methods. An additional seven studies were found that quantified spinal buckling behavior. Common features of SMT procedures lead to a matrix that biomechanically characterizes the types of procedures in use. Buckling behavior was compared qualitatively with clinical observations to form a plausible and evidence-based hypothesis of the manipulable lesion. CONCLUSIONS: There currently are a number of named systems of manual procedures. No current triage system is available that predicts which patient has the greater likelihood of benefiting from manual treatment or the procedure type. The biomechanical parameters of SMT form a systematic characterization of manual procedures. Such a system may be used in future studies to test hypotheses of treatment effect from quantitatively defined procedures.

Use of chiropractic manipulation in lumbar rehabilitation.

The beneficial effects of manipulation in relieving symptoms and enhancing spinal flexibility can be a valuable tool in the transition of persons with low back pain into lumbar rehabilitation programs. Manipulation may hasten their entry into active care, or permit them to complete programs that might otherwise be interrupted by symptomatic recurrence. Manipulation science and technical procedures are reviewed as a basis to help understand the utility of properly integrated chiropractic manipulation strategies.

Application of incremental change strategies in chiropractic and multidisciplinary clinical settings for quality improvement.

Care for low back pain remains a clinical enigma. Its high prevalence and cost to the system warrants attention for improvement. Although, no major recent clinical breakthroughs for resolving back pain have emerged, reducing unnecessary tests, eliminating useless or harmful practices, preventing care dependence, and enhancing coping skills can be useful goals for improving patient outcomes. Quality Improvement (QI) approaches can serve as bridge between clinical intuition and large scale science. Three chiropractic delivery settings including two teaching clinics and one large multidisciplinary spine care center incorporated QI approaches as part of an initiative to improve low back pain care. All clinics were able to implement sustainable process and outcomes improvements.

Biomechanics--review of approaches for performance training in spinal manipulation.

Motor skills development is an inherent part of clinical training in health disciplines. The conscious use of educational theory to ground learning is receiving increasing attention across health care education. There are three distinct, yet overlapping, stages of motor skill learning; the cognitive, the integrative or associative, and the autonomous; in which a contextual framework for learning content may be structured. The learning is associated with a mapping of changes within the central nervous system by the interactive mechanisms of adaptation, use-dependent plasticity and operant reinforcement. Successful skill learning requires a sufficient amount of practice and the implementation of relevant feedback strategies in the form of knowledge of performance (KP) or knowledge of results (KR). There is a natural maturation of skills that may be accelerated by feedback. Several factors contribute to stronger skills development. "Mixture-of-experts" models systematically sequence tasks into logical blocks of theory, practice and student reflection on performance. Feedback should involve both KP and KR that compares performance to a tangible standard. Rehearsals should balance use of simulators and volunteer simulated patients to provide the full range of safe and effective learning opportunities prior to students accepting a role as care givers to the public in any clinical setting.

Objective electromyographic evidence for use and effects of lift therapy.

Thirty nine subjects with chronic low back complaints which were unresponsive to other conservative therapies were tested by postural loading electromyography (EMG) to assess their possible response to lift therapy. Of the 35 subjects included in the study, seven (20%) showed no alteration of their muscular asymmetry during stance with either heel of ischial supports placed unilaterally; 18 (51%) of the remaining 28 subjects demonstrated a balancing of the paraspinal activity as a result of the use of heel lifts, while all 28 (80%) were balanced by an ischial support. It was concluded that lift placement by EMG criteria is more accurate than customary radiographic methods of assessing pelvic tilt and/or sacral unleveling. Further study of EMG lift placement, as well as other possible applications, is warranted.

Studies on the biomechanical effect of a spinal adjustment.

Manual treatment of spinal disorders is perhaps the most well-studied remedy for spine-related disorders. Clinical description and controlled studies provide only limited advances in knowledge because so little is known scientifically about manual treatment methods or the disorders to which they are directed. The common factor for all manual methods is that they apply an external load to the spine and its surrounding tissues. Merging of efforts by basic scientists, engineers and clinician-scientists can resolve some of the underlying scientific ambiguity surrounding these issues. This report reviews the seminal efforts in biomechanics that are emerging to describe and understand the treatment, the spinal disorder for which it is used and the physiological effects of the treatment.

Symptoms of neck artery compromise: case presentations of risk estimate for treatment.

OBJECTIVE: To discuss the use of magnetic resonance angiography (MRA) imaging as a definitive means to assess vascular patency and the relative value of various vertebral artery screening maneuvers. CLINICAL FEATURES: Two female patients suffered head and neck trauma with possible vertebral artery insufficiency. Positive vertebral artery screening tests with consistent symptoms were present in both cases. One patient had a congenitally narrowed vertebral artery, whereas the second had no evidence of vascular anomaly. INTERVENTION AND OUTCOME: Conservative chiropractic management using manipulation and rehabilitation led to favorable outcome in both cases. The patient with vascular compromise received a treatment plan avoiding neck manipulation. The second case received manipulation per clinical indications from neck findings. CONCLUSION: MRA imaging may be more important to critical decision making than are the various vertebral artery screening tests in patients with positional vertigo on combined neck extension and rotation.

Myoelectric paraspinal response to spinal loads: potential for monitoring low back pain.

LBP evaluation has been hampered by the subjectivity of available clinical procedures and the paucity of factual information about spinal dysfunction. Objective indices of spinal pathomechanics would assist the clinician to prescribe and evaluate appropriate treatment. This project assesses paraspinal myoelectric symmetry as a potential objective measure of low back performance. A preliminary group (N = 39) of symptomatic subjects was prospectively tested to choose parameters for the blinded experiment to follow. The experimental group of volunteers (N = 37) were electromyographically monitored while the subjects performed selected postural tasks which did not produce pain. Results were compared to orthopedic tests and history. Four arbitrary myoelectric classifications were defined for subject grouping and comparison: subjects with symmetrical paraspinal task performance, occasional (less than 4 tasks) asymmetry, low amplitude response for quasi-static loads, and large amplitude asymmetry (greater than 4 tasks). Eighty percent of subjects with significant asymmetry of muscle action had recent LBP history. Isolated task testing is inconclusive as a clinical parameter. However, observation of performance of a series of tasks may be useful in clinical diagnosis and monitoring of function in low back pain.

Motions of the head and thorax during neck manipulations.

OBJECTIVE: The purpose of this study was to determine the amplitudes and variations of preload positioning and displacements of the head and thorax during spinal manipulative therapy (SMT) applied to C2. DESIGN: This experimental study measured the biomechanics of SMT applied to C2. SETTING: Biomechanics Laboratory, Mechanical Engineering and Applied Mechanics, University of Michigan and Spinal Ergonomics and Joint Research Laboratory, National College of Chiropractic. PARTICIPANTS: Eighteen healthy volunteers from the University of Michigan and the National College of Chiropractic were manipulated by a total of eight experienced chiropractic physicians licensed in the state in which they participated. INTERVENTION: Sixty-six Direct Break (DB) and twenty-three Rotary Break (RB) diversified procedures were administered to C2. Randomization of the DB was made on two variables, direction and intended load intensities. The RB was administered only from the right by each physician. MAIN OUTCOME MEASURES: Linear and angular displacement time histories for the head and thorax mass centers were monitored during the preload setup of each procedure and the dynamic delivery of the treatment procedures. CONCLUSIONS: DB procedures were found to have sagittally symmetric positioning and displacements as a function of intended direction of the procedure. Both DB and RB methods consisted of preload positioning with head flexion. RB rotation and lateral bending preload positions approached the maximal voluntary ranges of motion for the upper cervical spine. Variations among procedures by one manipulator were approximately the same as for variations among manipulators. Data indicates that SMT procedures can be successfully modified to control amplitude and direction of body segment displacements that arise.

Patient monitoring in the conservative management of cervical radiculopathy.

With increasing frequency, concern is being raised by nonmanipulating health professionals over the use of manual procedures in the cervical spine. With respect to treatment of radicular syndromes secondary to discogenic spondylosis, the potential for occasional iatrogenic complications must be an "a priori" consideration. Illustrated with the data from case presentation, conservative therapeutic management utilizing electrodiagnostic monitoring in questionable cases is discussed. Anecdotal improvement in median nerve F-wave function following conservative treatment including spinal manipulation is presented.

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.

Electrodiagnostic testing in back and extremity pain.

OBJECTIVE: The usefulness of electrodiagnostic testing by the primary care provider is shown in two cases of suspected compression-type neural lesions of the lumbar spine. CLINICAL FEATURES: A 54-yr-old female with acute lumbar spine pain that radiated into the hip and a 26-yr-old male with sharp gluteal pain that radiated into the thigh and ankle were admitted into an inpatient care facility for intensive therapy. Plain film radiographs were obtained initially. In addition, electrodiagnostic testing was performed to evaluate the L5 and S1 nerve roots, which suggested compressive-type lesions. Non-enhanced CT of the lumbar spine was performed and revealed central disk herniation or protrusion in each case. INTERVENTION AND OUTCOME: One patient exhibiting central compression signs of bladder dysfunction was referred for medical intervention. The remaining patient received flexion-distraction type of chiropractic manipulation with physiologic therapeutics and was discharged to outpatient care after 16 days. CONCLUSIONS: Electrodiagnostic testing can provide the primary care provider the data needed to make an informed decision regarding advanced imaging studies and to institute appropriate therapy or to intelligently refer a patient for follow-up.

Sensitivity study of H-reflex alterations in idiopathic low back pain patients vs. a healthy population.

Twenty-seven male and 12 female healthy volunteers were tested twice with 2-7 days separation. Hoffman (H) reflexes and muscle (M) activation waves were obtained from the posterior tibial nerves bilaterally. Results were compared to those obtained from patients presenting with a complaint of low back and/or leg pain, without compressive neuropathy. M, F, H latencies and H/Mmax ratio were recorded. H/M ratio and latency comparisons were not significantly different in the control group left to right or test to test. For the low back pain group, 10-14 days following the initial evaluation, each subject returned for a follow-up test. During the interim, the patient was followed conservatively using manipulation and home care. Analysis of variance (ANOVA) testing of ratio values demonstrated a difference in overall mean values (p greater than 0.001) for comparisons between the control (mean = 0.367), pretest (mean = 0.695), and posttest (mean = 0.558) values. Sensitivity in discriminating acute low back pain subjects from healthy controls was tested by determining the distance between mean H/M values for the probability curves of each population, with an arbitrary cutoff value of 0.6 as the upper limit normal. Sensitivity distance was 2.29 with a likelihood ratio of 3.04. This suggests that an H/Mmax ratio greater than or equal to 0.6 will correctly identify two of three patients with idiopathic low back pain.

Differences in treatment history with manipulation for acute, subacute, chronic and recurrent spine pain.

Preference for treatment protocols used in the care of spine disorders are based more upon clinical impressions than upon systematic study of the pathology or treatment efficacy. As social emphasis moves to cost containment strategies, quantitative data is necessary to give guidance for rational policy decisions. This study sets a description of the clinical experience obtained in a group practice, teaching clinic engaged in management of spine disorders. The same subjects were separately reported as being broadly representative of those seen in private using a cash payment policy. Clinical characteristics were quantified on 241 patients. A total of 149 volunteered to complete follow up evaluations. The total number of treatment sessions were tallied to case resolution on all 241 patients and were evaluated by stratifying them according to chronicity of the chief complaint. The range of treatment for all cases was 1-22. Chronic complaints required the most care, with a mean of 8.2 sessions (F = 2.833, p = .014). Thoracic disorders required approximately half the care as lordotic spine regions (F = 2.372, p = .04). No differences were observed based upon descriptive classifications of entrapment, mechanical or muscular pain. All but 25 cases reached resolution well within 6 wk, requiring a mean of 3.8 (range 1-11) additional treatment sessions.