Three-dimensional head kinematics and cervical range of motion in the diagnosis of patients with neck trauma.

OBJECTIVE: To create a statistical model using three-dimensional (3D) head kinematics and range of motion (ROM) to distinguish between people with whiplash syndrome and asymptomatic controls. STUDY DESIGN: Cross-sectional study to estimate validity of diagnostic measures. METHODS: Fifty-one asymptomatic controls (most of whom were women), 18-35 yr old and 30 matched whiplash trauma patients seeking care from suburban outpatient clinics were sought. 3D kinematic parameters of head motion were obtained during tracking tasks (e.g., flexion, extension, etc.) and cervical ROM was measured via a head mounted inclinometer. Their level of pain and disability was assessed via a self-administered neck disability index questionnaire and visual analog pain scale (VAS). RESULTS: A scoring system of biomechanical abnormalities derived from the vertical piercing point, its second derivative and symmetry during oblique tasks. The scores ranged from a minimum of 0 to a maximum of 3. A cutoff of > or = 0.5 correctly identified the greatest number of subjects and minimized false positives (sensitivity 77%, specificity 82%, likelihood ratio 4.5). ROM performed similarly well at a cutoff of 1 SD below the normative mean (sensitivity 77%, specificity 84%, likelihood ratio 3.9). CONCLUSIONS: There is potential for biomechanical analysis to objectively detect abnormalities. The statistical model yielded moderate to high sensitivity and specificity using 3D helical-axis parameters of the head and standard ROM. The model development will continue via this process in future studies. These data could be a first step toward the creation of useful, noninvasive protocols for the diagnosis and management of soft tissue trauma of the neck.

Instantaneous helical axis estimation from 3-D video data in neck kinematics for whiplash diagnostics.

To date, the diagnosis of whiplash injuries has been very difficult and largely based on subjective, clinical assessment. The work by Winters and Peles Multiple Muscle Systems--Biomechanics and Movement Organization. Springer, New York (1990) suggests that the use of finite helical axes (FHAs) in the neck may provide an objective assessment tool for neck mobility. Thus, the position of the FHA describing head-trunk motion may allow discrimination between normal and pathological cases such as decreased mobility in particular cervical joints. For noisy, unsmoothed data, the FHAs must be taken over rather large angular intervals if the FHAs are to be reconstructed with sufficient accuracy; in the Winters and Peles study, these intervals were approximately 10 degrees. in order to study the movements' microstructure, the present investigation uses instantaneous helical axes (IHAs) estimated from low-pass smoothed video data. Here, the small-step noise sensitivity of the FHA no longer applies, and proper low-pass filtering allows estimation of the IHA even for small rotation velocity omega of the moving neck. For marker clusters mounted on the head and trunk, technical system validation showed that the IHAs direction dispersions were on the order of one degree, while their position dispersions were on the order of 1 mm, for low-pass cut-off frequencies of a few Hz (the dispersions were calculated from omega-weighted errors, in order to account for the adverse effects of vanishing omega). Various simple, planar models relating the instantaneous, 2-D centre of rotation with the geometry and kinematics of a multi-joint neck model are derived, in order to gauge the utility of the FHA and IHA approaches. Some preliminary results on asymptomatic and pathological subjects are provided, in terms of the 'ruled surface' formed by sampled IHAs and of their piercing points through the mid-sagittal plane during a prescribed flexion-extension movement of the neck.

Optoelectric measurement of changes in leg length inequality resulting from isolation tests.

OBJECTIVE: a) Establish a precise, standardized method to assess prone leg alignment changes (functional "leg length inequality"), which have, until now, been reported clinically to occur as a result putative chiropractic subluxation isolation tests [neck flexion (C5) and extension (C1)]; and b) describe differences in leg alignment changes in a group of healthy subjects and patients with chronic spinal complaints. DESIGN: Two group, two isolation tests, descriptive, repeated measure analysis of variance. SETTING: Exercise and Sport Research Institute, Arizona State University. PARTICIPANTS: Eight healthy controls, eight patients with a history of chronic spinal complaints and observable leg alignment reactivity. INTERVENTIONS: Active cervical flexion/extension maneuvers. OUTCOME MEASURES: Optoelectric markers affixed to heels and occiput, as subjects lay prone. Marker locations sampled at 100 Hz for 10 sec during: a) three no movement trials, b) three cervical extension and c) three flexion trials. Data transformed to local reference frame approximately each subject's longitudinal axis prior to analysis. RESULTS: Heel position movement occurred during trials and were highly individualistic. Patients exhibited more asymmetrical movements than the controls during the head-up trials. No differences existed between controls and patients for range of heel displacement or net displacement. CONCLUSIONS: The results of this study allow the following to be concluded: 1) small leg displacements (< 1 mm) were recorded by the optoelectric measurement system; 2) heel position changes during isolation tests were identifiable; 3) as a result of head-up maneuvers, patients exhibited more asymmetrical heel movement than controls (t = 8.743, p < .01); 4) The heel range of motion was not different between the groups; and 5) The net change in heel position was not different between the groups. Patients exhibited more asymmetrical heel motion during head-up isolation tests, suggesting that some phenomena may separate these two groups, warranting future study.

Three-dimensional head axis of rotation during tracking movements. A tool for assessing neck neuromechanical function.

The purpose of this article is to report normal variation in the screw (helical) axis of rotation of the head during various types of natural tracking movements. Nine normal subjects and eighteen subjects with neck injury faced a grid of targets separated by 10-degree intervals, and were instructed to use a head pointer (laser) to track whatever target was lit. Various horizontal, vertical, and oblique target sequences were employed. The normal subjects exhibited several consistent trends in finite screw axis parameter variation: vertical movements have a laterally-directed axis whose midsagittal plane crossing position is a function of the head orientation (typical range C3-T1); oblique movements have a diagonally-directed axis and an even greater orientation-specific range (C1-T1); and horizontal movements have a vertical axis that is modified near horizontal orientation extremes and is asymmetrically influenced by upward and downward bias orientations. Subjects with neck injury were seen to exhibit a variety of abnormal screw axis patterns.

Treatment and biomechanical assessment of patients with chronic sacroiliac joint syndrome.

OBJECTIVE: To evaluate diagnostic and biomechanical correlates and treatment outcomes of manipulative/adjustive care in patients highly selected for sacroiliac joint syndrome (SIJS). DESIGN: Descriptive case series, 1 wk baseline, 1 yr follow-up. SETTING: Private chiropractic practice. PATIENTS: Ten out of 153 consecutive new patients (4 male and 6 female) with "primary," chronic, uncomplicated SIJS were selected over an 11-mo period on the basis of painful SIJ and provocation tests. MAIN OUTCOME MEASURES: Back pain (visual analogue scale), Oswestry disability index, lumbar provocation tests and biomechanical measures of gait and postural sway. INTERVENTION: Six-wk regimen of mechanical force, manually assisted, short lever adjustments (MFMA) with an Activator instrument. RESULTS: Pain decreased significantly from a mean baseline value of 25 to 12 (t = 2.28; p < .05). Likewise, the average disability scores diminished from 28 to 13% (t = 2.3; p < .05), and a reduction in the number of positive provocation tests was noted (Fisher Exact Probability range Z = 0.025-0.045). Gait and sway parameters were indistinguishable from normals, before or after treatment. Response to the 1-yr follow-up questionnaire (6/10) revealed stability of symptoms at a low level. CONCLUSIONS: While the majority of subjects recorded some degree of positive outcome, we conclude that: a) discrete SIJS remains difficult to diagnose, but may be possible by judicious choice of screening tests; b) MFMA may benefit some patients with chronic SIJ pain; and c) gait and sway measurement yielded no correlation with clinical conditions.

Treatment of Bell's palsy by mechanical force, manually assisted chiropractic adjusting and high-voltage electrotherapy.

Bell's palsy is a relatively common, painful, unilateral facial paralysis of unknown etiology. While often claimed to be successfully treated by chiropractic methods, no standard treatment approach is generally recognized within the profession, nor has any report of chiropractic treatment of this condition been reported in the literature. This article discusses two cases of Bell's palsy successfully treated by mechanical force, manually assisted chiropractic adjusting technique combined with high-voltage electrotherapy. While these two cases do not necessarily represent any rule for the chiropractic treatment of Bell's palsy by the methods used, or for other chiropractic methods that may be used, they do represent an initial time/treatment "baseline" by which future inter- and intratechnique comparisons may be made for the determination of relative effectiveness.

Three-dimensional head kinematics and clinical outcome of patients with neck injury treated with spinal manipulative therapy: a pilot study.

OBJECTIVE: Finite helical axis parameters (FHAP) of the cervical spine and clinical measures were obtained to evaluate neck function and the clinical effects of spinal manipulative therapy in patients with "whiplash" (WL) type neck injury. DESIGN: Descriptive case series, 1 yr follow-up. SETTING: Three private chiropractic practices. SUBJECTS: Ten consecutive new patients with a history of neck injury, nine asymptomatic, volunteer controls. INTERVENTIONS: A 6-wk regimen of short lever manually assisted adjustments with an Activator Instrument, while acute, four patients received interferential electrotherapy. MAIN OUTCOME MEASURES: Cervical FHAP during normal movements, neck pain (visual analogue scale), active cervical range of motion and follow-up questionnaire. RESULTS: Based on six patients, the FHAPs appeared to mirror the clinical condition, being markedly deviant from the patterns observed in the control group for at least one or more of the tracking tasks for all but one of the patients. Mean pain scores decreased from 44.1 to 10.5 (t = 4.93; p < .0001) and mean total range of motion increased from 234 to 297 degrees (t = 5.68; p < .0001). At 1 yr, seven respondents noted stability of their symptoms at or near the level reported immediately after the 6-wk treatment period. CONCLUSIONS: Based on these preliminary data: a) FHAPs may aid in diagnosing and monitoring treatment of neck dysfunction, b) spinal manipulative therapy may be beneficial to some patients with neck injury and future study is warranted as a means to promote recovery of patients with neck injuries.

Mechanical force, manually assisted short lever chiropractic adjustment.

OBJECTIVES: Chiropractic mechanical force, manually assisted short lever adjusting is a spinoff of the specific toggle recoil adjusting techniques, which were based on the original chiropractic subluxation theory propounded by Daniel David Palmer in 1895. This article reviews: a) the principles of the chiropractic subluxation complex from the standpoint of its historical origin and present-day scientific status; b) the purpose and objectives of specific spinal manipulative techniques; c) the use of mechanical adjusting instruments to effect a velocity/direction controlled adjustive thrust; and d) an assessment of scientific and clinical data relating to the biomechanical and neurological aspects of mechanical force, manually assisted short lever adjusting. DATA SOURCES: Prime sources were from the National Library of Medicine's on-line Index Medicus database, the Chirolars Research Resource Retrieval database, the Chiropractic Research Abstract Collection and the Chiropractic Library Consortium's reference works. Direct search of other nonindexed chiropractic sources was limited to those available in the collection of the National Institute of Chiropractic Research. Early information never documented by publication was obtained by written personal communication. STUDY SELECTION: The principal author selected articles reporting data (as opposed to anecdotal reports) from conference proceedings and peer-reviewed journals. DATA EXTRACTION: Data quality was assessed based on experimental conditions such as sample size, study design and statistical analysis. DATA SYNTHESIS: While mechanical force, manually assisted short lever adjusting seemingly is capable of beneficially altering the cause/effect relationship of spinal subluxations, more research in the nature of controlled clinical trials is needed to ascertain its benefits in the chiropractic treatment of specific conditions. CONCLUSIONS: Basic research is needed in order to establish the scientific basis for the chiropractic subluxation syndrome regardless of the technique employed.

Interexaminer reliability of an isolation test for the identification of cervical subluxation.

A reliability study was conducted to determine whether prone leg length analysis in association with an isolation test maneuver was reproducible. Seventy-two subjects were evaluated by two examiners on separate occasions for the presence of C1 subluxation. Concordance was assessed by the Kappa statistic, and interexaminer percentage of agreement was compared. Agreement beyond chance for the two groups was K = 0.52, p less than 0.01 and 0.55, p less than 0.001, respectively. The results indicate good reliability using this method of analysis for putative upper cervical subluxation in this patient population. Further investigation is necessary to correlate this method of analysis with the empirical evidence of manipulable lesions or subluxations.