Interexaminer reliability of supine leg checks for discriminating leg-length inequality.

OBJECTIVE: The purpose of this study was to quantify interexaminer reliability of a standardized supine leg check procedure used to screen for leg-length inequality. METHODS: Two doctors of chiropractic used a standardized supine leg check procedure to examine 50 volunteers for leg-length inequality. The order of examination was randomized. The side and magnitude of leg-length inequality were determined to the nearest 1/8 in. Subjects and examiners were blinded. Interexaminer reliability was assessed with a Bland-Altman plot, tolerance table of absolute differences, a quadratic weighted κ statistic for quantitative scores, and a Gwet's first-order agreement coefficient for dichotomous ratings. RESULTS: The quadratic weighted κ statistic to quantify the reliability of the rating scale was 0.44 (95% confidence interval, 0.21-0.67), indicating moderate reliability. The 2 examiners agreed exactly 32% of the time, within 1/8 in 58% of the time, within 3/16 in 72% of the time, and within 3/8 in 92% of the time. The Bland-Altman plot revealed possible heterogeneity in reliability that requires additional study. The examiners agreed on the presence of a leg-length inequality of at least 1/8 in in 40 (80%) of 50 subjects (first-order agreement coefficient, 0.76), suggesting good agreement for this diagnostic category. CONCLUSION: The examiners showed moderate reliability in assessing leg-length inequality at 1/8-in increments and good reliability in determining the presence of a leg-length inequality.

Interexaminer reliability of a leg length analysis procedure among novice and experienced practitioners.

OBJECTIVE: The purpose of this study was to evaluate the interexaminer reliability of a leg length analysis protocol between an experienced chiropractor and an inexperienced chiropractic student who has undergone an intensive training program. METHODS: Fifty participants, aged from 18 to 55 years, were recruited from the New Zealand College of Chiropractic teaching clinic. An experienced chiropractor and a final-year chiropractic student were the examiners. Participants were examined for leg length inequality in the prone straight leg and flexed knee positions by each of the examiners. The examiners were asked to record which leg appeared shorter in each position. Examiners were blinded to each other's findings. kappa statistics and percent agreement between examiners were used to assess interexaminer reliability. RESULTS: kappa analysis revealed substantial interexaminer reliability in both leg positions and also substantial agreement when straight and flexed knee results were combined for each participant. kappa scores ranged from 0.61, with 72% agreement, for the combined positions to 0.70, with 87% agreement, for the extended knee position. All of the kappa statistics analyzed surpassed the minimal acceptable standard of 0.40 for a reliability trial such as this. CONCLUSION: This study revealed good interexaminer reliability of all aspects of the leg length analysis protocol used in this study.

Interexaminer reliability of the prone leg length analysis procedure.

OBJECTIVE: The purpose of this study was to perform an interexaminer reliability evaluation of the prone leg length analysis procedure. METHODS: Two chiropractors each examined a series of 45 patients with a history of low back pain. Patients were in the prone position, with the knees in both extended and flexed positions, and with the head rotated right and left. The clinicians were asked to determine the side of the short leg with knees extended and if a change in leg length occurred with head rotation or when the knees were flexed. They were also asked to visually judge the amount of leg length differential by categorizing the difference as either less than 0.25, 0.25 to 0.5, 0.5 to 0.75, or more than 0.75 in. The head rotation portion of the test was performed only with patients (n = 22) in whom the leg length differential was determined to be less than 0.25 in. RESULTS: kappa statistics and frequency distributions were calculated for each of the respective observations. Reliability of determining the side of the short leg with knees extended was good at 82% agreement (kappa = 0.65) but fair for determining the amount of leg length difference at 67% agreement (kappa = 0.28). Reliability of the head rotation testing procedure was extremely poor, with only 50% and 45% agreement about the observed change in leg length with the head rotated left and right, respectively (kappa = 0.04, kappa = -0.195). There was no significant correlation found between the side of reported pain by the patient and the side of the short leg as noted by either clinician (chi2 = 0.55, P = .91, and chi2 = 1.55, P = .67). All of the patients (100%) were judged to have a leg length difference by both clinicians. When the knees were flexed, there was 93% agreement that the short leg became longer (43/45 cases), with no reported cases of the short leg getting shorter. Calculation of kappa statistics was confounded for these last 2 observations because of extremely high prevalence bias. CONCLUSIONS: The results indicate that 2 clinicians show good reliability in determining the side of the short leg in the prone position with knees extended but show poor reliability when determining the precise amount of that leg length difference. The head rotation test for assessing changes in leg length was unreliable in this sample of patients. There does not appear to be any correlation between the side of pain noted by the patient and the side of the short leg as observed by the clinicians; all 45 patients in this sample were found to have a short leg by both clinicians.

Segmental haemangioma of infancy of the lower limb with skeletal overgrowth.

A female infant presented at 3 months of age with vascular lesions involving the left lower limb and left side of the vulva. At birth, the left leg was thinner than the right, but equal in length. She had macular, reticulate, bluish discolouration covering most of the skin of the involved leg with superimposed cherry-red papules, most dense over the proximal portion. The macular component showed evidence of improvement within the first few months of life. Papular and nodular components over the leg and the vulva progressively increased in size and thickness until the age of 10 months. These elements had the appearance and behaviour typical of haemangioma of infancy. Regression of these lesions started at the age of 15 months. By the age of 6.5 months, the involved leg was no longer thinner than the right, but the left leg and foot had grown longer. Leg length discrepancy peaked at 2.4 cm at the age of 2 years. The most rapid phase of relative growth discrepancy of left and right leg bones was contemporaneous with the growth phase of the haemangioma. Radiological investigations and histopathology have been consistent with haemangioma of infancy. GLUT-1 immunostaining of the lesion was positive.

Interexaminer reliability and validity for diagnosis of temporomandibular disorders of visual leg measurements used in dental kinesiology.

AIMS: To determine the reliability and the validity of visual leg measurements used in dental kinesiology, which suggests that a masticatory dysfunction, such as occurs in temporomandibular disorders (TMD), can influence the length and the internal rotation of lower limbs. METHODS: The leg-length inequality test and the internal foot-rotation test were performed independently by 3 different examiners on 41 subjects who were also screened for TMD. Data were analyzed by means of kappa statistics and by calculation of sensitivity and specificity values. RESULTS: Chance-corrected reliability was generally poor for both the leg-length inequality test (0.33 < or = k < or = 0.39) and the internal foot-rotation test (0.15 < or = k < or = 0.27). Sensitivity and specificity values of the tests to differentiate TMD and healthy subjects were below acceptable thresholds; they ranged from 0.41 to 0.57. CONCLUSION: Visual evaluations of leg-length inequality and internal foot rotation were unreliable and are not valid for TMD diagnoses. The results of chiropractic visual leg measurement procedures in dentistry should be interpreted with caution, particularly when clinical decisions may lead to nonreversible dental treatment.

Status of activator methods chiropractic technique, theory, and practice.

OBJECTIVE: To provide an historical overview, description, synthesis, and critique of the Activator Adjusting Instrument (AAI) and Activator Methods Chiropractic Technique of clinical assessment. METHODS: Online resources were searched including Index to Chiropractic Literature, EBSCO Online, MANTIS, CHIROLARS, CINAHL, eJournals, Ovid, MDConsult, Lane Catalog, SU Catalog, and Pubmed. Relevant peer-reviewed studies, commentaries, and reviews were selected. Studies fell into 2 major content areas: instrument adjusting and the analysis system for therapy application. Studies were categorized by research content type: biomechanical, neurophysiological, and clinical. Each study was reviewed in terms of contribution to knowledge and critiqued with regard to quality. DISCUSSION: More than 100 studies related to the AAI and the technique were found, including studies on the instrument's mechanical effects, and a few studies on clinical efficacy. With regard to the analysis, there is evidence for good reliability on prone leg-length assessment, but to date, there is only 1 study evaluating the Activator Methods Chiropractic Technique analysis. CONCLUSION: A body of basic science and clinical research has been generated on the AAI since its first peer-reviewed publication in 1986. The Activator analysis may be a clinically useful tool, but its ultimate scientific validation requires testing using sophisticated research models in the areas of neurophysiology, biomechanics, and statistical analysis.

Validity of compressive leg checking in measuring artificial leg-length inequality.

OBJECTIVE: To determine the accuracy of instrumented prone compressive leg checking. DESIGN: Repeated measures (n = 26) on single subjects (n = 3). SETTING: Chiropractic college research clinic. METHODS: A pair of surgical boots were modified to permit continuous measurement of leg-length inequality (LLI). Multiple prone leg-check observations of a blinded examiner on 3 subjects were tested against artificial LLI that was created by randomly inserting 0 to 6 1.6-mm shims in either boot. Accuracy was assessed both within observations (observed versus artificial LLI) and between observations (observed versus artificial changes in LLI). The intraclass correlation coefficient (ICC), Lin's concordance correlation coefficient (CCC), Bland-Altman limits of agreement, and linear regression statistics were obtained to determine the reliability and validity of compressive leg checking compared to a reference standard. RESULTS: For each shim condition, test-retest reliability was excellent (ICC =.85 and CCC = 0.95). The 95% confidence interval for the limits of agreement for observed versus artificial change in LLI was -5.44 to 5.67. The observed and artificial LLI shared 87% of their variation within observations (n = 78) and 88% between observations (n = 75). The mean examiner error was 1.72 mm and 2.01 mm, respectively. CONCLUSION: Compressive leg checking seems highly accurate, detecting artificial changes in leg length +/-1.87 mm, and thus possesses concurrent validity assessed against artificial LLI. Pre-leg-check and post-leg-check differences should exceed 3.74 mm to be confident a real change has occurred. It is unknown whether compressive leg checking is clinically relevant.

Calcitonin administration in a rabbit distraction osteogenesis model.

The effect of salmon calcitonin on the maturation of the regenerate bone was assessed in an experimental model in rabbits. Twenty-six New Zealand White male rabbits, approximately 5 months old and weighing 3 to 3.5 kg, were subjected to a mid-diaphyseal tibial osteotomy. After 5 days, the right tibia was lengthened gradually at a rate of 0.375 mm every 12 hours, for 10 days. Ten international units of salmon calcitonin were administered daily subcutaneously to the study group (14 animals), whereas the animals of the control group (12 animals) were injected with a placebo, for the duration of the experiment. The bone mineral density of the regenerate bone was assessed on Days 20, 35, 45, and 55 of the experiment, in both groups, using dual energy xray absorptiometry. No statistical significant difference was found in the dual energy xray absorptiometry measurements between the study and control groups regarding the change of the bone mineral density of the new bone relative to a preoperative baseline measurement. Characteristic time-related changes were observed in the bone mineral density of the regenerate bone during its maturation, which proved to be identical in both groups. It seems that the administration of calcitonin does not enhance regenerate bone mineralization rate and tendency during bone lengthening.

Reliability of chiropractic methods commonly used to detect manipulable lesions in patients with chronic low-back pain.

OBJECTIVE: To assess the intraexaminer and interexaminer reliability of a multidimensional spinal diagnostic method commonly used by chiropractors. DESIGN: An intraexaminer and interexaminer Latin square, repeated measures reliability study. The techniques of diagnosis under investigation included visual postural analysis, pain description by the patient, plain static erect x-ray film of the lumbar spine, leg length discrepancy, neurologic tests, motion palpation, static palpation, and orthopedic tests. PARTICIPANTS: Three experienced chiropractors examined 19 patients, and 2 experienced chiropractors examined 10 and 9 patients, respectively, who were suffering from chronic mechanical low-back pain. RESULTS: Intraexaminer reliability of the decision to manipulate a certain spinal segmental level was moderate (kappa = 0.47). The interexaminer agreement pooled across all spinal joints indicated fair agreement (kappa = 0.27). Interexaminer reliability for individual examiner pairs for the L4/L5 segmental level was slight (kappa = 0.09). At the L5/S1 level, the interexaminer reliability was fair (kappa = 0.25). For the sacroiliac joints, interexaminer reliability was slight (kappa = 0.04 and 0.14). CONCLUSION: This study of commonly used chiropractic diagnostic methods in patients with chronic mechanical low-back pain to detect manipulable lesions in the lower thoracic spine, lumbar spine, and the sacroiliac joints has revealed that the measures are not reproducible. The implementation of these examination techniques alone should not be seen by practitioners to provide reliable information concerning where to direct a manipulative procedure in patients with chronic mechanical low-back pain.

Comparison of leg length inequality measurement methods as estimators of the femur head height difference on standing X-ray.

OBJECTIVE: To assess the validity and reliability of prone and supine measurements of leg length inequality and to determine the potential use of measurements at the iliac crests and patient demographics as predictors to estimate standing leg length differential. DESIGN: Repeated prone and supine measurements of leg length inequality were made by an experienced chiropractor and compared with iliac crest and femur head measurements made on X-rays of standing patients. Multiple regression analysis was performed. SETTING: Private chiropractic practice. PARTICIPANTS: The first 50 new patients with low back pain that were X-rayed were included in the study. RESULTS: Intraexaminer reliability was excellent for the prone measurements. The supine tests were less reliable. The prone measurements were highly correlated with the standing X-ray femur head measurement. The supine measurements were poorly correlated. Measurements of deficiency at the iliac crests on X-ray were most highly correlated with X-ray measurements of discrepancy. In multiple regression, the prone measurements and duration of problem were the only significant predictors of standing X-ray difference. CONCLUSIONS: In this study, crest measurements were made on X-ray; the degree of accuracy with which millimeter differences can be measured clinically on patients is unknown. In a few cases, the supine measurements were more accurate than the prone; however, the supine test validity was poor when compared with the standing X-ray measurements, and reliability was less than expected. Supine measurements should not be used to estimate standing leg length discrepancy in new low back pain patients but perhaps can be used in other clinically meaningful ways. Intraexaminer reliability of the prone measurements was higher, but further investigations need to focus on interexaminer reliability. The prone measurement as a predictor holds promise, but new measurement tools must be developed.

The validity of the prone leg check as an estimate of standing leg length inequality measured by X-ray.

OBJECTIVE: To determine if prone leg length measurements for inequality are valid to estimate standing X-ray measured differences. DESIGN: Leg length inequality (LLI) was measured, in millimeters, with each patient prone and with a standing X-ray, by an experienced chiropractor. Correlation between the two was calculated, and dependent t test performed. SETTING: Private chiropractic practice. PARTICIPANTS: The first 50 new patients with low back pain (LBP) who were X-rayed were included in the study. RESULTS: Correlation between the two variables was 0.71. Standard error of estimation was 5.4 mm. In 54% of subjects, the prone measurement was within 3 mm of the X-ray LLI; in 12%, however, opposite legs were identified as being "shorter" between the two methods. In 76% of patients, prone measurements were within 6 mm of X-ray, but there was 12-mm difference between the two measurement methods in 8% of the comparisons. CONCLUSIONS: Despite positive correlation, prone leg length measurements for inequality are not entirely valid estimates of standing X-ray differences. Large differences between prone and X-ray measurements in some cases indicate that one should be cautious when using the prone method alone to estimate leg length discrepancy. Additional research is needed to determine the causes of measurement differences between the two methods. Other methods for estimating standing leg length differential must be developed and evaluated for validity.

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.

Leg length inequality.

OBJECTIVE: The (Pacific) Consortium for Chiropractic Research has taken the initiative to research, investigate and provide information directed toward health care accountability, including evaluation of health care measures and practices. This article is a review of the literature pertaining to leg length inequality (LLI). Leg length measures are utilized by various health care providers as an indicator of biomechanical imbalance and necessity for care. Following the overview of the incidence, classifications and clinical significance, emphasis was placed on methods of evaluation, especially the visual "quick" leg length measurement procedure. Finally, a brief section on conservative care has been provided. DATA SOURCES: The information and studies reviewed were obtained from Medline, the Index to Chiropractic Literature, Chiropractic Research Archives Collection, Physiotherapy Index, Chiropractic Literature Analysis and Retrieval System, various technique manuals, personal communication with technique research advisors, proceedings and dissertations. REFERENCE SELECTION: In spite of the widespread use of leg length measures, there is still much controversy associated with LLI, its biomechanical significance and the reliability of the various measurement systems employed. Therefore, the 182 references utilized were selected on the basis of applicable information, especially studies that provided a detailed methodological design with statistical analysis regarding evaluation procedures. CONCLUSION: There appears to be a lack of agreement concerning incidence, classification and point of clinical significance. However, the manifestations or consequences of LLI demonstrate greater accordance. Of the three most commonly utilized evaluation methods, radiographic measures such as the scanograms are recognized as the most reliable procedure for the evaluation of anatomical LLI. Much controversy exists with some of the clinical orthopedic methods and the visual "quick" leg check. Because there is such a vast range in estimates of reliability, few if any definitive conclusions can be made regarding these methods. Given this, it is evident that more research is needed before the use of certain orthopedic and visual checks are considered reliable and valid.

Precise measurement of functional leg length inequality and changes due to cervical spine rotation in pain-free students.

A series of blinded studies to determine the feasibility of documenting functional leg length inequalities and changes in functional leg length in normal and non-normal patients were performed. A new apparatus designed to minimize or eliminate subjective components of inequality assessment, while attaining high levels of precision, was developed. Subjects were evaluated for presence of cervical spine lesion by five independent examiners and grouped into "lesioned" and "nonlesioned" categories. Subjects' leg length inequalities were measured by different evaluators as well as multiple measurements by a single evaluator to determine interrater and intrarater reliability coefficients. Measurements were taken on both flat and hi-low tables for changes during active cervical spine rotation. In addition, leg length measurements were taken during induced tetanic contraction by ipsilateral galvanic paravertebral muscle stimulation. Results indicated an absence of any significant effect of head rotation, type of table, galvanic stimulation, or any difference between persons classified as cervically lesioned or not cervically lesioned. Interrater and intrarater reliability coefficients for the measuring apparatus were statistically significant with small error variances. Failure to obtain subjects with frank pain as well as absence of an applied cephalad pressure (as is performed clinically) during leg length evaluation were considered as possible explanations for the failure to detect an effect of head rotation in the leg lengths. Discussion addresses the need for sensitive leg length inequality assessment techniques which eliminate subjectivity and contribute to decreased error variances.

Reliability of the Derifield-Thompson test for leg length inequality, and use of the test to demonstrate cervical adjusting efficacy.

The Derifield-Thompson test for leg length inequality (LLI) is commonly used by chiropractors to assess a need for adjustment and to evaluate the results of adjustment. The two previous studies testing the reliability of the technique reported conflicting results. This study had two objectives: to demonstrate inter- and intraobserver reliability in detecting a LLI as little as 3 mm; and to document what effect Pierce-Stillwagon cervical adjusting has on a functional LLI. Twenty-six subjects walked into five successive examining rooms where a Derifield leg check was performed, including an estimate of the millimeters of difference in leg lengths. The subjects then entered a treatment room where they were randomly given no treatment, cervical adjusting, or gluteal massage. This process continued for 5 cycles. This study demonstrated that clinicians could reliably measure a LLI to less than 3 mm (both inter- and intraobserver), and also detect a change in LLI when the head was rotated. Neither cervical adjustment nor gluteal massage produced a significant change in observed LLI.