OBJECTIVE Although it is common to find assertions relating functional leg length inequality (LLI) to pelvic torsion and other states of subluxation, comments and/or data concerning anatomical LLI in this same context are uncommon. This review of the literature synthesizes the evidence on pelvic torsion in relation to anatomical LLI. METHODS The literature was searched using the PubMed; Manual, Alternative, and Natural Therapy Index System; Allied and Complementary Medicine Database; Cumulative Index to Nursing and Allied Health Literature; and Index to Chiropractic Literature databases for primary studies that related LLI, either artificially created or naturally occurring, to pelvic torsion. Extracted data included natural vs artificial LLI, method of creating or detecting LLI, subject selection, methodology for measuring pelvic torsion, and results. RESULTS Nine English-language studies were retrieved published 1936-2004. Seven determined the impact of artificial, transient LLI on pelvic torsion, whereas 2 studied the effect of naturally occurring LLI. CONCLUSION Across varying methodologies for measuring LLI and pelvic torsion, a consistent, dose-related pattern was identified in which the innominate rotates anteriorly on the side of a shorter leg and posteriorly on the side of the longer leg. This finding was contrary to the common assertion that the ilium rotates posteriorly on the side of a short leg and vice versa. Practitioners of manual medicine who derive vectors for intervention based on leg checking procedures should consider the possibility that the direction of pelvic torsion may be variable depending on whether the LLI is of anatomical or functional origin.

The use of accurate and reliable clinical and imaging modalities for quantifying leg-length discrepancy (LLD) is vital for planning appropriate treatment. While there are several methods for assessing LLD, we questioned how these compared. We therefore evaluated the reliability and accuracy of the different methods and explored the advantages and limitations of each method. Based on a systematic literature search, we identified 42 articles dealing with various assessment tools for measuring LLD. Clinical methods such as use of a tape measure and standing blocks were noted as useful screening tools, but not as accurate as imaging modalities. While several studies noted that the scanogram provided reliable measurements with minimal magnification, a full-length standing AP computed radiograph (teleoroentgenogram) is a more comprehensive assessment technique, with similar costs at less radiation exposure. We recommend use of a CT scanogram, especially the lateral scout view in patients with flexion deformities at the knee. Newer modalities such as MRI are promising but need further investigation before being routinely employed for assessment of LLD. Level of Evidence: Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

BACKGROUND Leg-length inequality is most often divided into two groups: anatomic and functional. Part I of this review analyses data collected on anatomic leg-length inequality relative to prevalence, magnitude, effects and clinical significance. Part II examines the functional "short leg" including anatomic-functional relationships, and provides an outline for clinical decision-making. METHODS Online database--Medline, CINAHL and MANTIS--and library searches for the time frame of 1970-2005 were done using the term "leg-length inequality". RESULTS AND DISCUSSION Using data on leg-length inequality obtained by accurate and reliable x-ray methods, the prevalence of anatomic inequality was found to be 90%, the mean magnitude of anatomic inequality was 5.2 mm (SD 4.1). The evidence suggests that, for most people, anatomic leg-length inequality does not appear to be clinically significant until the magnitude reaches approximately 20 mm (approximately 3/4"). CONCLUSION Anatomic leg-length inequality is near universal, but the average magnitude is small and not likely to be clinically significant.

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.

OBJECTIVE To determine the incidence of pelvic unleveling, foot rotation, and supine leg length alignment asymmetry in a nonclinical population and to examine the validity (sensitivity, specificity, positive and negative predictive values) of these visual tests and their relationship to self-reported back pain. DESIGN Volunteers answered a questionnaire regarding back pain and were then examined by a chiropractor who was unaware of the status of their back pain. PARTICIPANTS Seventy-four unscreened volunteers answered the questionnaire. MAIN OUTCOME MEASURES The association of visual tests with back pain and their validity indices; Visual Analogue Scale ratings. RESULTS Fifty-one percent (n = 74) of volunteers examined had supine leg length alignment asymmetry (LLA). Pain intensity on a Visual Analogue Scale was significantly higher (P <.001) for those demonstrating supine LLA than for those without LLA. Those with back pain and recurrent back pain were significantly (P <.001) more likely to have supine LLA. The validity indices of the supine leg check showed acceptable levels for sensitivity (74%), specificity (78%), and positive predictive value (82%)[corrected] in recurrent back pain. Findings also indicated a high incidence of supine LLA in volunteers with chronic back pain (85%). CONCLUSION The results indicated that, in this group of volunteers, the supine leg length alignment check had clinical validity as a stand-alone test for recurring back pain. Further testing on a larger, statistically defined cross-section of the population is recommended.

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.

Application of previous findings regarding muscle strength and function in scoliotics suggests that curvature might result from unbalanced pull of spinal muscles oriented transversely. This study investigated the role of muscle strength and strength symmetry in 48 young female scoliotics and 48 age-matched controls. The subjects were divided into three age levels: 11 and 12, 13, and 14 and 15 years of age. Scoliotics were weaker than the nonscoliotics only for shoulder strength in the two older age levels. For all subjects combined, as well as each group and age level, the dominant versus nondominant strength differences were significantly greater than zero; however, the magnitudes of the differences were not different between any of the groups. Nonscoliotics displayed significantly greater trunk flexibility than scoliotics. J Orthop Sports Phys Ther 1991;14(4):144-148.

This study examined the effects of ingesting beverages of varying electrolyte-carbohydrate (ECHO) composition on hydration, sensory response, physiological function, and work performance during 4 hours of simulated industrial work for subjects wearing impermeable protective clothing (PC). Male subjects (N=18) completed four separate work sessions. Each session consisted of 30 min of treadmill walking with intermittent arm curls at 300 kcal per hour (moderate work rate), followed by 30 min of rest, for a total of 4 hours at 33 degrees C wet-bulb globe temperature. Excessive physiological strain prevented only four subjects from completing the 4-hour protocol. A different beverage was provided for consumption ad libitum for each work trial in a repeated measures, double-blind design. The beverages included lime colored water (W), lemon-lime placebo (P), lemon-lime ECHO with 18 mEq/L NaCl (ECHO18), and lemon-lime ECHO with 36 mEq/L NaCl (ECHO36). There was no difference in sweat production among the four trials (p = 0.61). Mean (standard deviation [SD]) fluid consumption was significantly greater for the ECHO36 [771 (+/-264) mL per hour] as compared with the W [630.6 (+/-234) mL per hour] and the P [655.2 (+/-228) mL per hour](p<0.05), but not significantly greater than the ECHO18 [740.4 (+/-198) mL per hour]. Also, consumption of the ECHO18 was significantly greater than the W. Mean (SD) weight change, expressed as a percentage of total body weight (pre minus post), was -0.55(+/-0.8) for W,-0.31(+/-1.0) for P,-0.01(+/-1.1) for ECHO18, and +0.11(+/-1.1) for ECHO36 (p = 0.06). Subjects drank less and tended to experience greater weight loss in trials in which W or P were provided compared with trials in which either ECHO was provided. Thus, ECHO beverages, when provided ad libitum to workers wearing PC in a hot environment, produced better hydration than water.

PURPOSE. Researchers who studied the effects of rebound exercise on fitness have concluded that the intensity of rebound exercise elicited only minimal improvements in fitness. This study determined how the addition of arm pumping with handheld weights (HHW) would increase exercise intensity while rebounding. METHODS. Fifteen male subjects (20 to 43 years) ran in place on a mini-trampoline at a stride frequency of 120 foot strikes per minute, with the sole of the foot 15 cm above the rebounder rim. Oxygen uptake (VO2) and heart rate (HR) were measured while rebounding alone, and also while pumping 0.45 kg, 0.91 kg, and 1.36 kg HHW to heights of 61 and 91 cm. RESULTS. All combinations of weights and pumping levels resulted in significantly (P <.05) higher VO2 and HR than rebounding alone. The estimated mean increase in VO2 was 3.2 mL/kg/min when the weight was increased from 0.91 kg to 1.36 kg at the 91 cm pumping height. The corresponding HR increase was 10.1 bpm. Similarly, when 1.36 kg weights were pumped at 91 cm instead of 61 cm, the mean increase in VO2 and HR was 6.2 mL/kg/min and 11.4 bpm, respectively. CONCLUSIONS. The addition of HHW exercise to rebounding substantially increases exercise intensity. Because rebounding without weights results in a relatively low intensity, the addition of HHW should be considered in the use of rebounding for cardiovascular training.

This study investigates the utility of two equations for predicting minimum wrestling weight and three equations for predicting body density for the population of high school wrestlers. A sample of 54 wrestlers was assessed for body density by underwater weighing, residual volume by helium dilution, and selected anthropometric measures. The differences between observed and predicted responses were analyzed for the five models. Four statistical tests were used to validate the equations, including tests for the mean of differences, proportion of positive differences, equality of standard errors from regression, and equivalence of regression coefficients between original and second sample data. The Michael and Katch equation and two Forsyth and Sinning equations (FS1 and FS21) for body density did not predict as well as expected. The Michael and Katch equation tends to overpredict body density while FS1 underpredicts. The FS2 equation, consisting of a constant adjustment to FS1, predicts well near the mean but not at the ends of the sample range. The two Tcheng and Tipton equations produce estimates which slightly but consistently overpredict minimum wrestling weight, the long form equation by 2.5 pounds and the short form by 3.8 pounds. As a result the proportion of positive differences is less than would be expected. But based on the tests for the standard errors and regression coefficients, the evidence does not uniformly reject these two equations.

BACKGROUND: Current medical applications for diagnostic ultrasound are numerous. The technology is attractive because of its ease of use, noninvasive nature and low cost. Recent technological advances have improved ultrasound images of spine-related soft tissues. OBJECTIVE: To examine and summarize the spine-related diagnostic ultrasound literature to help aid in understanding its possible applications. DATA SOURCES: This literature search was part of a larger search in which several hundred musculoskeletal diagnostic ultrasound articles were collected. MEDLINE from 1970 to present was searched electronically. Chiropractic Research Archives Collection (Vol. I-IV) were inspected manually. Bibliographies and references from studies obtained were examined thoroughly for additional references. DATA SYNTHESIS: All articles related to diagnostic ultrasound and its spinal applications were collected and reviewed, except those focusing on intraoperative spinal ultrasound in neurosurgery. RESULTS: Ultrasound has long been used to measure the spinal canal, detect cord abnormalities and examine soft tissue abnormalities. Recently, it has been used to quantify scoliotic curves, measure multifidus muscle size and image sciatic nerve lesions. CONCLUSION: Several well-documented applications of spine-related diagnostic ultrasound, along with many new possible applications, make this technology important to any clinician interested in noninvasive diagnostic applications for the spine and soft tissue.

This study was intended to determine if previously-developed body composition prediction equations were valid for use with a Division I university football team. A sample of 68 Division I football players with a mean age of 19.7 yr, was assessed for body density (BD) by underwater weighing (UWW), residual volume by helium dilution, and 26 selected anthropometric measures. A predicted BD was obtained by using two sets of equations developed from college football players and from three generalized equations. The differences between predicted and observed body densities were analyzed. Seven of the nine models examined failed to accurately predict the BD for this population of university football players. One sport-specific equation of White, Mayhew, and Piper for individuals in the backfield and a generalized model of Jackson and Pollock (JP) containing two circumferences performed well when considering the mean of differences and the magnitude of total error relative to the published standard error. However, both of these models overestimate body density for players with low BD and underestimate BD when actual BD is high. Using the JP model for a player whose actual BD is near the sample mean of 1.070, the estimated mean is very close at 1.069. However, for players with actual BD of 1.050, the estimated mean is 1.054, and if actual BD is 1.085, the JP estimated mean is 1.078. The bias is linear between these points.

Additional research is needed in order to document the effects of rebound training. Efforts should focus on the factors that are necessary for standardising the intensity of exercise such as step height and frequency. In addition, attention may be given to alternative methods of increasing exercise intensity while rebounding. One such method may be to increase the total muscle mass involved by adding the pumping of handheld weights to the rebounding exercise. Data from our laboratory (Bishop et al. 1986) has demonstrated that the addition of pumping 1-, 2- and 3-pound (0.45, 0.91 and 1.36 kg) handheld weights, at 2- and 3-foot (30 and 45 cm) heights, to rebounding exercise will increase the oxygen requirement from 26 to 60%. Assessing these effects in a training study would necessitate testing for adaptation in the upper extremities. This type of training highlights the need for activity specific tests. More specifically, additional research is needed to: 1. Determine the energy cost of activities other than jogging/bouncing that may be possible on a mini-trampoline, such as those described by White (1984). 2. Determine the training response of subjects in studies in which the controllable factors affecting intensity are standardised. 3. Examine the effects of longer periods of rebound training. Because rebounding exercise is novel to most subjects, it would appear that the length of training should allow subjects to maintain a reasonable frequency, intensity, and duration of exercise above that needed for familiarization with the new activity. 4. Determine if the prolonged use of other training aids (limb weights) with rebounding is feasible and effective in long term training.(ABSTRACT TRUNCATED AT 250 WORDS)

INTRODUCTION Leg length inequalities (LLI) are a common finding. Rasterstereography offers a non-invasive, contact-free and reliable method to detect the effects of LLIs on spinal posture and pelvic position. MATERIALS AND METHODS A total of 115 subjects were rasterstereographically examined during different artificially created leg length inequalities (5-15 mm) using a platform. The pelvic obliquity and torsion and the lateral and frontal deviation of the spine, as well as the surface rotation, were measured. RESULTS Changes in platform height led to an increase of the pelvic tilt and torsion. Only minor changes in the spinal posture were found by different simulated leg length inequalities. CONCLUSIONS Our study showed that there was a correlation between an artificial leg length inequality up to 15 mm and pelvic tilt or torsion, but only minor changes in the spinal posture were measured. Further studies should investigate the effects of greater leg length inequalities on spine and pelvis.

BACKGROUND: Current evidence indicates that measurement of pleural fluid N-terminal pro-brain natriuretic peptide (NT-proBNP) levels can aid in distinguishing pleural effusions of cardiac origin from those of noncardiac origin. To date only one study has described simultaneous measurement of pleural fluid brain natriuretic-32 peptide (BNP) and NT-proBNP. The purpose of the present study was to determine pleural fluid BNP and NT-proBNP levels and analyze the relationship between these two measurements. We hypothesized that there would be a positive correlation between pleural fluid NT-proBNP and BNP while NT-proBNP levels would be higher than BNP levels. METHODS: Levels of pleural fluid NT-proBNP and BNP were measured by enzyme immunoassay (EIA) in a total of 80 patients: 20 with congestive heart failure (CHF), 20 status post coronary artery bypass graft (CABG), 20 with carcinoma, and 20 with pneumonia. RESULTS: Comparison of NT-proBNP and BNP concentrations using Spearman s method of statistical analysis revealed a correlation coefficient of 0.572, p < 0.001. Evaluation of the diagnostic accuracy of BNP and NT-proBNP in patients with pleural effusions of cardiac origin demonstrated an area under the receiver operating characteristic curve (AUC) of 0.700 (95% confidence interval [CI], 0.569 to 0.831) and 0.835 (95% CI, 0.721 to 0.949), respectively. CONCLUSIONS: Though levels of pleural fluid BNP have a statistically significant correlation with those of NT-proBNP, this relationship only explains 32% of the variancein NT-proBNP levels. Furthermore, when compared to BNP, NT-proBNP is a more accurate diagnostic aid in the evaluation of pleural effusions of cardiac origin.

BACKGROUND AND PURPOSE: Few studies have been concerned with the patient's perception of the outcome of limb lengthening. We describe the psychological and social functioning after at least 2 years of follow-up in patients who had had a leg length discrepancy and who had undergone an Ilizarov limb lengthening procedure. PATIENTS AND METHODS: Self-esteem and perceived competence were measured in 37 patients (aged 17-30 years) both preoperatively and at a mean follow-up of 7 (2-14) years. At follow-up, health-related quality of life, functioning at school, daily activities, and treatment-related experiences were measured, and also retrospectively for the preoperative period. RESULTS: Preoperative and follow-up scores for self-esteem were similar. Overall perceived competence scores at follow-up were comparable to that of a healthy normal population. Patients' perceived athletic competence was lower and their perceived level of behavioral conduct was higher. At follow-up, patients had more positive appraisal of their physical appearance. Most health-related quality of life scores were not significantly different to those of the healthy normal population, apart from a reduced gross motor function, less vitality, and more pain. Patients with a remaining leg length inequality (LLI) of more than 2 cm had lower quality of life scores for gross motor function, sleep, pain, vitality, and depressive feelings. INTERPRETATION: At an average of 7 years after an Ilizarov limb lengthening procedure, patients still have physical restraints, but they appear to have normal psychosocial functioning, self-esteem, and perceived competence. These patients have quality of life scores comparable to those of norm groups, apart from a reduced gross motor function, less vitality and more pain. Residual LLI of more than 2 cm remains important even after long-term follow-up; these patients report lower quality of life.

OBJECTIVE To determine the accuracy of instrumented, prone compressive leg checking. DESIGN Point measures (n=29) on single participants. SETTING Chiropractic college research clinic. METHODS A pair of surgical boots was modified to permit continuous measurement of leg length inequality (LLI). The accuracy of prone leg checking for a masked examiner (n = 29) was determined, against the gold standard of artificial LLI that was created by randomly inserting zero to six 1.6 mm shims in either boot. Accuracy was defined as the examiner's ability to correctly assess the change in the number and side of shims inserted, in two consecutive observations per participant. Linear regression and Bland-Altman statistics were obtained to determine the concurrent validity of compressive leg checking compared to a reference standard. RESULTS The observed and artificial LLI shared 86% of their variation (n = 29) The mean examiner error was 2.7 mm and the accuracy of dichotomous short leg determination for two shim insertions was 86.2%. The 95% confidence interval for the Bland-Altman limits-of-agreement for observed vs. artificial change in LLI was (-7.6,+5.2). CONCLUSIONS Instrumented, compressive leg checking seems highly accurate, detecting artificial changes in leg length of 2-3 mm, and thus possesses concurrent validity assessed against artificial LLI. Pre- and post leg check differences should exceed about 4-6 mm to be highly confident a real change has occurred. It is unknown whether compressive leg checking is clinically relevant.

ABSTRACT: BACKGROUND: In a previous Swedish study it was shown that it is possible to predict which chiropractic patients with persistent LBP will not report definite improvement early in the course of treatment, namely those with LBP for altogether at least 30 days in the past year, who had leg pain, and who did not report definite general improvement by the second treatment. The objectives of this study were to investigate if the predictive value of this set of variables could be reproduced among chiropractic patients in Finland, and if the model could be improved by adding some new potential predictor variables. METHOD: The study was a multi-centre prospective outcome study with internal control groups, carried out in private chiropractic practices in Finland. Chiropractors collected data at the 1st, 2nd and 4th visits using standardized questionnaires on new patients with LBP and/or radiating leg pain. Status at base-line was identified in relation to pain and disability, at the 2nd visit in relation to disability, and "definitely better" at the 4th visit in relation to a global assessment. The Swedish questionnaire was used including three new questions on general health, pain in other parts of the spine, and body mass index. RESULTS: The Swedish model was reproduced in this study sample. An alternative model including leg pain (yes/no), improvement at 2nd visit (yes/no) and BMI (underweight/normal/overweight or obese) was also identified with similar predictive values. Common throughout the testing of various models was that improvement at the 2nd visit had an odds ratio of approximately 5. Additional analyses revealed a dose-response in that 84% of those patients who fulfilled none of these (bad) criteria were classified as "definitely better" at the 4th visit, vs. 75%, 60% and 34% of those who fulfilled 1, 2 or all 3 of the criteria, respectively. CONCLUSION: When treating patients with LBP, at the first visits, the treatment strategy should be different for overweight/obese patients with leg pain as it should be for all patients who fail to improve by the 2nd visit. The number of predictors is also important.

The Pictorial Representation of Illness and Self Measure (PRISM) assesses suffering. In this article, the authors explored the feasibility and psychometric qualities of 2 revised versions of the PRISM-PRISM-R1 and PRISM-R2-that they used in 3 studies of participants with different medical problems. The results showed significant differences between the patient groups in suffering as measured with the revised PRISMs. In addition, the revised PRISMs appeared to be sensitive to change in the predicted direction after an intervention. Last, the 2 measures of the revised PRISM seemed to indicate different aspects of suffering. These findings yield preliminary support for the feasibility and validity of the PRISM-R2.

Objectives: To determine whether a correlation between motion palpation findings and abnormal coupling patterns, as viewed in lumbar functional X-rays, can be demonstrated in low back pain (LBP) patients.Design: A prospective observational study of patients who present to a chiropractic clinic for assessment of low back pain.Subjects: The sample population consisted of 27 consecutive patients presenting with LBP between the ages of 20-50 year old and who were capable of pain free lateral lumbar flexion.Intervention: All subjects underwent motion palpation to determine whether a "fixation" at the L4/5 existed. All had lumbar spine X-rays in an anterior-posterior (AP) and bilateral AP lateral flexion position. X-rays were then analyzed to determine whether the coupling pattern at L4/5 was considered abnormal.Results: In those patients with a perceived L4/5 motion restriction no coupling patterns where found in 6 cases (22.4%) and normal coupling patterns in 13 cases (48%). In those patients who presented with LBP and no motion findings at L4/5 no coupling was observed in 4 cases (14.8%) and normal coupling in another 4 cases (14.8%). The chi-squared test demonstrated no statistical differences (p>0.05) between the motion fixation at L4/5 and coupling patterns from lateral flexion X-rays.Conclusion: It is of particular interest to note that the presence of the L4/5 fixation was not associated with abnormal coupling but conversely was frequently observed to be associated with normal coupling patterns. A simple correlation between a single motion palpation finding of a restriction at a L4/5 facet and an alteration in coupling patterns could not be supported.

STUDY DESIGN Original study. OBJECTIVE To compare the accuracy of radiograph (XR) estimates of lumbar total disc arthroplasty placement with high-resolution computed tomography (CT). SUMMARY OF BACKGROUND DATA Most lumbar disc arthroplasties are inserted and subsequently analyzed using anteroposterior and lateral XR: XR estimates are often correlated with clinical outcomes. No study has hitherto assessed the relative accuracy of XR estimates with CT. METHODS Patients (N = 36) had recently undergone uncomplicated lumbar total disc arthroplasty for unresponsive discogenic back pain. Interpedicular midline malplacement and vertebral body penetration (VBP) were estimated after surgery, by "blinded" independent review, using computer software on both nonrotated XR and high-resolution CT at the same clinic attendance. RESULTS Results were obtained in N = 36 patients. No significant differences were found between XR and CT in the mean +/- standard error estimation of either midline malplacement (1.7 +/- 0.2 mm vs. 1.8 +/- 0.2 mm, P = 0.86) or VBP (1.5 +/- 0.3 mm vs. 1.6 +/- 0.3 mm, P = 0.79). However, the correlation between XR and CT for midline malplacement appeared strong (r = 0.72, P < 0.001), whereas the correlation between XR and CT for VBP was poor (r = 0.23 P > 0.10). The standard deviation of XR-CT differences for VBP (2.2 mm) was almost twice that for midline malplacement (1.2 mm). XR-CT differences exceeded the 95% limit of agreement in 6% of midline placement estimates, and in 8% for VBP. CONCLUSION Nonrotated XR permitted an accurate and valid estimate of midline malplacement relative to CT in most cases. However, the correlation was biased toward XR underestimation of CT-derived malplacement, and highly significant XR-CT differences occurred in 6% of estimates: early postoperative CT is therefore recommended to enhance the estimation of midline placement. XR-CT agreement for VBP was poor: CT is therefore indicated in all cases for this parameter. This is the first study to compare the accuracy of XR in estimating lumbar total disc arthroplasty placement with CT.

STUDY DESIGN Preassessment and postassessment of treatment intervention. OBJECTIVE To determine the changes in pain and disability secondary to shoe lift intervention for subjects with chronic low back pain (LBP) who have a limb length inequality (LLI). BACKGROUND Previous reports have suggested that LLI may be a cause of LBP Most prior studies of lift therapy for management of LLI in patients with LBP have lacked clear guidelines for clinicians regarding the implementation of shoe lift intervention. METHODS AND MEASURES Twelve subjects (6 male, 6 female) between the ages of 19 and 62 years with LLI (6.4-22.2 mm) and chronic LBP (1-30 years) participated. Visual analog scale pain ratings and disability questionnaire scores were acquired before and after lift intervention. Subjects determined their lift height based on resolution of LBP symptoms. RESULTS Subjects experienced relief of general pain symptoms (P =.0006) and pain associated with standing (P=.002) following lift intervention, with minimally clinically important (MCID) reductions in general pain for 9 of 12 subjects and MCID reductions in standing pain for 8 of 10 subjects. Subjects also had less disability on the disability questionnaire (P =.001) following the intervention, with 9 of 12 subjects experiencing MCID reductions in disability. CONCLUSION Shoe lifts may reduce LBP and improve function for patients who have chronic LBP and an LLI. Randomized controlled trials are needed to assess the efficacy of this intervention.

The McKenzie treatment model advocates extension-based treatments for sub-groups of low back pain (LBP) patients and an improvement in extension range is seen as a positive outcome. The treatment model states that patients who fit the McKenzie derangement classification respond faster than other patients. The validity of this treatment model and of the clinical measures of extension has not yet been established. Fifty patients with LBP were classified as derangement (n=40) or non-derangement (n=10) based on a McKenzie assessment and then treated with extension procedures. Lumbar extension was measured in two positions, standing and prone, with three methods, inclinometer, Schober and finger tip to floor, on Day 1 and Day 5 of treatment. Patients completed a global perceived effect (GPE) scale on Day 5. Construct validity was tested, by comparing extension improvement and the GPE scores between the two groups. Responsiveness of the six extension measures was calculated. All patients gained extension range however the derangement group had significantly higher GPE scores and greater improvement in extension range. The modified Schober method in standing was the most responsive method for measuring lumbar extension. The results of this study support the measurement of lumbar extension, for patients, treated with extension procedures and provides evidence for the construct validity of one aspect of the McKenzie treatment model. The modified Schober method is the preferred protocol for a clinical setting.