The Reliability of Sensor-Assisted Soft Tissue Measurements in Primary Total Knee Arthroplasty.

BACKGROUND: In pursuit to improve soft tissue balancing in total knee arthroplasties (TKAs), a wireless device was introduced to assess femorotibial pressures. The aim of this study was to evaluate the reliability of this device. METHODS: After 33 TKAs were balanced by conventional techniques, contact pressures were measured using a wireless sensor 3 times in a row; twice while the examiner was blinded for the result (n = 29); and once while the examiner was able to see the result as visual feedback (n = 32). Femorotibial pressures were measured in the medial and lateral compartments with the knee in 10°, 45°, and 90° of flexion (6 measurements per TKA). Furthermore, both the combined pressure and the difference in pressure between the compartments was calculated throughout the 3 positions (together another 6 measurements per TKA). RESULTS: The intraclass correlation coefficient between the blind measurements was poor in 2 of the 12 (17%), moderate in 4 of 12 (33%), and good in 6 of 12 (50%) measurements. The intraclass correlation coefficient between the blind and observing measurement was poor in 2 of the 12 (17%), moderate in 6 of 12 (50%), and good in 4 of 12 (33%) measurements. Especially measurements in 10° of flexion are associated with poorer reliability. CONCLUSION: The wireless sensor has a moderate to good reliability in 83% of the measurements.

Medium term effects of including manual therapy in a pulmonary rehabilitation program for chronic obstructive pulmonary disease (COPD): a randomized controlled pilot trial.

STUDY DESIGN: Randomized clinical trial. OBJECTIVE: To investigate the effect of including manual therapy (MT) in a pulmonary rehabilitation program for patients with chronic obstructive pulmonary disease (COPD). BACKGROUND: The primary source of exercise limitation in people with COPD is dyspnea. The dyspnea is partly caused by changes in chest wall mechanics, with an increase in chest wall rigidity (CWR) contributing to a decrease in lung function. As MT is known to increase joint mobility, administering MT to people with COPD carries with it the potential to influence CWR and lung function. METHODS: Thirty-three participants with COPD, aged between 55 and 70 years (mean = 65·5±4 years), were randomly assigned to three groups: pulmonary rehabilitation (PR) only, soft tissue therapy (ST) and PR, and ST, spinal manipulative therapy (SM), and PR. Outcome measures including forced expiratory volume in the 1st second (FEV1), forced vital capacity (FVC), 6-minute walking test (6MWT), St. George's respiratory questionnaire (SGRQ), and the hospital anxiety and depression (HAD) scale were recorded at 0, 8, 16, and 24 weeks. RESULTS: There was a significant difference in FVC between the three groups at 24 weeks (P = 0·04). For the ST+SM+PR group versus PR only the increase was 0·40 l (CI: 0·02, 0·79; P = 0·03). No major or moderate adverse events (AE) were reported following the administration of 131 ST and 272 SM interventions. DISCUSSION: The increase in FVC is a unique finding. Although the underlying mechanisms responsible for this outcome are not yet understood, the most likely explanation is the synergistic effect resulting from the combination of interventions. These results support the call for a larger clinical trial in the use of MT for COPD.

Short-term effects of a course of manual therapy and exercise in people with moderate chronic obstructive pulmonary disease: a preliminary clinical trial.

OBJECTIVE: The purpose of this preliminary study was to demonstrate the feasibility of a study that measures the short-term effects of a course of manual therapy (MT) and exercise (Ex) in people with moderate chronic obstructive pulmonary disease (COPD). METHODS: Fifteen participants (9 males; mean age, 56.1 years), with moderate COPD (mean % predicted forced expiratory volume in the first second [FEV1% predicted], 61.8%), were randomly allocated to 1 of 3 groups: soft tissue therapy only (ST); ST and spinal manipulation (SM); or ST, SM, and Ex. The intervention continued for 4 weeks. Outcome measures included FEV1, forced vital capacity (FVC), chronic respiratory questionnaire (CRQ-SAS) scores, distance walked in a 6-minute walking test, and monitoring for adverse events. RESULTS: There was an increase in FVC for the SM + ST + Ex group compared with ST only and ST + SM (1.01 and 1.00 L, respectively). Distance walked increased in the ST + SM and ST + SM + Ex groups compared with ST only (120.0 and 168.0 m, respectively). Dyspnea levels decreased in the ST + SM and ST + SM + Ex groups compared with ST only (0.64 and 0.44, respectively). There were no major or moderate adverse events reported following ST or SM interventions. CONCLUSIONS: For this small group of patients, combining MT with Ex produced short improvements in FVC, distance walked, and dyspnea levels, with no major or moderate adverse events. This preliminary study showed that a larger study evaluating the clinical outcomes of MT for people with moderate COPD appears feasible.

Multilevel latent variable models for global health-related quality of life assessment.

Quality of life (QOL) assessment is a key component of many clinical studies and frequently requires the use of single global summary measures that capture the overall balance of findings from a potentially wide-ranging assessment of QOL issues. We propose and evaluate an irregular multilevel latent variable model suitable for use as a global summary tool for health-related QOL assessments. The proposed model is a multiple indicator and multiple cause style of model with a two-level latent variable structure. We approach the modeling from a general multilevel modeling perspective, using a combination of random and nonrandom cluster types to accommodate the mixture of issues commonly evaluated in health-related QOL assessments--overall perceptions of QOL and health, along with specific psychological, physical, social, and functional issues. Using clinical trial data, we evaluate the merits and application of this approach in detail, both for mean global QOL and for change from baseline. We show that the proposed model generally performs well in comparing global patterns of treatment effect and provides more precise and reliable estimates than several common alternatives such as selecting from or averaging observed global item measures. A variety of computational methods could be used for estimation. We derived a closed-form expression for the marginal likelihood that can be used to obtain maximum likelihood parameter estimates when normality assumptions are reasonable. Our approach is useful for QOL evaluations aimed at pharmacoeconomic or individual clinical decision making and in obtaining summary QOL measures for use in quality-adjusted survival analyses.

Is premigration health screening for tuberculosis worthwhile?

OBJECTIVE: To determine whether premigration screening for tuberculosis is worth undertaking in visa applicants, and whether screening resources are being appropriately directed towards intending migrants at highest risk of tuberculosis. DESIGN, SETTING AND PARTICIPANTS: A 12-month survey of all intending migrants with tuberculosis necessitating treatment detected during the premigration health assessment process, whose medical examinations were submitted to the Department of Immigration and Citizenship's Global Health Branch for assessment by a Medical Officer of the Commonwealth between 1 July 2009 and 30 June 2010. MAIN OUTCOME MEASURES: Individuals diagnosed with active tuberculosis; proportions diagnosed by sputum smear and culture tests or clinically, and with susceptibility test results; distribution of visa types among people diagnosed. RESULTS: In premigration assessments, 519 people were diagnosed with active tuberculosis (prevalence, 137 per 100,000 in examined population). The top source countries for people with tuberculosis were the Philippines (21.8%), India (16.8%), Vietnam (16.2%) and China (8.3%). Positive sputum smear test results were submitted for 67 cases (12.9%). Positive culture test results were obtained in 230 cases (44.3%), but only 95 of these (41.3%) had susceptibility test results, with 83 fully susceptible. Four people had multidrug-resistant tuberculosis (prevalence, 1.06 per 100 000 population). Five people had both active tuberculosis and HIV infection. Of all those diagnosed with tuberculosis, 162 (31.2%) were intending students, 82 (15.8%) were intending visitors, and 53 (10.2%) were applicants for humanitarian (refugee and Special Humanitarian Program) visas. CONCLUSIONS: Premigration health screening of intending migrants is identifying substantial numbers of people who would have required treatment for tuberculosis after arrival in Australia. The high proportion of students, visitors and refugee and humanitarian entrants with tuberculosis validates the current screening program. The screening is of benefit to the applicants, whose tuberculosis is treated earlier than it otherwise would have been, and to the Australian population, by averting exposure to people with active tuberculosis.

The Emotional Dysregulation Questionnaire: Development and comparative analysis.

OBJECTIVES: A widely used measure of emotion dysregulation, the Difficulties in Emotion Regulation Scale (DERS), may insufficiently cover a number of potentially important aspects of emotional dysregulation. A new measure of emotional dysregulation, the Emotional Dysregulation Questionnaire (EDQ) was therefore developed based upon an eight-factor model of the construct. DESIGN AND METHOD: The DERS and the EDQ were administered to a community sample (N = 362; 183 female, 179 male), along with a number of measures of psychopathology associated with emotional dysregulation. The capacity of the EDQ and the DERS to account for the emotional dysregulation associated with these different types of psychopathology was then compared. RESULTS: In several of the psychopathologies examined, the EDQ could account for more variation than the DERS, suggesting that it more comprehensively assessed the emotion regulation deficits associated with these issues. CONCLUSIONS: Results suggest the EDQ possesses several advantages relative to the DERS, allowing for a more comprehensive and accurate assessment of emotional dysregulation. PRACTITIONER POINTS: Emotional dysregulation is a common component of many psychological disorders. The Difficulties in Emotion Regulation Scale is one of the primary self-report measures used to asses these difficulties, however, concerns exist that it may not comprehensively assess the construct of emotional dysregulation. A new self-report measure of comparable length, the Emotional Dysregulation Questionnaire has been developed, with this new measure possessing several advantages relative to the DERS with regard to the assessment of emotional dysregulation. The use of this measure in clinical practice may more accurately identify the emotion regulation deficits present in clients.

Volume not number of metastases: Gamma Knife radiosurgery management of intracranial lesions from an Australian perspective.

BACKGROUND AND PURPOSE: To assess the response of the first cohort of patients treated with Gamma Knife radiosurgery in Australia. MATERIALS AND METHODS: A prospectively collected cohort of 180 patients with intracranial metastases from different primaries was treated between August 2010 and July 2017. Survival was calculated using the Kaplan-Meier's method. Cox regression was used for multivariate analysis. RESULTS: Currently 141 patients (78.3%) have died of their disease. The median survival for the group as a whole was 9.2 months, with observed differences resulting from the volume of tumor burden (11.4 months for volumes <3.2 cm3 to 5.16 months for volume >9.1 cm3). Overall 2-year survival was 20.7%. CONCLUSION: Results from the first Gamma Knife radiosurgery center in Australia showed that the treatment is feasible and effective, consistent with the international experience. For patients with larger numbers of intracranial metastases, the total volume of the intracranial burden may be of more significance in predicting outcomes. While there appeared to be a difference in survival by histologic origin, this could be related to concurrent systemic immunotherapy available for certain tumors.

A finite mixture method for outlier detection and robustness in meta-analysis.

When performing a meta-analysis unexplained variation above that predicted by within study variation is usually modeled by a random effect. However, in some cases, this is not sufficient to explain all the variation because of outlier or unusual studies. A previously described method is to define an outlier as a study requiring a higher random effects variance and testing each study sequentially. An extension is described where the studies are considered to be a finite mixture of outliers and non-outliers, allowing any number of outlier studies and the use of standard mixture model techniques. The bootstrap likelihood ratio test is used to determine if there are any outliers present by comparing models with and without outliers, and the outlier studies are identified using posterior predicted probabilities. The estimation of the overall treatment effect is then determined including all observations but with the outliers down-weighted. This has the advantage that studies that are marginal outliers are still included in the meta-analysis but with an appropriate weighting. The method is applied to examples from meta-analysis and meta-regression.

Associations between hearing impairment and mortality risk in older persons: the Blue Mountains Hearing Study.

PURPOSE: To assess whether hearing loss predicts an increased risk of mortality. METHODS: The Blue Mountains Hearing Study examined 2956 persons (49+ years) during 1997 to 2000. The Australian National Death Index was used to identify deaths until 2005. Hearing loss was defined as the pure-tone average (0.5-4 kHz) of air-conduction hearing thresholds greater than 25 dB HL. Associations between hearing loss and mortality risk were estimated using Cox regression and structural equation modeling (SEM). RESULTS: When we used Cox regression, we discovered that hearing loss was associated with increased risk of cardiovascular (hazard ratio [HR] 1.36, 95% confidence interval [CI] 1.08-1.84) and all-cause (AC) mortality (HR 1.39, 95% CI 1.11-1.79) after adjustment for age and sex but not after multivariable adjustment. SEM pathway analysis, however, revealed a greater AC mortality risk (HR 2.58, 95% CI 1.64-4.05) in persons with hearing loss, which was mediated: cognitive impairment (HR 1.45, 95% CI 1.08-1.94) and walking disability (HR 1.63, 95% CI 1.24-2.15). These variables increased mortality both directly and indirectly through effects on self-rated health. CONCLUSIONS: Hearing loss was associated with increased AC mortality via three mediating variables: disability in walking, cognitive impairment, and self-rated health. It is important to recognize that persons with combined disabilities are at increased risk of cardiovascular and AC mortality.

Direct and indirect effects of visual impairment on mortality risk in older persons.

OBJECTIVE: To investigate pathways from visual impairment to increased all-cause mortality in older persons. METHODS: The Blue Mountains Eye Study examined 3654 persons 49 years and older (82.4% response) during 1992-1994 and after 5 and 10 years. Australian National Death Index data confirmed deaths until 2005. Visual impairment was defined as presenting, correctable, and noncorrectable, using better-eye visual acuity. Associations between visual impairment and mortality risk were estimated using Cox regression and structural equation modeling. RESULTS: After 13 years, 1273 participants had died. Adjusting for mortality risk markers, higher mortality was associated with noncorrectable visual impairment (hazard ratio [HR], 1.35; 95% confidence interval [CI], 1.04-1.75). This association was stronger for ages younger than 75 years (HR, 2.58; 95% CI, 1.42-4.69). Structural equation modeling revealed greater effects of noncorrectable visual impairment on mortality risk (HR, 5.25; 95% CI, 1.97-14.01 for baseline ages <75 years), with both direct (HR, 2.16; 95% CI, 1.11-4.23) and indirect (HR, 2.43; 95% CI, 1.17-5.03) effects. Of mortality risk markers examined, only disability in walking demonstrated a significant indirect pathway for the link between visual impairment and mortality. CONCLUSIONS: Visual impairment predicted mortality by both direct and indirect pathways, particularly for persons younger than 75 years with noncorrectable visual impairment. Disability in walking, which can substantially influence general health, represented a major indirect pathway.

Infant growth modelling using a shape invariant model with random effects.

Models for infant growth have usually been based on parametric forms, commonly an exponential or similar model, which have been shown to fit poorly especially during the first year of life. An alternative approach is to use a non-parametric model, based on a shape invariant model (SIM), where a single function is transformed by shifting and scaling to fit each subject. In the model a regression spline is used as the function, with log transformation of the data and a simplification of the SIM, obtained from the relationship with the exponential model. All subjects are fitted as a nonlinear mixed effects model, allowing the variation in the parameters between subjects to be determined. Methods for the inclusion of covariates in growth models based on SIM are developed, with parameters for time independent covariates included in the model by varying either the shape, the size parameter or the growth parameter and time-dependent co-variates included by transforming the time axis, to either increase or decrease the growth rate dependent on the co-variate, similar to methods used for accelerated failure-time models. The model is used to fit weight data for 602 infants, measured from 0 to 2 years as part of the Childhood Asthma Prevention Study (CAPS) trial, and to determine the effect of breastfeeding on infant weight.