Biomedical subjects

R Wolfe

Publications and source records attributed to R Wolfe.

At least 19 recordsLinked to original sources

PubMed2006

Foot rotation--a potential target to modify the knee adduction moment.

Isolating the particular joints/limb segments associated with knee adductor moment variability may provide clinically important data that could help to identify strategies to reduce medial tibiofemoral joint load. The aim of this study was to examine whether or not foot and thigh rotation during human locomotion are significant determinants of knee adductor moment variability. Three-dimensional gait analyses were performed on 32 healthy adult women (mean age 54+/-12 years, mean BMI 25+/-4 kg m(-2)) with radiologically normal knees. The relationships between foot rotation, thigh rotation and the external knee adduction moment were examined during early and late-stance phases of the gait cycle. The degree of foot rotation correlated significantly with the magnitude of the peak knee adduction moment during late stance (r=0.40, p=0.024). No significant associations were apparent between thigh rotation and the peak knee adduction moment. The association between foot rotation and the knee adduction moment in this study suggests that women who walk with external rotation at the foot reduce their knee adduction moment during late stance. This result implies that changes in foot kinematics can modify the medial tibiofemoral load during gait, which may be important in the prevention and management of knee osteoarthritis.

Adult↗

PubMed2006

Clinician agreement on gait pattern ratings in children with spastic hemiplegia.

The level of agreement between clinicians' ratings of gait patterns in children with spastic hemiplegia was investigated using the Winters, Gage, and Hicks (WGH) classification scale. Sixteen clinicians (nine physiotherapists, seven orthopaedic surgeons) from six gait laboratories in five different countries rated gait patterns in 34 children with spastic hemiplegia (22 males, 12 females; mean age 10y [SD 3y], range 6-18y). Archived three-dimensional gait reports (kinematic and video data) and videos (video clips only) were rated for each child. Agreement between clinicians was substantial for reports (weighted kappa [wkappa] 0.77, range 0.62-0.89). Agreement was lower for videos (wkappa 0.63, range 0.39-0.97) and for clinicians' agreement between reports and corresponding videos (wkappa 0.62, range 0.47-0.76). Exact agreement was unacceptable for some gait patterns using reports (mean 65%, range 32-74%) and videos (mean 53%, range 35-94%). Not all gait patterns could be rated using the original WGH categories. It was concluded that: (1) agreement is acceptable using the WGH tool; (2) kinematic data from 3D instrumented gait analysis and video should be used together when using the WGH scale; and (3) further refinement of this classification is required.

Adolescent↗

PubMed2006

Lengthening and transfer of hamstrings for a flexion deformity of the knee in children with bilateral cerebral palsy: technique and preliminary results.

Between July 2000 and April 2004, 19 patients with bilateral spastic cerebral palsy who required an assistive device to walk had combined lengthening-transfer of the medial hamstrings as part of multilevel surgery. A standardised physical examination, measurement of the Functional Mobility Scale score and video or instrumented gait analysis were performed pre- and post-operatively. Static parameters (popliteal angle, flexion deformity of the knee) and sagittal knee kinematic parameters (knee flexion at initial contact, minimum knee flexion during stance, mean knee flexion during stance) were recorded. The mean length of follow-up was 25 months (14 to 45). Statistically significant improvements in static and dynamic outcome parameters were found, corresponding to improvements in gait and functional mobility as determined by the Functional Mobility Scale. Mild hyperextension of the knee during gait developed in two patients and was controlled by adjustment of their ankle-foot orthosis. Residual flexion deformity > 10 degrees occurred in both knees of one patient and was treated by anterior distal femoral physeal stapling. Two children also showed an improvement of one level in the Gross Motor Function Classification System.

Adolescent↗

PubMed2006

Correction of severe crouch gait in patients with spastic diplegia with use of multilevel orthopaedic surgery.

BACKGROUND: Severe crouch gait in patients with spastic diplegia causes excessive loading of the patellofemoral joint and may result in anterior knee pain, gait deterioration, and progressive loss of function. Multilevel orthopaedic surgery has been used to correct severe crouch gait, but no cohort studies or long-term results have been reported, to our knowledge. METHODS: In order to be eligible for the present retrospective cohort study, a patient had to have a severe crouch gait, as defined by sagittal plane kinematic data, that had been treated with multilevel orthopaedic surgery as well as a complete clinical, radiographic, and instrumented gait analysis assessment. The surgical intervention consisted of lengthening of contracted muscle-tendon units and correction of osseous deformities, followed by the use of ground-reaction ankle-foot orthoses until stable biomechanical realignment of the lower limbs during gait was achieved. Outcome at one and five years after surgery was determined with use of selected sagittal plane kinematic and kinetic parameters and valid and reliable scales of functional mobility. Knee pain was recorded with use of a Likert scale, and all patients had radiographic examination of the knees. RESULTS: Ten subjects with severe crouch gait and a mean age of 12.0 years at the time of surgery were studied. After surgery, the patients walked in a more extended posture, with increased extension at the hip and knee and reduced dorsiflexion at the ankle. Pelvic tilt increased, and normalized walking speed was unaltered. Knee pain was diminished, and patellar fractures and avulsion injuries healed. Improvements in functional mobility were found, and, at the time of the five-year follow-up, fewer patients required the use of wheelchairs or crutches in the community than had been the case prior to intervention. CONCLUSIONS: Multilevel orthopaedic surgery for older children and adolescents with severe crouch gait is effective for relieving stress on the knee extensor mechanism, reducing knee pain, and improving function and independence.

Adolescent↗

PubMed2005

Clinical, laboratory and genetic markers associated with erosions and remission in patients with early inflammatory arthritis: a prospective cohort study.

We investigated the relationship between clinical, laboratory and genetic markers and outcome measures in 159 patients with recent onset of inflammatory arthritis (IA). The majority of patients were managed in community-based rheumatology practice. Median duration of arthritis at baseline was 3 months with median follow-up of 4.0 years (range 0-10). Markers of disease activity and 1987 ACR criteria for rheumatoid arthritis (RA) were estimated every 6 months for the first 2 years and annually thereafter. Presence of shared epitopes (SE) was established by PCR-based method. Main outcome variables were attainment of remission and presence of erosions on X-rays of hands and feet at 3 years. Remission was seen in 34.3% of patients and was independently related to age 60 and older (odds ratio (OR) 3.2; 95% confidence interval (CI), 1.2-8.7) and inversely to the presence of rheumatoid factor (RF) (OR 8.3; 95% CI, 3.2-21.3 for persistent arthritis). Patients with two SE were likely to have persistent arthritis (P=0.006), but this was not significant when corrected for RF. Independent predictors for erosions at 3 years were RF (OR 7.5; 95% CI, 1.9-29.5) and area under the curve for number of swollen joints (OR 1.08; 95% CI, 1.02-1.16). SE status was not predictive of erosions at 3 years (OR 1.6; 95% CI, 0.7-3.7). In univariate analysis, patients possessing DERAA motif on DRB1 were less likely to have erosive disease than without this motif at 4 years (OR 0.21; 95% CI, 0.0-0.9, P=0.037) but this finding was partly explained by adjusting for RF (adjusted OR 0.24; 95% CI 0.04-1.37). In this study of recent onset IA, active disease and RF were associated with poor outcome. Whilst SE did not predict erosive disease, patients with DERAA motif may be protected against erosions whilst the presence of two SE alleles suggests persistence of arthritis.

Age of Onset↗

PubMed2005

The effectiveness of a squash eyewear promotion strategy.

OBJECTIVE: To evaluate the protective eyewear promotion (PEP) project, which was a comprehensive educational strategy to increase the use of appropriate protective eyewear by squash players. METHODS: An ecological study design was used. Four squash venues in one playing association were randomly chosen to receive PEP and four in another association maintained usual practice and hence formed a control group. The primary evaluation measurements were surveys of cross sectional samples of players carried out before and after the intervention. The surveys investigated players' knowledge, behaviours, and attitudes associated with the use of protective eyewear. The survey carried out after the intervention also determined players' exposure to PEP. Univariate and multivariate analyses were undertaken to describe differences at PEP venues from pre- to post-intervention and to compare these with the control venues. RESULTS: The PEP players had 2.4 times the odds (95% confidence interval, 1.3 to 4.2) of wearing appropriate eyewear compared with control group players post-intervention, relative to the groups' pre-intervention baselines. Components of PEP, such as stickers and posters and the availability and prominent positioning of the project eyewear, were found to contribute to players adopting favourable eyewear behaviours. CONCLUSIONS: Components of the PEP intervention were shown to be effective. The true success will be the sustainability and dissemination of the project, favourable eyewear behaviours, and evidence of the prevention of eye injuries long into the future.

Adult↗

PubMed2005

Should football players wear custom fitted mouthguards? Results from a group randomised controlled trial.

OBJECTIVE: Head/orofacial (H/O) injuries are common in Australian rules football. Mouthguards are widely promoted to prevent these injuries, in spite of the lack of formal evidence for their effectiveness. DESIGN: The Australian football injury prevention project was a cluster randomized controlled trial to evaluate the effectiveness of mouthguards for preventing H/O injuries in these players. SETTING AND SUBJECTS: Twenty three teams (301 players) were recruited from the largest community football league in Australia. INTERVENTION: Teams were randomly allocated to either the MG: custom made mouthguard or C: control (usual mouthguard behaviours) study arm. MAIN OUTCOME MEASURES: All injuries, participation in training and games, and mouthguard use were monitored over the 2001 playing season. Injury rates were calculated as the number of injuries per 1000 person hours of playing time. Adjusted incidence rate ratios were obtained from Poisson regression models. RESULTS: Players in both study arms wore mouthguards, though it is unlikely that many controls wore custom made ones. Wearing rates were higher during games than training. The overall rate of H/O injury was 2.7 injuries per 1000 exposure hours. The rate of H/O injury was higher during games than training. The adjusted H/O injury incidence rate ratio was 0.56 (95% CI 0.32 to 0.97) for MG versus C during games and training, combined. CONCLUSIONS: There was a significant protective effect of custom made mouthguards, relative to usual mouthguard use, during games. However, the control players still wore mouthguards throughout the majority of games and this could have diluted the effect.

Adolescent↗

PubMed2005

Minimizing bias in a case-control study of farm injury.

We report on our strategies to minimize bias in the FIRM study, a prospective case-control study of risk factors for serious farmwork-related injury. The study base is adult males working on farms in the catchment regions of 14 larger regional hospitals in one Australian state. Cases are identified on presentation to the emergency departments, while age-matched controls are recruited via random telephone survey. Eligibility criteria for cases include a maximum abbreviated injury severity score of at least 2, to minimize the potential for selection bias against those with less severe injuries treated outside the hospital system. An audit at one hospital showed that 93% of eligible patients identified in the electronic surveillance system had been approached regarding participation. Results to date show that 38% of those approached decline to have their contact details made available to researchers. Those who decline are asked to complete two key questions to enable comparison with those who participate. Control recruitment relies on telephoning regional households until an individual from the study base, satisfying the matching criteria, is identified. This process minimizes the potential for selecting against farm workers who may live off-farm. Ninety-four percent of age-matched eligible controls have participated to date. We are testing a dynamic pool of individuals identified as study base members but not matched on the first call to determine its effect on the probabilities of selection. Our strategies appear to be minimizing detection, selection, and response bias, thereby enhancing the validity of the study results.

Agricultural Workers' Diseases↗

PubMed2004

Risk factors for acquisition of methicillin-resistant Staphylococcus aureus (MRSA) by trauma patients in the intensive care unit.

In a previous study in the intensive care unit (ICU) of the Alfred Hospital, Melbourne, Australia, it was demonstrated that trauma patients were at particular risk of becoming colonized by methicillin-resistant Staphylococcus aureus (MRSA). We examined risk factors for MRSA acquisition in these patients using a cohort study comparing the 31 patients who acquired MRSA with 65 who did not. Data collected included ICU length of stay (LOS), mechanism of trauma, site of injury, type of surgery, trauma severity and antibiotic usage. Odds ratios (OR) were determined and adjusted for LOS. LOS in the ICU was a significant univariate predictor of MRSA acquisition (OR 13.7). When adjusted for LOS, mechanism of trauma (OR 10.4), laparotomy (OR 6.3) and administration of ticarcillin/clavulanic acid (OR 4.5) or glycopeptides (OR 5.9) remained significant. We confirmed our previous finding that LOS was associated with MRSA acquisition. Receipt of antibiotics correlated with reported literature. Novel associations were road trauma as a mechanism and laparotomy.

Accidents, Traffic↗

PubMed2004

Communicating the uncertainty in research findings: confidence intervals.

Confidence intervals (CIs) are an effective means of quantifying the uncertainty inherent in study results. Alongside considerations of possible sources of bias in the study design, CIs describe the extent to which study results are applicable in general, beyond the participants involved in the study. We discuss CI use and interpretation for some commonly encountered study designs. We highlight a close relation between CIs and p-values, such that presentation of 95% CIs can make it redundant to state whether a corresponding p-value is less than 0.05. We encourage researchers to use CIs to present their research findings, rather than relying on p-values alone.

Biomedical Research↗

PubMed2004

Dietary intake and domestic food preparation and handling as risk factors for gastroenteritis: a case-control study.

Cases of gastroenteritis were examined to identify if dietary intake prior to an episode and food-handling and storage practices in the home were risk factors for illness. Cases and controls completed a dietary questionnaire after an event or when well, and questionnaires concerning food-handling, storage and general food-hygiene practices. Comparing cases to themselves when well. subjects were more likely to have eaten cold sliced salami, fried rice and foods cooked elsewhere, and to have had a baby in nappies in the house (OR 1.52-6.24, P< or =0.01). Cases compared to non-cases were more likely to have bought frozen poultry, have eaten foods cooked elsewhere and to have had a baby in nappies in the house (OR 1.44-2.05, P< or = 001). Although food-handling and storage practices are considered important, we were unable to detect an association in this study.

Adolescent↗

PubMed2004

A randomised comparison of resuscitation with an anaesthetic rebreathing circuit or an infant ventilator in very preterm infants.

Twenty four preterm infants (< 27 weeks gestation) were randomised to resuscitation with an anaesthetic rebreathing circuit or a ventilator with volume guarantee. There was no difference in weight or gestation between the groups. End expiratory pressures were higher and less variable with the ventilator. This pilot study shows that very preterm infants can be safely and effectively resuscitated using a ventilator.

Anesthesiology↗

PubMed2004

Tibial cartilage volume change in healthy postmenopausal women: a longitudinal study.

OBJECTIVE: To determine whether the amount of joint cartilage in healthy postmenopausal women is stable or changes over time, and whether oestrogen replacement therapy (ERT) influences this. DESIGN: A cohort study in healthy postmenopausal women without knee pain, initially selected on the basis of having either used ERT long term (more than five years) or never having used ERT. METHODS: 81 women (42 taking ERT and 39 non-users) had baseline knee radiographs and magnetic resonance imaging (MRI) on the dominant knee; 57 of these (70%) were followed with repeat MRI approximately 2.5 years later. Knee cartilage volume was measured at baseline and at follow up. Risk factors assessed at baseline, including ERT use, were tested for their association with change in knee cartilage volume over time. RESULTS: 29 subjects who were initially taking ERT and 28 non-users at baseline completed the study. Total tibial articular cartilage decreased, on average, by (mean (SD)) 2.4 (3.2)% per year (95% confidence interval for mean, 1.5% to 3.2%). Average annual reduction in medial and lateral tibial cartilage was 2.4 (3.6)% (1.4% to 3.3%) and 2.3 (4.2)% (1.2% to 3.4%), respectively. No association between ERT and the rate of reduction in cartilage volume was shown. CONCLUSIONS: Mean tibial cartilage volume loss in healthy postmenopausal women is between 1.5% and 3.2% a year. Whether this rate of change is similar throughout adult life or in men will require further investigation.

Cartilage, Articular↗

PubMed2004

How does tibial cartilage volume relate to symptoms in subjects with knee osteoarthritis?

BACKGROUND: No consistent relationship between the severity of symptoms of knee osteoarthritis (OA) and radiographic change has been demonstrated. OBJECTIVES: To determine the relationship between symptoms of knee OA and tibial cartilage volume, whether pain predicts loss of cartilage in knee OA, and whether change in cartilage volume over time relates to change in symptoms over the same period. METHOD: 132 subjects with symptomatic, early (mild to moderate) knee OA were studied. At baseline and 2 years later, participants had MRI scans of their knee and completed questionnaires quantifying symptoms of knee OA (knee-specific WOMAC: pain, stiffness, function) and general physical and mental health (SF-36). Tibial cartilage volume was determined from the MRI images. RESULTS: Complete data were available for 117 (89%) subjects. A weak association was found between tibial cartilage volume and symptoms at baseline. The severity of the symptoms of knee OA at baseline did not predict subsequent tibial cartilage loss. However, weak associations were seen between worsening of symptoms of OA and increased cartilage loss: pain (r(s) = 0.28, p = 0.002), stiffness (r(s) = 0.17, p = 0.07), and deterioration in function (r(s) = 0.21, p = 0.02). CONCLUSION: Tibial cartilage volume is weakly associated with symptoms in knee OA. There is a weak association between loss of tibial cartilage and worsening of symptoms. This suggests that although cartilage is not a major determinant of symptoms in knee OA, it does relate to symptoms.

Adult↗

PubMed2004

Sagittal gait patterns in spastic diplegia.

Classifications of gait patterns in spastic diplegia have been either qualitative, based on clinical recognition, or quantitative, based on cluster analysis of kinematic data. Qualitative classifications have been much more widely used but concerns have been raised about the validity of classifications, which are not based on quantitative data. We have carried out a cross-sectional study of 187 children with spastic diplegia who attended our gait laboratory and devised a simple classification of sagittal gait patterns based on a combination of pattern recognition and kinematic data. We then studied the evolution of gait patterns in a longitudinal study of 34 children who were followed for more than one year and demonstrated the reliability of our classification.

Adolescent↗

PubMed2003

Comparison of tibial cartilage volume and radiologic grade of the tibiofemoral joint.

OBJECTIVE: To compare tibial cartilage volume as measured by magnetic resonance imaging (MRI) with radiologic assessment of the tibiofemoral joint. METHODS: The MRI-determined tibial cartilage volume was compared with the radiologic grade of individual features of osteoarthritis (osteophytes and joint space narrowing [JSN]) in 252 subjects (mean +/- SD age 60.2 +/- 10 years, 62% female) who were participating in studies of knee cartilage. RESULTS: JSN seen on both medial and lateral radiographs of the tibiofemoral joint was inversely associated with the respective tibial cartilage volume. This inverse relationship was strengthened with adjustment for age, sex, body mass index (BMI), and bone size. After adjustment for these confounders, for every increase in JSN grade (0-3), the medial tibial cartilage volume was reduced by 257 mm(3) (95% confidence interval [95% CI] 193-321) and the lateral tibial cartilage volume by 396 mm(3) (95% CI 283-509). The relationship between mean cartilage volume and radiologic grade of JSN was linear. Based on results in the subgroup of subjects with normal radiographic findings, we have proposed a model to estimate average "normal" cartilage volume in men and women for a given age, BMI, and bone size. CONCLUSION: The results of this study demonstrate a strong negative, linear association between medial and lateral tibial cartilage volume and increasing grade of JSN. Using data from radiographically normal subjects, we have proposed a simple model for estimating "normal" cartilage volume. However, larger studies will be needed to confirm these findings and to determine whether they are valid in younger subjects.

Aged↗

PubMed2003

Uptime as a measure of recovery in children postappendectomy.

PURPOSE: The aim of this study was to objectively measure recovery time after open and laparoscopic appendectomy using an activity monitor (PAL 1). METHODS: The PAL 1 records the amount of time that the subject is upright (uptime). Children wore the PAL 1 for 10 days continuously, beginning within the first 48 hours postoperatively. RESULTS: Uptime data were collected for 5 or more days for 42 children (open, n = 16; laparoscopic, n = 26). All children had low levels of uptime in the initial postoperative period. There was weak evidence of a quicker recovery rate for children in the laparoscopic group (P =.09). The difference in mean uptime between groups was of statistical significance by day 7 postoperatively with children in the laparoscopic group having a higher mean uptime than those in the open group (difference of 0.7 hours; 95% confidence intervals 0.0 to 1.4 hours in a 24-hour period). CONCLUSIONS: The results of this study show that recovery postappendectomy can be quantified by the measurement of uptime and that children undergoing a laparoscopic procedure may recover marginally more quickly than those undergoing an open procedure.

Adolescent↗

PubMed2003

Uptime normative values in children aged 8 to 15 years.

The 'Uptimer' is a custom-made lightweight battery-operated remote activity monitor that records the amount of time an individual spends in the upright position, which is also known as 'uptime'. The aims of this study were to determine levels of uptime over 24 hours and the relation between uptime and a child's age, sex, height, weight, and body mass index (BMI). Uptime was recorded in 529 normally developing children (318 females, 211 males), aged between 8 and 15 years. All children wore an Uptimer continuously for a 24-hour period that included a typical school day. Mean uptime for children in this study was 5.4 hours (SD 1.3; range 1.5 to 10.3 hours), over a 24-hour period. Uptime followed approximately a normal distribution in this population and did not have a linear relation to age, height, weight, nor BMI. Results of this study may be used as a normative database for the evaluation of uptime in children with physical disabilities.

Adolescent↗