Biomedical subjects

Anthony C Redmond

Publications and source records attributed to Anthony C Redmond.

8 recordsLinked to original sources

PubMed2007

The Foot Posture Index: Rasch analysis of a novel, foot-specific outcome measure.

OBJECTIVE: To investigate the internal construct validity of a clinician-assessed measure of foot position, the Foot Posture Index (FPI), versions FPI-8 and FPI-6. DESIGN: Rasch analysis of baseline FPI scores from studies conducted during the development of the instrument. SETTING: A community-based and a hospital-based study, conducted at 2 institutions. PARTICIPANTS: Measures were obtained from 143 participants (98 men, 45 women; age range, 8-65y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Rasch analysis was undertaken using RUMM2020 software in order to evaluate the following properties of the FPI: unidimensionality of each item included in the FPI, the differential item functioning (DIF) of each item, and item and person separation indices. RESULTS: In the developmental draft of the instrument, the 8-item FPI-8 showed some misfit to the Rasch model (chi(16)(2) test=27.63, P=.03), indicating lack of unidimensionality. Two items were identified as problematic in the Rasch modeling: Achilles' tendon insertion (Helbing's sign), which showed illogical response ordering and "congruence of the lateral border of the foot," which showed misfit, indicating that this item may be measuring a different construct (chi(2)(2) test=15.35, P<.01). All FPI-8 items showed an absence of DIF, and the person separation index (PSI) was good (PSI=.88). The revised FPI-6, which does not include the 2 problematic items, showed unidimensionality (chi(12)(2) test=11.49, P=.49), indicating a good overall fit to the model, and improvement over the preliminary version. With the removal of the 2 problematic items, there were no disordered thresholds; all items remained DIF free and all individual items displayed a good fit to the model. The person-separation index for the FPI was similar for both the 8-item (FPI-8=.880) and 6-item (FPI-6=.884) versions. CONCLUSIONS: The original FPI-8 showed significant mismatching to the model. The 2 items in the FPI-8 that were identified as problematic in clinical validation studies were also found to be contributing to the lack of fit to the Rasch model. The finalized 6-item instrument showed good metric properties, including good individual item fit and good overall fit to the model, along with a lack of differential item functioning. This analysis provides further evidence for the validity of the FPI-6 as a clinical instrument for use in screening studies and shows that it has the potential to be analyzed using parametric strategies.

Adolescent↗

PubMed2006

Weight-bearing passive dorsiflexion of the hallux in standing is not related to hallux dorsiflexion during walking.

STUDY DESIGN: Case control study. OBJECTIVE: To explore the validity of the assumptions underpinning the Hubscher maneuver of hallux dorsiflexion in relaxed standing, by comparing the relationship between static and dynamic first metatarsophalangeal (MTP) joint motions in groups differentiated by normal and abnormal clinical test findings. BACKGROUND: Limitation of motion at the first MTP joint during gait may be due to either structural or functional factors. Functional hallux limitus (FHL) has been proposed as a term to describe the situation in which the first MTP joint shows no limitation when non-weight bearing, but shows limited dorsiflexion during gait. One clinical test of first MTP joint limitation during standing (the Hubscher maneuver or Jack's test) has become widely used in physical therapy, orthopedic, and podiatric assessments, supposedly to assess for the presence of hallux limitations during gait. The utility of the test is based on an assumption that restriction during the static maneuver is predictive of functional limitation at this joint during gait. Despite a lack of evidence for the validity of such an assumption, the outcome of the static test is often used to infer risk of overuse injury or as an outcome for functional therapy. This paper examines the validity of the assumptions supporting this widely used static test. METHODS AND MEASURES: First-MTP-joint motion was assessed using an electromagnetic motion tracking system in cases (n = 15) demonstrating clinically limited passive hallux dorsiflexion in relaxed standing, and in 15 controls matched for age and gender and demonstrating a clinically normal Hubscher maneuver. Maximum hallux dorsiflexion was measured with the subject non-weight bearing (seated), during relaxed standing, and during normal walking. RESULTS: Hallux dorsiflexion was similar in cases and controls when motions were measured non-weight bearing (cases mean +/- SD, 55.0 degrees +/- 11.0 degrees; controls mean + SD, 55.0 degrees +/- 10.7 degrees), confirming the absence of structural joint change. In relaxed standing, maximum dorsiflexion was 50% less in cases (mean +/- SD, 19.0 degrees +/- 8.9 degrees) than in the controls (mean +/- SD, 39.4 degrees +/- 6.1 degrees; P < .001), supporting the initial test outcome and confirming the visual test observation of static functional limitation in the case group. During gait, however, cases (mean +/- SD, 36.4 degrees +/- 9.1 degrees), and controls (mean +/- SD, 36.9 degrees +/- 7.9 degrees) demonstrated comparable maximum dorsiflexion (P = .902). There was no significant relationship between static and dynamic first MTP joint motions (r = 0.186, P = .325). CONCLUSION: The clinical test of limited passive hallux dorsiflexion in stance is a valid test only of hallux dorsiflexion available during relaxed standing. There is no association between maximum dorsiflexion observed during a static weight-bearing examination and that occurring at the same joint during walking.

Adult↗

PubMed2005

Development and validation of a novel rating system for scoring standing foot posture: the Foot Posture Index.

INTRODUCTION: The limitations of clinical methods for appraising foot posture are well documented. A new measure, the Foot Posture Index is proposed, and its development and validation described. METHODS: A four-phase development process was used: (i) to derive a series of candidate measures, (ii) to define an appropriate scoring system, (iii) to evaluate the validity of components and modify the instrument as appropriate, and (iv) to investigate the predictive validity of the finalised instrument relative to static and dynamic kinematic models. Methods included initial concurrent validation using Rose's Valgus Index, determination of inter-item reliability, factor analysis, and benchmarking against three dimensional kinematic models derived from electromagnetic motion tracking of the lower limb. RESULTS: Thirty-six candidate components were reduced to six in the final instrument. The draft version of the instrument predicted 59% of the variance in concurrent Valgus Index scores and demonstrated good inter item reliability (Cronbach's alpha = 0.83). The relevant variables from the motion tracking lower limb model predicted 58-80% of the variance in the six components retained in the final instrument. The finalised instrument predicted 64% of the variance in static standing posture, and 41% of the variance in midstance posture during normal walking. CONCLUSION: The Foot Posture Index has been subjected to thorough evaluation in the course of its development and a final version is proposed comprising six component measures that performed satisfactorily during the validation process. The Foot Posture Index assessment is quick and simple to perform and allows a multiple segment, multiple plane evaluation that offers some advantages over existing clinical measures of foot posture.

Adult↗

PubMed2005

The relationship between hallux dorsiflexion and ankle joint complex frontal plane kinematics: a preliminary study.

BACKGROUND: It has been suggested that the function of the first metatarsophalangeal joint may be related to the motion of the ankle joint complex. OBJECTIVE: This study explored the relationship between ankle joint complex and first metatarsophalangeal joint motion during gait in a group of 14 who demonstrated clinically limited passive hallux dorsiflexion in quiet standing (cases), and 15 matched controls. METHOD: An electromagnetic tracking system was used to measure the ankle joint complex frontal plane motion and first metatarsophalangeal joint sagittal plane motion during gait, in both cases and controls. The case group was then evaluated further to investigate the effect of an orthosis on first metatarsophalangeal joint motion. FINDINGS: The correlation between maximum ankle joint complex eversion and maximum first metatarsophalangeal joint dorsiflexion during gait was r=0.471. Within the case group, maximum rearfoot eversion was reduced following the application of the orthoses, but there was no change in sagittal first metatarsophalangeal joint rotations. INTERPRETATION: The relationship between maximum ankle joint complex eversion and first metatarsophalangeal joint dorsiflexion kinematics found in this study was moderate, and decreasing maximum ankle joint complex eversion with an orthosis did not result in any increase in first metatarsophalangeal joint dorsiflexion during gait in patients with functional first metatarsophalangeal joint limitation. These results do not support the assumption that ankle joint complex eversion influences first metatarsophalangeal joint motion substantially.

Adult↗

PubMed2002

Integrating research into the clinic. What evidence based practice means to the practising podiatrist.

This paper is the first in a series of three aimed at introducing clinicians to current concepts in research, and outlining how they may be able to apply these concepts to their own clinical practice. It has become evident in recent years that while many practitioners may not want to become actively involved in the research process, simply keeping abreast of the burgeoning publication base will create new demands on their time, and will often require the acquisition of new skills. This series introduces the philosophies of integrating what sometimes may appear to be abstract research into the realities of the clinical environment. It will provide practitioners with an accessible summary of the tools required in order to understand the research process. For some, it is hoped this series may provide some impetus for the contemplative practitioner to become a more active participant in the research process. This first paper addresses how the evidence based practice (EBP) revolution can be used to empower the individual practitioner and how good quality evidence can improve the overall clinical decision making process. It also suggests key strategies by which the clinician may try to enhance their clinical decision making process and make research evidence more applicable to their day to day clinical practice.

Clinical Competence↗

PubMed2002

'Horses for Courses': the differences between quantitative and qualitative approaches to research.

Some clinicians may feel dissociated from, and intimidated by the ever-increasing emphasis on research. However, with an understanding of some of the basic principles and key terms, research can feel less daunting. It is the aim of this article, the second in a series of three focusing on understanding research, to introduce clinicians to the different approaches to research, to improve understanding of what the approaches mean, and to highlight when a particular approach may be appropriate. Furthermore, the article will provide an explanation of some of the common terms used within clinical research. This should aid the clinician in applying good, simple, scientific principles to evaluating clinical research evidence.

Evaluation Studies as Topic↗

PubMed2002

Understanding statistics. Putting p-values into perspective.

Understanding statistics can be one of the more difficult and daunting tasks facing the clinician attempting to understand and use the research literature. While the fundamental aim of including statistics in literature is to justify the conclusions and to enhance the information presented, all too often, statistics serve only to intimidate and alienate clinicians. There are two sources for this barrier to understanding: poor comprehension of statistics by clinicians, and inappropriate presentation of statistics by researchers. In the third of our papers on evidence-based practice and the clinician, some basic principles of statistics are introduced. Aspects such as the concepts of clinical and statistical significance are discussed, and an outline of the appropriate use of specific statistics is provided. The hope is that this will enable the clinician to better judge the applicability of statistical techniques as applied in the published literature. Some of the newer, more 'clinician friendly' statistical approaches are also presented. Finally some of the cheats and shortcuts commonly encountered in the presentation of research are discussed, and the methods for dealing with them are outlined.

Humans↗

PubMedDate not supplied

Effectiveness of low-Dye taping for the short-term management of plantar fasciitis.

Low-Dye taping is often used as a short-term treatment for plantar fasciitis. We evaluated the short-term effectiveness of low-Dye taping in relieving pain associated with plantar fasciitis. In this comparative study conducted at a university-based clinic, 65 participants with plantar fasciitis who received low-Dye taping for 3 to 5 days were compared with 40 participants who did not receive taping. Pain before and after treatment was measured using a visual analog pain scale. Analysis of the data was by the intention-to-treat principle, and a linear regression approach to analysis of covariance was used to compare effects. The visual analog pain scale score improved by a mean of 20 mm (from 44 to 24 mm) in the taping group and worsened by a mean of 6 mm (from 51 to 57 mm) in the control group. The analysis of covariance-adjusted difference in therapeutic effect favored the taping group by 31.7 mm (95% confidence interval, 23.6-39.9 mm) and was statistically significant (t = 7.71). In the short term, low-Dye taping significantly reduces the pain associated with plantar fasciitis. These findings are the first quantitative results to demonstrate the significant therapeutic effect of this treatment modality in relieving the symptoms associated with plantar fasciitis.

Bandages↗