Carol Ann Flavell

Inter-rater reliability of classification systems in chronic low back pain populations

Abstract Background: Low back pain (LBP) classification systems are used by physical therapists to classify patients. Classification systems require observation, and are at risk of rater bias and erroneous classification decisions, if the reliability among raters is poor. Rater reliability of individual systems in subgroups of LBP is important, to justify their continued utility. Objectives: The purpose of this research was to investigate the reliability of LBP classification systems when applied exclusively to chronic low back pain (CLBP) populations. Methods: A systematic electronic database search of Medline, CINAHL, PEDro, The Cochrane Library, Informit, and Scopus was conducted. Studies that reported reliability and detailed reliability statistics of one or more LBP classification systems, exclusively in CLBP populations were included. Two independent reviewers used the Quality Appraisal of Reliability Studies (QAREL) tool to evaluate quality and risk of bias for each study. Four eligible studies were identified. Results: The Motor Control Impairment Classification System (OCS) and the Movement System Impairment Classification (MSI) were the only systems assessed for inter-rater reliability in CLBP populations. Inter-rater reliability for the MSI was substantial and inter-rater reliability for the OCS ranged from fair to almost perfect. However, risk of bias was high in the studies. Reported inter-rater reliability appeared to have an inverse relationship to study quality and risk of bias. Conclusions: The findings of this review identified insufficient evidence to determine conclusions on inter-rater reliability when LBP classification systems are applied for CLBP. Therefore, recommendations to substantiate their use to classify patients reliably among therapists should be considered with caution.

Methodological consistency and measurement reliability of transversus abdominis real time ultrasound imaging in chronic low back pain populations: a systematic review

Background: Real time ultrasound imaging (RTUI) is used to measure transversus abdominis (TrA) thickness in low back pain (LBP) populations. However, individuals with chronic low back pain (CLBP) pose specific imaging challenges, such as older age and higher body mass index, compared to asymptomatic populations or acute and sub-acute LBP groups. These challenges potentially increase measurement error and may require different imaging methods. Objectives: This review describes the methodologies and reported reliability for RTUI measurement of TrA specific to CLBP populations. Methods: A systematic database search of Medline, CINAHL, PEDro, the full Cochrane library, Scopus, and Informit identified 20 studies that used RTUI to measure TrA of CLBP participants. Two independent raters appraised the quality of the studies using the QualSyst and the QAREL critical appraisal tools. Results: Methodological quality varied from low to high. Methods for patient and transducer positioning and muscle measurement were inconsistent between studies. Eight articles cited reliability results from past studies of non-CLBP populations. Only two studies reported reliability in CLBP populations specifically and found higher Intraclass Correlation Coefficients for thickness measures at rest (0.63–0.97), compared to thickness change over time or contraction ratios (0.28–0.80). Conclusions: Inconsistency of methodology, variable methodological quality, and limited and variable reliability reporting was highlighted in this review. This LBP subgroup poses challenges for RTUI, therefore future research should include standarized methods for image acquisition. This will improve the quality of study methods, reliability of TrA measurement, and improve the applicability and comparibility of research evidence available to clinicians.

Reply to the letter to the editor regarding ‘Classification characteristics of a chronic low back pain population using a combined McKenzie and patho-anatomical assessment’

[Extract] We would like to address the questions raised in the letter as they are presented. We acknowledge and respect the outstanding work of Robin McKenzie and the work which continues to be conducted by the McKenzie Institute and its members. Combining a McKenzie assessment with patho-anatomical classifications was never meant as a substitute for the McKenzie classifications and subgroupings which is an established classification process. However, we wish to clarify some details.

Injuries to the triceps surae muscle of elite rugby union front rowers: a 3 dimensional kinematic analysis of the front row during live scrimmaging

Introduction: The increasing incidence of injury to the triceps surae muscle in high performance front row rugby union (rugby) players has stimulated a need to investigate the events surrounding this injury. Previous research has linked triceps surae muscle injuries with both scrummaging and activities which mimic those of scrummaging, but possible mechanisms of injury remain uninvestigated. In addition, limited published data exists that has reported the biomechanics of scrum technique in high performance players. Of these studies the majority have been undertaken using scrummaging machines, with research on the biomechanics of live scrummaging even less well documented. Accordingly, the purpose of this study was to investigate the lower limb kinematics during a series of scrummaging drills. It was hypothesized that analysing the biomechanics of this aspect of game play would provide greater understanding of the possible causes and mechanisms for triceps surae injury. Methodology: Eleven high performance front row rugby players were landmarked for 16 anatomical points and then videoed during a series of 2-on-1 (attacking) and 1 -on-2 (defensive) live scrummaging drills using four digital camcorders (Panasonic NV-GS180GN) operating at 50 Hz. On completion of data collection, the 16 land marked anatomical points were digitised for each frame using APAS motion analysis software and a three-dimensional model of the trunk and lower limb developed. A series of one way ANOVA were used to determine if the spatio temporal descriptors of the lower limb kinematics differed between defensive and attacking scrummaging technique. All statistical analyses were performed using SPSS for Windows (version 17). A significance level of P < 0.05 was used for all analysis. Results/conclusions: Results (presented as mean ± SD) showed numerous significant differences in a range of spatio temporal variables between defensive and attacking scrum types. Analysis indicated a clear trend towards more extended positions in the defensive scrum drills. For example, relative ankle angular displacement from foot strike to toe-off varied significantly (P < 0.05) between the attacking (−13° [±7]) and defensive scrum drills (3° [±8]), as did relative ankle angular displacement at peak extension velocity between the attacking (108 deg [±12]) and defensive scrum drills (97° [±9]) during single leg stance. It was concluded that these more extended joint positions contribute to increased triceps surae load during attacking scrummaging activity. This study also showed that the scrummaging techniques of the subjects had the potential to predispose them to triceps surae injury.