Development of Tests for Arm Coordination Impairment in Paralympic Classification

BackgroundIn Paralympic sport, classification of impairment with the ability to detect misrepresentation of abilities is mandatory. In wheelchair rugby, there is currently no objective method to classify arm coordination impairment. In previous research, sufficient correlation between the spiral test (ST) and activity in wheelchair rugby was found in athletes with coordination impairment. However, the ST depends on maximum voluntary effort.PurposeTo assess if the ST is an objective test for arm coordination impairment, in which maximum voluntary effort can be distinguished from intentional misrepresentation. The aims of this study were to (1) assess the test-retest reliability of the ST and (2) assess if Fitts's law is applicable to the ST.MethodsNineteen volunteers without impairments performed two sessions with three STs per arm. The STs were projected and measured on a tablet and had three different indices of difficulty based on differences in spiral width. The time to complete the spiral was measured and a penalty time was added for each time the borderline of the spiral was touched (3 s) or crossed (5 s).ResultsTest-retest reliability was assessed using a Bland-Altman analysis and showed limits of agreement that were wider than the margins of 2SD from the group mean. Repeated measurement correlation coefficients between the index of difficulty according to Fitts's law and the movement time were > 0.95 (p-value < 0.001) for both test and retest. A post-hoc optimisation of penalty times revealed an optimum penalty time of 2.0 s for the dominant arm and 2.5 for the non-dominant arm for any contact with the margins of the spiral.ConclusionsThe ST has sufficient test-retest reliability and Fitts's law is applicable. Therefore, it is a promising option for classification of arm coordination impairment with the option to distinguish intentional misrepresentation from maximum voluntary effort

Understanding the impact of trunk and arm impairment on wheelchair rugby performance during competition

Purpose: To determine the effect of trunk and arm impairment on physical and technical performance during wheelchair rugby (WR) competition. Methods: Thirty-one highly trained WR players grouped according to their trunk (no trunk [NT]; some trunk [T] function) and arm impairment (poor [PAF]; moderate [MAF]; good [GAF] arm function) participated in 5 WR matches. Player’s physical (wheelchair mobility) and technical (ball handling) activities were analysed using an indoor tracking system and video analysis respectively. Results: Trunk impairment explained some of the variance in physical (10.6–23.5%) and technical (16.2–33.0%) performance. T covered more distance, had more possession, scored more goals, received and made more passes, yet spent less time at low speeds and performed fewer inbounds than NT (≤ 0.05). Arm impairment explained some of the variance in all physical (16.7–47.0%) and the majority of technical (13.1–53.3%) performance measures. MAF and GAF covered more distance, reached higher peak speeds, spent more time in higher speed zones, scored more goals, had more possession, received and made more passes, with a higher percentage of one-handed and long passes than PAF. GAF also received more passes and made a higher percentage of one-handed passes and defensive blocks than MAF (P ≤ 0.05). Conclusions: Arm impairment impacts a greater number of physical and technical measures of performance specific to WR than trunk impairment during competition. Having active finger function (GAF) yielded no further improvements in physical performance but positively influenced a small number of technical skill

Velocity-space sensitivity of the time-of-flight neutron spectrometer at JET

The velocity-space sensitivities of fast-ion diagnostics are often described by so-called weight functions. Recently, we formulated weight functions showing the velocity-space sensitivity of the often dominant beam-target part of neutron energy spectra. These weight functions for neutron emission spectrometry (NES) are independent of the particular NES diagnostic. Here we apply these NES weight functions to the time-of-flight spectrometer TOFOR at JET. By taking the instrumental response function of TOFOR into account, we calculate time-of-flight NES weight functions that enable us to directly determine the velocity-space sensitivity of a given part of a measured time-of-flight spectrum from TOFOR

Relationship of edge localized mode burst times with divertor flux loop signal phase in JET

A phase relationship is identified between sequential edge localized modes (ELMs) occurrence times in a set of H-mode tokamak plasmas to the voltage measured in full flux azimuthal loops in the divertor region. We focus on plasmas in the Joint European Torus where a steady H-mode is sustained over several seconds, during which ELMs are observed in the Be II emission at the divertor. The ELMs analysed arise from intrinsic ELMing, in that there is no deliberate intent to control the ELMing process by external means. We use ELM timings derived from the Be II signal to perform direct time domain analysis of the full flux loop VLD2 and VLD3 signals, which provide a high cadence global measurement proportional to the voltage induced by changes in poloidal magnetic flux. Specifically, we examine how the time interval between pairs of successive ELMs is linked to the time-evolving phase of the full flux loop signals. Each ELM produces a clear early pulse in the full flux loop signals, whose peak time is used to condition our analysis. The arrival time of the following ELM, relative to this pulse, is found to fall into one of two categories: (i) prompt ELMs, which are directly paced by the initial response seen in the flux loop signals; and (ii) all other ELMs, which occur after the initial response of the full flux loop signals has decayed in amplitude. The times at which ELMs in category (ii) occur, relative to the first ELM of the pair, are clustered at times when the instantaneous phase of the full flux loop signal is close to its value at the time of the first ELM

Improvement of the classification system for wheelchair rugby: athlete priorities

A representative sample (N=302) of the wheelchair rugby population responded to a survey about the classification system based on prioritized items by International Wheelchair Rugby Federation members. Respondents stated, "The classification system is accurate but needs adjustments" (56%), "Any athlete with tetraequivalent impairment should be allowed to compete" (72%), "Athletes with cerebral palsy and other coordination impairments should be classified with a system different than the current one" (75%), and "The maximal value for trunk should be increased from 1.0 to 1.5" (67%). A minority stated, "Wheelchair rugby should only be open to spinal cord injury and other neurological conditions" (36%) and "There should be a 4.0 class" (33%). Results strongly indicated that athletes and stakeholders want adjustments to the classification system in two areas: a focus on evaluation of athletes with impairments other than loss of muscle power caused by spinal cord injury and changes in classification of trunk impairment.status: publishe

The impact of trunk impairment on performance of wheelchair activities with a focus on wheelchair court sports: a systematic review

Trunk impairment seems to impact significantly on performance in wheelchair court sports, but evidence to support this impression has never been systematically assessed. The objective of this study is to systematically review, describe and synthesise the literature investigating the impact of trunk impairment on wheelchair activities in court sports.status: publishe

Construct Validity of the Trunk Impairment Classification System in Relation to Objective Measures of Trunk Impairment

To determine the validity of the Trunk Impairment Classification system (TIC) with 4 possible scores (0, most impaired; 0.5; 1.0; 1.5, least impaired) in relation to objective, instrumented measures of impairment.status: publishe

Objective Measurement of Ball-Handling Proficiency in Wheelchair Sports : A Systematic Review.

Background: In Paralympic sports, classification of athletes based on the impact of impairments on the ability to perform is needed, to prevent a one-sided and predictable outcome of the competition in which the least impaired athlete has the best chance to win. Classification is developing from expert opinion based to evidence based. In wheelchair court sports, there is evidence to support the impact of impairment on wheeled mobility, but not on ball handling. To assess the impact of impairment on the ability to perform ball-handling activities, standardised tests for ball handling are needed. Purpose: To assess if reliable and valid standardised tests for the measurement of ball-handling proficiency in a wheelchair or able-bodied court sports exist; to assist in the development of Evidence-Based Classification (EBC) in wheelchair court sports according to the guidelines of the International Paralympic Committee (IPC). Methods: The review was conducted according to the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) statement. Search terms used were "wheelchair," "ball," "ball sports," "test," and "performance." Databases searched were Medline, Embase, PubMed, and Sport Discus. Study quality was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology checklist. Results: Twenty-two articles were included. Foundational Movement Skills in ball-handling proficiency were assessed. Tests for throwing maximal distance showed sufficient reliability and validity. Precision in throwing showed low-to-moderate reliability and conflicting results in validity. Throwing techniques differed between studies. Dribbling the ball showed high reliability, but conflicting results in validity. Conclusions: Tests for throwing maximal distance, throwing precision, and dribbling the ball can be used in standardised tests for activity limitation in wheelchair court sports. However, tests need to be adapted and standardised and then reassessed for reliability and validity in athletes with and without arm impairment