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PubMed · 7972366

Performance characteristics of the Kin-Com dynamometer.

T P Mayhew·J M Rothstein·S D Finucane·R L Lamb
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Abstract

BACKGROUND AND PURPOSE: The purpose of this study was to assess the performance characteristics of a Kin-Com dynamometer (model #500-11) under controlled conditions. METHODS: Comparisons were made between measurements of force, angle, and velocity obtained from the Kin-Com and measurements acquired from an external recording system of known weights, angles, and user-set velocities. The strength of the linear relationships between measurements obtained with the different recording systems was analyzed using a coefficient of determination (r2). An intraclass correlation coefficient (ICC[2,1]) was used to examine the reliability of the force, angle, and velocity measurements obtained with each recording system on 2 different days. RESULTS: In all conditions, the coefficient of determination for the force, angle, and velocity comparisons was above .99. The ICC for between-day comparisons for all force, angle, and velocity measurements was above .99. CONCLUSION AND DISCUSSION: Our results indicate that the static measurements of force and angle that are necessary for use in the gravity-correction procedure and isometric testing are accurate and replicable between days. The Kin-Com dynamometer's control system regulating lever arm velocity is also accurate and replicable under a no-load condition. It was ascertained during the velocity testing that the use of any acceleration and deceleration mode other than "high" resulted in a loss of excursion of the lever arm.

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AccelerationBiasBiomechanical PhenomenaCalibrationDecelerationDiagnosis, Computer-AssistedElectrodiagnosisEquipment DesignGravitationHumansLinear ModelsMaterials TestingMuscle ContractionPhysical Therapy ModalitiesReproducibility of ResultsSignal Processing, Computer-AssistedWeight-BearingComparative StudyJournal Article

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T P Mayhew, J M Rothstein, S D Finucane, R L Lamb. 1994. Performance characteristics of the Kin-Com dynamometer.. https://doi.org/10.1093/ptj%2F74.11.1047

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