Kinematic analysis of isokinetic knee flexor and extensor tests

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Kinematic analysis of isokinetic knee flexor and extensor tests. / Alt, Tobias; Severin, Jannik; Nodler, Yannick; Horn, Dennis; El-Edrissi, Omar; Knicker, Axel; Strüder, Heiko Klaus.

In: Isokinetics and Exercise Science, Vol. 26, No. 1, 2018, p. 1-8.

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@article{bd8e21f9df4348b6a707bfded2cb0a63,
title = "Kinematic analysis of isokinetic knee flexor and extensor tests",
abstract = "BACKGROUND: Isokinetic dynamometry is widely considered the gold standard in mechanical muscle performance testing. Invariably, the moment-position raw data obtained from the dynamometer is directly analysed although kinematic inaccuracies may inherently exist.OBJECTIVE: To quantify the differences between two processing methods of isokinetic raw data: one based on the device's own software and one using a hybrid kinematic procedure.METHODS: Seventy-six healthy male participants performed unilateral concentric knee extensor (Qcon) (90° ROM) and eccentric knee flexor (Hecc) tests (110° ROM) at 150°/s. The knee angles were recorded by two high-speed cameras per body side.RESULTS: Compared to isokinetic data, kinematic analysis reduced the knee’s ROM by 17° for Qcon and by 21° for Hecc. Thus, the mean ‘isokinetic’ angular velocity declined to 121 and 122°/s, respectively. The angles of peak moment changed significantly (-5° for Qcon, +20° for Hecc). Contractional work decreased (-20{\%}) only for Qcon. The moments and angles derived from analysis of the DCR at the equilibrium point (DCRe) rose by 7{\%} and 20{\%} when the isokinetic raw data were linked with kinematic data. The comparison of both processing methods revealed very high (R²=91{\%}) and high (R²=69{\%}) relationships for DCRe moments and angles.CONCLUSIONS: Isokinetic raw data comprise kinematic inaccuracies caused by axis misalignment, evasive movements and anatomical features. Although a hybrid kinematic procedure is more time-consuming, it may enable a more valid clinical interpretation of the test findings",
author = "Tobias Alt and Jannik Severin and Yannick Nodler and Dennis Horn and Omar El-Edrissi and Axel Knicker and Str{\"u}der, {Heiko Klaus}",
year = "2018",
doi = "10.3233/IES-175172",
language = "English",
volume = "26",
pages = "1--8",
journal = "Isokinetics and Exercise Science",
issn = "0959-3020",
publisher = "IOS Press",
number = "1",

}

RIS

TY - JOUR

T1 - Kinematic analysis of isokinetic knee flexor and extensor tests

AU - Alt, Tobias

AU - Severin, Jannik

AU - Nodler, Yannick

AU - Horn, Dennis

AU - El-Edrissi, Omar

AU - Knicker, Axel

AU - Strüder, Heiko Klaus

PY - 2018

Y1 - 2018

N2 - BACKGROUND: Isokinetic dynamometry is widely considered the gold standard in mechanical muscle performance testing. Invariably, the moment-position raw data obtained from the dynamometer is directly analysed although kinematic inaccuracies may inherently exist.OBJECTIVE: To quantify the differences between two processing methods of isokinetic raw data: one based on the device's own software and one using a hybrid kinematic procedure.METHODS: Seventy-six healthy male participants performed unilateral concentric knee extensor (Qcon) (90° ROM) and eccentric knee flexor (Hecc) tests (110° ROM) at 150°/s. The knee angles were recorded by two high-speed cameras per body side.RESULTS: Compared to isokinetic data, kinematic analysis reduced the knee’s ROM by 17° for Qcon and by 21° for Hecc. Thus, the mean ‘isokinetic’ angular velocity declined to 121 and 122°/s, respectively. The angles of peak moment changed significantly (-5° for Qcon, +20° for Hecc). Contractional work decreased (-20%) only for Qcon. The moments and angles derived from analysis of the DCR at the equilibrium point (DCRe) rose by 7% and 20% when the isokinetic raw data were linked with kinematic data. The comparison of both processing methods revealed very high (R²=91%) and high (R²=69%) relationships for DCRe moments and angles.CONCLUSIONS: Isokinetic raw data comprise kinematic inaccuracies caused by axis misalignment, evasive movements and anatomical features. Although a hybrid kinematic procedure is more time-consuming, it may enable a more valid clinical interpretation of the test findings

AB - BACKGROUND: Isokinetic dynamometry is widely considered the gold standard in mechanical muscle performance testing. Invariably, the moment-position raw data obtained from the dynamometer is directly analysed although kinematic inaccuracies may inherently exist.OBJECTIVE: To quantify the differences between two processing methods of isokinetic raw data: one based on the device's own software and one using a hybrid kinematic procedure.METHODS: Seventy-six healthy male participants performed unilateral concentric knee extensor (Qcon) (90° ROM) and eccentric knee flexor (Hecc) tests (110° ROM) at 150°/s. The knee angles were recorded by two high-speed cameras per body side.RESULTS: Compared to isokinetic data, kinematic analysis reduced the knee’s ROM by 17° for Qcon and by 21° for Hecc. Thus, the mean ‘isokinetic’ angular velocity declined to 121 and 122°/s, respectively. The angles of peak moment changed significantly (-5° for Qcon, +20° for Hecc). Contractional work decreased (-20%) only for Qcon. The moments and angles derived from analysis of the DCR at the equilibrium point (DCRe) rose by 7% and 20% when the isokinetic raw data were linked with kinematic data. The comparison of both processing methods revealed very high (R²=91%) and high (R²=69%) relationships for DCRe moments and angles.CONCLUSIONS: Isokinetic raw data comprise kinematic inaccuracies caused by axis misalignment, evasive movements and anatomical features. Although a hybrid kinematic procedure is more time-consuming, it may enable a more valid clinical interpretation of the test findings

U2 - 10.3233/IES-175172

DO - 10.3233/IES-175172

M3 - Journal articles

VL - 26

SP - 1

EP - 8

JO - Isokinetics and Exercise Science

JF - Isokinetics and Exercise Science

SN - 0959-3020

IS - 1

ER -

ID: 3102227