Related Experiment Video
Updated: Jul 24, 2025
Lower Limb Biomechanical Analysis of Healthy Participants
Published on: April 15, 2020
Quadriceps handheld dynamometry during the post-ICU trajectory: using strictly the same body position is mandatory
Anne-Françoise Rousseau1, Nadia Dardenne2, Isabelle Kellens3
1Intensive Care Department and Burn Center, University Hospital, University of Liège, Sart-Tilman B35, Hippocrate Avenue 1, 4000, Liège, Belgium. afrousseau@chuliege.be.
Background:
The level of quadriceps strength (QS) generated in the supine or seated position is not similar. For QS follow-up from intensive care unit (ICU) stay to recovery, getting comparable measures is essential. This study aimed to develop and validate new equations for estimating QS in a given position based on the measurement taken in another one.
Methods And Results:
Isometric QS was measured using a handheld dynamometer and a standardized protocol in a supine and in a seated position. In a first cohort of 77 healthy adults, two QS conversion equations were developed using a multivariate model integrating independent parameters such as age, sex, body mass index (BMI) and baseline QS. These equations were tested in two cohorts for external validation, using the interclass correlation coefficient (ICC) and Bland-Altman graphical method. Only one was validated in the second cohort (62 different healthy adults): the ICC was 0.87 (95% CI 0.59-0.94) and the bias was - 0.49 N/Kg (limits of agreement: - 1.76-0.78 N/kg). However, this equation did not perform well in the third cohort (50 ICU survivors): the ICC was 0.60 (95% CI 0.24-0.78), and the bias was - 0.53 N/Kg (limits of agreement: - 1.01-2.07 N/kg).
Conclusions:
As no conversion equation has been validated in the present study, repeated QS measurements should be performed strictly in the same standardized and documented position.
