To the top

Page Manager: Webmaster
Last update: 9/11/2012 3:13 PM

Tell a friend about this page
Print version

Validation of inertial me… - University of Gothenburg, Sweden Till startsida
To content Read more about how we use cookies on

Validation of inertial measurement units with optical tracking system in patients operated with Total hip arthroplasty

Journal article
Authors Roland Zügner
Roy Tranberg
J. Timperley
D. Hodgins
Maziar Mohaddes
Johan Kärrholm
Published in Bmc Musculoskeletal Disorders
Volume 20
ISSN 1471-2474
Publication year 2019
Published at Institute of Clinical Sciences, Department of Orthopaedics
Language en
Keywords Inertial measurement units, IMU's, Optical tracking system, Total hip arthroplasty, Gait, Gait analysis, gait analysis, knee osteoarthritis, lower-extremity, replacement, reliability, kinematics, parameters, patterns, kinetics, Orthopedics, Rheumatology
Subject categories Orthopedics


BackgroundPatient reported outcome measurement (PROMs) will not capture in detail the functional joint motion before and after total hip arthroplasty (THA). Therefore, methods more specifically aimed to analyse joint movements may be of interest. An analysis method that addresses these issues should be readily accessible and easy to use especially if applied to large groups of patients, who you want to study both before and after a surgical intervention such as THA. Our aim was to evaluate the accuracy of inertial measurement units (IMU) by comparison with an optical tracking system (OTS) to record pelvic tilt, hip and knee flexion in patients who had undergone THA.Methods49 subjects, 25 males 24 females, mean age of 73years (range 51-80) with THA participated. All patients were measured with a portable IMU system, with sensors attached lateral to the pelvis, the thigh and the lower leg. For validation, a 12-camera motion capture system was used to determine the positions of 15 skin markers (Oqus 4, Qualisys AB, Sweden). Comparison of sagittal pelvic rotations, and hip and knee flexion-extension motions measured with the two systems was performed. The mean values of the IMU's on the left and right sides were compared with OTS data.ResultsThe comparison between the two gait analysis methods showed no significant difference for mean pelvic tilt range (4.9-5.4 degrees) or mean knee flexion range (54.4-55.1 degrees) on either side (p>0.7). The IMU system did however record slightly less hip flexion on both sides (36.7-37.7 degrees for the OTS compared to 34.0-34.4 degrees for the IMU, p<0.001).ConclusionsWe found that inertial measurement units can produce valid kinematic data of pelvis- and knee flexion-extension range. Slightly less hip flexion was however recorded with the inertial measurement units which may be due to the difference in the modelling of the pelvis, soft tissue artefacts, and malalignment between the two methods or misplacement of the inertial measurement units.Trial registrationThe study has ethical approval from the ethical committee Regionala etikprovningsnamnden i Goteborg (Dnr: 611-15, 2015-08-27) and all study participants have submitted written approval for participation in the study.

Page Manager: Webmaster|Last update: 9/11/2012

The University of Gothenburg uses cookies to provide you with the best possible user experience. By continuing on this website, you approve of our use of cookies.  What are cookies?