Assessment of Gait Symmetry and Gait Normality Using Inertial Sensors: In-Lab and In-Situ Evaluation - Biomedical Engineering Systems and Technologies - page 215

Assessment of Gait Symmetry and Gait Normality
Using Inertial Sensors: In-Lab and In-Situ Evaluation

Anita Sant'Anna 1 , , Nicholas Wickstr om 1 ,
Helene Eklund 2 ,RolandZugner 3 , and Roy Tranberg 3

1 Intelligent Systems Lab, Halmstad University, Sweden
2 Center for Person-Centered Care, Sahlgrenska Academy, Sweden
3 Department of Orthopedics, Sahlgrenska Academy, Sweden
[e-mail]

Abstract. Quantitative gait analysis is a powerful tool for the assessment of a
number of physical and cognitive conditions. Unfortunately, the costs involved
in providing in-lab 3D kinematic analysis to all patients is prohibitive. Inertial
sensors such as accelerometers and gyroscopes may complement in-lab analysis
by providing cheaper gait analysis systems that can be deployed anywhere. The
present study investigates the use of inertial sensors to quantify gait symmetry and
gait normality. The system was evaluated in-lab, against 3D kinematic measure-
ments; and also in-situ, against clinical assessments of hip-replacement patients.
Results show that the system not only correlates well with kinematic measure-
ments but it also corroborates various quantitative and qualitative measures of
recovery and health status of hip-replacement patients.

Keywords: Gait analysis, Symmetry, Normality, Accelerometer, Gyroscope, In-
ertial sensors.

1 Introduction

Quantitative gait analysis (GA) can improve the assessment of a number of physical and
cognitive conditions. The importance of GA in the treatment of children with cerebral
palsy is well known and documented [1]. The use of GA to monitor and assess Parkin-
son's Disease [2], stroke [3], and orthopedic [4] patients have also been investigated.
Despite many positive results, GA is still not routinely used in the clinical setting.
Several factors contribute to the low adoption of GA as a routine clinical tool. Per-
haps the most significant factor is that the accepted gold standard for GA, in-lab 3D
motion capture (MOCAP), is simply not available to all patients. The costs involved in
equipping a gait lab and training personnel are prohibitive for many clinical institutions,
especially in underprivileged areas and developing countries.
The current alternative to MOCAP is observational gait analysis (OGA), which is
intrinsically subjective and sensitive to the observer's experience [5]. Recently, however,
large efforts have been employed in developing low-cost, inertial sensor systems that can
complement OGA with objective and reliable information. The success of such systems
will hopefully incur in a wide-spread adoption of quantitative GA as a clinical tool.

Corresponding author.