Biomechanical Gait Variable Estimation Using Wearable Sensors after Unilateral Total Knee Arthroplasty

Abstract

Total knee arthroplasty is a common surgical treatment for end-stage osteoarthritis of the knee. The majority of existing studies that have explored the relationship between recovery and gait biomechanics have been conducted in laboratory settings. However, seamless gait parameter monitoring in real-world conditions may provide a better understanding of recovery post-surgery. The purpose of this study was to estimate kinematic and kinetic gait variables using two ankle-worn wearable sensors in individuals after unilateral total knee arthroplasty. Eighteen subjects at least six months post-unilateral total knee arthroplasty participated in this study. Four biomechanical gait variables were measured using an instrumented split-belt treadmill and motion capture systems. Concurrently, eleven inertial gait variables were extracted from two ankle-worn accelerometers. Subsets of the inertial gait variables for each biomechanical gait variable estimation were statistically selected. Then, hierarchical regressions were created to determine the directional contributions of the inertial gait variables for biomechanical gait variable estimations. Selected inertial gait variables significantly predicted trial-averaged biomechanical gait variables. Moreover, strong directionally-aligned relationships were observed. Wearable-based gait monitoring of multiple and sequential kinetic gait variables in daily life could provide a more accurate understanding of the relationships between movement patterns and recovery from total knee arthroplasty.

Current clinical utilisation of wearable motion sensors for the assessment of outcome following knee arthroplasty: a scoping review

“…A triaxial accelerometer was the most commonly used sensor incorporated in the functional assessment subgroup, with 15 of 16 studies (94%)8 19–32 using the sensor alone or in combination with other instrumentation. Seven of the functional studies exclusively used triaxial accelerometers as the means for data collection during functional analysis 8 20–22 24 28 31. Three studies used IMUs with an integrated triaxial accelerometer and triaxial gyroscope,19 27 29 while three others recorded gait with a 9 df IMU integrating triaxial accelerometer, gyroscope and magnetometer 25 26 30.…”

“…Most studies (13 studies, 81%)8 19–22 24–30 33 included pre-operative data collection with repeated tests at one or more time points up to 1-year post-operatively, most frequently up to 6 weeks after surgery. Three studies collected data at an unspecified point any time greater than 6 months post-operatively 23 31 32…”

“…The evaluation of gait symmetry and variability was the most common sensor-based outcome metric (eight studies, 50%),8 21 24 26 28 29 31 32 while dynamic range of motion was also commonly reported (six studies, 38%) 19 25–27 29 30. A wide variety of spatiotemporal gait parameters were also reported, including varied combinations of walking speed,8 23 24 26 29 32 cadence,8 26 32 stride length,8 23 24 26 29 32 stride time,8 19 29 stance time,24 29 vertical displacement,8 32 swing power24 and foot fall 24.…”

“…Three studies reported functional performance primarily based on a stand-alone function score 22 32 33. Other studies reported on gait function through a variety of other parameters including acceleration magnitudes,21 26 31 activity transitions,20 multiple aspects of dynamic range of motion19 26 27 29 and varied measures of gait symmetry, inefficiency and variability 8 21 24 26 28 29 31 32…”

Self-Reported and Performance-Based Outcome Measures Estimation Using Wearables After Unilateral Total Knee Arthroplasty

“…For example, Rodríguez-Martín et al ( 2017 ) used a triaxial accelerometer and machine learning to better detect freezing of gait in patients with Parkinson's disease as opposed to self-reported questionnaires, and Na and Buchanan ( 2020 ) validated the use of wearable technology against self-reported measures for stability in individuals with knee OA. Our previous work estimated kinematic and kinetic gait parameters from inertial gait variables using wearable devices (Youn et al, 2018 ), but the efficacy of inertial gait variables in determining self-reported patient outcomes and functional performance based measures in individuals post-TKA has yet to be explored. While it is often suggested that movement patterns are associated with functional ability and quality of life, few studies have evaluated the relationship between objective measures of gait and clinical outcomes.…”