Data/Code: Objective monitoring of functional recovery after total knee and hip arthroplasty using sensor-derived gait measures

Abstract

Background:   Inertial sensors hold the promise to objectively measure functional recovery in the clinical setting after total knee (TKA) and hip arthroplasty (THA), but their value in addition to patient-reported outcome measures (PROMs) has yet to be demonstrated. This study investigated functional recovery after TKA and THA using inertial sensors, and compared results to recovery of pain and function according to PROMs.

Methods:        PROMs and gait were assessed before and at two and fifteen months after TKA (n=24) and THA (n=24). Gait was compared with healthy individuals (n=27) of similar age. Gait data were collected using inertial sensors on the feet, lower back, and trunk. Participants walked for two minutes back and forth over a 6m walkway with 180° turns. PROMs were obtained using the Knee Injury and Osteoarthritis Outcome Scores and Hip Disability and Osteoarthritis Outcome Score.

Results:           Gait parameters recovered to the level of healthy controls after both TKA and THA. Early improvements were found in trunk kinematics, while spatiotemporal parameters mainly improved between two and fifteen months after TKA and THA. Compared to recovery profiles of PROMs, gait parameters showed a different trajectory, with a marked discordance between the outcome of both methods at two months post-operatively.

Conclusion:     Inertial sensors are well-suited to monitor gait recovery in the clinical setting, providing complementary data on physical functioning compared to PROMs. Regarding group averages, all parameters improved markedly 15 months post-operatively. Future studies should explore the value of implementation of gait data to support shared and clinical decision making.