Evaluating the Feasibility of Electrical Impedance Tomography for Monitoring Knee Angle and Muscle Strength: Towards Application in Total Knee Replacement Rehabilitation

• Published in: IEEE International Symposium on Circuits and Systems proceedings pp. 1 - 5
• Main Authors: Liang, Lishan, Yao, Tianyang, Tehrany, Rokhsaneh, Player, Darren, Carlson, Tom, Demosthenous, Andreas, Wu, Yu
• Format: Conference Proceeding
• Language: English
• Published: IEEE 25.05.2025
• Subjects: Bioimpedance; Biomedical monitoring; Correlation; Data models; Electrical impedance tomography; knee Angle and muscle strength monitoring; Knee replacement; Long short term memory; Monitoring; Muscles; Pain; total knee replacement
• ISSN: 2158-1525
• DOI: 10.1109/ISCAS56072.2025.11043497

Rehabilitation following total knee replacement (TKR) principally aims to reduce pain and restore knee muscle strength and function, which necessitates objective monitoring. Given the growing interest in wearable technologies for rehabilitation, this paper investigates the feasibility of using electrical impedance tomography (EIT) to monitor and estimate muscle activity, specifically focusing on resultant knee angle (KA) and muscle strength (MS). A data collection system was designed to simultaneously capture EIT data, kinematic and physiological reference data, namely KA and MS, followed by two experiments. Data processing methods, such as region of interest (ROI) selection and modelling of the correlation between EIT and reference data, were used to assess feasibility. The results indicate that the long short-term memory (LSTM) model achieved an R² value of 0.97, suggesting a strong correlation between the EIT data and KA. While EIT demonstrated potential in detecting KA, it did not show effectiveness in capturing changes in muscle activity and MS during isometric contractions.