# Verification of Markerless Gait Analysis: Multi-Camera and Single-Camera Approaches in Comparison to Marker-Based Gait Analysis

## TL;DR

This study compares markerless gait analysis systems with a traditional marker-based system to evaluate their accuracy and reliability in measuring gait parameters.

## Contribution

The study validates the use of markerless gait analysis systems, highlighting their potential as alternatives to traditional marker-based systems.

## Key findings

- Both single-camera and multi-camera markerless systems showed good-to-excellent reliability in spatiotemporal parameters like step length and gait speed.
- S-ML performed comparably to M-ML in hip and knee joint kinematics in the sagittal plane and even outperformed M-ML in knee abduction/adduction in the frontal plane.
- Ankle joint angles measured by S-ML showed reduced agreement compared to the gold-standard marker-based system.

## Abstract

Background and Objectives: This study aimed to verify the validity of markerless gait analysis using both single-camera markerless system (S-ML) and multi-camera markerless system (M-ML) approaches by comparing them with a gold-standard marker-based system (MB). Materials and Methods: Sixteen healthy adults walked at their gait speed, and their gaits were simultaneously analyzed using three systems: S-ML, M-ML, and MB. Intraclass correlation coefficients were used to assess the reliability of the spatiotemporal parameters, and the root mean squared error (RMSE) was calculated to quantify the kinematic differences relative to the MB systems. Results: Both S-ML and M-ML demonstrated good-to-excellent reliability in spatiotemporal parameters, including step length, stance time, and gait speed, whereas stride length and swing time measured by S-ML revealed moderate reliability. In terms of joint kinematics, S-ML demonstrated a performance comparable to that of M-ML, particularly at the hip and knee in the sagittal plane. For certain parameters, such as knee abduction/adduction in the frontal plane, the S-ML demonstrated lower RMSE values than M-ML. In contrast, the ankle joint angles estimated using S-ML exhibited reduced agreement. Conclusions: In conclusion, markerless gait analysis can serve as an alternative to conventional gait analysis. However, certain parameters need to be improved.