# Influence of Main Thoracic and Thoracic Kyphosis Morphology on Gait Characteristics in Adolescents with Idiopathic Scoliosis: Gait Analysis Using an Inertial Measurement Unit

## TL;DR

This study shows how spinal curvature in adolescents with scoliosis affects their gait stability and symmetry, using motion sensors to measure trunk movement.

## Contribution

The study introduces a novel analysis of how specific spinal deformities correlate with gait patterns in AIS patients using IMU technology.

## Key findings

- The main thoracic curve positively correlates with mediolateral gait stability in AIS patients.
- Thoracic kyphosis negatively correlates with mediolateral trunk acceleration in specific quadrants.
- Right-convex thoracic curves cause leftward center-of-gravity shifts, impacting gait stability.

## Abstract

What are the main findings?
In patients with adolescent idiopathic scoliosis (AIS), the main thoracic (MT) curve showed a positive correlation with mediolateral gait stability, whereas thoracic kyphosis (TK) showed a negative correlation.A gait symmetry analysis revealed distinct correlations between spinal curvature and mediolateral trunk acceleration across different quadrants.

In patients with adolescent idiopathic scoliosis (AIS), the main thoracic (MT) curve showed a positive correlation with mediolateral gait stability, whereas thoracic kyphosis (TK) showed a negative correlation.

A gait symmetry analysis revealed distinct correlations between spinal curvature and mediolateral trunk acceleration across different quadrants.

What is the implication of the main finding?
Patients with AIS who have right-convex MT curves may experience a leftward shift in their center of gravity, thus affecting gait stability.A comprehensive understanding of the relationship between spinal deformities and gait patterns can inform the development of targeted rehabilitation strategies for patients with AIS.

Patients with AIS who have right-convex MT curves may experience a leftward shift in their center of gravity, thus affecting gait stability.

A comprehensive understanding of the relationship between spinal deformities and gait patterns can inform the development of targeted rehabilitation strategies for patients with AIS.

This study examined the relationship between spinal morphological changes and gait characteristics in patients with adolescent idiopathic scoliosis (AIS) using inertial measurement unit (IMU) analysis. Twenty-three female patients with AIS scheduled for corrective surgery underwent a preoperative gait analysis using an IMU positioned at the third lumbar vertebra. Gait stability indicators were calculated, including root mean square (RMS) values for mediolateral (RMSx), anteroposterior, and vertical components. Peak mediolateral components in four coronal plane quadrants were also analyzed. Relationships with the main thoracic (MT) curve, the thoracolumbar (TL) curve, and thoracic kyphosis (TK) were assessed using Spearman’s rank correlation. The MT curve is positively correlated with RMSx, whereas TK exhibited a negative correlation. Gait symmetry analysis revealed a positive correlation between the MT curve and peak mediolateral trunk acceleration in the second (left upper) quadrant, and negative correlations for TK in the first (right upper) and fourth (right lower) quadrants. Patients with AIS who have right-convex MT curves demonstrated leftward center-of-gravity shifts, although reduced TK limited this compensatory mechanism. These findings may inform the development of rehabilitation strategies for AIS.