Biomechanical effects of traditional Chinese exercises on scoliosis: a combined finite element and surface electromyography analysis.

OBJECTIVE

To investigate the effects of two specific traditional Chinese exercise movements-"Lu Di" and "Jiu Gui Ba Ma Dao"-on spinal biomechanics and trunk muscle sEMG characteristics, elucidating their potential corrective mechanisms for idiopathic scoliosis.

METHODS

A Lenke type 1 scoliosis finite element model (T1-S1) was developed by applying mesh deformation techniques to a healthy adult spine model. Kinematic parameters of the spinous processes were acquired from 10 healthy subjects performing the two exercises using inertial sensors and applied as boundary conditions for the FEA. Vertebral and intervertebral disc stress distributions were analyzed under a fixed loading angle during the "Lu Di" movement. Concurrently, sEMG signals from the bilateral erector spinae and multifidus were recorded in patients with Lenke type 1 scoliosis during the exercises to evaluate muscle activation timing and inter-limb symmetry.

RESULTS

FEA demonstrated that complex movement loading induced favorable adjustments in stress distribution and deformation patterns, notably reducing disc stress on the concave side of the apical vertebra. sEMG analysis revealed that both exercises modulated trunk muscle activation levels and bilateral symmetry. They effectively increased force output in the convex musculature without inducing significant fatigue, while appropriately enhancing activation on the concave side.