Evaluating the immobilization effect of spinal orthoses using sensor-based motion analysis

Introduction External spinal orthoses are commonly used in treating spinal disorders. The purpose of a spinal orthosis is to relieve pain and reduce spinal motion. Despite the widespread use of spinal orthoses, evidence of their efficacy is lacking, and there is no literature comparing different types of orthoses with regard to objective measurements of the immobilization effect on the thoracolumbar spine. Aim The aim of this study was to evaluate and compare movement reduction and comfort of four types of thoracolumbar orthoses on the normal motion using inertia sensor-based motion analysis (IMA). Methods Ten healthy volunteers were asked to perform five tasks of daily living without an orthosis and with four different types of orthoses. Motion analysis was performed using IMA. Comfort and subjective immobilization were analyzed by a questionnaire. Results All gait parameters were comparable in the different conditions. During the sit-to-stand (STS) test, the maximum angular bending rate was significantly impaired by all orthoses compared with the unbraced condition. During the block-step test, significant differences were found in pelvic obliquity for braced conditions. The bending angle was significantly reduced during the flexion and extension test for all orthoses. Wearing an orthosis showed significantly larger pelvic obliquity during latero-flexion compared with the unbraced condition. In a subjective analysis using the questionnaire, the bandage scored best, and the Jewett scored worst in comfort and movement restriction. Conclusions All orthoses influence spinal movement during several daily tasks as was shown by IMA. The most rigid orthoses provided the most movement restriction, but simultaneously scored worse in comfort. The choice for a certain brace should be based on individual patient characteristics and diagnosis because of the experienced differences in impairment and comfort.