Efficacy of Thoracolumbar Bracing in Spinal Immobilization: Precise Assessment of Gross, Intersegmental, and Segmental Spinal Motion Restriction by a 3D Kinematic System

Background Various diseases of the spine are treated by immobilization via orthoses, although detailed evidence on the efficiency of orthotic bracing remains elusive. The present study sought to investigate the impact of 3 different orthoses on spinal immobilization using 3-dimensional (3D) kinematic measurements. Methods Twelve healthy volunteers performed different motion tasks, including trunk flexion/extension and bilateral trunk bending. Movements were performed under 4 different conditions: 1) without orthosis, 2) while wearing a 3-point hyperextension brace (HB), 3) while wearing a custom-made semirigid orthosis (SO), and 4) while wearing a custom-made rigid orthosis (RO). Spinal motion was analyzed using a 3D optical motion capture system assessing regional, intersegmental, and segmental range of motion (ROM). Results Assessment of spinal motion was successfully accomplished in all subjects. Overall, orthoses significantly reduced spinal motion compared with no bracing. RO caused the greatest restriction of regional, intersegmental, and segmental spinal motion among all orthoses. For flexion/extension, the mean percentage decreases between T3 and L5 in full active ROM with HB, SO, and RO compared with no orthosis were 38%/30%, 48%/47%, and 51%/55%, respectively ( P ≤ 0.05). Lateral bending was impaired by 28%, 44%, and 70%, respectively ( P ≤ 0.05). Assessment of lateral bending revealed greater immobilization by SO and RO compared with HB ( P ≤ 0.05). Conclusions The present 3D kinematic system allows for precise assessment of spinal motion. Custom-made orthoses cause superior restriction on gross spinal motion compared “off-the-shelf” orthoses. If orthotic bracing is indicated, design, comfort, and patient compliance need to be carefully considered to guarantee successful therapy.