Lumbar braces are often prescribed for acute and chronic low back pain patients, however, few patients use the brace ordinarily for the restriction of the lumbar motion due to rigidity of lumbar brace.

To overcome this issue, we have developed the lumbar brace using Ti-Ni shape memory alloy. As a preliminary study for the effect of the brace with SMA, the mechanical tests to determine the mechanical properties concerning Ti-Ni shape memory alloy (SMA), and the electromyography (EMG) measurement of volunteers were performed in this study.

In results, SMA showed appropriated superelasticity, and the brace with SMA reduced the EMG activities of trunk muscle in lumbar motion. Furthermore, the volunteer's feeling of pressure by brace also was improved significantly. Present study indicated the lumbar brace using SMA has the benefit effects to stabilization of the spinal muscle and de-restriction of the lumbar motion.