The Japanese Orthopaedic Association proposed the term “locomotive syndrome” (LS) to define people at risk of requiring nursing care because of problems with their locomotive system. There is a need to develop simple methods to quantify motor performance and the early detection of LS. Sit-to-stand (STS) movements are a mechanically demanding task in everyday activities and represent motor performance. In the present study, we have developed a novel method to quantify STS movements (STS score) using ground reaction force and center of pressure data from the Nintendo Wii Balance Board (WBB). We investigated whether the STS score can predict LS.

The study enrolled 155 subjects aged over 65 years. Individuals were divided into three groups based on LS risk tests results. The subjects were instructed to stand up as quickly as possible on the WBB, and the STS score was calculated as the combination of the speed and balance indices. We also performed a timed up and go test and hand-grip strength test to evaluate the motor status.

There were significant differences in each test among the groups (Table 1).

The STS score significantly decreased with the severity of LS and thus could be used to assess LS in elder people.