Change of Spinal Curvature in Stepping on a Stool

[Purpose] We investigated the changes in thoracic kyphosis and lumbar lordosis angles when a foot was placed on stools of different heights. [Subjects] The subjects were 13 healthy women (21.7 ± 3.8 years) working at a medical university. [Method] We compared the changes of the kyphosis and lordosis angles of the subjects with one foot placed on stools, 10, 20 or 30 cm in height. [Results] Significant decreases in the lumbar lordosis angles where found between the postures of quiet standing and stepping forward, and one-leg stool-stepping at heights of 20 and 30 cm. No significant differences were found for the thoracic kyphosis angles. [Conclusion] The results suggest that one-leg stepping on a 20-cm high stool could become an index in ADL guidance aiming to reduce lumbar lordosis for patients with low-back pain.