Positional relationship between leg rotation and lumbar spine during quiet standing

Abstract

Healthcare professionals frequently evaluate spinal posture on visual assessment during the clinical examination. While this visual assessment of the spine has been shown to be unreliable, the use of a plumbline as to aid clinical visual assessment has also been reported. There is a "normal" sagittal contour that functions quite well in healthy people. It positions the head in space, it protects the neural axis, and it allows efficient, pain-free motion. Lumbar lordosis is routinely evaluated in most spine patients, but what constitutes a normal sagittal contour is less well defined. A key component of normal sagittal contour is lumbar lordosis. Changes in the lumbar lordosis frequently occur in pathological gait, usually in association with alterations in pelvic tilt, and commonly as a compensation for a limited range of flexion/extension at the hip joint. Recent investigations looked at the effect of hyperpronation on pelvic alignment in a standing position and supported the existence of a kinematic chain in healthy subjects, where hyperpronation can lead to an immediate shank and thigh internal rotation and change in pelvic position. While there is a wealth of research is available on the effectiveness of functional foot orthoses, the present investigation reports the effect of pronated foot position on the lumbar region of the back by employing an optoelectronic movement analysis system.