The Heisenberg Uncertainty Principle states that it's impossible to accurately measure the position of a subatomic particle because the radiation used in measurement actually alters the position. In a similar way, until a few years ago, physicians who wanted to measure gait patterns often had to strap such cumbersome equipment to their patients with handicaps or leg injuries that the gait itself changed.
Development of lightweight sensors and computer technology has allowed more accurate assessment of gait in the past few years. But, until recently, only large teaching hospitals could afford this sophisticated and expensive equipment. Now, however, relatively simple and affordable microcomputer systems are allowing smaller clinics, departments, and even individual practitioners to assess gait objectively.
At the recent Fourth World Congress of the International Society for Prosthetics and Orthotics in London, several of these systems were discussed. One, a portable microcomputer system developed at the University of Capetown