Watching Cole throw his arms and shoulders into playing a video game, you might never guess that he suffers from a severe muscular disease. But he does. Cole has Duchenne muscular dystrophy (DMD), a genetic disorder that results in progressive muscle degeneration. DMD patients, almost all of whom are boys, seldom live beyond early adulthood, and most are wheelchair bound by their early teens.
Dedicated medical researchers are testing a host of experimental treatments that might slow or even halt the disease’s otherwise relentless progress. Currently, most clinical trials limit admission to patients who can walk unassisted for six straight minutes. The distance the boy can walk in six minutes is used as a baseline; if the distance increases during the course of the treatment, it indicates that the experimental therapy is having a positive effect.
Unfortunately, the six-minute-walk requirement rules out a lot of boys who still have considerable upper-body strength but cannot walk the requisite six minutes. Physical therapists Linda Lowes and Lindsay Alfano at Nationwide Children’s Hospital are working to get more boys accepted into clinical trials by developing a simple, reliable measure of upper body abilities that could be used as an alternative to the walk test. And Kinect for Windows v2 is playing a critical role in their efforts.
ACTIVE-seated uses Kinect for Windows to measure upper-body muscle strength in boys with
Duchenne muscular dystrophy.
Lowes, Alfano, and their colleagues have devised a Kinect-enabled video game in which seated DMD patients control the action by vigorous arm and shoulder movements. Called ACTIVE-seated (the acronym stands for Ability Captured Through Interactive Video Evaluation), the game not only measures upper-extremity abilities but does so while motivating the patient to perform his best.
ACTIVE-seated uses Kinect for Windows’ capabilities to record accurate data on the patient’s upper-extremity reach and range. The gamer—that is, the patient—is seated at a special table, some distance from a video monitor that displays the game. Taking advantage of the body tracking options in the Kinect software development kit (SDK), the researchers use the Kinect sensor’s infrared camera to track the position of the patient’s head, trunk, and arms as he plays the game. By identifying points on the head and sternum, both shoulders, and each arm, the researchers can measure the patient’s maximal upper-extremity movement in three planes: horizontal (left and right), vertical (table top to overhead), and depth (forward toward the camera).
Players can choose between two different games based on their interests. Both games were developed with input from the boys, who obviously know what pre-teen males enjoy. They overwhelmingly agreed that something “gross” would be best. Based on this recommendation, one game involves a spider invasion, in which the boys squish the spiders, which crunch realistically and ooze green innards. The second game, designed for the more squeamish, involves digging for jewels in a cave.
“You should see the faces of new patients light up when they hear that they’re going to be playing a video game instead of undergoing another boring set of tests,” says Lowes. The allure of a video game increases the patients’ motivation, which, in turn, improves the reliability of the results. When asked to perform uninspiring tests day after day, boredom sets in, and the desultory results don’t measure true functional ability. But when it comes to playing a video game, boredom isn’t a problem.
ACTIVE-seated is currently in testing, and a recent study of 61 DMD patients found that scores in the game correlated highly with parent reports of daily activities and mobility. Lowes and her colleagues are hopeful that these results will help convince the U.S. Food and Drug Administration to use the game as an alternative test for admission to DMD clinical trials.
The Kinect for Windows Team