Physical therapists in California are using computer games with motion capture technology to help paralysis patients increase their range of motion during exercise. Use of the games is still in an experimental phase but both therapists and their patients are reporting positive results.

"My posture improved because you have to sit up up right in order to be able to reach properly. My endurance has improved, and also my reaching ability and range of motion because they do force you to reach out a little more than you're used to comfortably," he said.

In recent years video games have emerged in many fields of medicine as an effective tool for treatment, either as a distraction for recovering burn vicitms or an alternative for anesthesia in minor surgery.

The games Pizarro is using were developed by a research team at the University of Southern California's Institute for Creative Technologies (ICT). Led by physiotherapist Belinda Lange, the team is developing games that incorporate motion and gesture sensing technology that responds to physical movement from the patient. As patients become absorbed in the game, they forget that they are actually working. They become competitive, and as a result, intensify their efforts to improve.

"We're leveraging the technologies behind the current video games, so using something like the Microsoft Kinect that can track people in a very low cost way and without having to hold any devices. But the key difference is that we can tailor our game to be usable by a wider range of people. People with different levels of ability should be able to play the same game but play at their appropriate level of challenge," said Lange.

Although still in pilot phase, the games are already being used at several facilities in California and Germany, including Precision Rehabilitation in Long Beach. Therapists at the clinic record patients' sessions, replay and discuss them frame by frame, and use the information to set precise goals.

David Kaarchem, a former software engineer who suffered a stroke 33 months ago, was one of the first patients to test the game. He helped the ICT team through their development process and he says the work is bearing fruit.

"Today is major. I got to use my left arm really for the first time. My only complaint is that I want it faster and sooner."

Lange's team is working to improve the games and raise the level of challenge to keep users interested. They are also studying how these games could be used at home, to give patients even more opportunity for practice and rehabilitation.