'RiceWrist' retrains motor skills after spinal-cord injury

Rice University is having great success with its prototype robotic device that, as a wearable exoskeleton, mimics a patient's joints from shoulder to hand.

Elizabeth Armstrong Moore
Elizabeth Armstrong Moore is based in Portland, Oregon, and has written for Wired, The Christian Science Monitor, and public radio. Her semi-obscure hobbies include climbing, billiards, board games that take up a lot of space, and piano.
Elizabeth Armstrong Moore
2 min read

Almost exactly a year ago, in April 2010, professional motocross rider Randy Childers sustained serious injuries after a crash in the last race of the day at Cowboy Badlands in West Beaumont, Texas.

He suffered broken ribs and a fractured wrist, but most seriously a crushed vertebra in his neck (C3) that required him to be airlifted to Houston, where surgeons inserted an artificial vertebra and fused two others together (C4 and C5) during a marathon operation that lasted 12 hours.

Today, the 24-year-old is the star in a single-patient trial of Rice University's RiceWrist robot, a wearable exoskeleton that mimics the joints from his shoulder to his hand.

After months of traditional physical therapy, Childers had recovered enough by October to walk (albeit slowly) into the basement lab at Rice and begin to use the RiceWrist, which is built to reconnect motor pathways in the brain through repetitive movement. After just two weeks, Rice Professor Marcia O'Malley says, Childers was doing most of the work himself.

Randy Childers works with an early version of the RiceWrist. Jeff Fitlow

The RiceWrist features a fully customizable "assist-as-needed architecture" so that a patient can do all the work of a prescribed task himself but, on reaching his limit, can be assisted or even fully guided. With Childers, a therapist sets the degree of assistance, but in the future the degree of assistance will be based on real-time performance assessment.

In late June, Childers will be flying to Zurich with O'Malley to present the results of the study at the IEEE International Conference on Rehabilitation Robotics.

"This is not just an exercise machine," O'Malley, director of Rice's Mechatronics and Haptic Interfaces Laboratory, said in a school news report. "We want the patients to move independently. When they're unable to complete a movement or reach the end of a workspace, the robot kicks in. But the literature supports the idea that there needs to be some intentional movement to really reap the rewards of rehabilitation."

That intention and desire to excel plays a big role in Childers' fast recovery, O'Malley stresses. "If you really want to reconnect those motor pathways, they need to have the intent. They need the brain thinking about moving and the limbs moving at the same time. That firing in the brain and the spinal cord leads to remapping."

Before it can gain FDA approval, the RiceWrist will be tested at the University of Texas Physical Medicine and Rehabilitation Motor Recovery Lab at Memorial Hermann's Institute for Rehabilitation and Research--the same facility where U.S. Rep. Gabrielle Giffords is recovering from a gunshot wound to the head.