Exercise and New Function

• Fact sheet on FES bicycles and treadmill (locomotor) training

Christopher Reeve demonstrated to the world that he had recovered some movement and sensation. While he could not walk, did not regain bowel, bladder, or sexual function, nor could he breathe without a ventilator, his limited recovery was significant. The scientific literature on spinal cord injury predicts that most recovery will occur in the first six months after injury and that it is generally complete within two years. Reeve’s recovery, coming five to seven years after his injury, defies these medical expectations and had a dramatic effect on his daily life.

Why did he get better so long after his injury? Reeve believed his improved function was the result of vigorous physical activity. He began exercising the year he was injured. Five years later, when he first noticed that he could voluntarily move an index finger, Reeve began an intense exercise program under the supervision of Dr. John McDonald at Washington University in St. Louis.

Reeve included several activities in his program. He used daily electrical stimulation to build mass in his arms, quadriceps, hamstrings and other muscle groups. He rode a Functional Electrical Stimulation (FES) bicycle, did spontaneous breathing training and also participated in aquatherapy. In 1998 and 1999, Reeve underwent treadmill training to encourage functional stepping.

Reeve and Dr. McDonald suggested that these activities may have awakened dormant nerve pathways. The fact is, however, that it is not possible in a single experiment to know just what did occur in Reeve’s nervous system. To be sure, his recovery may have been related to exercise. Dr. McDonald and other researchers and clinicians caution not to over-interpret Reeve’s results. Clearly, not all people with paralysis would benefit from a similar program.

Said McDonald in the Journal of Neurosurgery – Spine, “Although we cannot conclude that the activity-based recovery program produced the functional benefits, we believe it was responsible for the physical benefits.”

It is true for any of us: exercise is related to better health. Because there are few, if any, negative side effects of exercise, even people who don’t experience recovery in the way that Reeve did are likely to improve their well-being. For Reeve, a high quad on a ventilator, improved health was the single most important benefit of his exercise and therapy program.

Reeve’s participation in exercise was motivated by the well-known benefits on cardiovascular function, muscle tone, bone density, etc. Indeed, he had fewer medical complications such as bladder and lung infections. Before 1999, Reeve frequently required hospitalization – he had a total of nine life-threatening complications and required almost 600 days of antibiotic treatment. After 1999, he was rarely hospitalized, had only one serious medical complication, and needed only 60 days of antibiotic treatment. These improvements in his health boosted Reeve’s emotional well-being and enabled him to commit to a variety of work projects knowing he could give them his uninterrupted attention.

If Reeve’s recovery of function was due to the exercise, it was a wonderful side effect. Now, scientists are undertaking detailed studies and working with large numbers of people in centers across the country to give them the chance for similar benefits.

Christopher Reeve’s experience is an example of what can happen when one refuses to accept the “get used to it” dogma. Although it is not clear what caused his recovery, his improvements in function provide a source of hope and inspiration for others.

Reeve was a strong advocate for making FES technology more widely available. “I have the staff and the equipment,” he said. “But what I really hope comes out of my experience is a paradigm shift in the way insurance companies do business. If insurance companies would pay for proactive therapy and equipment they would save money keeping people like me out of the hospital. People with lower level injuries would get up and get out of their chairs. It’s a win-win proposition.”

Here is a rundown on the various activities that were in Reeve’s exercise program: (Note: Before considering participation in advanced rehabilitation therapies, such as FES or treadmill training, it is important to be evaluated by one’s own physician to ensure that the therapies are appropriate and safe.)

Functional Electrical Stimulation (FES):

Reeve did one hour of exercise at least three times a week on an FES bicycle. This technology allows persons with little or no voluntary leg movement to pedal a stationary leg-cycle called an ergometer. Computer generated, low-level electrical pulses are transmitted through surface electrodes to the leg muscles; this causes coordinated contractions and the pedaling motion.

FES bikes are not new; they have been on the market for over 20 years. Moreover, FES systems have been deployed in research centers throughout the world for the last several years.  Here in the U.S., there are a couple of companies currently producing the bikes. Therapeutic Alliances, Inc., one of the oldest manufacturers, makes  the Ergys 2.  A newer company called Restorative Therapies, Inc. offers the RT300-S which is operated straight from the wheelchair eliminating the need for transfer. (Electrologic, original maker of the StimMaster Orion, has gone out of business.)

FES bikes are also not cheap – they are in the range of $15,000. Some insurance companies have reimbursed for units. There are bikes available in some community settings, at health clubs and rehab clinics. See below for contact information; the Paralysis Resource Center has a list of clinics that use FES bikes.

The first step is to choose a bike that is mechanically sound. All the electronics are upgradeable from the manufacturers. Each bike has a program cartridge set up for the specific needs of each rider, including run times, resistance, etc. A prescription is needed to get the cartridge. For safety reasons, it’s not recommended that FES bike riders use another’s cartridge.

Abundant medical literature documents the effectiveness of FES to increase muscle mass and improve cardiopulmonary function. There are studies that also link FES to a reduced frequency of pressure sores, improved bowel and bladder function and decreased incidence of urinary tract infections. Until now, there have been no reports in the literature linking FES to functional improvements of the sort Reeve experienced.

According to Dr. McDonald, the FES bike can be more useful than for just building muscle mass. “We propose to use them for a totally different reason -- to promote regeneration and recovery of function. We now have data demonstrating that [FES] activity can enhance regeneration in animals and is associated with recovery of function in humans.”

Treadmill or locomotor training, also known as weight-supported ambulation:

Locomotor training is a rehabilitation approach that has been emerging over the last decade. It involves a kind of activity-triggered learning whereby practicing a series of specific movements (in this case, stepping) triggers the sensory information that somehow reminds the spinal cord how to initiate stepping.

Treadmill training uses repetitive motion to teach the legs how to walk again. A paralyzed person is suspended in a harness above a treadmill; this reduces the weight the legs will have to bear. As the treadmill begins to move, therapists move the person’s legs in a walking pattern. The theory that drives the work is that paralysis causes “learned non-use” of muscles. But the injured nervous system may be “plastic,” that is, capable of recovery when certain conditions, including the patterned neural activity that accompanies treadmill walking, are optimized.

Research from the University of California at Los Angeles and in Germany, Switzerland and Canada, notes that the spinal cord itself appears to act like a small brain and is thus capable of controlling ambulation. The spinal cord makes many routine decisions about the correct way to walk. When a paralyzed person is retrained to walk, both the brain and spinal cord figure out new ways to do it.

Many people with paralysis, regardless of time elapsed since onset, have improved their walking after receiving locomotor training. The level of recovery is different for each person, although almost all those with incomplete injuries showed gains.

It is important to understand, however, that locomotor training is an evolving procedure and may not help everyone to walk better. Scientists, physicians and therapists are still learning the best way to train and which patients can benefit the most. While locomotor training is part of the rehab experience for many Europeans, there is little expertise on how to do it and it is not widely available in the U.S. This is due to change soon as the commercialization of the technology moves forward.

As treadmill units filter out into the community, it is important for people to recognize that a locomotor training program must include highly trained therapists to work with patients. Maximizing a patient’s ability to step after injury depends to a very large extent on the skill and precision with which the therapists deliver locomotor training.

Aquatherapy:

Christopher Reeve demonstrated the ability to move his legs and arms in a pool. The effects of gravity are greatly reduced in water so that small body movements can be more easily detected and therapists can determine a person’s maximum ability to move without the full resistance of gravity. Also, when people are beginning to recover movement, water makes practice easier. When time permitted, Reeve did aquatherapy once a week for approximately two hours.

Bone density treatment:

Since people with paralysis don’t typically put weight or pressure on their bones, they tend to lose bone density and often develop osteoporosis. With drugs and exercise on the FES bicycle, Reeve’s osteoporosis was reversed to normal bone density.

FES Resources

Therapeutic Alliances, Inc. makes and markets the Ergys 2 and supports the older Regys bikes. Contact the company at 937-879-0734 or visit the Internet site, www.musclepower.com.

Restorative Therapies, Inc. was founded by one of the leading proponents of restorative therapy, Dr. John McDonald, who supervised Reeve's  rehabilitation program. The company recently introduced the RT300-S. Pedals with leg guides are accessed directly from the wheelchair so no transfer is required.  Phone them toll free at 1-800-609-9166 or visit the Internet site,  www.restorative-therapies.com.

A list of clinics and facilities that use FES bikes is available from Paralysis Resource Center Information Specialists.

For information and background on FES and its other applications, contact an FES Center near you.   Most have websites and staff that can assist you, such as  the Cleveland FES Center.

Treadmill or locomotor training resources:

The UCLA group has developed a treadmill training being manufactured by Robomedica, Inc . The advantage of this system is the depth of expertise in the development team, led by prominent researchers Reggie Edgerton and Susan Harkema. This is the unit Reeve used. It has also been used extensively in clinical trials for spinal cord injury in the U.S. and Canada. Contact Robomedica at 949-788-0525 or visit the Internet site http://www.robomedica.com/

Mobility Research, based in Tempe, AZ, has been selling a harness and treadmill training set up for several years. The LiteGait system can be rented or purchased directly (a pediatric model is $2250; various other models are priced up to $10,500, plus the treadmill, at $2950). The company says it has many stories of paralyzed users getting function back. Its treadmill trainers are available around the U.S. Contact them at www.litegait.com or toll free 1-800-332 WALK (9255).

Other locomotor systems are coming to the market. The Lokomat, from Switzerland, is being tested at the Rehabilitation Institute of Chicago and the National Rehabilitation Hospital in D.C. The Miami Project to Cure Paralysis also has a Lokomat. The device is described as an exoskeleton (an external skeleton) with robotic joints at the hip and knee to guide the user’s legs as they step along the treadmill. The technology is intended to reduce the need for some of the therapists during a training session. See the device at http://www.hocoma.ch (click on the English version).

HealthSouth, the big rehab center chain, has introduced the AutoAmbulator, a harness and treadmill rig inspired by a visit to UCLA’s treadmill program several years ago. The company rolled the product out in 2003, beginning at their inpatient rehab facilities. Contact www.autoambulator.com for more.

Several clinical trials examining the effects of treadmill training are currently underway throughout the U.S.  Among them are a few being conducted by the Department of Veterans Affairs.

One, in Cleveland, is enrolling people who have had a stroke; part of the trial will also involve neuromuscular stimulation. Contact Janis Daly, Ph.D., 216-791-3800, jjd17@case.edu.

The VA Rehabilitation Research and Development Service is also enrolling people who have had a stroke in a Houston trial of treadmill training. Contact Elizabeth Protas, 713-794-7117, lim.peter@houston.va.gov

Another trial, sponsored by the National Institute of Child Health and Human Development (NICHD), is evaluating whether body weight support (BWS) gait training is more effective than conventional rehabilitation therapy in improving walking ability in patients with spinal cord injuries.  The study is also comparing treadmill-based training with overground-based training.

Subjects must have spinal cord injuries at or above the T10 spine.  In addition, chronic injuries need to be at least one year old prior to the start of training, or two to eight months old for subacute injuries. Contact Blair M. Calancie, 305-585-8347, bcalancie@miamiproj.med.miami.edu

For more details on these and similar clinical trials, see http://clinicaltrials.gov -- type the word treadmill in the search box.