Andrea Behrman PT, Ph.D.
Andrea Behrman PT, Ph.D., is an Associate Professor in Physical Therapy at the University of Florida. Her specialty is adult neurorehabilitation; for nearly 30 years she has studied walking function in people with spinal cord injury. Indeed, Behrman's clinical work has helped translate the basic science that defines the Reeve Foundation NeuroRecovery Network, of which she is assistant director. In March Behrman was honored with what she calls "the Oscar" of her profession: she was named a Fellow in the American Physical Therapy Association for her lifetime achievement. In the following article Behrman discusses her work, the NRN, and hope, with Foundation staffer Sam Maddox.
Where did your interest in neurorehab and recovery originate?
Behrman: Back in the early 1980s there was a shift in the spinal cord injury population; because of better emergency management there were many more incomplete injuries. These people were walking more, moving their toes more, etc. It seemed to me that we as therapists needed to find ways to better encourage their greater potential. Textbooks did not address this potential, but focused predominantly on rehabilitation for individuals with complete injuries. My first two patients as a therapist included one with a complete SCI and one with an incomplete SCI. They still guide my thinking today.
What was a 1980s therapist doing?
Behrman: Twenty years ago in rehab, our only goal was to strengthen and build endurance for every muscle still under voluntary control. Basically, we taught strategies – compensatory strategies – new ways for eating dressing, transferring, moving around in the community, using a wheelchair, etc. The concept was that patients have to compensate for weakness. We have moved, or are starting to move, from compensation to taking advantage of own biology to recover function – that's a huge shift, and it's still going on; it will characterize rehab for the next 20 years.
What is behind activity-based therapy?
Behrman: Basic scientists wanted to understand the nervous system and how it controls movement and, in particular, walking. In animal experiments they showed that the spinal cord makes a contribution to the control of locomotion; the cord has its own circuitry apart from the brain that can generate a stepping pattern. When a cat with a severed cord (a complete injury) is placed on a moving treadmill with its body weight supported, it can be trained to walk with repetition and practice. Now, that cat cannot jump off the treadmill and go climb a fence or chase mice; it still needs an intact connection from the brain to the spinal cord to walk at will. The activity refers to the practice of the specific task of walking and the nervous system's response in generating muscle activity (trunk control and stepping) below the level of the lesion.
So the spinal cord is not a passive set of nerve fibers?
Behrman: We used to believe the brain would issue the executive command to walk, that the spinal cord was more like a telephone cable and simply carried brain commands to the muscles. It turns out the spinal cord is not just a cable but actually is, to some degree, "smart." If the sensory information that is provided to the spinal cord looks like walking, the spinal cord can recognize this information and respond by generating a stepping pattern of muscle activity. If you repeat this patterning, in this case with guided stepping on a treadmill, the individual can sometimes regain locomotor function. The therapy is not readily available in most clinics today; it is however the centerpiece of the NRN.
We hear dramatic stories. You published such a report last year, right?
Behrman: A young boy with a gunshot wound at the C6/7 level was referred to us. He was four and a half and had been in a wheelchair for 16 months. By every clinical measure, by every standard reha bilitation protocol, he was non-ambulatory and it was predicted that he would not walk. We started to train him on the treadmill. After 20 sessions we really had no progress; we were starting to get frustrated. Personally, I had to fight the urge coming from the standard clinical data, from the facts we had, that said this wouldn't work. That is so ingrained in us. After a few more sessions we could elicit a spinal step but it was not willful. I turned to the boy and asked, "Can you get it going on your own?" He shook his head no. But just then, he took 15 steps! Now he's ambulatory full time, though he can't walk backwards or side to side, and his balance is not good. He will be back in our clinic this summer to see how much further he can go with booster sessions of training. What we learned from this is what is possible. All tests and all standard thinking said that he would not walk. But it was possible in this child given the right training environment, experience, practice, and family support.
Someday shouldn't you know before treatment whether a person will benefit?
Behrman: What we need are better assessments – what could we have measured to know what this boy had to work with? We're still trying to learn how to tell which people will benefit from locomotor training, which will not, and what sort of training intensity is needed, within what time frame, for the best outcome. We also need a better ruler to measure the outcome itself; the current methods of evaluation are based on compensation for lost function and don't take into account recovery of function.
Walking isn't the mantra, though.
Behrman: Right. There are other health benefits that come along with locomotor training, including cardiovascular health or the ability to control your trunk better whether sitting or standing. And a successful locomotor training or outcome may mean that after training the individual walks more like he or she did prior to spinal cord injury. Generally, people also see gains in their daily, functional mobility and the amount of time they stand and walk. They may still require some assistive device because of the community they live in, for example, for uneven terrain. Not every one ambulates, of course. Will every type of injury benefit? Not everyone will walk, however, everyone is likely to show some benefit.
What is your role at the NRN?
Behrman: The NRN, funded through a cooperative agreement with the Centers for Disease Control and Prevention, is a collaboration between neuroscientists, such as Susan Harkema, clinicians, physicians, SCI program directors, and clinical scientists, such as me. The program hopes to form a road map to recovery and improved quality of life via activity-based therapies, validated by the evidence and able to be replicated anywhere. My primary responsibility is to standardize the locomotor therapy across the seven NRN clinical sites and to advance the therapeutic program at each site. We want to make sure we provide the same therapies to acquire standard data and standard outcomes to evaluate the program's effectiveness. We teach therapists techniques and training protocols and hope thereby to foster wise, evidencebased clinical decision-making. I also chair the Pediatrics Committee within NRN that aims to provide locomotor training to children and evaluate outcomes.
What advice would you give to somebody with spinal cord injury or a stroke?
Behrman: Stay at the best level of fitness that you can. You never know what advance is coming down the road. Persons who have joint and muscle flexibility and are more fit will be in a better position to accept the opportunity to pursue whatever therapy may be available in the future. How does science offer us hope? Behrman: Scientific evidence helps direct us to make good decisions for patient care and rehabilitation — science directs clinical practice. By translating the basic principles of the stepping function in the spinal cord to a therapeutic intervention, it changed our mindset about the potential of the nervous system and our assumptions of what a person can and cannot do. Those assumptions give us hope – real hope for changing outcomes for people with spinal cord injuries.