Authors

  1. Larsen, Deborah S. PT, PhD, FAPTA

Article Content

While I was a child at the time of NUSTEP, it is likely that I received a different education in my physical therapy baccalaureate program as a result of that conference. Our curriculum included coursework on motor development and the facilitation approaches, overlaid on a foundation of physiology and anatomy; all critical components of the NUSTEP conference. However, there was little information on motor learning or motor control, which would be the emphasis of II STEP.

 

I started my academic career just after the II STEP conference was completed. The compendium became my text, from which to develop my first class on the neuroscience of motor control, and subsequently an advanced course in the same for practicing PTs who were pursuing their advanced master's degree. The words of Horak and colleagues1 moved our treatment focus away from impairments (eg, spasticity), the hierarchical model of motor control and the neurofacilitation models of Bobath, Brunnstrom, Rood, and PNF and toward motor learning treatment models, a dynamic system model of motor control, and function. However, the recommendations of these insightful physical therapy leaders were largely predicated on studies of nonpatient populations or animal models, and highlighted an urgent need for research to examine motor learning principles within patient populations. Thus, II STEP not only enlightened my teaching but also targeted my research agenda and that of numerous others toward the evaluation of motor learning principles in the treatment of patients with neurologic conditions.

 

Notably, as the foundation for neurologic treatment approaches transitioned to motor learning principles, the concept of treatment-induced neuroplasticity emerged, and the time period between II STEP and III STEP saw the rapid escalation of research on the relationship between treatment paradigms and neuroplasticity. Like so many others, I began to look at functional magnetic resonance imaging (fMRI) and then, transcranial magnetic stimulation (TMS) to map neural changes poststroke related to novel treatment paradigms (eg, constraint-induced movement therapy, CIMT), followed by diffusion tensor tractography measurement of white matter (DTT), finding a return to more typical activation patterns posttreatment2 with an expansion in the motor map for the hand3 that was dependent on white matter integrity.4 The development of advanced imaging techniques afforded many researchers new opportunities to assess neuroplasticity in humans, not just in animal models, so there was literally an explosion of research in this area. Thus, the 15 years between II STEP and III STEP constituted a critical phase in the maturation of physical therapy research, which informed physical therapist education, transforming curricula at the same time that educational preparation transitioned from the baccalaureate to the masters to the doctorate. Although these parallel changes in our profession may not have a causal relationship, they relate to our profession's evolution from dependency on others for research to inform physical therapy treatment as well as to direct our treatment choices, to an evidence-based profession with an expanding degree of autonomy in practice.

 

III STEP introduced us to (1) the International Classification of Functioning, Disability and Health (ICF), emphasizing the need to target activities and participation in treatment (WHO), and (2) the enablement model, emphasizing the need for patient involvement in goal determination and treatment choice. It also provided a showcase for the amassed evidence on motor learning-based treatment approaches and neuroplasticity. Although the highlighted treatment approaches demonstrated that motor learning principles translated well to the treatment of neurologic conditions and were effective in stimulating neuroplasticity, we still did not have consensus on appropriate dosing, timing, and the key components of effective treatment methods, largely due to the extreme variability in patient populations. For those of us in academia, the conference again gave us marching orders to (1) revise our curricula to include the emphasis on the ICF and enablement models as well as the growing evidence for treatment-induced plasticity with inclusion of information on imaging and other methods of measuring plasticity; and (2) target our research on the critical components of effective treatment methods.

 

The next decade was filled with the outcomes of a number of large-scale multicentered clinical trials, including (1) SCILT-Spinal Cord Injury Locomotor Training5; (2) EXCITe-Extremity Constraint-Induced Treatment Evaluation6; and (3) LEAPS-Locomotor Experience Applied Post-stroke.7 These trials revealed that high-intensity practice achieved significant improvements in both chronic,5 subacute,6 and acute patient populations5,7 but that the method of treatment (ie, treadmill training vs overground gait training or home-based exercise training) might not be that critical. However, they also suggest that the rate of change might be affected by the timing of treatment (early vs late).7,8 For some, these were called failed trials, because the primary hypothesis was not supported; however, the findings all indicated that high-intensity physical therapy improved function for neurologic conditions and far exceeded the usual and customary care currently provided to those with neurologic insults.

 

IVSTEP, as with the conferences that preceded it, served to shake the foundation of physical therapy practice for neurologic conditions across the lifespan. Much of the critical information focused on the nonresponders of clinical interventions and clinical trials, emphasizing the individual nature of the manifestation of neurologic insults and necessitating research that captures this individualization with personalized therapeutic approaches and embraces more flexible protocol designs (eg, single-subject study designs). The last decade's focus on multicentered trails has resulted in a gain of knowledge but has focused us away from the individual and toward a group mean effect. Yet, the presentations at IVSTEP served to focus us back on the individual.

 

Further, the IVSTEP presentations provided evidence that we have much to learn about effective treatment methods; dose-response relationships; the influence of genetics, epigenetics, environment, and motivation on treatment outcomes; and how best to incorporate client goals into treatment and outcome measurement. For example, the dose-response study, conducted by Lang et al9 and presented at IVSTEP, indicates that more may not always be better, so there are limits to the potential for improvement based only on increasing levels of practice intensity (eg, repetitions). Notably, the lowest repetition rate for this trial was much higher than that typically seen in a standard therapy session and tenfold the rate, reported by Lang's lab in 2010, for the average number of repetitions per therapy session in typical poststroke programs.10 Additionally, a number of the presentations at IV Step noted that participant-reported activity levels acquired following intervention often diverge from measurements acquired via activity monitors. Again, these findings highlight a key message of IVSTEP: patient inclusion in therapeutic goals and outcome measurement are critical for the effective analysis of interventions and to effectively achieve improved participation for individual participants.

 

Lastly, the conference expanded our knowledge on the role of physical fitness for primary and secondary prevention of the sequelae of neurologic conditions, providing some level of neuroprotection for preventing some conditions (eg, dementia11) or delaying symptom onset (eg, Huntington's12) as presented by McGough and Quinn at the conference; for those living with a neurologic condition, it can minimize the secondary effects of inactivity postinsult.13 This should be a topic for greater levels of research over the coming decade to explore how physical therapists can be more involved in early-stage treatment protocols for people diagnosed with a progressive neurologic disorder as well as developing fitness protocols for those with neurologic insults (stroke, traumatic brain injury).

 

Once again, I find myself revitalized by the presentations and discussions of IVSTEP and energized to incorporate these critical components into my next research project. I find myself concerned that, as I approach my 40th year as a physical therapist and my 30th as a researcher, I will have to yield much of what needs to be done to the next generation of physical therapy scholars. However, having participated in this conference and witnessed the enthusiasm of those early in their careers, I know that we will continue to expand our knowledge, improve the education of our physical therapy students, and enhance the outcomes of our interventions for those with neurologic conditions throughout the lifespan. I cannot wait to see what we will know by the time VSTEP rolls around.

 

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