NRN study highlights

Key findings on the impact of activity-based therapies

Research published in the September 2012 edition of the Archives of Physical Medicine & Rehabilitation confirmed that therapies like locomotor training trigger the body’s repair process, leading to enhanced mobility and health.

These findings further emphasize the importance of the NeuroRecovery Network (NRN) to develop and expand access to therapies that promote functional recovery, as well as improve the health and quality for individuals living with spinal cord injury and other physical disabilities.

The below highlights were aggregated from 11 peer-reviewed papers that were featured in the Archives based on data from 296 participants at seven NRN sites.

Basic Concepts of Activity-Based Interventions for Improved Recovery of Motor Function After Spinal Cord Injury

(Roy, RR, Harkema SJ, Edgerton, VR)

• The automaticity within the neural networks that control locomotion and the degree to which it can occur without conscious input from the brain is striking.
• This is possible in large part by the sensory input from the periphery providing a precise representation of the neuromechanical state of the locomotor apparatus to the spinal cord circuitry.
• This neural substrate provides the bases for step training therapy designed to facilitate recovery of locomotor function after a severe spinal cord injury.

Establishing the NeuroRecovery Network (NRN): Multisite Rehabilitation Centers That Provide Activity-Based Therapies and Assessments for Neurologic Disorders

(Harkema SJ, Schmidt-Read M, Behrman AL, Bratta A, Sisto SA, Edgerton VR)

• The Reeve Foundation NeuroRecovery Network (NRN) comprises seven clinical centers that provide standardized activity-based rehabilitation that is supported by scientific and clinical evidence. The therapies are robustly evaluated by taking measures related to function, health and quality of life.
• The NRN brings together scientists, physicians, physical and occupational therapists and hospital administrators to design the most effective and cost efficient clinical model.

Balance and Ambulation Improvements in Individuals With Chronic Incomplete Spinal Cord Injury Using Locomotor Training–Based Rehabilitation

(Harkema SJ, Schmidt-Read M, Lorenz D, Edgerton VR, Behrman AL)

• Recovery of walking and balance can occur even years after injury in people with incomplete spinal cord injury with rigorous locomotor training. Improvements occurred in 88% of the patients evaluated
• Even those with more severe injuries who are classified as AIS C made improvements. Locomotor training is a rehabilitation strategy that activates the nerves and muscles below the injury level with the goal of recovering the ability to do tasks as close to before the injury as possible.
• The walking and balance measures vary widely in people with incomplete spinal cord injury so better patient stratification and more sensitive outcomes are needed for proper evaluation of new interventions.

Assessment of Functional Improvement without Compensation Reduces Variability of Outcome Measures After Human Spinal Cord Injury

(Behrman AL, Ardolino E, VanHiel L, Kern M, Atkinson D, Lorenz DJ, Harkema SJ)

• The Neuromuscular Recovery Scale (NRS) is a new and unique measure of the degree a person who has sustained a spinal cord injury (SCI) has recovered the ability to perform functional tasks relative to how the individual performed these tasks prior to injury (i.e. the same movement pattern and without compensation such as assistive device or substitution by another muscle).
• NRS is more effective than other measures (of balance, walking or sensorimotor impairments) to classify SCI patients into functionally similar groups.
• The NRS may thus be a more sensitive instrument for assessing the therapeutic effect of an intervention tested in clinical trials and studies with the aim of achieving recovery after SCI.
• The NRS can provide the therapist and patient an effective means to quantify recovery, set goals, and assess progress.

Relationship Between AISA Examination and Functional Outcomes in the NeuroRecovery Network Locomotor Training Program

(Buehner J, Forrest G, Schmidt Read M, White S, Tansey K, Basso DM)

• Completing locomotor training in the NRN produced large improvements in walking speed for 70% of participants with incomplete spinal cord injury. Only 22% of participants remained non-ambulatory after completing the program. For many of the participants, the walking speed improved to levels thought to support community ambulation.
• Locomotor Training benefitted people with spinal cord injury by increasing muscle strength in the legs by almost 25% and strength in the arms by 8%. Surprisingly, the strength of the legs was not associated with the amount of locomotor recovery a person attained but it did relate to better balance.
• Improvement in walking speed with locomotor training may depend on several factors including the number of key muscles in the legs that are paralyzed and the number that have near normal strength when training begins. While most leg muscles tested show increased strength, the ankle muscles continue to be weaker than other muscles at the end of the training program.
• Surprisingly the AIS exam did not predict those individuals that would recover balance and walking function.

Longitudinal Patterns of Functional Recovery in Patients with Incomplete Spinal Cord Injury Receiving Activity-based Rehabilitation

(Lorenz DJ, Datta S, Harkema SJ)

• Individuals receiving NRN locomotor training recovered significant balance and walking function at a rate that plateaued over time.
• The Neuromuscular Recovery Scale (NRS), developed by NRN researchers, classifies patients into distinct groups of different functional ability and rates of recovery.
• Individuals with chronic incomplete SCI experienced recovery, but at a slower rate and magnitude than patients enrolled into the NRN sooner after their injuries.
• NRS classification, severity of injury, and time since spinal cord injury combined to create an accurate model for expected recovery with NRN locomotor training.

Ambulation and Balance Outcomes Measure Different Aspects of Recovery in Individuals with Chronic Incomplete Spinal Cord Injury

(Forrest GF, Lorenz DJ, Hutchinson K, VanHiel L, Basso DM, Datta S, Sisto SA, Harkema SJ)

• Scientists use outcome measures to document changes in patients' functional performance. These measurements help determine efficacy of interventions like locomotor training, guide decisions about which patients are likely to benefit, and support efforts to gain third-party reimbursement.
• This study of 182 outpatients with clinically incomplete spinal cord injury measured the impact of intensive standardized locomotor training on balance and walking ability using four clinical outcome measures (6-Minute Walk, 10-Meter Walk, Berg Balance Scale and Modified Functional Reach).
• Results show that these measures yield important information about different aspects of recovery of mobility, and that recovery of function during locomotor training can occur at different rates.
• Most importantly, these data underscore the importance of using more than one measure to evaluate the continuum of recovery after spinal cord injury. This is an important consideration for clinicians assessing the progress of their patients during locomotor training, as well as for researchers designing clinical trials for new rehabilitative interventions.

Dynamic Longitudinal Evaluation of the Utility of the Berg Balance Scale in Individuals with Motor Incomplete Spinal Cord Injury

(Datta S, Lorenz DJ, Harkema SJ)

• In the general incomplete SCI population, the Berg Balance Scale provides an adequate measure of balance that effectively distinguishes patients with poor, moderate, and strong balance function.
• The Berg Balance Scale performs poorly as a measure of balance in subgroups of patients with poor and strong balance function. New or adapted scales are needed to adequately measure balance in these subgroups.
• The ability of the Berg Balance Scale to measure balance function changes with time and as rehabilitation progresses. Patients with initially poor balance function regain the ability to perform tasks on the scale and it becomes a better measure of balance. Patients with initially strong balance function begin to score perfectly on all or nearly all tasks on the scale, further limiting its utility.

NeuroRecovery Network Provides Standardization of Locomotor Training for Persons with Incomplete Spinal Cord Injury

(Morrison SA, Forrest G, VanHiel L, Dave M, DeLorenzo D)

• This case study is of a 25-year old man with a motor incomplete spinal cord injury who received locomotor training for 100 sessions across two different NeuroRecovery Network centers.
• Walking endurance and walking speed showed consistent improvements during overground walking throughout the continuum of training.
• Within the treatment parameters of the body weight supported environment, consistent improvements were observed in average treadmill training speed, maximal training speed and amount of body weight support necessary.
• Overall, the results supported that the NRN standardized protocol provided a mechanism of delivering consistent and reproducible locomotor training across 2 geographically different sites.

Cardiovascular Status of Individuals with Incomplete Spinal Cord Injury from Seven NeuroRecovery Network Rehabilitation Centers

(Sisto SA, Lorenz DJ, Hutchinson K, Wenzel L, Harkema SJ, Krassioukov A)

• The purpose of this study was to examine cardiovascular health in a large cohort of individuals with incomplete spinal cord injury.
• Cardiovasular (CV) parameters, including blood pressure (BP) and heart rate (HR) were examined in 350 people with incomplete SCI at rest and after an orthostatic challenge involving an abrupt change from lying to sitting.
• The cardiovascular health parameters of patients were compared based on Spinal Injury Association Impairment Scores (AIS), neurological level, gender, central cord syndrome, age, time since injury, Neurological Recovery Scale, and total AIS motor score.
• Researchers concluded that resting cardiovascular parameters of blood pressure and heart rate are affected by position, age and neurological level. 21% of the patients had defined orthostatic hypotension (sudden fall in BP caused by standing or stretching)Results from this study provide reference for CV parameters for individuals with incomplete SCI.
• Clinical screening and treatments should be considered for cardiovascular dysfunction and orthostatic hypotension given the prevalence and persistence over months to years.

Locomotor Training: As a Treatment of Spinal Cord Injury and in the Progression of Neurological Rehabilitation

(Harkema SJ, Hillyer J, Schmidt Read M, Ardolino E, Sisto SA, Behrman AL)

• This article is a review of the current state of understanding of locomotor training and summarizes the findings of the NRN published in this focus issue.
• The evidence from these articles suggests that there is a paradigm shift in rehabilitation where recovery is expected and the therapy prioritizes recovery with compensation minimized to only what is necessary, with the intent of removing it as improvement in the neuromuscular systems continues.
• The most successful approach for evidence-based medicine may be to evaluate all levels of evidence based on their strengths and weaknesses.
• Rehabilitation, especially in the spinal cord injury population, seems to benefit from a comprehensive program, especially in the challenging financial environment we now face within the health care system.

Life Care Planning Projections for Individuals With Motor Incomplete Spinal Cord Injury Before and After Locomotor Training Intervention: A Case Series

(Morrison SA, Pomeranz J, Yu N, Schmidt Read M, Westcott C, Sisto SA, Behrman AL)

• This study presented case series of two individuals (four year old male and 61 year old female) with motor incomplete spinal cord injury to examine the differences in life cost estimates before and after participation in an intensive locomotor training program. A life care plan was used to project the lifetime costs before and after the intense locomotor training intervention.
• In both cases, the lifetime expenses associated with equipment, home renovations and transportation decreased.
• After 76 sessions, the four year old male had a decrease of expected lifetime expenses between $437,790 and $571,618 due to the gained function following the intense locomotor training intervention.
• After 198 sessions, the 61 year old female had a decrease of expected lifetime expenses between $148,237 and $197,208 due to the gained function following the intense locomotor training intervention.

Read the full article from the Journal of Neurological Physical Therapy.