Critical Time Window for Rehabilitation After Incomplete Spinal Cord Injury: Early vs Late Locomotor Training
Abstract
Background/Rationale: Most patients who sustain a spinal cord injury (SCI) lose the ability to walk and many never recover this ability even after prolonged rehabilitation. This loss of mobility imposes severe constraints on quality of life and the ability to return to community living. The average age of SCI onset is 27 years for military Service Members; thus, individuals with SCI have strong incentives to resume active community participation and employment – each depending in large part on restoration of locomotor function. While there are many innovative therapies under development, we rely heavily on retraining of motor function via massed practice to promote recovery. We know that intensive motor training promotes recovery by helping the nervous system to restructure neural circuits and to reprogram their functions. It is thought that the neural trauma associated with SCI initiates many of these corrective functions and that high-intensity training helps to remodel this plasticity. What remains unknown is the optimal time window during which the injured spinal circuitry is most responsive to training. It is our hypothesis that the most effective time to initiate such training (i.e., the time-sensitive window of plasticity) arises within the first few weeks after injury. This hypothesis is derived from retrospective studies and from our pilot data, which suggest that increased time from injury to initiation of rehabilitation is associated with poorer walking performance. Studies in animal models of SCI and parallel work in other neurological deficits, such as stroke, also support the notion that the capacity of the injured nervous system to respond to various training protocols may change radically according to time elapsed since injury. Accordingly, the overall objective of our study is to determine if there is a critical period of plasticity post-SCI in which training maximally improves function. To do this, we plan to compare the effects of high-intensity treadmill training, an intervention designed to restore locomotor function, administered in addition to routine care during the acute in-patient rehabilitation phase, and compare that with delayed high-intensity training provided at 3 or 6 months after the initial spinal trauma. Our specific aims are the following. Aim 1: To determine the critical time window for plasticity post-SCI by evaluating the effectiveness of 20 hours of additional high-intensity locomotor training provided in the early, subacute, or chronic stage following SCI. Aim 2: To determine the relationship between functional improvement achieved over the course of training and post-intervention walking activity, including community ambulation, using wearable sensors for up to 1 year post-SCI. Study Design: We will employ a randomized, multi-site, placebo-controlled, and repeated measures clinical trial study design. We will enroll 108 individuals with acute traumatic SCI at cervical or thoracic level (C5–T12) upon their admission to inpatient rehabilitation at our two clinical study sites: Shirley Ryan AbilityLab, Chicago, and Baylor Scott White Institute for Rehabilitation, Dallas, Texas. In Aim 1, we will deliver 20 additional hours of high-intensity body weight supported treadmill training (target 65%-80% maximum heart rate), in addition to their standard rehabilitation. This will be administered over a period of 4-6 weeks and will be initiated at an early (<45 days post-SCI), subacute (3 months post-SCI), or chronic (6 months post-SCI) time-point. We will also utilize a control group that will receive standard rehabilitation care as a basis for comparison. In Aim 2, we will monitor daily activity in these participants for 1 year post-injury using the Fitbit Inspire 2 wearable sensor to evaluate long-term improvements to walking and community ambulation. Participants will complete multiple performance- and patient-reported measures upon enrollment, pre-training, p
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jan 04, 2024
- Source ID
- HT94252310418
Entities
People
- Milapjit Sandhu
Organizations
- Shirley Ryan AbilityLab
- United States Army