Predicting Duration of Outpatient Physical Therapy Episodes for Individuals with Spinal Cord Injury Based on Locomotor Training Strategy

Published:October 11, 2021DOI:



      To characterize individuals with spinal cord injuries (SCI) who use outpatient physical therapy or community wellness services for locomotor training and predict the duration of services, controlling for demographic, injury, quality of life, and service and financial characteristics. We explore how the duration of services is related to locomotor strategy.


      Observational study of participants at 4 SCI Model Systems centers with survival. Weibull regression model to predict the duration of services.


      Rehabilitation and community wellness facilities at 4 SCI Model Systems centers.


      Eligibility criteria were SCI or dysfunction resulting in motor impairment and the use of physical therapy or community wellness programs for locomotor/gait training. We excluded those who did not complete training or who experienced a disruption in training greater than 45 days. Our sample included 62 participants in conventional therapy and 37 participants in robotic exoskeleton training.


      Outpatient physical therapy or community wellness services for locomotor/gait training.

      Main Outcome Measures

      SCI characteristics (level and completeness of injury) and the duration of services from medical records. Self-reported perceptions of SCI consequences using the SCI-Functional Index for basic mobility and SCI-Quality of Life measurement system for bowel difficulties, bladder difficulties, and pain interference.


      After controlling for predictors, the duration of services for the conventional therapy group was an average of 63% longer than for the robotic exoskeleton group, however each visit was 50% shorter in total time. Men had an 11% longer duration of services than women had. Participants with complete injuries had a duration of services that was approximately 1.72 times longer than participants with incomplete injuries. Perceived improvement was larger in the conventional group.


      Locomotor/gait training strategies are distinctive for individuals with SCI using a robotic exoskeleton in a community wellness facility as episodes are shorter but individual sessions are longer. Participants’ preferences and the ability to pay for ongoing services may be critical factors associated with the duration of outpatient services.


      List of abbreviations:

      AIS (American Spinal Injury Association Impairment Scale), CI (credible interval), OR (odds ratio), PT (physical therapy), SCI (spinal cord injury), SCI-FI (Spinal Cord Injury-Functional Index), SCI-QOL (Spinal Cord Injury-Quality of Life)
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