The overall objective of this fully powered clinical trial is to investigate if using a solid backrest on a manual wheelchair (MWC) will improve postural alignment, function and wheelchair mobility, as compared with an upholstery backrest, and to explore the impact of overall back height, contour, and seat gap when using a solid backrest in individuals with spinal cord injury (SCI).

A properly fit wheelchair and seating system can have a profound impact on the daily life of people with spinal cord injury (SCI). A backrest that supports the natural spinal curves is thought to enhance posture, functional mobility, and comfort for manual wheelchair (MWC) users. In fact, therapists routinely prescribe after-market posture-backs based on clinical reasoning. However, there is little research comparing the efficacy of an after-market posture-back to the standard upholstery back, and it is becoming increasingly difficult to justify these to group insurance payers.

Based on this, investigators performed a pilot study to investigate whether there were postural and/or functional differences between using a standard upholstery WC back and an after-market solid posture-back. The results of that study have been presented at the American Congress of Rehabilitation Medicine (ACRM) annual conference in November 2019 and the Combined Sections Meeting (CSM) of the American Physical Therapy Association (APTA) in February 2020, and were also published in the Journal of Spinal Cord Medicine in 2020.

Although the results of that study demonstrated clinical relevance and statistical trends for improvements in postural alignment and functional outcomes when using a solid back, there was not enough power to establish statistical significance. It also did not evaluate the effect of backrest height and position or depth of contour in order to inform clinical practice. The overall objective of this fully powered clinical trial is to further investigate if using a solid backrest on MWC will improve postural alignment, function and wheelchair mobility, as compared with an upholstery backrest; and to explore the impact of overall back height, seat gap, and contour when using a solid backrest.

Inclusion Criteria:

• Full time manual wheelchair users
• Motor complete SCI from C6-T4
• Age 18-70 at time of testing
• Time since injury > 3 month at time of testing

Exclusion Criteria:

• Weight >250 pounds
• Current pressure ulcer at time of testing
• Significant shoulder pain that precludes independent mobility at time of testing
• Insufficient range of motion to achieve neutral pelvis and spine at time of testing
• Orthopedic restrictions requiring a brace that would impact functional outcome measures
• Shoulder flexion range of motion <120 degrees at time of testing
• PSIS-to-Inferior Angle of scapula measurement less than 8 inches or greater than 16 inches
• Cognitive deficits or visual impairment that would impair ability to give informed consent or to follow simple instructions during testing
• Children, pregnant women and prisoners will not participate in this study