Characterizing Natural Recovery of People with Initial Motor Complete Tetraplegia

Abstract Objective To determine the differences in neurological recovery in persons with initial cervical ASIA Impairment Scale (AIS) grades A and B over time. Design Retrospective analysis of data from people with traumatic cervical SCI enrolled in the National Spinal Cord Injury Model Systems (SCIMS) database between 2011-2019. Setting SCIMS centers. Participants Individuals (N=187) with traumatic cervical (C1-C7 motor level) SCI admitted with initial AIS grade A and B injuries within 30 days of injury, age ≥16 years, upper extremity motor score (UEMS) ≤20 on both sides, and complete neurological data at admission and follow-up between 6 months and two years. Interventions Not applicable. Main Outcome Measures Conversion in AIS grades, UEMS and lower extremity motor scores (LEMS), and sensory scores. Results Mean time to initial and follow-up exams were 16.1 ±7.3 days and 377.5 ±93.4 days respectively. Conversion from an initial cervical AIS grades A and B to motor incomplete status was 13.4% and 50.0% respectively. The mean UEMS change for people with initial AIS grades A and B did not differ (7.8±6.5 and 8.8±6.1; p=0.307) but people with AIS grade B experienced significantly higher means of LEMS change (2.3 ±7.4 and 8.8±13.9 (p= Conclusions While UEMS recovery is similar in persons with initial AIS grades A and B, the rate of conversion to motor incomplete status, LEMS, and sensory recovery are significantly different. This information is important for clinical as well as research considerations.