Late neurologic recovery after traumatic spinal cord injury

OBJECTIVE: To present Model Spinal Cord Injury System (MSCIS) data on late neurologic recovery after 1 year after spinal cord injury (SCI). DESIGN: Longitudinal study of neurologic status as determined by annual evaluations at 1 and 5 years postinjury. SETTING: MSCIS centers contributing data on people with traumatic SCI to the National Spinal Cord Injury Statistical Center database. PARTICIPANTS: People with traumatic SCI (N=987) admitted to an MSCIS between 1988 and 1997 with 1- and 5-year follow-up examinations. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: American Spinal Injury Association (ASIA) Impairment Scale (AIS) classification, motor index scores (MIS), motor level, and neurologic level of injury (NLI), measured and compared for changes over time. RESULTS: The majority of subjects (94.4%) who had a neurologically complete injury at 1 year remained complete at 5 years postinjury, with 3.5% improving to AIS grade B, and up to 1.05% each improving to AIS grades C and D. There was a statistically significant change noted for MIS. There were no significant changes for the motor level and NLI over 4 years; however, approximately 20% of subjects improved their motor level and NLI. People with complete and incomplete injuries had similar improvements in motor level, but subjects with an incomplete injury had a greater chance of improvement in NLI and MIS. CONCLUSIONS: There was a small degree of neurologic recovery (between 1 and 5 y postinjury) after a traumatic SCI. Late conversion, between 1 and 5 years, from a neurologically complete to an incomplete injury occurred in 5.6% of cases, but in only up to 2.1% was there a conversion from motor complete to motor incomplete status. Limitations of this study included changes in the ASIA classification during the study and in the intra- and interrater reliability typically seen in longitudinal studies of the ASIA standards. Functional changes were not studied. Knowledge of the degree of late recovery may help in analyzing newer interventions to enhance recovery.