Influence of Age Alone, and Age Combined With Pinprick, on Recovery of Walking Function in Motor Complete, Sensory Incomplete Spinal Cord Injury

Abstract

ObjectiveTo determine if age, pinprick scores in the lower extremities, and neurologic severity of injury influence recovery of ambulation in persons with motor complete, sensory incomplete (American Spinal Injury Association Impairment Scale [AIS] grade B) spinal cord injury (SCI) 1 year after initial injury. DesignThis retrospective analysis examined subjects with AIS grade B from the Spinal Cord Injury Model System (SCIMS) database from 2006 to 2015. The baseline neurologic examination at rehabilitation admission (2–4wk postinjury) was used for comparison with 1-year outcome measures of locomotion. SettingFifteen acute inpatient rehabilitation centers (participants in the SCIMS database). ParticipantsParticipants with AIS grade B SCI (N=249) were enrolled in the SCIMS database in 2 cycles (2006–2010 and 2011–2015). InterventionsNot applicable. Main Outcome MeasuresHousehold ambulation at 1 year by FONE-FIM and by direct interview, as part of the annual neurologic exam; change in American Spinal Injury Association score 1 year postinjury. ResultsFindings demonstrate a statistically nonsignificant increase in likelihood of walking for those age <50 years compared with those age ≥50 years (relative risk [RR]=1.99; 95% confidence interval, 0.80–3.04). Presence of pinprick in at least one half of the lower-extremity dermatomes L2-S1 was associated with higher likelihood of walking (RR=5.57, P=.0023). Pinprick was significant for patients age <50 years (RR=4.58, P=.0090) but not for those age ≥50 years (P=.15). ConclusionsCompared with younger individuals, participants age ≥50 years with AIS grade B SCI are less likely to achieve walking function 1 year postinjury. Likewise, preservation of pinprick sensation postinjury in the majority of lower-extremity dermatomes L2-S1 increases the chances of walking in individuals age <50 years.