Predictors of Acute and Late Spasticity After Traumatic Spinal Cord Injury: Implications for Recovery.

BACKGROUND: Spasticity is a common complication following traumatic spinal cord injury (TSCI) that impacts neurofunctional recovery. OBJECTIVES: This study aimed to determine the prevalence of acute and late spasticity and identify clinical predictors associated with spasticity onset within the first year after TSCI. METHODS: We conducted a retrospective longitudinal cohort study involving 156 adults hospitalized for acute supraconal (C1-T12) TSCI at a level 1 trauma center from April 1, 2010, to December 31, 2021. Independent factors included demographic variables (age, sex, body mass index), trauma-related characteristics, and acute medical complications. Spasticity onset was categorized as acute (during acute hospitalization), late (after acute hospitalization within 1 year), or none. Multinomial logistic regression model was used to identify factors associated with the period of spasticity onset. RESULTS: Among the patients, 57 (36.5%) developed acute spasticity (mean onset at 24.7 ± 13.7 days after admission), 55 (35.3%) experienced late spasticity, and 44 (28.2%) showed no spasticity within the first year. Higher AIS motor score at admission was associated with greater likelihood of either late or no spasticity (OR 1.05, P < .001; OR 1.02, P = .04). High-energy trauma increased the risk of developing acute spasticity (OR 0.37, P = .04). An AIS motor score below 50 (most severely impaired) at admission identified individuals at higher risk of acute spasticity, with 85.7% sensitivity and 71% overall accuracy. CONCLUSION: Greater injury severity and high-energy trauma are associated with early spasticity onset, highlighting the need for early risk stratification and personalized management strategies to optimize patient outcomes.