Study Design & Setting: Prospective multi-center longitudinal cohort study within the ‘European Multicenter Study of Human Spinal Cord Injury’ (EM-SCI) consortium.

Introduction: Determination between complete and incomplete spinal cord injury (SCI) is commonly applied in prognosticating patients’ functional recovery. Complete and incomplete injury is defined by absence or presence of at least 1 of 4 ASIA sacral sparing (SS) criteria. To date, however, the ASIA SS criteria have not been validated with respect to chronic phase functional outcomes.

Objectives: To validate the prognostic value of the acute phase sacral sparing (SS) measurements regarding to chronic phase ambulation in traumatic SCI patients.

Methods: In 251 patients, acute phase (0–15 days) ASIA Impairment Scale (AIS) grades, ASIA SS measurements and chronic phase (6 or 12 months) Timed Up & Go (TUG) outcome measurements were analyzed. Calculation of sensitivity, specificity, positive and negative predictive values (PPV/NPV), univariate and multivariate logistic regressions were performed in all 4 SS criteria. The area under the receiver-operating characteristic curve (AUC) ratios of all regression equations were calculated.

Results: In completing the 1-year follow-up TUG test, presence of voluntary anal contraction (VAC) showed the best PPV (94.3%, p< 0.001, 95% CI: 80.8–99.3). Best NPV was reported in the S4–5 light touch (LT) score (96.9%, p< 0.001, 95% CI: 92.9–98.9). Presence of anal sensation in the traumatic SCI patients resulted in a PPV of 41% (p=0.124). Use of the combination VAC and S4–5 LT score (AUC: 0.917, p< 0.001, 95% CI: 0.868–0.966) showed significantly better (p< 0.001, 95% CI: 0.042–0.102) discriminating results in 1-year TUG test prognosis than with use of currently used distinction between complete and incomplete SCI (AUC: 0.845, p< 0.001, 95% CI: 0.790–0.901).

Conclusion: Out of the 4 sacral sparing criteria, VAC and S4–5 LT scores are the only acute phase measurements contributing significantly to the prognosis of ambulation. With the combination of acute phase VAC and S4–5 LT scores, significantly better chronic phase ambulation prognosis can be predicted than with use of currently used distinction between complete and incomplete SCI. This study stresses the importance of further research on functional predictive algorithms in the acute setting of traumatic SCI care.