Evolution of tibial SSEP after traumatic spinal cord injury: baseline for clinical trials

To describe the spontaneous evolution of tibial somatosensory evoked potentials (tSSEPs) after spinal cord injury (SCI) and its relation to neurological and functional parameters.

tSSEPs were assessed in 297 patients within five standardized time intervals throughout the first year after injury, along with neurological and functional parameters.

Roughly 60% of the patients did not show any recordable tSSEP throughout the first year after injury. Approximately 20% had recordable potentials at every assessment stage and showed an improvement of tSSEP parameters over time. In about 10% of the patients, a potential recovered during the first year. In the remaining cases, potentials were inconsistently recordable. All groups showed a similar amount of neurological and functional improvement.

Recordability, latencies and amplitudes of tSSEPs can change over time after SCI. The early recordability of a tSSEP is associated with a favorable functional and neurological status and outcome. In contrast, an initially absent tSSEP is not always associated with a poorer status and outcome but only in those 75% of the patients in whom the potential remains absent.

This exact description of the spontaneous improvements of neurophysiological, neurological and functional parameters after SCI is an important prerequisite in appraising the efficacy of new interventional therapies.