The revised zone of partial preservation (ZPP) in the 2019 International Standards for Neurological Classification of Spinal Cord Injury: ZPP applicability in incomplete injuries

The International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) is used to assess the severity of a spinal cord injury (SCI). The zone of partial preservation (ZPP) indicates areas with some remaining function below the injury level. The 2019 revision broadened the applicability of ZPPs to include certain incomplete injuries, where previously it was mainly used for complete injuries. This revision allows for a more detailed assessment of residual functions in individuals with SCI. The revised ZPP helps clinicians and researchers better characterize neurological impairments, supports communication among clinicians, and may help identify different recovery patterns in individuals with SCI.

• 1
  Motor ZPPs were found in 35.2% of datasets from incomplete injuries, whereas sensory ZPPs were much less frequent (1.0%).
• 2
  Motor ZPPs are applicable in all American Spinal Injury Association Impairment Scale (AIS) B datasets, with a mean ZPP length of 0.9 ± 1.0 segments.
• 3
  Motor ZPPs are applicable in 55.4% of all AIS C datasets (ZPP length: 11.8 ± 8.2 segments) and in 9.9% of the AIS D datasets (ZPP length: 15.4 ± 7.9 segments).