Table 10.
Summary Findings from This Review
| International Standards for Neurological Classification of Spinal Cord Injury (ISNCSCI) and American Spinal Injury Association Impairment Scale (AIS) |
| • Formal training before utilizing the ISNCSCI and AIS, and the use of a computational algorithm, is recommended to reduce classification errors. |
| • Examinations performed within 24 h are reliable in the absence of factors interfering with a patient's cognition and communication. Results from very early examinations (within 4 h of injury) should be interpreted with caution. |
| AIS conversion and change |
| • ∼30% of cervical level injuries initially classified (within 30 days of injury) as AIS A convert to incomplete status, with roughly one-half improving to AIS B and the other half to motor incomplete status. |
| • There is a probable trend of higher rates of neurological conversion in more recent literature compared with historical studies. |
| • Conversion from neurological complete to incomplete injury in tetraplegia is greater than with paraplegia. |
| • In complete paraplegia, the likelihood of conversion largely depends on the level of injury, with lumbar injuries having a greater prognosis relative to thoracic lesions, with high thoracic (T2–T6) injuries having the poorest prognosis. |
| • A sensory zone of partial preservation (ZPP) of ≥3 segments plays a prognostic role in AIS conversion for persons with an initial neurological level of injury (NLI) between T6–T12. |
| • Persons with AIS B (tetraplegia and paraplegia) have a greater likelihood of improving to motor incomplete status at one year than those with initial AIS A. |
| • The modality and extent of sacral sparing has prognostic value in neurological recovery over one year. In AIS B, initial sparing of all sacral sensory components is associated with improved conversion to motor incomplete status. In AIS C, initial voluntary anal contraction (VAC) in combination with other sacral examination components is associated with the greatest percentage of improvement to AIS D grade, with sacral sparing of VAC alone having the poorest prognosis for recovery to AIS D. |
| Motor recovery in one year |
| • The majority of motor recovery occurs within the first six to nine months, with the most rapid rate of recovery occurring in the first three months after injury. |
| • Spontaneous motor recovery typically plateaus around 12–18 months post-injury, with the rate and extent of recovery being greater for incomplete lesions. |
| • Motor change in persons with initial AIS A tetraplegia from initial assessment (usually <30 days) is ∼8–12 points. |
| • In AIS A tetraplegia, ∼65% of persons will regain at least 1 motor level (20–30% 2 or more levels); ∼5% will deteriorate 1–3 motor levels, and up to 30% will experience no change. |
| • The initial strength, as well as the amount of levels of the motor ZPP, play a prognostic role in the number of motor levels recovered after cervical complete tetraplegia. |
| • In neurological complete paraplegia, the change in motor level is usually small with the level of injury playing an important role; lumbar lesions having greater recovery followed by low thoracic, with high thoracic levels having the least chance of lower-exremity moor score (LEMS) improvement. |
| • Total motor recovery in the upper and lower extremities is greater for persons with initial AIS B than AIS A tetraplegia and greater after initial motor incomplete spinal cord injury (SCI) than with motor complete injuries. |
| • The reported mean change in total motor score in motor incomplete (AIS C) tetraplegia is between 22–52 points from baseline to 6–12 months post-injury, usually divided between upper-extremity motor score (UEMS) and LEMS. |
| • Changes in motor scores are lower for persons with initial AIS D tetraplegia because of a ceiling effect. |
| • For persons with initial motor incomplete paraplegia, mean changes in LEMS range from 9.0–34.3 from initial examination to follow-up assessment 6–12 months post-injury. |
| Sensory recovery in first year |
| • Mean changes in pinprick (PP) and light touch (LT) scores from baseline assessment in tetraplegia are highly variable. |
| • For persons with initial complete paraplegia, the mean sensory score improvement is between 1–5 points each for PP and LT. |
| • The sensory level (and corresponding NLI) does not change significantly after neurologically complete paraplegia between T2–L1, because most individuals (∼90%) remain within 1–2 levels of their initial level. This includes ∼1/3 of patients each losing ≥1 level, staying the same, and regaining ≥1 level. |
| • Individuals with initial sensory incomplete tetraplegia (AIS B) regain significantly more sensory function than a person with initial AIS A. |
| Other factors |
| • Older age seems to have a negative impact on neurological and functional recovery after SCI. The specific age (whether >50 or >65 years) and the true nature of this impact on neurological recovery, however, is unclear. |
| • Penetrating (violence related) injury is more likely to lead to a classification of a neurological complete injury compared with blunt trauma and may reduce the likelihood of AIS conversion. |
| • There are insufficient data to support gender having a major effect on neurological recovery after SCI. |