Decompression for Traumatic Thoracic/Thoracolumbar Incomplete Spinal Cord Injury: Application of AO Spine Injury Classification System to Identify the Timing of Operation.

Objective: Application of AO spine injury classification system (AOSICS) to identify the timing of operation for different types of traumatic thoracic/thoracolumbar incomplete spinal cord injury (SCI).

Methods: A single-center prospective cohort study was conducted to enroll patients with thoracic/thoracolumbar incomplete SCI from April 2013 to November 2016; they were divided into an early group (<24 hours after SCI) and a late group (24-72 hours after SCI). Each group was divided into A, B, C subgroups according to AOSICS. The primary outcomes were ordinal changes in ASIA Impairment Scale at 12-month follow-up. The secondary outcomes included the Medical outcomes study 36-term short form health survey physical component summary (PCS), complications, mortality, and hospital length of stay (LOS).

Results: Seven hundred twenty-one patients with thoracic/thoracolumbar incomplete SCI were included; 335 patients underwent early surgery, and 386 patients underwent delayed surgery. Statistical results included the following comparisons of the early versus late groups: AIS improvement of 1 grade or more (combined groups: P = 0.009, odds ratio [OR] = 1.487; A: P = 0.777, OR = 1.072; B: P = 0.029, OR = 1.701; C: P = 0.007, OR = 1.762), AIS improvement 2 grades or more (combined groups: P = 0.002, OR = 2.471; A: P = 0.189, OR = 3.939; B: P = 0.011, OR = 2.550; C: P = 0.035, OR = 3.964) and PCS (combined groups: P = 0.327; A: P = 0.776; B: P = 0.019; C: P = 0.562). LOS (combined groups: P < 0.0001; A, B and C: P < 0.0001). Complications (combined groups: P = 0.267; A: P = 0.830; B: P = 0.111; C: P = 0.757).

Conclusions: Patients with type-A injuries with incomplete SCI do not have to undergo aggressive early operations. Patients with type-B and type-C injuries should undergo an operation early to achieve better clinical results.