Table 3. Intraoperative variables and complications.
| Variables | Anterior (n=96) | Posterior (n=225) | Combined (n=122) | P value |
|---|---|---|---|---|
| Median # of levels [IQR] | 4 [4–5] | 5 [4–6] | 5 [4–6] | 0.94 |
| X-ray (%) | 45.8 | 40.7 | 40.2 | 0.64 |
| SSEP (%) | 10.4 | 8.9 | 2.5 | 0.04* |
| TcMEP (%) | 8.3 | 8.9 | 2.5 | 0.07 |
| EMG (%) | 11.5 | 15.0 | 21.3 | 0.12 |
| Fluoroscopy (%) | 68.8 | 49.1 | 89.3 | <0.0001* |
| Operative time (min) | 242.8±147.1 | 262.2±117.0 | 349.3±141.8 | <0.0001* |
| EBL (mL) | 377.5±758.3 | 1,055.8±1,165.8 | 618.7±837.8 | <0.0001* |
| # of PRBC transfusions (1 unit =350 mL) | 0.27±0.75 | 0.83±1.5 | 0.64±1.3 | 0.002* |
| Spinal cord injury (%) | 0.0 | 0.0 | 0.0 | 1.00 |
| Nerve root injury (%) | 0.0 | 0.0 | 0.0 | 1.00 |
| Durotomy (%) | 0.0 | 11.1 | 4.1 | <0.001* |
IQR, interquartile range; SSEP, Sensory Stimulus Evoked Potentials; TcMEP, Transcranial Motor Evoked Potentials; EBL, estimated blood loss; PRBC, packed red blood cells. *, statistically significant.