Table 4.
IOM versus no-IOM, before surgery.
| IOM | No-IOM | ||
|---|---|---|---|
| Number of patients | 51 | 35 | |
| Age (years, mean ± SD) | 66.1 ± 14 | 65.8 ± 13.4 | p = 0.914 |
| Sex | p = 1.000 | ||
| Women | 44 | 31 | |
| Men | 7 | 4 | |
| Location | p = 0.147 | ||
| Dorsolateral | 28 | 13 | |
| Lateral | 15 | 10 | |
| Ventrolateral | 8 | 11 | |
| NA | 0 | 1 ** | |
| Level | p = 0.841 | ||
| Cervical | 8 | 7 | |
| Junction | 3 | 1 | |
| Thoracic | 40 | 27 | |
| Modified McCormick preoperative | p = 0.874 | ||
| I | 10 | 6 | |
| II | 22 | 16 | |
| III | 15 | 9 | |
| IV | 3 | 4 | |
| V | 1 | 0 | |
| Tumor-canal ratio *** (TCR) (%, mean ± SD) |
66.2 (±19.7) (n = 50) |
61.8 (±20.5) (n = 33) |
p = 0.328 |
| Deficit before surgery | p = 0.502 * | ||
| None | 10 | 9 | |
| Sensory | 12 | 8 | |
| Motor | 5 | 5 | |
| Both | 24 | 13 |
* The indicated p-value is the result of the corresponding chi-square or Fisher’s exact test of the 2 × 2 cross-table comparing IOM (yes/no) with deficits (none/any). ** This patient did not have an MRI. *** For some patients, the TCR could not be determined due to technical limitations (e.g., bad quality MRI).