| Perforated ulcer group | Control group |
---|---|---|
All patients | 13 (100) | 26 (100) |
Surgical site | ||
 Cervical spine | 1 (8) | 3 (12) |
 Thoracolumbar and lumbar spine | 12 (92) | 23 (88) |
Surgical levels | ||
  ≥ 3 | 7 (54) | 16 (62) |
  < 3 | 6 (46) | 10 (38) |
Surgical methods | ||
 Posterior instrumentation | 11 (84) | 20 (78) |
 Anterior surgery with instrumentation | 1 (8) | 3 (12) |
 Discectomy | 1 (8) | 3 (12) |