The Gertzbein classification was published in 1990 and is used to classify medial breaches of pedicle screws from T8 to S1[^1].
Grade | Breakthrough Distance (mm) |
Grade 0 | Screw in pedicle |
Grade 1 | < 2 mm |
Grade 2 | 2-4 mm |
Grade 3 | > 4 mm |
In the original study of the classification, pedicle screw breakthroughs of more than 4 mm were associated with neurological deficits[^1].