Table 2 Screw placement quality with modified classification of Gertzbein and Robbins
From: Cortical screw placement with a spinous process clamp guide: a cadaver study accessing accuracy
Grade | Total (n = 96) | Planning screws (n = 48) | Inserted screws (n = 48) | P value |
|---|---|---|---|---|
A (n %) | 85 (88.5%) | 45 (93.8%) | 40 (83.3%) | 0.199 |
B (n %) | 8 (8.3%) | 3 (6.3%) | 5 (10.4%) | 0.714 |
C (n %) | 3 (6.3%) | 0 | 3 (6.3%) | 0.242 |
D (n %) | 0 | 0 | 0 | NA |
E (n %) | 0 | 0 | 0 | NA |
A + B (n %) | 93 (96.9%) | 48 (100%) | 45 (93.8%) | 0.242 |
C + D + E (n %) | 3 (6.3%) | 0 | 3 (6.3%) | 0.242 |
FJV (n %) | 4 (4.2%) | 1 (2.1%) | 3 (6.3%) | 0.617 |