Table 7.
Occurrence of damage to specific brain regions within cadaver heads from mature boars (BW < 200 kg) assigned to three penetrating captive bolt (PCB) placements1 and sectioned by band saw following the plane of bolt entry
| PCB placement | Brain structures | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Frontal lobe | Parietal lobe | Temporal lobe | Occipital lobe | Corpus callosum | Diencephalon | Mesencephalon | Brainstem (pons and medulla) | Cerebellum | ||
| FRONTAL | ||||||||||
| Proportion | 0/9 | 8/9 | — | 8/9 | 7/9 | 2/9 | 0/9 | 0/9 | 3/9 | |
| Percentage2 | 0.0 | 88.9 | — | 88.9 | 77.8 | 22.2 | 0.0 | 0.0 | 33.3 | |
| 95% CI3 | 0.0% to 33.6% | 51.8% to 99.7% | — | 51.8% to 99.7% | 40.0% to 97.2% | 2.8% to 60.0% | 0% to 33.6% | 0% to 33.6% | 7.5% to 70.0% | |
| TEMPORAL | ||||||||||
| Proportion | — | 7/10 | 1/1 | — | 1/1 | 0/1 | — | — | — | |
| Percentage2 | — | 70.0 | 100.0 | — | 100.0 | 0.0 | — | — | — | |
| 95% CI3 | — | 34.8% to 93.3% | 2.5% to 100.0% | — | 2.5% to 100.0% | 0% to 97.5% | — | — | — | |
| BEHIND EAR | ||||||||||
| Proportion | — | 0/11 | 4/11 | 4/11 | 0/11 | 0/11 | 0/11 | — | — | |
| Percentage2 | — | 0.0 | 36.4 | 36.4 | 0.0 | 0.0 | 0.0 | — | — | |
| 95% CI3 | — | 0.0% to 28.5% | 10.9% to 69.2% | 10.9% to 69.2% | 0.0% to 28.5% | 0.0% to 28.5% | 0.0% to 28.5% | — | — | |
1Placements: FRONTAL—Medial bolt entry approximately 3.5 cm superior to the optic orbits at midline perpendicular with the external surface of the head; TEMPORAL—Bolt entry at the depression located between the right eye and right ear; BEHIND EAR—Bolt entry directly caudal to the pinna of the ear on the same plane as the eyes and targeting the middle of the opposite eye.
2Statistical models to compare captive bolt placement effects would not converge due to the different regions of the brain which were accessible to the bolt path and exposed on the split head between PCB placements. As a result, 95% CIs were calculated and reported.
395% Confidence interval for the percentage of brain damage.