Why it is done point by point rather than by scraping: the porcine rib study
The technique aims for a monocortical fracture and to avoid the bicortical one, which is its characteristic complication. This work goes to the root of it: it measures, across 50 porcine ribs, how much force is needed depending on how the bone is approached. Perpendicular corticotomy — point to point, «dots point» — required less than half the force of parallel scraping.
What was compared, and how
Fifty ribs from 24-kg Yorkshire pigs, randomly assigned to one of two corticotomy orientations:
- Perpendicular (point to point, dots point)
- Parallel scraping (no dots point)
Each rib's dimensions were recorded with standardised instruments, and a calibrated digital dynamometer measured the force and time required to produce monocortical and bicortical fractures.
The result, in newtons
| Orientation | Force for monocortical fracture |
|---|---|
| Perpendicular (dots point) | 6.67 ± 1.07 N |
| Parallel scraping | 14.54 ± 1.27 N |
Rib weight and size were comparable between groups, so the difference is attributable to technique rather than to the bone.
The authors conclude that, in this model, perpendicular corticotomy showed biomechanical advantages: less force and better control in achieving safe monocortical fractures.
Why less force means more safety
If you need to press twice as hard for the same effect, you control less well where the fracture goes and how far. Going past the outer layer is precisely bicorticality, the complication the technique tries to avoid.
This is an ex vivo study, on porcine ribs. That is both a strength and a limit: it allows dynamometer measurement that would be impossible in theatre, but it does not replace clinical observation in patients. It explains why the technique is designed this way; it does not estimate complication rates.