Table I

Implants used at each stage of refinement for development of the rat model of direct fracture healing

Plate dimensions (mm)ScrewsOsteotomyCadavers (n)Animals (n)Observation
Initial arrangement16 × 4 × 11.6 mm diameter. Proximal screws in metaphysis0.5 mm thick saw10  2Proximal screw loosening
1st change16 × 4 × 11.4 mm diameter. All screws in diaphysis0.1 mm thick circular saw  5  2Fracture at distal screws on radiology at two weeks
2nd change12 × 3 × 1 1.2 mm diameter0.1 mm thick circular saw  5  4Wide gap on far cortex on histology at six weeks
3rd changePre-bent 12 × 3 × 0.81.2 mm diameter0.1mm thick circular saw  5  0Osteotomy displacement. Fracture on screw insertion
4th changePre-bent 12 × 3 × 0.61.2 mm diameter0.1 mm thick circular saw  5  0Osteotomy displacement. Fracture on screw insertion
Final arrangementPre-bent 12 × 3 × 0.41.2 mm diameter0.1 mm thick circular saw1510Better symmetric compression. Direct fracture healing