Do working length and proximal screw density influence the velocity of callus formation in distal tibia fractures treated with a medial bridge plate?

Introduction: Aim of our study was to evaluate the influence of working length and screw density on callus formation in distal tibial fractures fixed with a medial bridge plate. Materials and methods: 42 distal tibia fractures treated with a bridge plate were analyzed. Minimum follow-up was 12 months. mRUST score (modified Radiographic Union Scale for Tibial fractures) was used to assess callus formation. Working length and screw density were  measured from post-operative radiographs. Results: 39 (92.9%) fractures healed uneventfully. 32 (76.19%) patients showed signs of early callus formation 3 months post-surgery. In these patients a lower screw density was used compared to patients who didn't show early callus (33.4 vs. 26.6; p = 0.04). No differences was noticed in working length. Conclusion: Bridge plate osteosynthesis is a good treatment option in distal tibia fractures. In our series increasing the working length was not associated with a faster callus formation in distal tibia fractures. Conversely, a lower screw density proximally to the fracture site was associated to a faster callus growth.