Impact of screw reinsertion on osteosynthesis stability in Schatzker IV tibial plateau fractures: a biomechanical study.

Abstract

Introduction: This biomechanical study evaluated the effect of screw reinsertion with a locking plate on fixation strength and the stability of osteosynthesis in medial tibial plateau fractures using porcine bone.

Materials and methods: Thirty porcine tibiae were divided into three groups: group A (underwent biomechanical testing after medial tibial fixation with a large fragment T-shaped locking plate), group B (underwent plate fixation, followed by the removal of all screws and plates and refixation with the same screws and plates using the same holes before biomechanical testing), and group C (underwent biomechanical testing once after plate fixation, followed by the removal of all screws and plates, refixation with the same screws and plates using the same holes, and then biomechanical testing). The translation pattern of the constructs in each group was examined using cyclic loading tests. The changes in the joint gap and step-off after 2000 cycles were compared among the three groups.

Results: Significant differences in displacement were observed at 10-100 cycles (group A: -0.01 ± 0.04 mm, group B: -0.02 ± 0.04 mm, group C: -0.13 ± 0.15 mm, P = 0.021). However, no significant differences were found in other displacement and translation measurements among the groups. Regarding the gap and step-off among groups, significant differences were observed in anterior and posterior gap changes. Despite the statistical significance, the absolute displacement values were small, suggesting minimal clinical relevance. These findings indicate that reinserting screws and plates into the same hole may not substantially compromise overall fixation strength.

Conclusion: Screw reinsertion in the same holes after removal did not significantly compromise the stability of osteosynthesis in this biomechanical model. These findings suggest that reinsertion may be a viable option in revision surgery.