Influence of proximal cancellous bone void volume on the rigidity of tibial plateau fracture fixation: An observational study

BACKGROUNDDepressed tibial plateau (TP) fractures frequently result in metaphyseal cancellous bone voids following fracture reduction.The influence of cancellous bone void volume (CBVV) and location on the rigidity of fracture fixation constructs remains poorly understood despite potential implications for surgical decision-making. AIMTo assess the effect of CBVV on the rigidity of TP fracture fixation.METHODS TP fractures with different levels of CBVV (Scenario 1: 10% distal, Scenario 2: 50% distal, and Scenario 3: 50% proximal) were created in fourth-generation Sawbones models and fixed according to standard surgical practice.The samples were loaded under controlled conditions, and rigidity was assessed.Descriptive statistics were used to test for normality, and statistical significance was determined using one-way analysis of variance. RESULTSAll samples completed all loading sequences without failure.Loading to the capacity of the load frame (3 kN) did not result in fixation failure; therefore, no compressive load at failure was recorded.As expected, vertical displacement increased with increasing compressive load.The average fracture gap opening at the maximum applied load (2900 N) was 0.057 ± 0.056 mm, 0.066 ± 0.044 mm, and 0.124 ± 0.077 mm for scenarios 1-3, respectively.The average construct stiffness was 1469 ± 57 N/mm, 1484 ± 73 N/mm, and 1467 ± 23 N/mm for scenarios 1-3, respectively.No statistically significant differences were observed in vertical displacement, gap opening, or stiffness (P > 0.05).5 / 20 CONCLUSION No statistically significant differences in rigidity were found between constructs with varying CBVV.However, a trend was observed, with the 50% proximal deficit demonstrating the least rigidity.Further research is warranted to investigate if proximal cancellous bone voids may warrant adjunctive support during TP fracture fixation.