A novel anatomical integrated acetabular plate for acetabular fracture involving posterior wall /column: a biomechanical study

Xuan Pei^1,2Yu Chen²Zhixun Fang³Ziren Xiong²Jianan Chen⁴Yifan Zheng⁵Ting Wang⁶Shenglong Qian²Long Chen⁷Guodong Wang²Jing Qi²Ximing Liu^2*

• ¹Technical University Dresden, Dresden, Germany
• ²People's Liberation Army General Hospital of Central Theater Command, Wuhan, China
• ³The Third Hospital of Xiamen, Xiamen, China
• ⁴Tongji Medical College Medical Information Research Institute, Wuhan, China
• ⁵Southern Medical University Nanfang Hospital, Guangzhou, China
• ⁶Wuhan University of Science and Technology, Wuhan, China
• ⁷Universitat Rostock, Rostock, Germany

Introduction:The optimal treatment for complex acetabular fracture involving the posterior wall and column remains controversial. To address this issue, a novel anatomically integrated acetabular plate (AIP) was developed, designed to integrate the biomechanical advantages of both reconstruction and T-shaped plates. This biomechanical study aimed to evaluate the mechanical performance of the AIP in comparison with conventional fixation methods. Results: Under increasing axial loading, all three groups of model specimens exhibited a linear trend in axial displacement without sudden load drops. Among the groups, the AIP group demonstrated the smallest overall displacement (1.87 ± 1.09 mm), followed by the RPTP (2.29 ± 1.12 mm) and RPLS groups (2.63 ± 1.21 mm). No significant difference in displacement was observed between the AIP and RPTP groups under loads of 0-1000 N (P > 0.05), whereas a significant difference emerged at higher loads of 1200-1400 N (P < 0.05). Under a peak load of 1400 N, the axial stiffness followed the trend: Normal (NOR) group > AIP group > RPTP group > RPLS group, with mean stiffness values of 356.10 ± 12.33 N/mm, 339.87 ± 21.86 N/mm, 302.04 ± 13.69 N/mm, and 266.32 ± 9.16 N/mm, respectively. The AIP group exhibited significantly higher stiffness than both the RPTP and RPLS groups (P < 0.05), with no significant difference between the AIP and NOR groups (P > 0.05). Furthermore, the AIP group showed significantly lower displacement of the acetabular posterior wall and column compared to the RPTP and RPLS groups (P < 0.05). Notably, two specimens in the RPLS group showed posterior wall displacements exceeding 2 mm, which met the criteria for internal fixation failure. Conclusions: Overall, the AIP group provided the best biomechanical performance in 3 terms of minimizing displacement and maximizing stiffness, followed by RPTP and RPLS group, indicating its potential superiority for the stabilization of acetabular fractures involving the posterior wall and column.