Finite element analysis of double‐plate fixation using reversed locking compression‐distal femoral plates for Vancouver B1 periprosthetic femoral fractures

• Main Authors: Daisuke Takahashi, Yoshihiro Noyama, Tsuyoshi Asano, Tomohiro Shimizu, Tohru Irie, Mohamad Alaa Terkawi, Norimasa Iwasaki
• Format: Article
• Language: English
• Published: BMC 2021-03-01
• Series: BMC Musculoskeletal Disorders
• Subjects: Periprosthetic femoral fracture; Double plate; Vancouver B1; Finite element analysis; Locking compression‐distal femoral plate
• Online Access: https://doi.org/10.1186/s12891-021-04152-5

Abstract Background Internal fixation is recommended for treating Vancouver B1 periprosthetic femoral fractures. Although several fixation procedures have been developed with high fixation stability and union rates, long-term weight-bearing constructs are still lacking. Therefore, the aim of the present study was to evaluate the stability of a double-plate procedure using reversed contralateral locking compression-distal femoral plates for fixation of Vancouver B1 periprosthetic femoral fractures under full weight-bearing. Methods Single- and double-plate fixation procedures for locking compression-distal femoral plates were analysed under an axial load of 1,500 N by finite element analysis and biomechanical loading tests. A vertical loading test was performed to the prosthetic head, and the displacements and strains were calculated based on load-displacement and load-strain curves generated by the static compression tests. Results The finite element analysis revealed that double-plate fixation significantly reduced stress concentration at the lateral plate place on the fracture site. Under full weight-bearing, the maximum von Mises stress in the lateral plate was 268 MPa. On the other hand, the maximum stress in the single-plating method occurred at the defect level of the femur with a maximum stress value of 1,303 MPa. The principal strains of single- and double-plate fixation were 0.63 % and 0.058 %, respectively. Consistently, in the axial loading test, the strain values at a 1,500 N loading of the single- and double-plate fixation methods were 1,274.60 ± 11.53 and 317.33 ± 8.03 (× 10− 6), respectively. Conclusions The present study suggests that dual-plate fixation with reversed locking compression-distal femoral plates may be an excellent treatment procedure for patients with Vancouver B1 fractures, allowing for full weight-bearing in the early postoperative period.