Mono- versus polyaxial locking plates in distal femur fractures – a biomechanical comparison of the Non-Contact-Bridging- (NCB) and the PERILOC-plate

BMC Musculoskeletal Disorders

Research Article

Ralph Zettl¹  Turgay Efe²  Bilal Farouk El-Zayat²  Salim Khatib³  Antonio Krüger³  Steffen Ruchholtz³  Nina Timmesfeld⁴ 

[1] Department of Orthopaedic Surgery, Kantonsspital Frauenfeld, Pfaffenholzstrasse 4, 8501, Frauenfeld, Switzerland;Department of Orthopaedics and Rheumatology, University Hospital Marburg, 35043, BaldingerstrasseMarburg, Germany;Department of Trauma, Hand and Reconstructive Surgery, University Hospital Marburg, 35043, BaldingerstrasseMarburg, Germany;Institute for Medical Biometry and Epidemiology, Philipps University Marburg, Bunsenstraße 3, 35037, Marburg, Germany;

关键词: Monoaxial and polyaxial locking plates;    Biomechanical study;    Distal femur fracture;    NCB;    PERILOC;   

DOI  :  10.1186/1471-2474-15-369

 received in 2014-05-07, accepted in 2014-10-27,  发布年份 2014

来源: Springer

【 摘 要 】

BackgroundThe aim of this cadaveric study was to compare a polyaxial (NCB®, Zimmer) to a fixed-angle monoaxial locking plate (PERILOC®, Smith & Nephew) in comminuted fractures of the distal femur regarding stability of the construct. Up to date there is no published biomechanical data concerning polyaxial plating in cadaveric distal femurs.MethodsFourteen formalin fixed femora were scanned by dual-energy x-ray absorptiometry. As fracture model an unstable supracondylar comminuted fracture was simulated. Fractures were pairwise randomly fixed either with a mono- (group A) or a polyaxial (group B) distal femur plate. The samples were tested in a servohydraulic mechanical testing system starting with an axial loading of 200 N following an increase of 200 N in every step with 500 cycles in every sequence up to a maximum of 2 000 N. The end points were implant failure or relevant loss of reduction. Data records included for each specimen time, number of cycles, axial load and axial displacement. Statistical analysis was performed using the exact Wilcoxon signed rank test.ResultsThe mean donor age at the time of death was 75 years. The bone mass density (BMD) of the femurs in both groups was comparable and showed no statistically significant differences. Five bones failed before reaching the maximum applied force of 2000 N. Distribution curves of all samples in both groups, showing the plastic deformation in relation to the axial force, showed no statistically significant differences.ConclusionsOperative stabilization of distal femur fractures can be successfully and equally well achieved using either a monoaxial or a polyaxial locking plate. Polyaxial screw fixation may have advantages if intramedullary implants are present.

【 授权许可】

CC BY   
© El-Zayat et al.; licensee BioMed Central Ltd. 2014