CC BY-NC-ND 4.0 · Rev Bras Ortop (Sao Paulo) 2019; 54(04): 416-421
DOI: 10.1055/s-0039-1693046
Artigo Original | Original Article
Sociedade Brasileira de Ortopedia e Traumatologia. Published by Thieme Revnter Publicações Ltda Rio de Janeiro, Brazil

Biomechanical Test after Hip Cannulated Screw Removal (in vitro Analysis)[*]

Article in several languages: português | English
1  Instituto de Pesquisa e Ensino do Hospital Ortopédico e Medicina Especializada (IPE-HOME-DF), Brasília, DF, Brasil
,
Lucas S. Ramos
2  Serviço de Ortopedia e Traumatologia, Hospital Regional do Gama (HRG-DF), Brasília, DF, Brasil
,
Érgon LAB Dantas
2  Serviço de Ortopedia e Traumatologia, Hospital Regional do Gama (HRG-DF), Brasília, DF, Brasil
,
Vincenzo Giordano Neto
3  Serviço de Ortopedia e Traumatologia, Hospital Municipal Miguel Couto (HMMC-RJ), Rio de Janeiro, RJ, Brasil
,
Patrick F. Godinho
1  Instituto de Pesquisa e Ensino do Hospital Ortopédico e Medicina Especializada (IPE-HOME-DF), Brasília, DF, Brasil
,
Antônio C. Shimano
4  Departamento de Biomecânica, Medicina e Reabilitação do Aparelho Locomotor, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo (USP-RP), Riberião Preto, SP, Brasil
› Author Affiliations
Further Information

Publication History

01 March 2018

03 September 2018

Publication Date:
20 August 2019 (online)

Abstract

Objective This study aims to evaluate, through biomechanical tests, the resistance and energy required for proximal femoral fracture in synthetic bones after removing cannulated screws shaped as an inverted triangle, comparing the obtained results to those of a reinforcement technique with polymethylmethacrylate (PMMA) as bone cement.

Methods Twenty synthetic bones were used: 10 units for the control group (CG), 5 units for the test group without reinforcement (TGW/O), and 5 units for the test group using a reinforcement technique with PMMA (TGW). The biomechanical analysis simulated a fall on the large trochanter using a servo-hydraulic machine.

Results All TGW/O and CG specimens had a basicervical fracture. Three TGW specimens presented a basicervical fracture, and two suffered a fracture near the fixation point of the device (femoral diaphyseal region), with one of them being associated with a femoral neck fracture. A mean PMMA volume of 8.2 mL was used to fill the 3 screw holes in the TGW group. According to the one-way analysis of variance (ANOVA) and the Tukey multiple comparisons tests at a 5% level, the TGW presented a statistically significant difference when compared with the other groups in all parameters: maximal load (p = 0.001) and energy until fracture (p = 0.0001).

Conclusion The simple removal of the cannulated screws did not reduce significantly the maximum load and energy for fracture occurrence, but the proximal femoral reinforcement with PMMA significantly increased these parameters, modifying the fracture pattern.

* Work performed at the Orthopedics and Traumatology Service, Hospital Regional do Gama, Brasília, DF and Instituto de Pesquisa e Ensino do Hospital Ortopédico e Medicina Especializada (IPE-HOME), Brasília, DF, Brazil.