Paiva Leonardo Morais, Macedo Neto Sílvio Leite de, Souto Diogo Ranier de Macedo, Ferreira George Neri Barros, Costa Hélio Ismael da, Freitas Anderson
Hospital Ortopédico e Medicina Especializada (HOME), Serviço de Quadril, Brasília, DF, Brazil.
Rev Bras Ortop. 2017 Aug 30;52(Suppl 1):52-56. doi: 10.1016/j.rboe.2017.01.008. eCollection 2017.
To evaluate, through biomechanical testing, the resistance to and energy required for the occurrence of proximal femoral fracture in synthetic bone after removal of a proximal femoral nail model (PFN), comparing the results obtained with a reinforcement technique using polymethylmethacrylate (PMMA).
Fifteen synthetic bones were used: five units for the control group (CG), five for the test group without reinforcement (TGNR), and five for the test group with reinforcement (TGR). The biomechanical analysis was performed simulating a fall on the trochanter using a servo-hydraulic machine. In the GC, the assay was performed with the PFN intact. In the TGNR and TGR groups, a model of PFN was introduced and the tests were performed in the TGNR, after simple removal of the synthesis material, and in the TGR, after removal of the same PFN model and filling of the cavity in the femoral neck with PMMA.
All groups presented a basicervical fracture. The CG presented a mean of 1427.39 Newtons (N) of maximum load and 10.14 Joules (J) of energy for the occurrence of the fracture. The TGNR and TGR presented 892.14 N and 1477.80 N of maximum load, and 6.71 J and 11.99 J of energy, respectively. According to the Kruskal-Wallis ANOVA, there was a significant difference in the maximum load ( = 0.009) and energy ( = 0.007) between these groups.
The simple removal of a PFN in synthetic bone showed a significant reduction of the maximum load and energy for the occurrence of fracture, which were re-established with a reinforcement technique using PMMA.
通过生物力学测试，评估在移除股骨近端钉模型（PFN）后，合成骨中股骨近端骨折发生的抵抗力和所需能量，并将所得结果与使用聚甲基丙烯酸甲酯（PMMA）的强化技术进行比较。
使用15个合成骨：5个作为对照组（CG），5个作为未强化测试组（TGNR），5个作为强化测试组（TGR）。使用伺服液压机模拟转子处跌倒进行生物力学分析。在CG组中，PFN完整时进行测定。在TGNR组和TGR组中，引入PFN模型，TGNR组在简单移除合成材料后进行测试，TGR组在移除相同的PFN模型并用PMMA填充股骨颈腔后进行测试。
所有组均出现股骨颈基底骨折。CG组骨折发生时的最大负荷平均为1427.39牛顿（N），能量为10.14焦耳（J）。TGNR组和TGR组的最大负荷分别为892.14 N和1477.80 N，能量分别为6.71 J和11.99 J。根据Kruskal-Wallis方差分析，这些组之间的最大负荷（P = 0.009）和能量（P = 0.007）存在显著差异。
在合成骨中简单移除PFN显示骨折发生时的最大负荷和能量显著降低，而使用PMMA的强化技术可使其恢复。
