The effects of blocking an uncemented universal nail on the hip on the subsidence of the implant and on the mechanical properties of the cadaveric canine femur.

• Autor(a) principal: Ferreira Lemos, Antonio Carlos
• Data de Publicação: 2019
• Outros Autores: Corrêa Silva, Antônio Fernando
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Brazilian Journal of Implantology and Health Sciences
• Texto Completo: https://bjihs.emnuvens.com.br/bjihs/article/view/46
• topic: Osseointegração; Implante; Estudo biomecânico; Fêmora canina; Osseointegration; Implant; Biomechanical study; Canine femoral

Objective: Determine whether a locking screw would limit the subsidence of the universal biological fixation hip femoral stem (BFX ®) under cyclic load and increase the rigidity, performance and failure properties of the construction. Material and method: Paired femurs implanted with a traditional rod or a locking rod (constructions) were loaded cyclically in walking, trotting and galloping loads, while the movements of the implant and bone were captured using kinematic markers and high-speed video. . Buildings were loaded to the fault to assess the mechanical properties of the fault. Results: The subsidence of the implant was greater (P = 0.037) for the traditional implant (4.19 mm) than the interlocked implant (0.78 mm) only after cyclical canter loading and cumulatively after cyclical walking, trotting and gallop (5.20 mm vs. 1.28 mm, P = 0.038). The yield and failure loads were higher (P = 0.029 and 0.002, respectively) for the interlocking rod construct (1155 N and 2337 N) than the traditional rod construct (816 N and 1405 N). The change in the version angle after cyclic loading was greater (P = 0.020) in the traditional implant (3.89 degrees) than in the interlocked implant (0.16 degrees), while the varus displacement of the nail in the failure was greater ( P = 0.008) for the blocking implant (1.5 degrees) than the traditional implant (0.17 degrees). Conclusion: The addition of a stabilizing screw improved the stability of the construction and limited subsidence of a BFX ® femoral stem. The use of the interlocked implant can decrease postoperative subsidence. However, the in vivo effects of the blocking screw on osseointegration, bone remodeling and protection against stress are unknown.