Revista de la Asociación Argentina de Ortopedia y Traumatología
versión On-line ISSN 1852-7434
LUGONES, Alfonso; CATA, Carlos E. y ALLENDE, Christian. Comparative esperimental biomechanical study of locked compression plate in diaphyseal fractures. Rev. Asoc. Argent. Ortop. Traumatol. [online]. 2009, vol.74, n.2, pp. 152-166. ISSN 1852-7434.
Background: To evaluate the biomechanics of locked compression plates in long bone diaphyseal fractures using different screws in different combinations and distributions. Methods: We used 65 cadaveric tibias of calves, divided in 13 groups of 5 bones each. We evaluated different constructs with 10-hole LCP. In 6 groups we worked on normal bone; in 3 we used only locking screws in different locations and quantity; in 2 groups only conventional compression screws were used, in different orientations, and in the last group we combined compression and locking techniques (hybrid). In another 6 groups we simulated osteoporotic bone. In one group we used screws with a big core and a small thread.We evaluated stability, rigidity and, progressive and continuous bending strength (DecaNewton) and measured the elasticity (mm) of each construction to failure. Results: In normal bone, the group with the greater elasticity was the construct with 3 locked screws (19.3 mm.). The group with the greater bending strength was LCP with compression screws in divergent orientations (788 kN.). In simulated osteoporotic bone, no difference was found between the groups. Conclusions: Divergent orientation of the screws increases significantly the construct strength. Skipping two or three holes on both sides of the fracture increases significantly the elasticity of the construct, when locked plates are used.
Palabras clave : Locked compression plates; Biomechanical; Diaphyseal fractures.