title: BIOMECHANICAL STUDY OF TRANSCORTICAL OR TRANSTRABECULAR BONE FIXATION OF PATELLAR TENDON GRAFT WITH BIOABSORBABLE PINS IN ACL RECONSTRUCTION IN SHEEP.
abstract: OBJECTIVE
  To determine the initial resistance of fixation using the Rigid Fix(®) system, and compare it with traditional fixation methods using metal interference screws; and to evaluate the resistance of the fixation with the rigid fix system when the rotational position of the bone block is altered in the interior of the femoral tunnel.
  
  
  METHODS
  forty ovine knee specimens (stifle joints) were submitted to anterior cruciate ligament reconstruction (ACL) using a bone-tendon-bone graft. In twenty specimens, the Rigid Fix method was used; this group was subdivided into two groups: ten knees the pins transfixed only the spongious area of the bone block, and ten for fixation passing through the layer of cortical bone. In the twenty remaining specimens, the graft was fixed with 9mm metal interference screws.
  
  
  RESULTS
  comparison of the RIGIDFIX(®) method with the metal interference screw fixation method did not show any statistically significant differences in terms of maximum load and rigidity; also, there were no statistically significant differences when the rotational position of the bone block was altered inside the femoral tunnel. For these evaluations, a level of significance of p < 0.017 was considered.
  
  
  CONCLUSIONS
  fixation of the bone-tendon-bone graft with 2 bioabsorbable pines, regardless of the rotational position inside the femoral tunnel, gave a comparable fixation in terms of initial resistance to the metal interference screw, in this experimental model.
authors.affiliation: MSc in Surgical Clinical Medicine from the Federal University of Paraná (UFPR); Professor in the Specialization Course on Sports Traumatology and Arthroscopy,UFPR; Member of the Orthopedics and Traumatology Service, Hospital do Trabalhador, UFPR, Curitiba, PR, Brazil.
authors.forename: Mauro Batista
authors.initials: MB
authors.lastname: Albano
authors.affiliation: PhD in Mechanical Engineering; Professor in the Academic Department of Mechanics, Federal Technological University of Paraná (UTFPR), Curitiba, PR, Brazil.
authors.forename: Paulo César
authors.initials: PC
authors.lastname: Borges
authors.affiliation: MSc in Surgical Clinical Medicine from UFPR; Professor and Coordinator of the Specialization Course on Sports Traumatology,UFPR; Member of the Orthopedics and Traumatology Service, UFPR, Curitiba, PR, Brazil.
authors.forename: Mario Massatomo
authors.initials: MM
authors.lastname: Namba
authors.affiliation: PhD in Surgical Clinical Medicine from UFPR; Professor in the Specialization Course on Sports Traumatology and Arthroscopy,UFPR; Member of the Orthopedics and Traumatology Service,UFPR, Curitiba, PR, Brazil.
authors.forename: João Luiz Vieira
authors.initials: JL
authors.lastname: da Silva
authors.affiliation: Physician and Professor in the Specialization Course on Sports Traumatology and Arthroscopy,UFPR; Member of the Orthopedics and Traumatology Service,UFPR, Curitiba, PR, Brazil.
authors.forename: Francisco
authors.initials: F
authors.lastname: de Assis Pereira Filho
authors.affiliation: Physician andProfessor in the Specialization Course on Sports Traumatology and Arthroscopy,UFPR, Curitiba, PR, Brazil.
authors.forename: Edmar Stieven
authors.initials: ES
authors.lastname: Filho
authors.affiliation: PhD in Surgical Clinical Medicine. Adjunct Professor in the Department of Surgery, UFPR, Curitiba, PR, Brazil.
authors.forename: Jorge Eduardo Fouto
authors.initials: JE
authors.lastname: Matias
keywords: Anterior Cruciate Ligament; Bone-Patellar Tendon-Bone Graft; Knee; Sheep