OBJECTIVE: This report considers the results of the applicability test of a modified dynamic hip system developed by the authors, which allows either the manipulation or the exchange of the sliding screw, without the need to remove the plate and take all the system apart in order to change its size or position. METHODS: Five modified plates - DHS-AF - manufactured with austenitic stainless steel ASTM F 138, with 4 holes and a 135o angle were inserted in five segments of synthetic bone of proximal femur (Synbone). All implants were fixed to the femur following the surgical techniques described by AO foundation (Arbeitsgemeinschaft für Osteosynthesefragen). RESULTS: The modified dynamic hip system (DHS-AF) allowed ease in handling and exchange of sliding screw without the need for plate removal. CONCLUSION: In vitro test of the applicability of DHS-AF afforded promising results and led us to believe that after biomechanical evaluation to confirm its safety it may be reproduced in vivo.
Hip fractures; Orthopedic nails; Bone screws
