Biomechanical Study Investigating AP Screw Orientation in Posterior Malleolar Fracture Fixationtext_resourcesPosterior malleolar fractures are common rotational ankle injuries that lack a consensus regarding surgical fixation methods. One technique is the use of AP lag screws, but the orientation of the screws has not been well-studied. The standard practice involves two screws placed parallel to the plantar surface of the foot. However, angling the screws from anterior proximal to posterior distal may provide additional biomechanical stability due to increased metadiaphyseal bone purchase proximally and more screw threads past the fracture site distally. To our knowledge, no previous studies have examined the orientation of AP lag screws in posterior malleolar fixation and its effects on biomechanical efficacy. The results of the proposed study could help bolster treatment plans and guidelines for posterior malleolar fractures. We will analyze this by accomplishing the following: (1) Determine whether AP screw orientation in posterior malleolar fixation influences biomechanical stability with cyclical loading simulating early weight bearing and (2) Evaluate whether AP proximal to distal screw orientation vs AP parallel-to-joint screw orientation in posterior malleolar fixation has improved fixation stability using incremental axial loading and load to failure. We will first create posterior malleolar fractures using fluoroscopic guidance, then randomize one specimen of each matched pair to one of the two AP screw methods for fracture fixation. We will then pot specimens, use the instron, externally rotating through the hindfoot to recreate the injury/failure biomechanics, and determine the load to failure force indicated by 2mm displacement at the fracture site as well as catastrophic failure.Katz, LucaAuthorLiu, JonathanAuthorSchilkowsky, RachelAuthorMolino, JanineAuthorHsu, RaymondAuthorBrown University. Alpert Medical School. Scholarly Concentration Program. Non-Scholarly Concentratorresearch programBiomechanicsAnkle--SurgeryAnkle--Wounds and injuries--TreatmentAnkleAnkle--Wounds and injuriesSpanish2023Non-Scholarly ConcentratorAll rights reservedIn CopyrightAll Rights Reserved