Evaluation of Handling and Possible Complications Related to the Newly Developed Angular Stable Locking System (ASLS)

In many cases, the existing locking bolts and screws in intramedullary nails do not provide sufficient stability. Due to the play between screw and nail, the reduction can be lost and the instability can result in malunions, nonunions, or pseudoarthrosis. Consequently, secondary angular fracture dislocation (defined as a difference of the angle of 10° or more from the post-operative to the follow-up x-rays) can be observed in approximately 30% of patients after conventional intramedullary nailing of proximal third tibial fractures and in approximately 0-2% in patients with distal third tibial fractures. Therefore, an Angular Stable Locking System for Intramedullary Nails (ASLS) was developed to reduce the risk of secondary loss of reduction by providing axial and angular stability. ASLS provides angular stable fixation between nails and screws with resorbable sleeves used as dowels in the nail locking holes. The present study evaluates the handling of ASLS and the surgeon's compliance as well as any complications occurring during the baseline and the follow-up period in patients with proximal and distal tibial, femoral and humeral fractures treated with intramedullary nails. Furthermore, the relationship of any occurred complications to ASLS will be assessed.