Biomechanical Evaluation of Mini-Fragment Hardware for Supination External Rotation Fractures of the Distal Fibula. Issue 2 (April 2013)

• Record Type: Journal Article
• Authors: Bariteau, Jason T.; Blankenhorn, Brad D.; Lareau, Craig R.; Paller, David J.; DiGiovanni, Christopher W.
• Is Part Of: Foot & ankle specialist. Volume 6:Issue 2(2013)
• Page Start: 88
• Page End: 93
• Publication Date: 2013-04
• Subjects: biomechanical fixation -- simulated lateral malleolus fracture -- osteoporotic synthetic bone -- plate-screw construct; Podiatry -- Periodicals; Orthopedics -- Periodicals; Foot -- Diseases -- Periodicals; Foot -- Surgery -- Periodicals; Ankle -- Surgery -- Periodicals; 617.585
• DOI: 10.1177/1938640013477130
• Languages: English
• ISSNs: 1938-6400

Abstract

Background . Supination external rotation distal fibula fractures are common, requiring fixation when associated with talar displacement. Subcutaneous distal fibula hardware may become painful, necessitating operative removal. We hypothesize that mini-fragment and small-fragment constructs will demonstrate similar biomechanical stability. Methods . A biomechanical comparison was performed in synthetic osteoporotic sawbones. The first arm compared two 2.4-mm lag screws with one 3.5-mm lag screw for fixation of a simulated supination external rotation distal fibula fracture. The second arm compared a 2.4-mm plate-screw construct with a 3.5-mm lag screw and one-third tubular neutralization plate. During torsional testing, torque and displacement were recorded, and stiffness and peak torque were determined. Results . Differences in mean stiffness and mean load at failure were not statistically significant with lag screw–only fixation. The 3.5-mm plate-screw construct outperformed the 2.4-mm plate-screw construct, but neither mean stiffness nor mean load at failure were statistically significantly different. Dynamic testing also demonstrated similar results. Conclusion . Our data suggest that isolated 2.4-mm screws function similarly to one 3.5-mm screw. Although the 3.5-mm plate-screw construct was stiffer, mean load at failure was equivalent for the 2 constructs. These data provide biomechanical evidence to support further investigation in the use of mini-fragment hardware for distal fibula fracture fixation. Levels of Evidence: Therapeutic, Level V