Fri., 10/9/09 Pilon/Foot & Ankle, Paper #55, 4:11 pm OTA-2009
Youtube Video Clips as a Tool for the Study of Injury Dynamics: Validating the Lauge-Hansen Ankle Fracture Classification System for In-Vivo Ankle Fractures
John Y. Kwon, MD (n); John J. Kadzielski, MD (n); Aron T. Chacko, BS (n);
Paul T. Appleton, MD (n);
Edward K. Rodriguez, MD, PhD (5A-Regenisys Orthopaedics; 8-MXO Orthopaedics);
Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA
Purpose: Lauge-Hansen’s 1950 study on cadaveric limbs still stands as the seminal work for our understanding of ankle fracture mechanism and its correlation with radiographic fracture patterns. However, recent biomechanical and radiographic studies have challenged its validity and applicability to live (in vivo) ankle fractures. We have obtained a series of video clips showing in vivo ankle fractures as they occur in real time and matched each video clip to the actual radiographic image of the injury sustained to asses if the Lauge-Hansen classification system (LH) is applicable to real in vivo injuries.
Methods: Videos were collected from www.youtube.com by using the keywords “broken ankle, ankle, tibia, fibula, break, fracture, broken, snap, dislocation.” Over 1,000 videos were reviewed for quality and visualization of the ankle injury; 240 were found to show an injury with deforming forces classifiable by the LH system. These individuals were contacted to request participation. Of 96 positive responses, we have collected to date 14 videos with corresponding radiographs. Videos and radiographs were reviewed and classified using the LH system by 2 trauma fellowship-trained surgeons and 2 orthopaedic residents in an independent blinded manner. The deforming force in the video clips was classified as supination external rotation (SER), supination adduction (SAD), pronation external rotation (PER), or pronation abduction (PAB). Radiographic fracture patterns were similarly classified. Study participants were paid $100 for participation.
Results: Of the 14 video clips reviewed, 8 had SAD-deforming trauma and 6 had PER-deforming trauma as appreciated in the videos. There was no SER- or PAB-deforming trauma appreciated in the videos. Injuries occurred as the result of skateboarding (9), bicycling (1), wrestling (2), and martial arts (2). Despite video clips being selected for severe deformation, there were 2 nonfractures. There was 1 subtalar dislocation with an SAD injury, and there were 11 true ankle fractures. When assessing ankle fractures, all 5 fractures judged by video to be SAD injuries resulted in corresponding SAD-pattern radiographic ankle fractures. Of the 6 fractures judged by video to be PER injuries, only 3 resulted in PER-pattern radiographic ankle fractures. Two PER video injuries resulted in SER ankle fracture patterns and another resulted in a PAB ankle fracture pattern.
Conclusion: Lauge-Hansen’s classification system has been the standard for relating fracture mechanisms to radiographic fracture patterns. However, when in vivo video injury clips of actual ankle fractures are matched to their corresponding radiographs, the LH system is only 73% overall accurate in predicting fracture patterns from deforming injury mechanism. All SAD injuries correlated, but only 50% of PER injuries resulted in a PER fracture pattern.
• The FDA has not cleared this drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an “off label” use). ◆FDA information not available at time of printing. Δ OTA Grant