Thurs., 10/8/09 Pelvis & Acetabulum, Paper #37, 4:44 pm OTA-2009
Value of Three-Dimensional Computed Tomography in Classifying Acetabular Fractures during Orthopaedic Residency Training
Jeffrey P. Garrett, MD (n); Lawrence X. Webb, MD (7-FOT); Joseph A. Veneziano, MD (n);
Eben A. Carroll, MD (n);
Wake Forest University Health Sciences, Winston-Salem, North Carolina, USA
Purpose: This study was designed to evaluate the value of three-dimensional computed tomography (3D-CT) in enhancing orthopaedic residents’ ability to mentally conceptualize and classify complex fractures of the pelvis and acetabulum. It is hypothesized that 3D-CT imaging is a more effective tool for classifying acetabular fractures for orthopaedic residents, than the combination of plain radiographs and two-dimensional CT (2D-CT) alone.
Methods: Twenty acetabular fracture cases were prepared and organized in PowerPoint format. The classic fracture patterns described by Letournel-Judet were represented. A case consisted of either radiographs (AP, Judet) and 2D-CT or 3D-CT alone. Case order was randomly generated. A “quiz” was then given in grand-rounds lecture format. Participants were given 90 seconds to review radiology and 15 seconds to classify the fracture pattern. A fracture diagram sheet was given for use during the quiz. 31 orthopaedic residents representing PGY1-5 and 19 orthopaedic traumatologists participated in the study, groups 1 and 2 respectively.
Results: Both groups showed improved results classifying acetabular fractures with 3D-CT imaging. Orthopaedic traumatologists were 1.26 times more likely and residents 1.62 times more likely to correctly classify acetabular fractures with 3D-CT than with plain radiographs and 2D-CT alone. Using the z-test, the improvement in scores using 3D-CT versus plain radiographs and 2D-CT was most evident in junior residents (PGY1-3), where the difference was statistically significant (P ≤0.001). The difference for senior residents (PGY4-5) and trauma attending physicians did not reach statistically significance (P ≤0.07). Also, the difference between senior and junior residents in classifying fractures with 3D-CT was not statistically significant, whereas seniors were significantly better than juniors at classifying fractures with radiographs and 2D-CT alone (P ≤0.05). Orthopaedic traumatologists were significantly better at classifying acetabular fractures than junior residents using both 3D and 2D imaging (P ≤0.01); however, the difference between traumatologists and senior residents did not reach statistical significance (P ≤0.1). The most commonly misclassified fractures were T-type and nondisplaced anterior wall, posterior column, and transverse patterns.
Conclusion: 3D-CT imaging is an effective tool for understanding the complex spatial anatomy of the pelvis and acetabulum. In our study, this benefit was most pronounced at the junior orthopaedic resident level; however, 3D-CT imaging also improved accurate classification for senior residents and orthopaedic traumatologists. 3D-CT was also shown to be beneficial in identifying subtle, nondisplaced fracture lines. As residents gain a better understanding of pelvic anatomy, 3D-CT imaging can be an effective educational tool for teaching surgical approaches and fracture fixation using templating and virtual fracture reduction models.
• 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