To characterize the fracture-line distribution and geometric features of acetabular roof column and wall fractures (A3 injuries) using three-dimensional mapping.
Approach:
Study Design: A multicenter retrospective study was conducted involving 89 patients with A3 injuries, from which 46 surgically treated patients with adequate CT data were included.
CT Processing: CT data were reconstructed in Mimics and processed in 3-Matic for various analyses including fragment separation, virtual reduction, and surface-area measurement.
Fracture Mapping: Fracture trajectories were registered to a standardized hemipelvic template to generate subtype-specific fracture maps and an overall heat map.
Key Findings:
A3.1 fractures exhibited shorter perifragment fracture-boundary length but greater fragment displacement and angular change.
A3.2 and A3.3 fractures showed longer cranial trajectories and larger extra-fossa surface involvement.
No significant difference in intra-fossa surface area was found among the subtypes.
Classification agreement was substantial, and quantitative measurements demonstrated excellent reliability.
Interpretation:
Limitations:
Findings are primarily applicable to more displaced or complex A3 injuries and may not generalize to minimally displaced or nonoperatively managed injuries.
The study included only surgically treated patients with adequate CT data.
