Articular impactions in acetabular fractures.

Impactions of the articular surface are relevant prognostic parameters in the treatment of acetabular fractures. Posterior marginal impactions and acetabular dome impactions may occur depending on the direction of the force vectors during trauma. Posterior marginal impactions are mainly observed in posterior fracture dislocations, while acetabular dome impactions are frequently seen in the elderly with the hip joint in extension during trauma. Femoral head impactions are also frequently associated with acetabular fractures, mainly in fracture dislocations and transverse acetabular fractures. CT scans using thin slices are mandatory in order to preoperatively identify acetabular and femoral head impactions. Intraoperatively, the reduction techniques depend on the type of marginal impaction. Posterior impactions are usually addressed via a posterior approach by applying femoral traction under direct visualization or even by performing surgical hip dislocation. Acetabular dome impactions may be reduced using the fracture lines or by creating a cortical window. Reduction is followed by filling the void with bone or bone substitutes supported by raft screws. No clear treatment recommendations for femoral head impactions are given in the literature.