Tips and tricks for the treatment of marginal impaction in acetabular fractures.

Marginal impaction, first described by Letournel and Judet, results from impaction of the femoral head into the articular surface of the acetabulum, causing articular incongruity. Marginal impaction was originally described in the setting of posterior wall and transverse-posterior wall acetabular fractures, in which the femoral head is driven into posterior acetabulum, such as from a dashboard injury during a motor vehicle collision. As the average age of the population increases, marginal impaction of the anterior wall and acetabular dome has been increasingly described in the setting of low energy geriatric acetabular fractures. Identification and proper treatment of marginal impaction is paramount, as misdiagnosis or imperfect reduction will result in incongruity of the hip joint, rapid development of post-traumatic arthritis, and poor patient outcomes. The objective of this paper is to use case-based illustration to describe the steps to achieve anatomic reduction and stable fixation of marginal impaction to minimize development of post-traumatic arthritis.