Posterior wall fractures may be associated with both-column acetabular fractures. Considering the differences in the pattern of these fractures in contrast to isolated posterior wall fractures, it is currently unclear whether they can be ignored or need to be addressed surgically.

Stable posterior wall fractures can be skilfully ignored in patients with both-column acetabular fractures operated by an ilioinguinal approach.

We retrospectively reviewed 49 consecutive patients who were treated for both-column acetabular fractures between the years 2009 and 2018. Considering the association of posterior wall fractures, we divided the cohort into two groups: Group 1 (n=29): absence of posterior wall fractures; and Group 2 (n=20): presence of posterior wall fractures, subsequently treated while skilfully ignoring stable posterior wall fracture according to our criteria. Intergroup comparison of radiologic and clinical outcomes and multiple linear regression for predictors of clinical outcomes were analysed.

No significant intergroup difference in quality of reduction, post-traumatic osteoarthritis grade, or clinical outcome was noted. Poor post-traumatic osteoarthritis grade and poor quality of reduction of both acetabular columns were significant predictors of clinical outcomes in patients with both-column acetabular fractures. Whether posterior wall fracture was associated and skilfully ignored was unrelated to clinical outcomes.

Posterior wall fractures associated with both-column acetabular fractures can be successfully ignored if the posterior wall fragment is adequately attached to the acetabulum through the labrocapsular complex of the hip joint, and the hip-joint-congruency in the presence of<2-mm step-off and 3-mm gap.

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