Should discontinuity of the osteotomy site 1 year after periacetabular osteotomy be diagnosed as delayed union and not non-union?

The present study demonstrated that even if discontinuity is present at the osteotomy site or stress-fractured inferior pubic ramus and posterior column 1 year post-periacetabular osteotomy, continuity can subsequently occur at these sites. The findings suggest that discontinuity 1 year postoperatively should be defined as delayed union rather than non-union. We also identified postoperative stress fracture in the inferior pubic ramus as a risk factor for discontinuity at the pubic osteotomy site at a mean time of 3.2 years after periacetabular osteotomy.