Radiographic Changes After Pubic Symphysis Plating and Their Clinical Relevance: An Exploratory Longitudinal Cohort Study.

BACKGROUND

Pubic symphysis plating is a common method for stabilizing traumatic pubic symphysis disruptions, yet reported rates of implant failure vary widely in the literature. This variability may reflect inconsistent definitions and failure to distinguish clinically significant early construct failure from later asymptomatic postoperative radiographic changes.

METHODS

We performed a retrospective observational study of 30 patients with traumatic pubic symphysis disruption without associated fractures of the pubic body or pubic rami treated with open reduction and plate fixation. Pubic symphysis distance (PSD) was measured on admission CT, immediate postoperative anteroposterior pelvic radiographs, and follow-up CT scans obtained at 3, 6, and ≥12 months. Early mechanical failure, qualitative radiographic signs of implant loosening, and radiographic loss of reduction were predefined. Non-parametric tests were used to compare patients with and without early mechanical failure and to evaluate longitudinal PSD changes; analyses of potential associated factors were exploratory.

RESULTS

Early mechanical failure occurred in 4 patients (13.3%) within 30 days and presented as an acute symptomatic event with imaging-confirmed construct compromise requiring revision. In exploratory univariable analysis, early failure was more frequent in female patients and in those with obesity or osteoporosis, although these findings should be interpreted cautiously given the very small number of events. PSD changed significantly over time (p < 0.001), with minimal increase during the first 3 months, greater widening between 3 and 6 months, and little additional change thereafter. Qualitative radiographic signs of implant loosening and widening were observed in 8 patients (26.7%) during follow-up without clinically documented pain, instability, or need for revision. No clear association was demonstrated between PSD widening and final functional outcome measured by the Majeed score, although these analyses were limited by sample size and wide confidence intervals.

CONCLUSIONS

In this retrospective cohort, postoperative radiographic widening and qualitative signs of implant loosening were not by themselves associated with clinically evident failure requiring revision during the available follow-up. Early failure was identified by acute clinical symptoms with imaging-confirmed construct compromise, whereas delayed widening was often observed without clinically documented pain, instability, or reoperation. These findings suggest that postoperative imaging should be interpreted together with symptoms and overall pelvic stability, while recognizing the methodological limitations of the study.