Comparing Functional Outcomes After Injury-Specific Fixation of Posterior Malleolar Fractures and Equivalent Ligamentous Injuries in Rotational Ankle Fractures.

OBJECTIVES

To evaluate the effect of posterior bony versus ligamentous injury pattern on functional outcomes in operatively treated rotational ankle fractures.

DESIGN

Retrospective cohort analysis of prospective registry.

SETTING

Academic Level I trauma center.

PATIENTS/PARTICIPANTS: Operatively treated supination external rotation IV and pronation external rotation IV ankle fractures.

INTERVENTION

Lateral malleolus plate fixation with either posterior malleolus (PM) plate fixation or posterior inferior tibiofibular ligament (PITFL) repair.

MAIN OUTCOME MEASUREMENTS

Foot and ankle outcome scores at minimum 12 months postoperatively.

RESULTS

One hundred seventy-eight fractures were treated with injury-specific anatomic fixation of a PM fracture (n = 122) or torn PITFL (n = 56). The PM group was significantly older, contained more women, and had lower mean body mass index versus the PITFL group. There was a higher rate of medial malleolar fracture in the PM group; other fracture and baseline characteristics were similar between groups. Univariate and multivariable analysis revealed no difference in foot and ankle outcome scores for any of the 5 summary domains (symptoms, pain, activities of daily living, sports, or quality of life) at the time of most recent follow-up. The median length of follow-up was 16.3 and 12.8 months in the PM and PITFL groups, respectively.

CONCLUSIONS

In our cohort of ankle fractures, we have demonstrated comparable outcomes in stage IV rotational ankle fractures with and without PM fractures, indicating that the presence of a PM fracture may not result in inferior outcomes compared with ligamentous equivalent injuries if these fractures are addressed in an injury-specific manner.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.