Twenty-Two-Year Follow-up of Pronation External Rotation Type III-IV (OTA Type C) Ankle Fractures: A Retrospective Cohort Study

Long-term evaluation protocolled treatment of pronation external rotation (PER) type III-IV (OTA type C) ankle fractures. Level III retrospective cohort study. Level I trauma center. A consecutive series of 98 patients with PER III-IV ankle fractures between 1985 and 1990. Stable fractures with tibiotalar congruity were treated conservatively, whereas osteosynthesis was performed in unstable and displaced fractures to restore tibiotalar congruity. Outcome parameters were (1) functional outcome questionnaire (Olerud score), (2) physical evaluation (loaded dorsal range of motion), (3) functional impairment (AMA Guides, 5th ed.), and (4) radiographic evaluation (Cedell score, medial clear space widening, and osteoarthritis). After a median of 22 years, follow-up was achieved in 95% (n = 60) of living patients. Four patients had a true PER III injury, 5 patients had an unclear injury (between PER III and IV), and 51 patients (85%) sustained a PER IV injury. Excellent or good results were found in 90% of patients (Olerud score). Functional impairment, expressed as percentage of Whole Person Impairment, varied between 0% and 3%. Patients treated operatively and conservatively had statistically equivalent scores. The long-term result of surgical treatment of PER ankle fractures is “good” or “excellent” in the majority of patients. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.