The aim of this study was to evaluate the long-term outcomes of patients who had sustained an unstable ankle fracture with a posterior malleolus fracture (PMF) and without (N-PMF).

Adult patients presenting to a single academic trauma centre in Edinburgh, UK, between 2009 and 2012 with an unstable ankle fracture requiring surgery were identified. The primary outcome measure was the Olerud Molander Ankle Score (OMAS). Secondary measures included Euroqol-5D-3L Index (Eq5D3L), Euroqol-5D-VAS and Manchester Oxford Foot Questionnaire (MOXFQ).

There were 304 patients in the study cohort. The mean age was 49.6 years (16.3–78.3) and 33% (n=100) male and 67% (n=204) female. Of these, 67% (n=204) had a PMF and 33% did not (n=100). No patient received a computed tomography (CT) scan pre-operatively. Only 10% of PMFs (22/204) were managed with internal fixation. At a mean of 13.8 years (11.3 – 15.3) the median OMAS score was 85 (Interquartile Range 60 – 100). There was no difference in OMAS between the N-PMF and PMF groups (85 [56.25 – 100] vs 85 [61.25 – 100]; p = 0.580). There was also no difference for MOXFQ (N-PMF 7 [0 – 36.75] vs PMF 8 [0–38.75]; p = 0.643), the EQ5D Index (N-PMF 0.8 [0.7 – 1] vs PMF 0.8 [0.7 – 1]; p = 0.720) and EQ5D VAS (N-PMF 80 [70 – 90] vs PMF 80 [60 – 90]; p = 0.224).

The presence of a PMF does not affect the long-term patient reported outcomes in patients with a surgically managed unstable ankle fracture.