What proportion of patients eventually require joint fusion following simple ankle fractures?

G. Williams, D. Withers, J. Ballester, D. Bailey

Introduction: The literature contains few outcome studies providing long term follow up for ankle fractures, to our knowledge no studies have defined the medium to long term probability of significant further surgery for this group of patients.

Methods: Using our institutions coding database we identified a cohort of patients (n = 2137) treated for ankle fractures over a 10 year period (Jan 2001 to Dec 2011). Primary data of interest was collected in respect to whether the fracture was managed conservatively or with open reduction internal fixation (ORIF) and further procedures each patient underwent at our institution.

Results: 73% of the identified fractures were managed non-operatively (n = 1552), 28% (n = 585) underwent ORIF. Of patients treated with ORIF, 58 (8.8%) required metalwork removal. Ankle joint fusion was the eventual outcome for 15 patients (0.7%). 10 patients required ankle joint injections (0.5%) and 2 patients underwent ankle arthroscopy following their fracture (0.1%). Significantly more of the patients requiring eventual joint fusion were from the ORIF group (p = 0.001 Pearson Chi-Squared test, n = 10 vs 5 patients, relative risk 5.3, CI 1.7-17.7). Mean time to fusion or arthroscopy was at 23months (range 1-50months) and 30months (range 9-52months) respectively.

Conclusion: It is practical to assume that more serious fracture patterns would prompt treatment with ORIF and be more likely to result in subsequent ankle arthritis and eventual fusion. Our data supports this hypothesis as the relative risk for ankle fusion was over five times higher for fracture patterns treated with ORIF. Patients can be reassured that overall the probability for significant surgical procedures other than metal work removal is low however our sample may underestimate the additional surgical morbidity and fusion rate.