Incidence of post-traumatic osteoarthritis in 44B ankle fractures: Analysis of risk factors

The purpose of this study was to analyse the clinical and radiographic data of a consecutive series of patients treated surgically for AO/OTA 44B ankle fracture at Ferrara University Hospital, Italy, with a view to identifying risk factors contributing to worse clinical and radiographic outcomes with a minium follow up of 6 years.

For each patient the following data were recorded: gender, age, Body Mass Index (BMI), follow up (months), previous ankle sprains, type of work, Kellgren-Lawrence (K&L) score, AO/OTA classification for ankle fracture, Foot and Ankle Disability Index (FADI score), ankle dislocation, syndesmotic transfixation, quality of reduction.

FADI score in patients with AO/OTA 44B1 fracture was 95.5±7.5, in 44B2 it was 90.0±8.4 and in 44B3 it was 84.0±13.0 (p25 it was 88.6±11.4 (p=0.047 95%I.C. 0.01-8.10). In case of fracture-dislocation there was a statistically significant difference in the FADI (94.4±6.0 vs 85.8±11.98)(P=0.002 95% I.C. 0.01-8.9). In the former group, there was a statistically significant difference in the ​the K&L (1.97±0.65 vs 2.63±0.85) (P=0.006 95% I.C 0.01-1.00).Finally, the quality of the reduction was a statistically significant parameter in both the FADI and K&L (P=0.012 95% I.C. 0.90-10.60 and P=0.012 95%I.C. 0.01-1.00 respectively).

The most influential risk factors for worse outcome in AO/OTA 44B ankle fractures were found to be BMI, injury severity, fracture-dislocation and reduction quality.