Clinical utility of a stability-based ankle fracture classification system

OBJECTIVE: Neither of the ankle fracture classification systems (Lauge-Hansen or Weber) in widespread use today is prognostic. To test the hypothesis that ankle fracture prognosis is dependent on initial biomechanical stability, an alternative classification system created using stability-based treatment criteria was developed on the basis of a structured analysis of the ankle fracture literature. DATA SOURCES: All English-language papers reporting on ankle fractures (searched using the terms "ankle + fracture") published between 1966 and 2005 with available online abstracts via PubMed were screened. STUDY SELECTION: Abstracts were manually screened for inclusion using the following criteria: (1) there were at least 2 groups of patients categorized on the basis of either fracture configuration or treatment and (2) data was reported in sufficient detail to permit interstudy comparisons. DATA EXTRACTION: Each included paper was abstracted into a computerized database for consistent data capture. Data elements included the following: fracture classification, stability definitions, surgical indications, patient follow-up parameters, and outcome measures. Ankle fractures were also stratified into stable and unstable groups using predefined stability criteria, and the outcome measures were re-analyzed. DATA SYNTHESIS: Wilcoxon matched-pairs signed-rank test was used for statistical comparisons, assigning statistical significance to 2-tailed tests with P < 0.05. CONCLUSIONS: The results support the hypothesis that a stability-based ankle fracture classification system can be prognostic. For unstable ankle fractures, the radiographic outcomes were better after surgery, when the decision for surgery was made on the basis of stability (P = 0.0173). Overall, non-operative treatment results were also better with stability-based treatment (P = 0.0299).