What’s the Claim?
In the five-year follow-up of a randomized controlled trial, surgery for isolated, closed Weber B (AO 44-B1) ankle fractures with <2 mm widening of the medial clear space was no better than a walking boot in terms of patient-reported outcomes for pain and function. The group that had surgery had more major adverse events — mostly secondary surgical procedures to remove hardware, which were performed in about one in five patients.
How’s It Stack Up?
The authors of this study earlier reported the one-year results of this RCT along with a much larger parallel observational study of patients who were unwilling to be randomized. The current report at 5 years was, in essence, no difference from the findings at one year — no benefit to surgery in terms of the AAOS Foot and Ankle Questionnaire or the physical component score of the SF-12, two validated and well-chosen metrics for the purpose. The observational arm of the earlier study reinforced the findings of the RCT and dealt nicely with the commonly raised concern that patients who agree to be randomized are somehow “different” — surgery didn’t seem to offer much benefit in the one-year RCT, the one-year report of the patients who declined randomization and chose their treatments (surgery or not), nor in the current five-year report. These findings generally agree with other longer-term findings from retrospective research, as well.
What’s Our Take?
At this point, it seems pretty well accepted that absent demonstrable instability (talar shift), there is no case for surgery in most patients with these fractures. Those who disagree will point to two concerns about this study — about half of the patients were lost to follow-up, and the authors did not obtain repeat radiographs to see whether surgery reduced the development of arthritic changes in these patients. To these critiques we offer the following responses: (1) The missing did not differ from the accounted for in terms of key baseline variables, (2) the missing and the accounted for here at 5 years did not differ from one another in terms of outcomes scores at one year (they looked back at the results from the earlier study, in which nearly 90% of patients were accounted for), and (3) the outcomes scores in the nonsurgical group of the current study were so high that it seems unlikely that clinically important arthritis is present. In light of the findings from this study — the largest and longest RCT we know of on the topic — it seems reasonable to recommend a walking boot for most patients with these injuries.
O'Keefe R, Naylor JM, Symes MJ, Harris IA, Mittal R. Minimum 5-Year Follow-up Results: CROSSBAT (Combined Randomised and Observational Study of Surgery vs No Surgery for Type B Ankle Fracture Treatment). Foot Ankle Int. 2022;43:1517-1524.