Serial Radiographs Do Not Change the Clinical Course of Nonoperative Stable OTA/AO 44-B1 Ankle Fractures

SLR - October 2017 - Andrew J. Ott

Reference: Marchand L.S., Working Z.M., Rane A.A., Jacobson L.G., Kubiak E.N., Higgins T.F., Rothberg D.L. Serial Radiographs Do Not Change the Clinical Course of Nonoperative Stable OTA/AO 44-B1 Ankle Fractures. JOT. 2017 May; 31(5): 264–269.

Scientific Literature Review

Reviewed By: Andrew J. Ott, DPM
Residency Program: New York Presbyterian/Queens

Podiatric Relevance: Rotational ankle injuries are a common pathology encountered by the podiatric physician. If a fracture of the ankle is found, determining whether the fracture pattern is stable or unstable is of utmost importance. If the fracture pattern is found to be stable, as in 44-B1 fractures, serial radiographs may be unnecessary.  

Methods: Retrospective review article of 134 patients with isolated lateral malleolar ankle fractures classified as OTA/AO 44-B1 (SER II/weber B fractures). Inclusion criteria were only fractures with isolated 44-B1 injuries with proven ankle stability (<5 mm medial clear space) on manual external rotation stress test. Stress test had to be documented on a mortise radiograph (15 to 20 degrees internal rotation) performed by an orthopaedic resident or attending, and a minimum of six weeks of follow-up was necessary. Exclusion criteria were any patients managed by nonorthopaedic trained providers, those without stress examination and those who did not have a mortise radiograph obtained on their initial evaluation. Two radiographic variables were measured on the mortise view. The medial clear space was measured in millimeters from the lateral boarder of the medial malleolus to a parallel line at the medial talus one-half of the distance between the talar dome and inferior aspect of the medial articular surface. Mueller-Nose distance was measured from the medial boarder of the fibula parallel to the superior lateral articular aspect of the talar dome in millimeters.

Results: Of the 134 patients with 44-B1 fracture pattern, zero patients progressed to surgery for loss of reduction or any other cause. The mean medial clear space was 3.4 mm at initial evaluation and 3.3 mm on average at final follow-up. The Mueller nose distance at the time of injury was 3.5 mm and 3.5 mm on average at the time of final follow-up.

Conclusions: No patients progressed to surgery at a mean follow-up of 82 days for isolated OTA/AO 44-B1 fractures. Serial radiographic measurements did not show any significant changes from the time of initial injury to final follow-up evaluation. No displacement in the ankle mortise was found in those fractures with negative external rotation stress tests throughout follow-up examination. There is no current literature or evidence to suggest the use of serial radiographic examination in stable 44-B1 ankle fractures. Manual external rotation stress test is reliable in predicting stability of the ankle joint in patients with a 44-B1 fracture pattern. Serial radiographic examination in these patients should be reserved for high-risk patients, those with worsening of pain or those who are noncompliant with weightbearing status.