SLR - May 2017 - Vanessa Cardenas
Testing Is Unnecessary for Unimalleolar Supination-External Rotation Ankle
Fractures with Minimal Fracture Displacement on Lateral Radiographs
Reference: Simo Nortunen, MD, Hannu-Ville Leskela,
MD, PhD, Heidi Haapasalo, MD, PhD, Tapio Flinkkila, MD, PhD, Pasi Ohtonen,
MSc, and Harri Pakarinen, MD, PhD. Dynamic Stress Testing Is Unnecessary for
Unimalleolar Supination-External Rotation Ankle Fractures with Minimal Fracture
Displacement on Lateral Radiographs. J Bone Joint Surg Am. 2017 99:482–7.
Reviewed By: Vanessa
Residency Program: Temple
University Hospital, Philadelphia, PA
Podiatric Relevance: Foot and ankle surgeons
encounter ankle fractures pathology in daily practice. The controversy of when
it is appropriate to conservatively or surgically address lateral malleolar
fractures without talar displacement is present in the literature and in practice.
Dynamic/stress radiographs are tools utilized to ascertain the degree of
instability of these injuries and to make operative versus conservative
treatment decisions. This study aims at categorizing factors in standard ankle
radiographs that contribute to the stability of the ankle mortise in patients
with isolated SER fractures of the lateral malleolus.
Methods: Level IV Prospective study of 286 patients
from two trauma centers. Nonstress radiographs from skeletally mature patients
(> 16 y/o) of the mortise and lateral views, without medial clear space
widening or incongruity, were collected. Two senior orthopaedic trauma surgeons from
the two trauma centers performed manual external rotation stress test
radiographs for stability reference. They also assessed fracture morphology at
which time their measurements were blinded from each other (as well as results
from the stress test).
Results: Two hundred seventeen patients had a stable injury (medial
clear space of < 5 mm) based on the external rotation stress radiographs.
Factors predicting stable ankle injury: posterior diastasis < 2 mm on lateral
radiographs and when this factor and only two fracture fragments were present,
the probability of a stable ankle mortise was 0.98 in 48 females and 0.994 for
Conclusion: Based on the results of the study, in noncomminuted
lateral malleolar fractures, when the fibula is posteriorly displaced < 2 mm on the lateral view, the ankle
mortise can be diagnosed as stable without the need for stress radiographs.