title: Manual Stress Ankle Radiography Has Poor Ability to Predict Deep Deltoid Ligament Integrity in a Supination External Rotation Fracture Cohort.
abstract: Stress ankle radiographs are routinely performed to determine deep deltoid ligament integrity in supination external rotation (SER) ankle fractures. However, variability is present in the published data regarding what medial clear space (MCS) value constitutes a positive result. The purposes of the present study were to evaluate the diagnostic accuracy of different MCS cutoff values and determine whether this clinical test could accurately discriminate between patients with and without a deep deltoid ligament disruption. MCS measurements were recorded for stress ankle injury radiographs in an SER ankle fracture cohort. Preoperative ankle magnetic resonance imaging studies, obtained for all patients, were then read independently by 2 musculoskeletal attending radiologists to determine deep deltoid ligament integrity. The MCS measurements were compared with the magnetic resonance imaging diagnosis using receiver operating characteristic analyses to determine the sensitivity, specificity, and optimal data-driven cutoff values. SER II-III patients demonstrated a mean stress MCS distance of 4.3 ± 0.98 mm compared with 5.8 ± 1.76 mm in the SER IV cohort (p < .001). An analysis of differing MCS positive cutoff thresholds revealed that a stress MCS of 5.0 mm maximized the combined sensitivity and specificity of the external rotation test: 65.8% sensitive and 76.5% specific. Using the receiver operating characteristic curve analysis of the MCS measurement, the calculated area under the curve was 0.77, indicating inadequate discriminative ability for diagnosing SER pattern fractures with or without a deep deltoid ligament tear. Judicious use of additional diagnostic testing in patients with a stress MCS result between 4.0 mm and 5.5 mm is warranted.
authors.affiliation: Resident, Orthopaedic Trauma Service, Hospital for Special Surgery, New York, NY. Electronic address: Schottel@gmail.com.
authors.forename: Patrick C
authors.initials: PC
authors.lastname: Schottel
authors.affiliation: Resident, Orthopaedic Trauma Service, Hospital for Special Surgery, New York, NY.
authors.forename: Peter D
authors.initials: PD
authors.lastname: Fabricant
authors.affiliation: Department of Orthopaedic Surgery, Landstuhl Regional Medical Center, Landstuhl, Germany (United States Air Force).
authors.forename: Marschall B
authors.initials: MB
authors.lastname: Berkes
authors.affiliation: Resident, Orthopaedic Trauma Service, Hospital for Special Surgery, New York, NY.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Garner
authors.affiliation: Fellow, Orthopaedic Trauma Service, Harborview Medical Center, Seattle, WA.
authors.forename: Milton T M
authors.initials: MT
authors.lastname: Little
authors.affiliation: Chief, Emergency and Musculoskeletal Imaging, and Associate Professor, Department of Clinical Radiology, New York Presbyterian Hospital/Weill Cornell Medical College, New York, NY.
authors.forename: Keith D
authors.initials: KD
authors.lastname: Hentel
authors.affiliation: Associate Attending Physician, Department of Clinical Radiology, Hospital for Special Surgery, New York, NY.
authors.forename: Douglas N
authors.initials: DN
authors.lastname: Mintz
authors.affiliation: Director, Orthopaedic Trauma Service, Hospital for Special Surgery and Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY.
authors.forename: David L
authors.initials: DL
authors.lastname: Helfet
authors.affiliation: Associate Director, Orthopaedic Trauma Service, Hospital for Special Surgery and Weill Cornell Medical College, New York Presbyterian Hospital, New York, NY.
authors.forename: Dean G
authors.initials: DG
authors.lastname: Lorich
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D064386:Ankle Fractures / Q000000981:diagnostic imaging* / Q000473:pathology*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008023:Ligaments, Articular / Q000000981:diagnostic imaging / Q000293:injuries* / Q000473:pathology; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D011859:Radiography; D015203:Reproducibility of Results; D012399:Rotation; D012680:Sensitivity and Specificity; D013484:Supination; D055815:Young Adult
keywords: SER; ankle fracture; deep deltoid ligament; stress ankle radiography; supination external rotation