title: Relationship of Self-Reported Ability to Weight-Bear Immediately After Injury as Predictor of Stability for Ankle Fractures.
abstract: BACKGROUND
  Determining the stability of ankle fractures, particularly Weber B fibula fractures, can be challenging. Ability to weight-bear after injury may be predictive of stability. We sought to determine whether patients' ability to weight-bear immediately after injury was an effective indicator for ankle stability following fracture.
  
  
  METHODS
  A prospective review was conducted of patients sustaining ankle fractures. Patients' ability to weight-bear after injury was elicited and correlated with ankle radiographs, which were deemed stable or unstable based on commonly used indices to assess stability.
  
  
  RESULTS
  For the entire cohort (n = 121), patients who were able to weight-bear immediately after injury were over 8 times more likely to have a stable fracture than those who could not (odds ratio [OR] = 8.6, P < .001). Positive predictive value (PPV) for being able to fully weight-bear as it related to stability was 73%. Inability to weight-bear was 85% specific among patients with an unstable fracture. When analyzing patients with radiographic isolated fibula fractures (n = 67), PPV = 82%, negative predictive value [NPV] = 53%, specificity = 79%, whereas the OR was 5.0 (P = .003) for those who could weight-bear having a stable fracture. When subanalyzing patients who presented with isolated fibula fractures and anatomic mortises (n = 43), PPV = 74%, NPV = 52%, specificity = 62%, whereas the OR was 3.6 (P = .07) for those who could weight-bear having a stable fracture.
  
  
  CONCLUSIONS
  Patients' ability to weight-bear immediately after injury was a specific and prognostic indicator for stability across a range of ankle fracture subtypes. Patients with an isolated fibula fracture and anatomic mortise were 3.6 times more likely to have a stable fracture if they were able to fully weight-bear at the time of injury. Although a patient's history does not preclude the need for appropriate imaging studies and clinical judgment, it may aid in the assessment of ankle stability following fracture.
  
  
  METHODS
  Level II, clinical diagnostic.
authors.affiliation: Harvard Combined Orthopaedic Residency Program, Boston, MA, USA.
authors.forename: Bonnie
authors.initials: B
authors.lastname: Chien
authors.affiliation: New England Baptist Hospital, Boston, MA, USA.
authors.forename: Kurt
authors.initials: K
authors.lastname: Hofmann
authors.affiliation: Carl J. Shapiro Department of Orthopaedics, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA mghorban@bidmc.harvard.edu.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghorbanhoseini
authors.affiliation: Department of Anesthesia, Boston Children's Hospital, Harvard Medical School, Boston, MA, USA.
authors.forename: David
authors.initials: D
authors.lastname: Zurakowski
authors.affiliation: Orthopaedic Trauma, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Edward K
authors.initials: EK
authors.lastname: Rodriguez
authors.affiliation: Orthopaedic Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Appleton
authors.affiliation: OrthoCarolina, Foot and Ankle Institute, Charlotte, NC, USA.
authors.forename: J Kent
authors.initials: JK
authors.lastname: Ellington
authors.affiliation: Carl J. Shapiro Department of Orthopaedics, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: John Y
authors.initials: JY
authors.lastname: Kwon
mesh_terms: D000818:Animals; D064386:Ankle Fractures; D016512:Ankle Injuries / Q000503:physiopathology*; D005360:Fibula / Q000293:injuries*; D006801:Humans; D007593:Joint Instability / Q000503:physiopathology*; D011446:Prospective Studies; D011859:Radiography; D057566:Self Report; D012680:Sensitivity and Specificity; D016474:Weight-Bearing / Q000502:physiology*
keywords: ability to weight-bear; ankle fracture; ankle stability; weightbearing radiograph