title: Does Foot Position and Location of Measurement Influence Ankle Medial Clear Space?
abstract: OBJECTIVE
  There is still controversy regarding normal and abnormal values of the medial clear space (MCS) of the ankle. The aim of this study was to assess how much different degrees of plantar flexion, with and without stress, influenced the MCS.
  
  
  METHODS
  We submitted 30 volunteers to 6 different anteroposterior ankle radiographs in the following positions: neutral, neutral with external rotation stress, physiologic plantar flexion (FPF), physiologic plantar flexion with external rotation stress, maximum plantar flexion (MPF), and maximum plantar flexion with external rotation stress. The MCS oblique (MCSo) and perpendicular (MCSp) were measured in all images by an experienced foot and ankle surgeon.
  
  
  RESULTS
  The data showed that the position of the foot does influence the value of MCSp and MCSo ( P < .05), except for 3 comparisons. MCSo did not change between FPF with stress and MPF with stress. MCSp did not change in 2 situations: between FPF and neutral with stress and between MPF and FPF with stress.
  
  
  CONCLUSIONS
  This study is unique in showing that different ways of positioning the foot and performing stress radiographs results in different MCS values and that these values differ depending on the anatomical site where they are measured.
  
  
  METHODS
  Diagnostic, Level IV.
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Daniel
authors.initials: D
authors.lastname: Baumfeld
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Tiago
authors.initials: T
authors.lastname: Baumfeld
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: João
authors.initials: J
authors.lastname: Cangussú
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Benjamim
authors.initials: B
authors.lastname: Macedo
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Thiago Alexandre Alves
authors.initials: TAA
authors.lastname: Silva
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Fernando
authors.initials: F
authors.lastname: Raduan
authors.affiliation: Hospital das Clínicas (UFMG).|Belo Horizonte, Brazil (DB, TB).|Hospital de Base Dr. Ary Pinheiro, Porto Velho, Brazil (JC).|Hospital Felício Rocho, Belo Horizonte, Brazil (BM).|Hospital Madre Teresa, Belo Horizonte, Brazil (TAAS).|UNIFESP, Escola Paulista de Medicina, Sao Paulo, Brazil (FR, CN).
authors.forename: Caio
authors.initials: C
authors.lastname: Nery
mesh_terms: D000328:Adult; D016512:Ankle Injuries / Q000000981:diagnostic imaging*; D000843:Ankle Joint / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D015331:Cohort Studies; D005260:Female; D005528:Foot / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D056888:Patient Positioning; D011187:Posture; D011859:Radiography / Q000379:methods; D016059:Range of Motion, Articular / Q000502:physiology; D012016:Reference Values
keywords: deltoid ligament rupture; medial clear space; plantar flexion; stress radiograph; supination-external rotation ankle fractures