title: The medial longitudinal arch as a possible risk factor for ankle sprains: a prospective study in 83 female infantry recruits.
abstract: BACKGROUND
  Ankle sprains are frequent, especially in athletes, soldiers, or others who perform high levels of physical activity. Although prevention is a primary goal, little is known about the risk factors. We evaluated the association of the structure of the medial arch of the foot to the occurrence of acute and recurrent ankle sprains in 83 female infantry recruits. We found no previous studies on ankle sprains in women in the English literature.
  
  
  METHODS
  Arch height was quantified using the Chippaux-Smirak index, and each arch was classified as high, normal, or low. Retrospective data were obtained from questionnaires in which the soldiers noted whether or not they had had ankle sprains in the past, the grade of the sprain, and recurrence. Prospective data were accumulated in the 4 months of basic training, during which time every ankle sprain was documented and classified according to its grade and cause.
  
  
  RESULTS
  The retrospective data showed more frequent ankle sprains in the low arch group than in the normal arch group, mainly in the right foot (RR of 2.9, p <0.05). Recurrent sprains studied retrospectively also showed that more sprains occurred in the low arch group than in the normal arch and high arch groups (RR of 10.3, p <0.05). The prospective data suggested a pattern toward the same outcome (50% in the low arch as opposed to 36% in the normal arch group, RR, 1.3), but with no statistical significance.
  
  
  CONCLUSIONS
  We concluded that a low arch of the foot might be a risk factor for ankle sprains. However, our study consisted of a relatively small population, and further studies are needed.
authors.affiliation: Meir University Hospital, Orthopaedic Division, Kfar-Saba, Israel 44281. mei-dan@bezeqint.net
authors.forename: Omer
authors.initials: O
authors.lastname: Mei-Dan
authors.forename: Gadi
authors.initials: G
authors.lastname: Kahn
authors.forename: Aviva
authors.initials: A
authors.lastname: Zeev
authors.forename: Amir
authors.initials: A
authors.lastname: Rubin
authors.forename: Naama
authors.initials: N
authors.lastname: Constantini
authors.forename: Adi
authors.initials: A
authors.lastname: Even
authors.forename: Meir
authors.initials: M
authors.lastname: Nyska
authors.forename: Gideon
authors.initials: G
authors.lastname: Mann
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D005260:Female; D005528:Foot / Q000473:pathology*; D006801:Humans; D008889:Military Personnel; D011446:Prospective Studies; D012008:Recurrence; D012189:Retrospective Studies; D012307:Risk Factors; D013180:Sprains and Strains / Q000209:etiology* / Q000473:pathology