title: Extravaginal testicular torsion: a clinical entity with unspecified surgical anatomy.
abstract: OBJECTIVE
  To review and evaluate the anatomical definitions of perinatal extravaginal torsion (EVT) of the testis.
  
  
  METHODS
  An extensive review of the literature was made to reveal the prevalent anatomical background predisposing to EVT. Gross appearance of twisted testes obtained during surgery for 14 cases of EVT was used to test the validity of the above theories.
  
  
  RESULTS
  The most commonly accepted suggestions describe an EVT within dartos muscle that includes all layers of spermatic cord or an EVT outside parietal layer of tunica vaginalis within internal spermatic fascia. However, both of them were found inadequately documented, while a large volume of controversial data has been accumulated, that raises doubts regarding the validity of such definitions. The gross appearance of twisted testes failed to confirm both an EVT including all layers of the spermatic cord and also an EVT outside tunica vaginalis as possible mechanisms of torsion.
  
  
  CONCLUSIONS
  The anatomical basis of EVT remains unclear and further investigation is required.
authors.affiliation: Department of Pediatric Surgery, University Hospital of Heraklion, Greece. jkyriazis@gmail.com
authors.forename: Iason D
authors.initials: ID
authors.lastname: Kyriazis
authors.forename: John
authors.initials: J
authors.lastname: Dimopoulos
authors.forename: George
authors.initials: G
authors.lastname: Sakellaris
authors.forename: Jurgen
authors.initials: J
authors.lastname: Waldschmidt
authors.forename: George
authors.initials: G
authors.lastname: Charissis
mesh_terms: D006801:Humans; D007231:Infant, Newborn; D008297:Male; D012189:Retrospective Studies; D013086:Spermatic Cord Torsion / Q000209:etiology / Q000601:surgery*