title: [Anatomical study about the posterior coaxial portals via posterior tibial tendon sheath for ankle arthroscopy].
abstract: OBJECTIVE
  To conduct the anatomical study about the posterior coaxial portals via posterior tibial tendon (PTT) sheath for ankle arthroscopy.
  
  
  METHODS
  Coaxial portals were established in 20 ankles by K-wires which were left in place for distance measurement between them and the posterior nerves, tendons and vessels. Ankle arthroscopy was performed in 5 fresh ankles using 2.7 mm 300 arthroscopy with the same portals as mentioned above. The maximum visible scope were recorded and the distance between the arthroscopy and the posterior nerves, tendons and vessels was also measured.
  
  
  RESULTS
  The medial portal was located 5 - 12 mm (average, 8 mm) above the tip of medial malleolus, and the lateral portal was located 8 - 24 mm (average, 15 mm) above the tip of lateral malleolus. The coaxial portals, which traversed the PTT sheath and passed posterior to the fibular, not only separated the arthroscopy and instrument from the posterior nerves, tendons and vessels by posterior capsule but also enlarged their distance. The medial and lateral malleolus articular gap, the posterior capsule could be viewed by these portals with as much as 1/2 - 2/3 posterior articular surface of talus. Not only the tibiotalar articular gap but also the dynamic movement between the mortise and the talus were clearly observed. Arthroscopic operation could be performed by instrument through the posterolateral portal.
  
  
  CONCLUSIONS
  The posterior coaxial portals via PTT sheath for ankle arthroscopy have such advantages as easy maneuverability, superior safety, clear vision and larger operation field under arthroscopy.
authors.affiliation: Department of Orthopaedics, Nanjing First Hospital, Nanjing Medical University, Nanjing 210006, China. guijianchao@yahoo.com
authors.forename: Jian-chao
authors.initials: JC
authors.lastname: Gui
authors.forename: Feng
authors.initials: F
authors.lastname: Gao
authors.forename: Li-ming
authors.initials: LM
authors.lastname: Wang
authors.forename: Xiang-jie
authors.initials: XJ
authors.lastname: Gu
authors.forename: Hai-qi
authors.initials: HQ
authors.lastname: Shen
authors.forename: Zhong
authors.initials: Z
authors.lastname: Yu
authors.forename: Yan
authors.initials: Y
authors.lastname: Xu
authors.forename: He
authors.initials: H
authors.lastname: Huang
mesh_terms: D000843:Ankle Joint / Q000033:anatomy & histology* / Q000601:surgery; D001182:Arthroscopy / Q000379:methods*; D006801:Humans