title: [A new kind of minimally invasived external fixator for orthopaedics fabricated with quick casting method].
abstract: OBJECTIVE
  A new kind of external fixator for orthopaedics is designed in order to overcome the shortcomings of high weight, hard to operate and high degree of hurt for the conventional external fixator.
  
  
  METHODS
  The quick casting method is used to realize fast shaping, and FEM (Finite Element Method) is used to verify the practicability of the design.
  
  
  RESULTS
  In order to verify the correctness of the design, FEM is used to simulate it. It is concluded from the simulated result that the biggest relative displacement between the borders of the separated bones is just 0.37 mm, which is much less than the requested value 1 mm. This fits the request to cure the patients whose bones are broken and shows the correctness of the design. Finally, ten sheep are used as specimen to verify the feasibility of the design. It is concluded from the X ray sketches of 2 weeks, 4 weeks and 8 weeks that there is no relative displacement happened between the border of the broken bone and the bone is well cured.
  
  
  CONCLUSIONS
  This kind of device is feasible to cure the broken bones and the design scheme can be used as the final treatment means.
authors.affiliation: Orthopeadic Hospital of PLA, Beijing 100853.
authors.forename: Xangdang
authors.initials: X
authors.lastname: Liang
authors.forename: Geng
authors.initials: G
authors.lastname: Sun
authors.forename: Zhanshe
authors.initials: Z
authors.lastname: Guo
authors.forename: Yucang
authors.initials: Y
authors.lastname: Ma
authors.forename: Yuanyong
authors.initials: Y
authors.lastname: Fang
mesh_terms: D000818:Animals; D004867:Equipment Design; D016267:External Fixators; D005592:Fracture Fixation / Q000295:instrumentation*; D012756:Sheep