title: Ankle joint pressure changes in high tibial and distal femoral osteotomies: a cadaver study.
abstract: OBJECTIVE
  To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the pressure characteristics of the ankle joint.
  
  
  METHODS
  Varus and valgus malalignment of the knee was simulated in human cadaver full-length legs. Testing included four measurements: baseline malalignment, 5° and 10° re-aligning osteotomy, and control baseline malalignment. For HTO, testing was rerun with the subtalar joint fixed. In order to represent half body weight, a 300 N force was applied onto the femoral head. Intra-articular sensors captured ankle pressure.
  
  
  RESULTS
  In the absence of restriction of subtalar movement, insignificant migration of the centre of force and changes of maximal pressure were seen at the ankle joint. With restricted subtalar motion, more significant lateralisation of the centre of force were seen with the subtalar joint in varus than in valgus position. Changes in maximum pressure were again not significant.
  
  
  CONCLUSIONS
  The re-alignment of coronal plane knee deformities by HTO and DFO altered ankle pressure characteristics. When the subtalar joint was fixed in the varus position, migration of centre of force after HTO was more significant than when the subtalar joint was fixed in valgus. Cite this article: Bone Joint J 2017;99-B:59-65.
authors.affiliation: Inselspital University of Berne, Freiburgstrasse, CH-3010 Berne, Switzerland.
authors.forename: F
authors.initials: F
authors.lastname: Krause
authors.affiliation: Inselspital University of Berne, Freiburgstrasse, CH-3010 Berne, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Barandun
authors.affiliation: FussInstitut Zurich, Kappelistrasse 7, CH-8002 Zurich, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Klammer
authors.affiliation: AO Research Center, Clavadelerstrasse 8, CH-7270 Davos, Switzerland.
authors.forename: I
authors.initials: I
authors.lastname: Zderic
authors.affiliation: AO Research Center, Clavadelerstrasse 8, CH-7270 Davos, Switzerland.
authors.forename: B
authors.initials: B
authors.lastname: Gueorguiev
authors.affiliation: Inselspital University of Berne, Freiburgstrasse, CH-3010 Berne, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Schmid
mesh_terms: D000368:Aged; D000704:Analysis of Variance; D000843:Ankle Joint / Q000502:physiology*; D017760:Bone Malalignment / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D002102:Cadaver; D005260:Female; D005269:Femur / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D010027:Osteotomy / Q000379:methods*; D011312:Pressure; D011859:Radiography; D013380:Subtalar Joint / Q000601:surgery; D013977:Tibia / Q000000981:diagnostic imaging / Q000601:surgery*
keywords: Ankle pressure changes; Distal femoral osteotomy; High tibial osteotomy