title: Functional performance of a total ankle replacement: thorough assessment by combining gait and fluoroscopic analyses.
abstract: BACKGROUND
  A thorough assessment of patients after total ankle replacement during activity of daily living can provide complete evidence of restored function in the overall lower limbs and replaced ankle. This study analyzes how far a possible restoration of physiological mobility in the replaced ankle can also improve the function of the whole locomotor apparatus.
  
  
  METHODS
  Twenty patients implanted with an original three-part ankle prosthesis were analyzed 12 months after surgery during stair climbing and descending. Standard gait analysis and motion tracking of the components by three-dimensional fluoroscopic analysis were performed on the same day using an established protocol and technique, respectively.
  
  
  RESULTS
  Nearly physiological ankle kinematic, kinetic and electromyography patterns were observed in the contralateral side in both motor activities, whereas these patterns were observed only during stair climbing in the operated side. Particularly, the mean ranges of flexion at the replaced ankle were 13° and 17° during stair climbing and descending, respectively. Corresponding 2.1 and 3.1mm antero/posterior meniscal-to-tibial translations were correlated with flexion between the two metal components (p<0.05). In addition, a larger tibiotalar flexion revealed by fluoroscopic analysis resulted in a physiological hip and knee moment.
  
  
  CONCLUSIONS
  The local and global functional performances of these patients were satisfactory, especially during stair climbing. These might be associated to the recovery of physiological kinematics at the replaced ankle, as also shown by the consistent antero/posterior motion of the meniscal bearing, according to the original concepts of this ankle replacement design.
authors.affiliation: Movement Analysis Laboratory, Istituto Ortopedico Rizzoli, Bologna, Italy. francesco.cenni@ior.it
authors.forename: F
authors.initials: F
authors.lastname: Cenni
authors.forename: A
authors.initials: A
authors.lastname: Leardini
authors.forename: M
authors.initials: M
authors.lastname: Pieri
authors.forename: L
authors.initials: L
authors.lastname: Berti
authors.forename: C
authors.initials: C
authors.lastname: Belvedere
authors.forename: M
authors.initials: M
authors.lastname: Romagnoli
authors.forename: S
authors.initials: S
authors.lastname: Giannini
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D000368:Aged; D000843:Ankle Joint / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D058737:Arthroplasty, Replacement, Ankle; D001696:Biomechanical Phenomena; D004576:Electromyography; D005260:Female; D005471:Fluoroscopy; D005684:Gait / Q000502:physiology*; D006615:Hip / Q000503:physiopathology; D006801:Humans; D007717:Knee / Q000503:physiopathology; D007719:Knee Joint / Q000502:physiology / Q000503:physiopathology; D008124:Locomotion / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D011187:Posture / Q000502:physiology; D016059:Range of Motion, Articular / Q000502:physiology; D020127:Recovery of Function / Q000502:physiology*; D016474:Weight-Bearing / Q000502:physiology