title: Radiocapitellar joint contacts after bipolar radial head arthroplasty.
abstract: OBJECTIVE
  The purpose of this study was to determine radiocapitellar contacts before and after radial head replacement, using the bipolar design of Judet.
  
  
  METHODS
  Joint contacts were measured by moulding the joint surfaces of 6 fresh-frozen cadaveric specimens, in various positions of elbow flexion and forearm rotation.
  
  
  RESULTS
  Expressed as function of the radial cup, contact areas averaged 44% in the normal elbow, decreasing with flexion and increasing with supination (P < .05). After prosthetic implantation, contact areas averaged 33% and remained quite similar, irrespective of elbow position. Subluxation of the prosthetic head over the lateral margin of the trochlea was seen systematically with supination.
  
  
  CONCLUSIONS
  Because of intraprosthetic mobility, contact areas were not dependant on elbow position. This adaptability, however, also led to abnormal positioning of the prosthetic radial head with supination, subluxing over the trochlea lateral margin.
authors.affiliation: Department of Orthopaedics and Traumatology, Université libre de Bruxelles, Campus Hospitalo-Facultaire Erasme, Brussels, Belgium.
authors.forename: Fabian
authors.initials: F
authors.lastname: Moungondo
authors.forename: Wissam
authors.initials: W
authors.lastname: El Kazzi
authors.forename: Roger
authors.initials: R
authors.lastname: van Riet
authors.forename: Véronique
authors.initials: V
authors.lastname: Feipel
authors.forename: Marcel
authors.initials: M
authors.lastname: Rooze
authors.forename: Frédéric
authors.initials: F
authors.lastname: Schuind
mesh_terms: D019643:Arthroplasty, Replacement / Q000379:methods*; D001696:Biomechanical Phenomena; D002102:Cadaver; D004551:Elbow Joint / Q000601:surgery*; D006801:Humans; D006811:Humerus / Q000502:physiology / Q000601:surgery*; D007593:Joint Instability / Q000517:prevention & control; D007595:Joint Prosthesis; D011403:Pronation / Q000502:physiology; D011474:Prosthesis Design; D011884:Radius / Q000502:physiology / Q000601:surgery*; D016059:Range of Motion, Articular / Q000502:physiology*; D012680:Sensitivity and Specificity; D013314:Stress, Mechanical; D013484:Supination / Q000502:physiology