title: Effects of proximal row carpectomy on wrist biomechanics: a cadaveric study.
abstract: BACKGROUND
  Many studies show good clinical results after proximal row carpectomy. Some biomechanical consequences are documented, but to our knowledge muscle moment arm variations have not previously been quantified.
  
  
  METHODS
  In five fresh-frozen wrist, kinematics and tendon excursions were measured using a 3D electrogoniometer and Linear Variable Differential Transformers (SOLARTRON Inc., AMETEK Advanced Measurement Technology, Inc, 801 South Illinois Avenue, Oak Ridge, TN 37831-2011, USA), respectively, in three conditions: intact wrist, after posterior capsulotomy and after proximal row carpectomy. Mean pivot point, defined as the point whose sum of the squared distances to the helical axes is minimum, wrist range of motion and mean moment arms were measured during dorso-palmar flexion, radioulnar deviation and circumduction movements.
  
  
  RESULTS
  No alteration of the range of motion was observed. On the other hand, the mean pivot point shifted proximally (6.8-9.1mm) after proximal row carpectomy (p<0.05) for all motions tested and most muscle moment arms decreased significantly after proximal row carpectomy.
  
  
  CONCLUSIONS
  The results of this study allow a better understanding of the biomechanical effects of this procedure. The important moment arm reduction and pivot point displacement suggest modifications of joint biomechanical parameters which could influence the functional outcome of PRC.
authors.affiliation: Laboratory of Anatomy, Biomechanics and Organogenesis, Pr. M. Rooze, Faculty of Medicine, Université Libre de Bruxelles, Lennik Street 808, 1070 Brussels, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: Sobczak
authors.forename: P
authors.initials: P
authors.lastname: Rotsaert
authors.forename: M
authors.initials: M
authors.lastname: Vancabeke
authors.forename: S
authors.initials: S
authors.lastname: Van Sint Jan
authors.forename: P
authors.initials: P
authors.lastname: Salvia
authors.forename: V
authors.initials: V
authors.lastname: Feipel
mesh_terms: D002102:Cadaver; D002348:Carpal Bones / Q000601:surgery*; D006801:Humans; D018482:Muscle, Skeletal / Q000033:anatomy & histology* / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D012399:Rotation; D014955:Wrist Joint / Q000502:physiology* / Q000601:surgery*