title: A nondestructive method to verify the glenosphere-baseplate assembly in reverse shoulder arthroplasty.
abstract: BACKGROUND
  Glenoid dissociation is a rare postoperative complication in reverse shoulder arthroplasty that has severe consequences for the patient and requires revision in most cases. A mechanically compromised Morse taper is hypothesized to be the main cause of this complication, with bony impingements and soft tissue interpositioning being cited as the most important problems. Intraoperative assessment of the taper assembly is challenging. Current methods require applying considerable torque to the glenosphere or relying on radiographs.
  
  
  METHODS
  This in vitro study demonstrates how the assembly quality can be accurately determined in a nondestructive way by exploiting the implant-specific relation between screw and Morse taper characteristics by measuring the angular rotation-torque curve.
  
  
  RESULTS
  The feasibility of the method is demonstrated on 2 reverse implant models. Several data features that can statistically discriminate between optimal and suboptimal assemblies are proposed.
  
  
  CONCLUSIONS
  Suboptimal assemblies can be detected using the method presented, which could easily be integrated in the current surgical workflow. Clinical recommendations based on the method's rationale are also presented, allowing detection of the most severe defect cases with surgical instruments currently in use.
authors.affiliation: Biomechanics Division, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium. Electronic address: steven.leuridan@kuleuven.be.
authors.forename: Steven
authors.initials: S
authors.lastname: Leuridan
authors.affiliation: Health Engineering Technology, Campus Groep T, KU Leuven, Leuven, Belgium.
authors.forename: Quentin
authors.initials: Q
authors.lastname: Goossens
authors.affiliation: Health Engineering Technology, Campus Groep T, KU Leuven, Leuven, Belgium.
authors.forename: Leonard
authors.initials: L
authors.lastname: Pastrav
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Gent, Belgium.
authors.forename: Alexander
authors.initials: A
authors.lastname: Van Tongel
authors.affiliation: Department of Orthopedic Surgery and Traumatology, Ghent University Hospital, Gent, Belgium.
authors.forename: Lieven
authors.initials: L
authors.lastname: De Wilde
authors.affiliation: Department of Orthopedic Surgery, Leuven University Hospitals, Pellenberg, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Debeer
authors.affiliation: Health Engineering Technology, Campus Groep T, KU Leuven, Leuven, Belgium.
authors.forename: Kathleen
authors.initials: K
authors.lastname: Denis
authors.affiliation: Production Engineering, Machine Design and Automation Division, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
authors.forename: Wim
authors.initials: W
authors.lastname: Desmet
authors.affiliation: Biomechanics Division, Department of Mechanical Engineering, KU Leuven, Leuven, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Vander Sloten
mesh_terms: D019643:Arthroplasty, Replacement / Q000009:adverse effects / Q000379:methods*; D006801:Humans; D011474:Prosthesis Design; D012785:Shoulder Joint / Q000601:surgery*; D000072227:Shoulder Prosthesis / Q000009:adverse effects
keywords: Morse taper; Reverse shoulder arthroplasty; glenoid dissociation; glenosphere–baseplate assembly verification; nondestructive; smart surgical instruments