title: A method for quantifying condylar motion in patients with osteoarthritis using an electromagnetic tracking device and computed tomography imaging.
abstract: OBJECTIVE
  The purpose of this study was to develop a method to accurately study the kinematic changes of the temporomandibular joint (TMJ) in patients treated with hemijoint implant reconstruction for dysfunction of advanced degenerative osteoarthritis.
  
  
  METHODS
  Mandibular kinematic motion data and patient-specific computed tomography (CT) data were acquired. Patients were fitted with custom dental stents that were embedded with metal markers to link the mandibular kinematics data with the 3-dimensional TMJ CT images. An electromagnetic tracking device was used to collect kinematic motion data during maximal mouth opening and closing. The coordinate systems of the kinematic data and CT data were registered to calculate the motion of the mandibular condyle.
  
  
  RESULTS
  This technique was successfully used to study patients with motion aberration of the TMJ due to osteoarthritis. A typical case is illustrated in which the motion of both mandibular condyles was simulated preoperatively and postoperatively.
  
  
  CONCLUSIONS
  The results of this study suggest that it is possible to use the proposed methodology to accurately quantify the motion of the mandibular condyle in 3 dimensions. The developed technique is user-friendly and noninvasive to the patient. The proposed methodology is a potential clinical tool that may be used in the management of patients with TMJ dysfunction.
authors.affiliation: Division of Oral and Maxillofacial Surgery, Department of Surgery, Mayo Clinic, Rochester, MN 55905, USA. evre@baltali.org
authors.forename: Evre
authors.initials: E
authors.lastname: Baltali
authors.forename: Kristin D
authors.initials: KD
authors.lastname: Zhao
authors.forename: Matthew F
authors.initials: MF
authors.lastname: Koff
authors.forename: Ercan
authors.initials: E
authors.lastname: Durmuş
authors.forename: Kai-Nan
authors.initials: KN
authors.lastname: An
authors.forename: Eugene E
authors.initials: EE
authors.lastname: Keller
mesh_terms: D055590:Electromagnetic Phenomena / Q000295:instrumentation*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008335:Mandibular Condyle / Q000000981:diagnostic imaging / Q000503:physiopathology*; D009068:Movement; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000503:physiopathology*; D010865:Pilot Projects; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D015607:Stents; D013704:Temporomandibular Joint / Q000000981:diagnostic imaging / Q000503:physiopathology*; D013705:Temporomandibular Joint Disorders / Q000000981:diagnostic imaging / Q000503:physiopathology*; D014057:Tomography, X-Ray Computed