title: Three-dimensional imaging and templating improve glenoid implant positioning.
abstract: BACKGROUND
  Preoperative quantitative assessment of glenoid bone loss, selection of the glenoid component, and definition of its desired location can be challenging. Placement of the glenoid component in the desired location at the time of surgery is difficult, especially with severe glenoid pathological conditions.
  
  
  METHODS
  Forty-six patients were randomly assigned to three-dimensional computed tomographic preoperative templating with either standard instrumentation or with patient-specific instrumentation and were compared with a nonrandomized group of seventeen patients with two-dimensional imaging and standard instrumentation used as historical controls. All patients had postoperative three-dimensional computed tomographic metal artifact reduction imaging to measure and to compare implant position with the preoperative plan.
  
  
  RESULTS
  Using three-dimensional imaging and templating with or without patient-specific instrumentation, there was a significant improvement achieving the desired implant position within 5° of inclination or 10° of version when compared with two-dimensional imaging and standard instrumentation.
  
  
  CONCLUSIONS
  Three-dimensional assessment of glenoid anatomy and implant templating and the use of these images at the time of surgery improve the surgeon's ability to place the glenoid implant in the desired location.
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Joseph P
authors: JP
authors: Iannotti
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Scott
authors: S
authors: Weiner
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Eric
authors: E
authors: Rodriguez
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Naveen
authors: N
authors: Subhas
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Thomas E
authors: TE
authors: Patterson
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Bong Jae
authors: BJ
authors: Jun
authors: Department of Orthopaedic Surgery, Orthopaedic and Rheumatologic Institute (J.P.I., S.W., E.R., T.E.P., and E.T.R.), Imaging Institute (N.S.), and Department of Biomedical Engineering, Lerner Research Institute (B.J.J.), Cleveland Clinic, 9500 Euclid Avenue, Cleveland, OH 44195. E-mail address for J.P. Iannotti: iannotj@ccf.org.
authors: Eric T
authors: ET
authors: Ricchetti
mesh_terms: D019643:Arthroplasty, Replacement / Q000295:instrumentation / Q000379:methods*; D061165:Glenoid Cavity; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007595:Joint Prosthesis; D010003:Osteoarthritis / Q000000981:diagnostic imaging / Q000601:surgery*; D011300:Preoperative Care / Q000379:methods*; D012785:Shoulder Joint / Q000000981:diagnostic imaging / Q000601:surgery*; D016037:Single-Blind Method; D014057:Tomography, X-Ray Computed / Q000379:methods*; D016896:Treatment Outcome