title: Is a generic targeting guide useful for glenoid component placement in shoulder arthroplasty?
abstract: BACKGROUND
  This study compared postoperative glenoid component version using traditional instrumentation to a generic glenoid targeting guide during total or reverse total shoulder arthroplasty.
  
  
  METHODS
  Glenoid component version was measured on postoperative radiographs of 184 shoulders (traditional, 109; targeting guide, 75). Demographics, preoperative imaging, and operative technique were identified from medical records. Absolute deviation from neutral version and standard deviations (SDs) were calculated.
  
  
  RESULTS
  Average mean ± SD deviation in component version for the traditional technique group was 10° ± 7° compared with 9° ± 6° for the targeting guide group (P = .37; SD P = .12). No significant difference was noted based on operation, body mass index, preoperative version, or operative indication. For the last 30 shoulders in the targeting group, the absolute mean deviation was 6° compared with 11° in the first 30 of that group (P < .01) and 10° in the entire traditional group (P = .01). The SD in the last 30 shoulders in the targeting group was 5° compared with 7° in the first 30 in that group (P = .04) and 7° in the traditional group (P < .01).
  
  
  CONCLUSIONS
  No significant difference in component accuracy was noted between the 2 techniques. The narrower SD in the targeting group, although not statistically significant, suggests less glenoid placement in the extremes of version. A learning curve was noted with the targeting guide, with significantly improved accuracy in later patients.
authors.affiliation: University of Tennessee-Campbell Clinic Department of Orthopaedic Surgery and Biomedical Engineering, Memphis, TN, USA.
authors.forename: Ryan P
authors.initials: RP
authors.lastname: Mulligan
authors.affiliation: University of Tennessee-Campbell Clinic Department of Orthopaedic Surgery and Biomedical Engineering, Memphis, TN, USA.
authors.forename: Frederick M
authors.initials: FM
authors.lastname: Azar
authors.affiliation: University of Tennessee-Campbell Clinic Department of Orthopaedic Surgery and Biomedical Engineering, Memphis, TN, USA. Electronic address: tthrockmorton@campbellclinic.com.
authors.forename: Thomas W
authors.initials: TW
authors.lastname: Throckmorton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019643:Arthroplasty, Replacement / Q000295:instrumentation* / Q000379:methods; D017760:Bone Malalignment / Q000517:prevention & control; D005260:Female; D006801:Humans; D059032:Learning Curve; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012540:Scapula / Q000000981:diagnostic imaging / Q000601:surgery*; D012785:Shoulder Joint / Q000000981:diagnostic imaging / Q000601:surgery*
keywords: Glenoid; targeting; total shoulder arthroplasty; version