• Interobserver and intraobserver reliability and validity of the Vancouver classification system of periprosthetic femoral fractures after hip arthroplasty.

      Naqvi, Gohar A; Baig, Shakoor A; Awan, Nasir; Department of Trauma and Orthopaedics, Our Lady of Lourdes Hospital, Drogheda, Co., Louth, Republic of Ireland. (2012-06)
      The Vancouver classification system of periprosthetic fractures has been revalidated in this study, using the radiographs of 45 patients. Three consultants and 3 trainees reviewed the radiographs independently, on 2 separate occasions, at least 2 weeks apart. Interobserver and intraobserver agreement and validity were analyzed, using weighted κ statistics. The mean κ value for interobserver agreement was found to be 0.69 (0.63-0.72) for consultants and 0.61 (0.56-0.65) for the trainees, both representing substantial agreement. Intraobserver κ values ranged from 0.74 to 0.90, showing substantial agreement. Validity analysis of 37 type B cases revealed 81% agreement within B1, B2, and B3 subgroups with a κ value of 0.68 (substantial agreement). This study has reconfirmed the reliability and validity of the Vancouver classification while it also emphasizes the intraoperative assessment of implant stability.