Open AccessReliability of the Oswestry-Bristol Classification for trochlear dysplasia
Author(s) -
Christian Konrads,
Christoph Gonser,
Sufian S. Ahmad
Publication year - 2020
Publication title -
bone and joint open
Language(s) - English
Resource type - Journals
ISSN - 2633-1462
DOI - 10.1302/2633-1462.17.bjo-2020-0048.r1
Subject(s) - kappa , grading (engineering) , dysplasia , medicine , cohen's kappa , radiology , classification scheme , statistic , orthodontics , nuclear medicine , computer science , mathematics , pathology , statistics , machine learning , civil engineering , geometry , engineering
Aims The Oswestry-Bristol Classification (OBC) was recently described as an MRI-based classification tool for the femoral trochlear. The authors demonstrated better inter- and intraobserver agreement compared to the Dejour classification. As the OBC could potentially provide a very useful MRI-based grading system for trochlear dysplasia, it was the aim to determine the inter- and intraobserver reliability of the classification system from the perspective of the non-founder.Methods Two orthopaedic surgeons independently assessed 50 MRI scans for trochlear dysplasia and classified each according to the OBC. Both observers repeated the assessments after six weeks. The inter- and intraobserver agreement was determined using Cohen’s kappa statistic and S-statistic nominal and linear weights.Results The OBC with grading into four different trochlear forms showed excellent inter- and intraobserver agreement with a mean kappa of 0.78.Conclusion The OBC is a simple MRI-based classification system with high inter- and intraobserver reliability. It could present a useful tool for grading the severity of trochlear dysplasia in daily practice. Cite this article: Bone Joint Open 2020;1-7:355–358.