Sharma, N, Brown, A, Bouras, T, Kuiper, JH, Eldridge, J and Barnett, A (2019) The Oswestry-Bristol Classification. The Bone and Joint Journal, 102-B (1). 102 - 107. ISSN 2049-4408

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AIMS: Trochlear dysplasia is a significant risk factor for patellofemoral instability. The Dejour classification is currently considered the standard for classifying trochlear dysplasia, but numerous studies have reported poor reliability on both plain radiography and MRI. The severity of trochlear dysplasia is important to establish in order to guide surgical management. We have developed an MRI-specific classification system to assess the severity of trochlear dysplasia, the Oswestry-Bristol Classification (OBC). This is a four-part classification system comprising normal, mild, moderate, and severe to represent a normal, shallow, flat, and convex trochlear, respectively. The purpose of this study was to assess the inter- and intraobserver reliability of the OBC and compare it with that of the Dejour classification. METHODS: Four observers (two senior and two junior orthopaedic surgeons) independently assessed 32 CT and axial MRI scans for trochlear dysplasia and classified each according to the OBC and the Dejour classification systems. Assessments were repeated following a four-week interval. The inter- and intraobserver agreement was determined by using Fleiss' generalization of Cohen's kappa statistic and S-statistic nominal and linear weights. RESULTS: The OBC showed fair-to-good interobserver agreement and good-to-excellent intraobserver agreement (mean kappa 0.68). The Dejour classification showed poor interobserver agreement and fair-to-good intraobserver agreement (mean kappa 0.52). CONCLUSION: The OBC can be used to assess the severity of trochlear dysplasia. It can be applied in clinical practice to simplify and standardize surgical decision-making in patients with recurrent patella instability. Cite this article: Bone Joint J 2020;102-B(1):102-107.

Item Type: Article
Additional Information: The final accepted manuscript and all relevant information can be found at;
Uncontrolled Keywords: Dejour classification, Medial patellofemoral ligament reconstruction, Patellofemoral instability, Trochlear dysplasia
Subjects: Q Science > Q Science (General)
R Medicine > R Medicine (General)
R Medicine > RS Pharmacy and materia medica
Divisions: Faculty of Medicine and Health Sciences > School of Pharmacy and Bioengineering
Related URLs:
Depositing User: Symplectic
Date Deposited: 11 Mar 2020 11:52
Last Modified: 31 Dec 2020 01:30

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