Are two- and three-dimensional computed tomographic scan measurements of tibial tubercle-trochlear groove distance equivalent? A comparative study
Document Type
Article
Publication Date
6-1-2023
Abstract
Background Accurate planning for patellar instability correction is important in obtaining good post-operative outcome. The main challenge in the current two-dimensional (2-D) computed tomographic (CT) scans method is the difficulty in choosing reliable bony landmarks. This study aimed to compare the reliabilities between the 2-D and three-dimensional (3-D) methods of measuring tibial tubercle-trochlear groove (TT-TG) distance. We hypothesize that the proposed 3-D method will result in measurements with narrower error margin, providing higher reliability and accuracy. Materials and Methods We traced CT scans of 106 knees with no patellofemoral pathology from 59 subjects from the database system and converted all 2-D images into 3-D models to determine the values for each parameter. We compared the intra-and interobserver reliability of each method using intraclass correlation (ICC) and Bland-Altman method. Results The values of TT-TG measured by 2-D and 3-D methods were 16.1 +/- 4.6 mm and 16.2 +/- 4.2 mm, respectively. The ICC values of both methods were comparable (95% limits of agreement between the same observer: - 3.3 to 3.8 mm versus - 2.4 to 2.7 mm and different observers: - 4.3 to 4.9 mm versus - 3.9 to 2.7 mm), with 3-D method results in narrower limits of agreement. Conclusion TT-TG measurement is reliable using the 2-D method without using advanced radiographic software. The 3-D method of measuring TT-TG provides measurement with narrower variation when compared with the 2-D method. However, both TT-TG distances' measurement methods in the current study were comparable as the variations are not significant.
Keywords
Three-dimensional model, CT scan, Intraclass correlation, Inter- and intraobserver reliability, Patellar instability
Divisions
ortho
Publication Title
Indian Journal of Orthopaedics
Volume
57
Issue
6
Publisher
Springer Nature
Publisher Location
TIERGARTENSTRASSE 17, D-69121 HEIDELBERG, GERMANY