Evaluation of MRI-Based Measurements for Patellar Dislocation: Reliability and Reproducibility

Area of Science:

• Orthopedics
• Radiology
• Biomedical Engineering

Background:

• Patellar dislocation is a common orthopedic injury.
• Accurate imaging assessment is crucial for diagnosis and management.
• Identifying reliable MRI measurements can improve diagnostic accuracy.

Purpose of the Study:

• To identify the most reliable magnetic resonance imaging (MRI) measurements for diagnosing patellar dislocation.
• To evaluate the diagnostic performance and inter-rater reliability of various MRI parameters.

Main Methods:

• Retrospective analysis of MRI scans from 86 knees (48 controls, 38 with patellar dislocation history).
• Measured parameters included lateral trochlear inclination (LTI), sulcus angle (SA), trochlear depth (TD), tibial tubercle-trochlear groove distance (TT-TG), and patellar tendon-lateral trochlear ridge distance (PT-LTR) and its novel modification (PT-LTR horizontal).
• Inter-rater reliability assessed using intraclass correlation coefficients (ICCs); diagnostic accuracy evaluated using ROC analysis.

Main Results:

• All measured parameters differed significantly between control and patient groups (p < 0.05).
• LTI demonstrated the highest diagnostic performance (AUC = 0.981) with excellent inter-rater agreement (sensitivity 89.5%, specificity 97.9%).
• PT-LTR and PT-LTR horizontal also showed strong diagnostic utility (AUC = 0.896) with good reliability.

Conclusions:

• LTI and PT-LTR (including modified versions) are reliable and reproducible MRI measurements for assessing patellar dislocation.
• These parameters offer high diagnostic performance and may be valuable tools in clinical imaging.
• Further prospective studies are recommended to validate their utility in diverse patient populations.