Diagnostic Accuracy of MRI in Diagnosing Plantar Plate Tear About Metatarsalgia: Incidental Finding of A Tear on Routine Magnetic Resonance Imaging

CATEGORY: Lesser Toes; Midfoot/Forefoot INTRODUCTION/PURPOSE: This study aimed to assess the rate of plantar plate tear finding on MRI study of symptomatic versus asymptomatic patients. We secondarily aimed to determine the correlation between PP tear grading and symptoms and to assess the diagnostic accuracy of MRI. METHODS: Based on the physical examination report, patients were divided into Symptomatic and Asymptomatic groups. Data from the MRI reports were extracted for the second to fifth plantar plates. All MRIs were studied again by a musculoskeletal radiologist to measure the inter-rater agreement and MRI reports' reliability. MRI finding of the plantar plates was categorized as torn vs. intact. We used the anatomical grading system (AGS) to assess the plantar plate tear grading correlation with symptoms RESULTS: There was an excellent inter-rater agreement (Kappa=0.92). Calculating the odds ratio reveals that the odds of finding intact PP in a symptomatic patient is 16 times more than finding a tear in the same patient. Diagnostic accuracy of MRI shows that PP tear finding on MRI is highly specific and has a low sensitivity meaning that the chance of incidental finding of a PP tear is extremely low. CONCLUSION: MRI is specific for diagnosing plantar plate tear and is suggested to confirm the diagnosis and plan for the surgery when the diagnosis is highly probable concerning the clinical examination.