Tibial cartilage volume measurement in knee osteoarthritis using magnetic resonance imaging

Abstract Background Cartilage degeneration is considered as the initial defect in osteoarthritis. Measurement of cartilage volume is important to monitor disease progression and therapeutic response. Objectives To measure tibial cartilage volume using magnetic resonance imaging (MRI), and to evaluate the accuracy and interobserver reliability of tibial cartilage volume measurement using MRI. Methods The outline boundaries of the medial and lateral tibial cartilage were drawn manually on 1 mm slices using a track-ball to calculate the volume of each slice. Total calculated MRI-derived tibial cartilage volume was determined by summation of the slice volumes. The calculated tibial cartilage volume was compared to the actual tibial cartilage volume. Results There was a strong correlation between the calculated and actual tibial cartilage volumes determined by a radiologist and a researcher (98% and 89% agreement in medial tibial cartilage, 99% and 97% agreement in lateral tibial cartilage, respectively). High observer reliability was identified (92% agreement in medial tibial cartilage and 97% agreement in lateral tibial cartilage). Conclusion Tibial cartilage volume measurement using MRI can be easily performed by well-trained personnel such as radiologists or residents, and can be used to estimate tibial cartilage volume preoperatively in total knee arthroplasty, and to monitor disease progression and response to therapy.