Femoral External Rotation Measured on CT and MRI

A Prospective Cohort Study to Compare the Accuracy of Femoral External Rotation Measured on CT and MRI

This study aims to compare the femoral external rotation measured on CT and MRI to that measured intraoperatively to clarify the influence of residual cartilage on posterior condyle on the preoperative planning of total knee arthroplasty.

Inclusion Criteria:

1. 50-85 years old
2. patients with osteoarthritis (Kellgren-Lawrence Grade III or IV) underwent total knee arthroplasty.

Exclusion Criteria:

1. patients cannot endure TKA due to severe heart failure, arrhythmia, myocardial infarction, infection or other reason.
2. patients who cannot undergo MRI.