Table 1.

Descriptions of measurements of ACL and patella

	Definition
ACL angle (°)	The angle between the tangential line of ACL and the line perpendicular to the long axis of the tibia in sagittal plane
D (mm)	The distance between the posterior aspects of lateral femoral condyle and tibial plateau in sagittal plane
Patella shift (mm)	The distance between the eminence of patella and the bottom of femoral trochlea at the level of line of posterior femoral condyles in coronal plane
LPFA (°)	The angle between the line of the femoral trochlea eminences and the tangential lines of the lateral facet of the patella in coronal plane
Patellar tilt (°)	The angle between the line of the posterior femoral condyles and long axis line of patella in coronal plane

ACL, anterior cruciate ligament; D, distance of anterior tibial subluxation; LPFA, lateral patellofemoral angle