Fig. 2

Measurement of the angles on sagittal knee MRI. A The preoperative bony slope of the MTP was defined as a line tangent to the most prominent aspects of the anterior and posterior cortices of the MTP (line m), and the cartilage slope of the MTP was defined as a line tangent to the most prominent aspects of the anterior and posterior cartilage remnants (line l). B The frontal view of the knee MRI, in which the MTP is divided into four parts. C On the medial second quarter of the MTP, the angle between lines m and l is measured. ap: anterior most prominent aspect of the MTP pp: posterior most prominent aspect of the MTP