Medial condyle trochlear offset

Last revised by Joachim Feger on 30 Sep 2022

Medial condyle trochlear offset (MCTO) is a measurement to assess the height of the medial trochlear facet with respect to the trochlear groove 1.

Medial condyle trochlear offset has been described for the assessment of trochlear dysplasia in skeletally immature patients 1. It measures and/or quantifies a flat or hypoplastic medial facet, described in type B-D of the Dejour classification 2, as a risk factor for patellofemoral instability 1.

The distance between the most anterior point of the medial trochlear facet and a tangential line through the trochlear groove parallel to the posterior bony contours of the femoral condyles is measured 1. In severely hypoplastic medial facets the measurement can yield a negative value 1. The measurement is conducted on the most superior/proximal axial image showing complete cartilage coverage of the trochlea 1.

A cut-off value of ≤1 mm was found to be highly specific and fairly sensitive for patellofemoral instability, with a reported sensitivity and specificity of 75% and 93% in that study 1.

Medial condyle trochlear offset was described by M. Stepanovich in 2016 as a measurement for skeletally immature patients 1.

ADVERTISEMENT: Supporters see fewer/no ads