Arthroscopic assessment of lateral to medial patellar maltracking: report of seven cases

Abstract

Lateral to medial maltracking of the patella is a subgroup of patellar maltracking where the patella is laterally subluxed in extension and medially subluxed in flexion. It was first described with kinematic magnetic resonance imaging. This type of maltracking can only be suspected with computed tomography if lateral patellar subluxation in extension is associated with medial facet chondral changes and/or subchondral bone sclerosis. We present seven cases in six patients (two of which were asymptomatic, the others complaining with anterior knee pain) in whom the diagnosis was assessed arthroscopically using an arthroscopic portal proximal to the patellofemoral joint. Tracking must be examined from full extension to 90° of flexion. The identification of lateral patellar subluxation on routine anterolateral portal arthroscopy in extension indicates that superolateral assessment through 90° of flexion is required, especially if medial patellar lacet chondral changes are present. No surgical treatment can be proposed at present.