Background: In order to answer clinical therapy-oriented questions, reliable and consistent depiction of articular cartilage across technical platforms is necessary.
Materials and methods: Technical standards and developments in cartilage imaging are summarized based on current literature and experience from clinical daily routine.
Results: Clinical questions that need to be answered relate to cross-sectional extent, depth, differentiating cartilaginous from bony components of a lesion and to the lesion's location within the compartment. If present, displaced fragments, concomitant meniscal, ligamentous and/or degenerative lesions should be identified. To date, magnetic resonance imaging (MRI) is the workhorse of cartilage imaging and is largely based on moderately T2-weighted and also proton-density (PD)-weighted fat-suppressed turbo-spin-echo sequences. Direct MR- and CT-arthrography are the gold standard to evaluate thin cartilage layers. Recent advances in coil and MR sequence design, increased availability of 3T-MR scanners and more and more sophisticated acceleration techniques allow for better spatial resolution and more robust image contrast at acceptable scan times.
Discussion: As abundant as current developments in clinical routine cartilage imaging may be, the radiologist must carefully select the approach best suited to answering the clinical questions.
Keywords: Coils; Computed tomography arthrography; Joint cartilage; Magnetic resonance imaging; Sequences.