To prevent the progression of posttraumatic osteoarthritis, assessment of cartilage composition is critical for effective treatment planning. Posttraumatic changes include proteoglycan (PG) loss and elevated water content. Quantitative dual-energy computed tomography (QDECT) provides a means to diagnose these changes. Here, we determine the potential of QDECT to evaluate tissue quality surrounding cartilage lesions in an equine model, hypothesizing that QDECT allows detection of posttraumatic degeneration by providing quantitative information on PG and water contents based on the partitions of cationic and nonionic agents in a contrast mixture. Posttraumatic osteoarthritic samples were obtained from a cartilage repair study in which full-thickness chondral defects were created surgically in both stifles of seven Shetland ponies. Control samples were collected from three nonoperated ponies. The experimental (n = 14) and control samples (n = 6) were immersed in the contrast agent mixture and the distributions of the agents were determined at various diffusion time points. As a reference, equilibrium moduli, dynamic moduli, and PG content were measured. Significant differences (p < 0.05) in partitions between the experimental and control samples were demonstrated with cationic contrast agent at 30 min, 60 min, and 20 h, and with non-ionic agent at 60 and 120 min. Significant Spearman's rank correlations were obtained at 20 and 24 h (ρ = 0.482–0.693) between the partition of cationic contrast agent, cartilage biomechanical properties, and PG content. QDECT enables evaluation of posttraumatic changes surrounding a lesion and quantification of PG content, thus advancing the diagnostics of the extent and severity of cartilage injuries.@en

5 jaar geleden beschreven wij de opkomst van 3D-printen in de geneeskunde. Het betrof het 3D-printen van anatomische structuren, patiëntspecifieke boorgeleiders, zaagmallen en implantaten en het printen van levende cellen, groeifactoren en biomaterialen (‘bioprinten’). Chirurgen maken steeds vaker gebruik van de mogelijkheden van 3D-printen ter voorbereiding op operaties bij patiënten met een ingewikkelde anatomie. Aan de hand van tastbare 3D-modellen kunnen chirurgen de operatie beter voorbereiden en bespreken met de patiënt. Ook kunnen zij de 3D-modellen gebruiken als hulpmiddel bij de training van jonge chirurgen. Steeds vaker worden permanente titanium implantaten geprint. Bioprinten staat nog in de kinderschoenen en kent nog geen directe klinische toepassingen. Zoals wij 5 jaar geleden al voorspelden, moeten er voor de brede klinische toepassing van gebioprinte producten nog vele hordes genomen worden.@en