Management of Large Focal Chondral and Osteochondral Defects in the Knee

Abstract

Large, focal articular cartilage defects of the knee (> 4 cm2) can be a source of significant morbidity and often require surgical intervention. Patient- and lesion-specific factors must be identified when evaluating a patient with an articular cartilage defect. In the management of large cartilage defects, the two classically utilized cartilage restoration procedures are osteochondral allograft (OCA) transplantation and cell therapy, or autologous chondrocyte implantation (ACI). Alternative techniques that are available or currently in clinical trials include a hyaluronan-based scaffold plus bone marrow aspirate concentrate, a third-generation autologous chondrocyte implant, and an aragonite-based scaffold. In this review, we will focus on OCA and ACI as the mainstay in management of large chondral and osteochondral defects of the knee. We will discuss the techniques and associated clinical outcomes for each, while including a brief mention of alternative treatments. Overall, cartilage restoration techniques have yielded favorable clinical outcomes and can be successfully employed to treat these challenging large focal lesions.

Elemental and Configural Associative Learning in Spatial Tasks: Could Zebrafish be Used to Advance Our Knowledge?

“…For example, as mentioned above, certain structures in the zebrafish brain have been found homologous to mammalian counterparts. From the perspective of spatial learning, one of the most important of these is the lateral pallium, which has been argued to be the zebrafish homolog of the mammalian hippocampus (Butler, 2000;López et al, 2000b;Mueller and Wullimann, 2009;Vargas et al, 2009; also see review by Gerlai, 2017a). Functionally, this structure has also been found similar between fish and mammals, as its lesioning, for example, leads to spatial learning deficits in both these taxa (reviewed by Rodríguez et al, 2002).…”

Hydrogel-based autologous chondrocyte implantation leads to subjective improvement levels comparable to scaffold based autologous chondrocyte implantation

“…1 3 was introduced clinically in 1994 by Brittberg et al. [4], this technique has been established and according to different studies, it is by now the preferred therapy especially for fullthickness focal cartilage defects over 2.5 cm 2 of the knee [5,7,11].…”

From Single Batch to Mass Production–Automated Platform Design Concept for a Phase II Clinical Trial Tissue Engineered Cartilage Product

“…Furthermore, especially in younger patients (<60 years) the risk of revision surgery, associated with lower treatment efficacy, is increased by 20-35% in total (5,6). Current treatments for focal cartilage defects, e.g., microfracturing or autologous articular chondrocyte implantation, are often associated with drawbacks such as limited defect sizes and donor site morbidity (7)(8)(9). Various new treatment approaches using ATMPs are currently under scientific investigation, also in clinical trials with mainly somatic cell therapy medicinal products (sCTMP) among others (10,11).…”