Regional analysis of femorotibial cartilage loss in a subsample from the Osteoarthritis Initiative progression subcohort

Abstract

Objective The Osteoarthritis Initiative (OAI) is aimed at validating (imaging) biomarkers for monitoring progression of knee OA. Here we analyze regional femorotibial cartilage thickness changes over one year using 3 Tesla MRI. Specifically, we tested whether changes in central subregions exceed those in the total cartilage plates. Methods The right knees of a subsample of the OAI progression subcohort (n=156 age 60.9±9.9 y) were studied. 54 participants had definite radiographic OA (KLG 2 or 3) and a BMI>30. Mean and minimal cartilage thickness was determined in subregions of the medial/lateral tibia (MT/LT), and of the medial/lateral weight-bearing femoral condyle (cMF/cLF), after paired (baseline, follow-up) segmentation of coronal FLASHwe images with blinding to the order of acquisition. Results The central aspect of cMF displayed a 5.8%/2.8% change in mean thickness in the group of 54/156 participants, respectively, with a standardized response mean (SRM) of -0.47/-0.31, whereas cartilage loss in the total cMF was 4.1%/1.9% (SRM -0.49/-0.30). In the central MT, the rate of change was -1.6% /-0.9% and the SRM -0.29/-0.20, whereas for the entire MT the rate was -1.0%/-0.5% and the SRM -0.21/-0.12. Minimal thickness displayed greater rates of change, but lower SRMs than mean thickness. Conclusions This study shows that the rate of cartilage loss is greater in central subregions than in entire femorotibial cartilage plates. The sensitivity to change in central subregions was higher than for the total cartilage plate in the medial tibia and was similar to the total plate in the medial weight-bearing femur.

The Chondroprotective Role of Erythromycin in a Murine Joint Destruction Model

“…We also observed more femoral cartilage damage in the outer region than the inner zones. These are also consistent with the magnetic resonance imaging analysis of human OA cartilage, 38,39 supporting the validity of this animal model. Such topographical differences could result from differential mechanical stress and the different proteoglycan synthesis of the chondrocytes in these regions.…”

“…Another feature of human joint destruction in OA is the regional differences of cartilage loss within the joint. 38,39 Yet, this feature was rarely discussed in reported studies using animal OA models.…”

“…25,36,37 Ten days after MIA injection, knee joints were evaluated by histological analysis. As different regions of the joint may be differentially affected in human OA, 38,39 we divided the medial half of the knee joint into 3 zones along the medial-lateral axis (Fig. 1A).…”

Intraarticular Sprifermin (Recombinant Human Fibroblast Growth Factor 18) in Knee Osteoarthritis: A Randomized, Double‐Blind, Placebo‐Controlled Trial

“…The primary efficacy end point was the longitudinal change from baseline in central medial femorotibial compartment cartilage thickness at 6 months and 12 months, as assessed using quantitative MRI (qMRI). This end point was chosen since it has been shown to be the most sensitive to change (highest ratio of the mean change divided by the SD of change across participants) (24)(25)(26) The primary safety end points were local and systemic treatment-emergent adverse events (AEs), acute inflammatory reactions, laboratory findings (blood chemistry, hematology, urinalysis), vital signs, and electrocardiographic results (Supplementary Table 1). Treatment-emergent AEs were defined as any AEs with start dates on or after the date of the first injection of study medication and up to 30 days after the last injection, or AEs classified as possibly or probably related to study medication, with start dates on or after the date of the first injection of study medication and up to 30 days after the trial termination visit.…”

Use magnetic resonance imaging to assess articular cartilage

“…In patients with radiographic knee OA, over 12 months, the mean cartilage thickness reduction in the central subregion of medial femoral condyle is 12 µm in knees without pain, 27 µm in those with infrequent pain and 54 µm in those with frequent pain [Eckstein et al 2011]. In a subsample of the OA Initiative progression subcohort, the mean cartilage thickness reduces by 2.8% in the central aspect of medial femoral condyle, 1.9% in the total medial femoral condyle, 0.9% in the central medial tibia and 0.5% for the entire medial tibia [Wirth et al 2009]. In patients with radiographic knee OA, the total tibiofemoral cartilage thickness reduces by 0.8-1.3% in the first year and by 0.7-0.8% in the second year [Wirth et al 2011].…”