Subchondral Bone Trabecular Integrity Predicts and Changes Concurrently With Radiographic and Magnetic Resonance Imaging–Determined Knee Osteoarthritis Progression

Abstract

Objective To evaluate subchondral bone trabecular integrity (BTI) from a radiograph as a predictor of knee osteoarthritis (OA) progression. Methods Longitudinal (baseline, 12- and 24-month) knee radiographs were available from 60 female subjects with knee OA. OA progression was defined by 12- and 24-month change in radiographic medial compartment minimal joint space width (JSW) and medial joint space area (JSA), and medial tibial and femoral cartilage volume from magnetic resonance imaging. Bone Trabecular Integrity (BTI) of the medial tibial plateau was analyzed by fractal signature analysis with a commercially available software. Receiver Operating Characteristic curves of BTI were used to predict 5% change in OA progression parameters. Results Individual terms (linear and quadratic) of baseline BTI of vertical trabeculae predicted knee OA progression based on 12- and 24-month change in JSA (p<0.01 for 24 months), 24-month change in tibial (p<0.05) but not femoral cartilage volume, and 24-month change in JSW (p=0.05). ROC utilizing both terms of baseline BTI predicted 5% change in the OA progression parameters over 24 months with high accuracy as reflected by the area under the curve (AUC) measures: JSW 81%, JSA 85%, tibial 75% and femoral 85% cartilage volume. Change in BTI was also significantly associated (p<0.05) with concurrent change in JSA over 12 and 24 months and change in tibial cartilage volume over 24 months. Conclusions BTI predicts structural OA progression as determined by radiographic and MRI outcomes. BTI may therefore be worthy of study as an outcome measure for OA studies and clinical trials.

Osteoarthritis: rationale for a new paradigm shift involving transforming growth factor-β1

“…OA bone's hardness is 7% lower than that of osteoporotic bone, indicating that OA bone has a reduced elastic modulus 29 . These results support the view of a more generalized bone metabolic disease in OA [30][31][32] and that alteration of subchondral bone integrity is a key event in OA 33 .…”

MRI texture analysis of subchondral bone at the tibial plateau

“…Radiographic indices of subchondral bone integrity have previously been associated with increased cartilage thickness[10] and decreased risk of progressive joint space loss [9]. Previous MR studies have demonstrated alterations in microstructural trabecular morphometry measurements between volunteers and individuals with OA [13,14], and that such measurements correlate well with severity of OA [15].…”

“…Therefore, biomarkers of early changes in SB architecture may be helpful in the early detection and monitoring of OA as well as evaluation of treatment response. SB architecture has been evaluated using radiography, employing techniques such as fractal signature analysis [8,9], bone density measurement [10] and trabecular microstructural analysis [11]. Such techniques have had some success in demonstrating associations between changes in SB structure/density with onset and progression of OA.…”

Subchondral bone and osteoarthritis

“…Finally, Kraus et al [31] have shown that bone trabecular integrity assessed by fractal signature on plain knee radiographs could predict structural progression over 24 months as determined by radiographic and MRI outcomes. Altogether, these clinical studies support strong evidence that subchondral bone is a key factor in the onset and the progression of the disease.…”