Combined use of cartilage thickness and knee alignment better predicts proximal tibial subchondral bone mass than knee alignment alone: preliminary findings

Subchondral bone is an important shock absorber of the joint, together with the overlying cartilage. Semi-quantitative assessments suggest that bone and cartilage morphology are likely to be associated [1]; however, their actual relationships are unclear. Using micro-CT, we revealed significant associations between proximal tibial medial-to-lateral (M:L) subchondral bone volume fraction (BV/TV) ratios and knee alignment [2], a surrogate of joint loading. It can be expected also the cartilage thickness (Cg.Th) to reflect this relationship and, possibly, to improve the prediction of M:L bone mass distribution, over just knee alignment alone.
The aims of this study, in end-stage knee OA, were to (1) explore associations between proximal tibial M:L BV/TV ratio, M:L Cg.Th ratio and knee alignment; (2) determine whether the Cg.Th explained additional M:L variation in the underlying subchondral bone mass, beyond the variation explained by knee alignment.