Bone-on-bone is a term used when joint and meniscus cartilage of the tibiofemoral joint are worn down so much that - instead of nice shiny opposing joint surfaces - exposed bone is grating on exposed bone.

bone-on-bone thinning
On the one side the normal X-ray 'gap' has gone and bone is touching bone. The normal 'gap' is filled with joint cartilage and meniscus, but on this one side that has worn away.

Common joint surface problems in the knee

A quick overview of the problems one sees in the white joint cartilage at the end of the bones in the knee joint.



Diffuse Tibiofemoral Cartilage Change Prior to the Development of Accelerated Knee Osteoarthritis: Data from the Osteoarthritis Initiative. Harkey MS, Davis JE, BS, Lu B, Price LL, Eaton CB, Lo GH, Barbe MF, Ward R, Zhang M, Liu S-H, Lapane KL and MacKay JW, MRCP,FRCR,13 Timothy E. McAlindon, MD,MPH,1 and Jeffrey B. Driban, PhD1 Clin Anat. 2019 Apr; 32(3): 369–378.

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