The Contrastive Study On The Bone Quality Of Rheumatoid Arthritis And Osteoarthritis

Objective Rheumatoid arthritis and osteoarthritis are two kinds of frequently-occurring osteoarthropathy which can cripple the patients. Total knee replacement is the prevalent therapeutic method for these diseases now. Bone quality is a new concept to evaluate the strength of human bone. It is one of the factors which determine the lifetime of artificial knee joint. Comparing the bone quality of rheumatoid-arthritis with the bone quality of osteoarthritis can instruct the clinical treatment.Methods The samples of the spongy bone of the patients with rheumatoid arthritis and the spongy bone of the patients with osteoarthritis were collected.The bone histomorphometrics of these samples was analyzed and the area of the trabecular (BS/BV%), trabecular thickness (Tb.Th) and trabecular node number (Tb.n) were calculated. Scanning and transmission electron microscope were used to observe the bone micro-structure of the samples. The ratio of minerals to bone matrixes was calculated by calcining the bone samples. Results There was a significant difference between BV/TV%, Tb.Th and Tb.n of rheumatoid arthritis and osteoarthritis (P<0.01).In RA group, it showed extensive resorption of the trabecula horizontally and vertically, manifested as thinning,and breaking of the trabecula, which resulted in widening the intertrabecula space. The collagen fibrils on trabecula surface were scrappy, thinner and breaking. In OA group, the trabecula surface was glassy. The micro-structure of network was intact. There were many functional osteoclasts in the RA samples. It was difficult to find the osteoclasts in the OA samples. The osteoblasts were found easily. In OA group,the ratio of minerals to bone matrixes is subnormal.Conclusion The bone quality which includes sundry parameters of the patients with osteoarthritis is superior to the patients’with rheumatoid arthritis. What caused the badly bone quality may be the functional osteoclasts.In OA group, The subnormal ratio of minerals to bone matrixes indicates the trabeculae were mineralized insufficiently. In order to know how the bone quality affects the life of the artifical joint, it is necessary to take the large sample test.