Study Of The Correlation Between Subchondral Bone Marrow Edema And Pain In Knee Osteoarthritis

Purpose:Under magnetic resonance imaging(MRI) detection to evaluate whether the presence of subchondral bone marrow edema(BME) are associated with the different levels of pain among patients suffering osteoarthritis of the knee.Methods: 142 patients with knee osteoarthritis were divided into three groups based on rating scale of their pain:no pain group of 31 cases;mild pain group of 86 cases;moderate or severe pain group of 25 cases.Contingency table analyses and rank sum tests were used to compare the difference among pain stage of OA and BME score in these groups, while BME was identified from MRI(0 grade,no BME,38 cases;1 grade,small BME,69 cases;2 grade,large BME,35 cases). Results: 29.1%(9/31) of OA patients in no pain group had BME,while in mild pain group the percentage was 82.6%(71/86),and in severe pain group 92%(24/25).Compared any two BME scoring of the three groups were showed there was statistical significance between no pain group and mild pain group(x2=12.613,p<0.001) and so was it between no pain group and severe pain group(x2=14.535,p<0.001), notwithstanding, there was no statistical significance between severe pain group and mild pain group(x2=2.126,p=0.065).The results of rank sum tests for several independent samples were showed significant difference of BME scoring among the three groups(P<0.001).With the advance of pain scale,the mean rank of BME increased gradually(79.12、102.82 and 139.26 respectively).Conclusion : The finding on MRI of subchondral BME was associated with the presence or absence of knee pain.There seemed to be a tendency:the more heavy the pain was,the more large the BME would be.