The Clinical Research Of Magnetic Resonance Imaging（MRI）Evaluating The Interventional Therapy Effect Of Adult Avascular Necrosis Of The Femoral Head（ANFH）

Objective: To explore the clinical value of magnetic resonance imaging(MRI)evaluating the interventional treatment effect of adult avascular necrosis of the femoral head(ANFH).Methods: Twenty-five ANFH patients who received the interventional treatment were enrolled from January 2012 to June 2015.A total of 42 hip jionts were included. The age ranged from 19~61 and the averaged age was 44.5±11.2 years. The arterial catheterization point was in contralateral(healthy) side femoral artery in single ANFH, and the brachial artery in bilateral ANFH. The catheter was inserted to the position of the medial femoral circumflex artery, the lateral femoral circumflex artery and the obturator artery arising, respectively. After confirming catheter location, the anticoagulant agents, antispasmodics and vasodilators were injected. All patients were underwent MRI scan before treatment. The follow-up MRI scan were underwent on 4 months, 12 months and 24 months after treatment, respectively. The MRI scan sequence included the coronary and axial T1 WI, T2 WI of fast spin echo(FSE) sequence, short time inversion recovery(STIR). Based on MRI, We analyzed the ARCO stage of ANFH, the extent of bone marrow secondary edema around the necrotic area and the changes of the hip joint effusion volume. The ARCO stage of ANFH, the extent of bone marrow secondary edema around the necrotic area, the changes of the hip joint effusion volume, joint pain grading and joint function were classified, according to time quantum. All the parameters were analyzed by multiple independent samples compare ranks sum test. We used four table data correlation analysis to evaluate the correlation between bone marrow secondary edema around the necrotic area and joint pain and joint function grading. Results: The before treatment MRI showed the ARCO stage of ANFH were: phase I 2 hips, II 19 hips, III 11 hips and IV 10 hips. All forty two hips were underwent two interventional perfusions. The results of before and after treatment MRI imaging were following:(1) To the last follow-up study, we found the secondary edema disappeared in 11 hips, only one enlarged obviously. The extent of bone marrow secondary edema around the ischemia necrotic area in 30 hips were alleviated varying degrees after treatment. But two of them, edema were aggravated and the extent increased significantly 4 months after treatment. One and two year after treatment, we found that the exacerbated edema alleviated.(2) In 40 hips, the avascular necrosis zone were no obvious change. One ischemic necrosis area shrinked slightly and one enlarged. There were no statistical significance(P > 0.05) between the ARCO stage of ANFH.(3) There was no statistical significance(P > 0.05) in articular cavity effusion change after intervention perfusion. Therapeutic evaluation: In this study, 34 hip joints pain disappeared, relieved or alleviated obviously, and joint function improved to varying degree. The clinical total effective rate was about 81%. The analysis result suggested that the relevance between bone marrow edema and pain grading and joint function grading are significant. Comparing different bone marrow edema group we found the heavier degree of bone marrow edema, interventional therapy after edema was reduced significantly, clinical curative effect is significant, improvement of symptoms more obvious. Conclusion:(1) In both pre- and post-interventional treatment, MRI can directly show the changes of extent of secondary bone marrow edema around ANFH.(2) In ANFH patients, the degree of secondary marrow edema has close relation with VAS score and hip joint Harris grading, which can be used as an index of interventional treatment to evaluate after treatment outcome.