Correlation Between Bone Marrow Edema Of Femoral Head Necrosis And IL-6 Expression In Femoral Head Bone Marrow

Objective: To investigate the correlation between bone marrow edema of femoral head necrosis and the expression of interleukin-6(IL-6)in bone marrow.Methods : From June 2016 to March 2019,we received 32 patients(including 42 hips)with early femoral head necrosis treated with porous core decompression in our department of bone and joint surgery.Preoperative combined medical history and X-ray and MRI aimaging data were staged according to the ARCO classification criteria,including 8 hips in stage I,17 hips in stage II,and 17 hips in stage III.At the same time,according to the signs of nuclear magnetic lipids,these cases were divided into two groups: 6 hips without bone marrow edema and 36 hips with bone marrow edema.Further,according to the range of bone marrow edema in the femoral head,bone marrow edema was divided into 0 to 3: 6 hips in grade 0.(ie no bone marrow edema),9 hips in grade 1,12 hips 2 grade,15 hips 3 grade.All cases were performed medullary core decompression and specimens from sites of femoral head necrosis area were taken,recorded and stored,correspondingly,ELISA assay kit were employed to detect the interleukin-6 expressions of different groups respecting their precategorized techniques.Statistical software spss20.0 was used to analyze the association of IL-6 expression with different ARCO stage and bone marrow edema classification of femoral head necrosis.Results: all 42 hips the incidence of bone marrow edema was 85.71%.The bone marrow edema of femoral head necrosis mainly occurred in ARCO stage II and III.The incidence of bone marrow edema gradually increased in ARCO stage I ? III,and the difference was statistically significant(?2=15.850,P=0.006).Spearman correlation analysis indicated that ARCO stage had positive association with marrow edema and statistical with significance(R=0.567,P<0.05).The bone marrow IL-6 content was higher in the bone marrow edema group(44.49±11.83)pg/ml than in the bone marrow edema group(16.02±3.29)pg/ml,the difference was statistically significant(?2=9.140,P=0.004);bone marrow IL-6 expression in bone marrow edema grade 0(16.02 ± 3.29)pg / ml,grade 1(28.89 ± 6.99)pg / ml,grade 2(44.78 ± 6.81)pg / ml,grade 3(53.62 ± 6.34)pg / ml,There was a statistically significant difference between the groups(F=63.564,P=0.000),the difference in the bone marrow edema between the two groups was statistically significant(P value was below 0.05).The ARCO staging of bone marrow IL-6 in femoral head necrosis: stage I(27.65±14.26)pg/ml,stage II(36.98±14.76)pg/ml,stage III(49.88±8.64)pg/ml,there was a statistically significant difference between the groups(F=9.667,P=0.000);the difference between the two groups was statistically significant(P value was below 0.05);spearman correlation analysis demonstrated that IL-6 had positive associations with different marrow edema grades and ARCO stages,with relatively coefficients of 0.560 and 0.879,respectively(P < 0.05).Conclusion: IL-6 may be involved in the pathogenesis of bone marrow edema in femoral head necrosis,mediating intramedullary inflammatory response,and can be used as an indicator to reflect the extent of bone marrow edema;overexpression of IL-6 in bone marrow edema may reflect the enhancement of necrotic bone resorption in the femoral head,leading to bone metabolism disorder in the femoral head,aggravating the progression of osteonecrosis.