Related Factors Analysis Of Radial Displacement Of Meniscus

Objectives To analyze the correlation between the radial displacement of meniscus and sex,age,MRI score,body mass index,medial and lateral meniscus and compare the incidence of RDM in different groups based on the femorotibial angle(FTA)and the sites of the meniscus(anterior horn,body,posterior horn).Methods 281 knees(562 menisci)were included in this study,which including 136 knees of male and 145 knees of female,the average age of the patient was 45.58 +12.30.MRI image and X-ray image were used to define the dislocation degree of meniscus and the FTA.All cases were divided into 5 groups according to age: ≤30 years,30~40 years,40~50 years,50~60 years old,>60 years.We compared the RDM incidence among different age groups,analysis incidence trend and the different incidence caused by gender among age groups.All knees were grouped by right or left,MRI scale and BMI.The RDM different incidence and correlation between factors were analysized.All cases were divided into three groups according FTA,and the different RDM incidence of each groups were calculated.The RDM incidence based on different part of the meniscus(anterior horn,body,posterior horn)were also calculated.Statistical analyses were performed with SPSS17.0,P<0.05 was considered statistically significant.Results 1 The incidence of RDM in each age group were 8.75%,10.26%,20.63%,30.30%,28.26%(P<0.001).2 The incidence of RDM of male and female in 40-50 group were 12.12% and 26.60%(P=0.026),the incidence of male and female were not statistically significant in the other groups.3 The incidence of RDM in left and right were 21.27% and 21.77%(P=0.885).4 The meniscus MRI grade 0 128 cases,grade I 258 cases,grade II 264 cases,grade Ⅲ 472 cases,the RDM incidence of each groups were 3.90%,10.08%,11.36%,37.92%(P<0.001).5 Divided the samples into two groups according BMI < 24kg/m2 and ≥24kg/m2,the RDM incidence were19.63% and 23.29%,(P=0.815).6 The incidence of RDM was 40.21% in medial and 2.85% in lateral meniscus(P<0.001).7 Take age,gender,medial or lateral,BMI,MRI grade into the logistic model,the main influencing factors were obtained by screening variables: gender(OR: 1.953,95% CI: 1.155~3.301),age(OR: 1.046,95% CI: 1.019~1.075),medial or lateral(OR: 27.353,95% CI: 12.612~59.326),grade Ⅲ of MRI(OR: 5.743,95% CI: 1.818~18.142).8 The incidence of RDM in medial meniscus anterior horn,body,anterior horn and body were 6.41%,21.72%,9.61%(P<0.001),the medial meniscus body have the highest incidence according the chi square segmentation method.The incidence of RDM in lateral meniscus anterior horn,body were 0.71%,2.14%(P=0.286).9 8 patients who suffered from RDM caused by lateral menisci were excluded,and the other 273 cases were divided into 3 groups based on different FTA: FTA<182°,182-184°,>184°,the RDM incidence of medial meniscus in each groups were 57.14%,36.05%,34.48%(P=0.004).FTA<182°have the highest RDM incidence,and the incidence between FTA182 ~ 184 ° and >184 °have no significant difference(P=0.799).Conclusions 1 Female,medial meniscus were prone to RDM,age,meniscus injury were the risk factors of RDM.2 There was no correlation between RDM and BMI.3 There was a higher RDM incidence of the medial meniscus in patient.4 The knee of FTA <182°have a higher RDM incidence of medial meniscus.