Risk Factors for Medial Meniscus Posterior Root Tear,内侧半月板后角损伤多因素分析Byoung-Yoon Hwang, Sung-Jae Kim, Sang-Won Lee, David J. Hunter and Kwang-AmAm J Sports Med 2012 40: 1606 published online May 11, 2012,history review,内侧半月板后角（Medial Meniscus Posterior Root，MMPR）位于膝关节后内间隙，常规膝关节镜入路难于全面观察到。,冯华，洪雷，等.中华骨科杂志，2005,25（11）：651-655. Baldwin JL. Am J Sports Med ,1995,37(12):2355-2360.,Function of MMPR,MMPR与ACL之间存在生物力学相关性,共同限制胫骨的前移传递能量缓冲,Bin SI,Shin SJ. Radial tears of the posterior horn of the medial meniscus.Arthroscopy.2004;20:373-378. Utzschneider S,Weber P,et al.Knee Surg Sports Traumatol Arthrosc.2011;19(10):1643-1648.,Characteristic of MMPR,症状隐匿,没有特异的体征,即使进行关节镜检查也常由于其位置隐蔽,难以接近而漏诊。,轻度屈膝外翻位检查MMPR,Normal or abnormal?,anatomy of MMPR,膝关节MMPR与滑膜的结合部被称为Ramp区域。,Strobel MJ.Ramp Lesions.Berlin Herdelberg:Springer-Verlag,1998,171-178.,anatomy of MMPR,MMPR的滑膜边缘撕裂又称Ramp损伤，是其中较为特异的一种，多见于陈旧性的、病程较长的ACL损伤。,Typical ramp lesion,Classification of ramp lesion,Ramp损伤常被忽视,有些Ramp损伤即使被发现! 也由于无法采用常规的半月板修补缝合方法而被放弃治疗!容易形成“医源技术性忽略”。,characteristics of ramp lesion,继续向前方延伸, 形成更大的内侧半月板桶柄样撕裂,造成整个内侧半月板的撕裂形成半月板后角的复合性撕裂,造成整个后角的不稳定,不会自然愈合,Bhattacharyya T, et al. J Bone Joint Surg Am. 2003;85:4-9 Baratz ME, Fu FH. Meniscal tears: the effect of meniscectomy and of repair on intraarticular contact areas and stress in the human knee: a preliminary report. Am J Sports Med. 1986;14:270-275.,The forgotten corners,Among Asian people,Background: Medial meniscus posterior root tears (MMPRT) have a different clinical effect from other types of meniscal tears.may be related to the frequent use of postures such as the lotus position or squatting ?,Purpose,The present study was designed to identify the risk factors for MMPRT among an Asian sample.Cohort study,Methods,An observational study was performed of 476 consecutive patients undergoing an arthroscopic procedure on their medial meniscus from January 2010 to December 2010. excluding those with ligament laxity, lateral meniscal tear, systemic arthritis, osteonecrosis,or other combined ligament injury. 564-476 Unfollow-up 16%,assessed the relation of these risk factors to the type of meniscal tear(group 1 or 2).,One hundred four patients had MMPRT (group 1)the other patients had other types of medial meniscal tears (group 2).,Demographic characteristics,Demographic characteristics (age, sex, body mass index BMI), radiographic features (mechanical axis angle, tibia vara angle, tibial slope angle, and environmental factors (occupation, trauma history, sports activity level, variables that are representative of the orientallifestyle of lotus position and squatting) were surveyed.,Results,In group 1, there were 7 male and 97 female patients, with an average age of 58.2 years (range, 39-78 years) and BMI of 26.73.4 kg/m2 In group 2, there were 136 male and 236 female patients(P.01 compared with group 1) with an average age of 54.3 years (range, 17-77 years;P.01) and a BMI of 24.9 3.1 kg/m2,Results,With regard to radiographic features, the mechanical axis angle demonstrated a significantly increased varus alignment in group 1 compared with group 2 (P.01 ),Results,Environmental factors showed no differences in occupation, except sports activity level. There were 41 patients (42.7%) in group 1 and 77 patients (20.6%) in group 2 who did not participate in any recreational activity (P.01 ),Multiple logistic regression analysis,Multiple logistic regression analysis,female sex was associated with a 5.9-fold increase in risk mechanical axis angle with a 3.3-fold increase BMI more than 30 kg/m2 with a 4.9-fold increaselower sports activity level with a 2.7-fold increase,Conclusion,Persons with MMPRT had significantly increased age, female sex predominance, higher BMI, greater varus mechanical axis angle, and lower sports activity level compared with persons with other types of meniscal tear. After adjusting for other factors, sex, BMI, mechanical axis angle, and lower sports activity level remained strong determinants of MMPRT.,Conclusion,Interestingly, oriental postural positions including the lotus position and squatting showed no contribution to increased risk of MMPRT. This suggests that intrinsic risk factors (similar to those that predispose to osteoarthritis) predispose to MMPRT.,My experience,1、MMPR-Ramp损伤症状隐匿，特异性体征少，尤其对于ACL陈旧性损伤患者术前MR检查，矢状位可以观察到内侧半月板后角与滑膜交界区高信号,2、对于所有ACL损伤病例关节镜检查时应常规采用经髁间窝或后内侧入路观察内侧半月板后角3、一旦发现Ramp损伤，应积极进行all-inside缝合手术治疗 4、此文献随访人数之多，时间短,请各位老师和同学批评指正！,Thanks for your attention,