前十字韧带撕裂后胫骨前移现象与膝关节骨性特征的相关性研究

Relationship between anterior tibial translation and bony morphology around the knee after anterior cruciate ligament injury

目的探讨前十字韧带(anterior cruciate ligament,ACL)撕裂后的胫骨前移现象与膝关节骨性解剖特征的相关性。方法回顾性分析2019年9月至2021年8月诊断为急性ACL撕裂且无半月板损伤的67例患者资料,男33例、女34例,年龄(31.7±9.7)岁(范围15~47岁)。于术前矢状面MRI测量外侧间室的胫骨前移、股骨外髁长度和高度、胫骨外侧平台长度、胫骨平台后倾角,计算外髁长高比(股骨外髁长度/股骨外髁高度)、外髁平台伸膝比(股骨外髁长度/胫骨外侧平台长度)、外髁平台屈膝比(股骨外髁高度/胫骨外侧平台长度);依据冠状面MRI信号将前外侧韧带分为完全损伤44例、部分损伤19例、完整4例。比较前外侧韧带完全损伤组与前外侧韧带部分损伤或完整组胫骨前移的差异,采用Pearson相关分析前外侧韧带完全损伤组与部分损伤或完整组胫骨前移与骨性解剖参数的相关性。结果受伤至MR检查的时间为(26.0±22.0)d(95%CI:20.7,31.4 d)。胫骨前移为(5.6±4.0)mm(范围-4.9~16.2 mm),股骨外髁长度(37.3±2.5)mm(范围30.5~43.2 mm),股骨外髁高度(37.4±3.6)mm(范围30.6~46.3 mm),胫骨外侧平台长度(46.9±4.1)mm(范围39.0~56.8 mm),胫骨平台后倾角6.3°±3.1°(范围-3.7°~11.6°),外髁长高比100.4%±8.1%(范围84.1%~119.0%),外髁平台伸膝比80.0%±5.8%(范围66.1%~96.3%),外髁平台屈膝比80.0%±6.0%(范围66.4%~93.8%)。前外侧韧带完全损伤组胫骨前移(6.4±4.3)mm,大于部分损伤或完整组的(3.9±2.8)mm(t=2.52,P=0.014)。在全部患者中,胫骨前移与股骨外髁高度(r=-0.43,P<0.001)、胫骨外侧平台长度(r=-0.350,P=0.004)呈负相关,与外髁长高比(r=0.48,P<0.001)、外髁平台伸膝比(r=0.36,P=0.003)、胫骨平台后倾角(r=0.29,P=0.018)呈正相关。胫骨前移与骨性解剖参数在前外侧韧带完全损伤组表现出与总体相似的相关性(P<0.05),而在前外侧韧带部分损伤或完整组未表现出相关性(P>0.05)。结论股骨远端和胫骨近端的矢状面解剖形态与ACL撕裂后的胫骨前移现象相关,且相关性在前外侧韧带完全损伤时更为显著。

Objective To investigate the relationship between anterior tibial translation(ATT)and bony morphology around the knee after anterior cruciate ligament(ACL)injury.Methods A total of 67 patients diagnosed with acute ACL injury without any meniscal lesions were enrolled in this study between September 2019 and August 2020.Preoperative magnetic resonance imaging(MRI)scans were used to measure the ATT of the lateral compartment,and bony morphology was assessed by measuring lateral femoral condyle(LFC)length,LFC height,lateral tibial plateau(LTP)length,LTP slope and by calculating the following ratios:LFC ratio(LFC length/LFC height),knee extension ratio(LFC length/LTP length),and knee flexion ratio(LFC height/LTP length).The status of the anterolateral ligament(ALL)was assessed by preoperative MRI scans and classified as completely injured(44 patients),partially injured(19 patients),or intact(4 patients).The ATT was compared between patients with completely injured ALL and those with partially injured or intact ALL.Pearson correlation analysis between the ATT and each bony variable was performed in ALL-completely-injured patients and ALL-partially-injured or intact patients.Results Of the 67 patients,33 were male and 34 were female,with a mean of age 31.7±9.7 years(range 15-47 years).The average of time interval between ACL injury and MRI examination was 26.0±22.0 days(95%CI:20.7,31.4 d).The ATT of the lateral compartment was 5.6±4.0 mm(range,-4.9-16.2 mm),the average of LFC length was 37.3±2.5 mm(range,30.5-43.2 mm),the average of LFC height was 37.4±3.6 mm(range,30.6-46.3 mm),the average of LTP length was 46.9±4.1 mm(range,39.0-56.8 mm),the average of LTP slope was 6.3°±3.1°(range,-3.7°-11.6°),LFC ratio was 100.4%±8.1%(range,84.1%-119.0%),knee extension ratio was 80.0%±5.8%(range,66.1%-96.3%),and knee flexion ratio was 80.0%±6.0%(range,66.4%-93.8%).The ATT was greater in patients with completely injured ALL than in patients with partially injured or intact ALL(6.4±4.3 mm vs.3.9±2.8 mm,t=2.52,P=0.014).The ATT was negatively correlated with LFC height(r=-0.43,P<0.001)and LTP length(r=-0.35,P=0.004)and was positively correlated with LFC ratio(r=0.48,P<0.001),knee extension ratio(r=0.36,P=0.003),and LTP slope(r=0.29,P=0.018).All these correlations were still statistically significant in patients with complete ALL injury(P<0.05),but were no significant in patients with partial ALL injury or intact ALL(P>0.05).Conclusion Bony morphology of the distal femur and proximal tibia was associated with ATT after ACL injury.Such an association was more dramatic in patients with a complete ALL injury.