安装大腿近侧气囊止血带对髌股关节运动的影响

目的探讨膝关节屈曲和伸直状态下安装大腿近侧气囊止血带对髌股关节运动的影响。方法收集住院的非髌股关节疾病患者,选择膝关节20侧,在腰麻或连续硬膜外状态下屈膝30°时测量膝关节髌骨高度和股骨滑车角,然后分伸膝位安装止血带和屈膝位安装止血带两组自身先后对比,测量膝关节不同屈曲角度下Laurin髌股关节外侧角和Merchant吻合角。比较气囊止血带在膝关节不同屈伸状态下对髌股关节运动学的影响。结果在膝关节屈曲30°时,髌骨高度的Caton指数为(1.02±0.19),股骨滑车角(138.9±7.4)°。在膝关节屈曲过程中,髌股关节呈现Merchant吻合角增大的趋势,尤其在膝关节屈曲30~45°的时候变化明显,当屈曲角度继续增大时吻合角基本稳定;Lauren髌股关节外侧角保持相对稳定。伸直位和屈曲位安装止血带引起髌股关节Merchant吻合角和Lauren髌股关节外侧角间的差异没有统计学意义。结论在正常膝关节,大腿近侧气囊止血带对髌股轨迹的影响主要表现为最初屈曲的45°内Merchant髌股吻合角的的增大,而Laurin髌股关节外侧较保持相对稳定。伸直位和屈曲位安装大腿近侧气囊止血带对正常膝关节髌股关节运动的改变没有统计学意义。

The effects of pneumatic tourniquet on patellofemoral kinematics

Objective To describe the different kinematic characters of patellofemoral joint with pneumatic tourniquet at extensed and flexed knees. Methods 20 healthy knees of inpatients with consents were enrolled in the research. Caton Index and trochlear angle were recorded at 30° flexion of knees under lumbar aneasthesia with tourniquet free. We set the pneumatic tourniquet at extension knee and extremely flexion knee as contrast groups, and the Laurin angle and merchant congruent angle were recorded at 30° ,45° ,60° ,90° and 120° of knee position. These angles were compared to describe different patellofemoral kinematics. Results At 30° flexion, Caton Index averaged （ 1.02 ±0.19 ） and trochlear angle was （138.9 ±7.4）°. The merchant congruent angle became larger during knee flexing, especially when the knee flexed from 30° to 45°. The Laurin angle presented no significant change in the range of knee flexion. The Merchant congruent angle and Laurin angle of patellofemoral joint showed no significant difference with pneumatic tourniquet secured at neither extensed nor flexed positions. Conclusions For normal knees, the main kinematic effect of pneumatic tourniquet on the patellofemoral joint with different knee flexion is observed as increase of Merchant congruent angle at the initial 45° flexion of knee, while Laurin angle keeps no significant change in the range of motion. The kinematic characters of patellofemoral joint show no significant difference with pneumatic tourniquet secured at meither extensed nor flexed positions.