Abstract：
Knee laxity increases with medial meniscectomy in anterior cruciate ligament (ACL)-reconstructed knees; however, the biomechanical effect of an additional lateral extra-articular tenodesis (LET) is unknown.
The purpose of this study was to determine the kinematic effect of a LET in knees that underwent combined ACL reconstruction (ACL-R) and partial medial meniscus posterior horn (MMPH) meniscectomy. It was hypothesized that the addition of LET would reduce laxity in the ACL-reconstructed knee.
Controlled laboratory study.
Ten fresh-frozen human cadaveric knees (mean age, 41.5 years) were tested using a robotic system under 3 loads: (1) 89.0 N of anterior tibial (AT) load, (2) 5 N·m of internal rotation (IR) tibial torque, and (3) a simulated pivot shift-a combined valgus of 7 N·m and IR torque of 5 N·m-at 0°, 15°, 30°, 45°, 60°, and 90° of knee flexion. Kinematic data were acquired in 4 states: (1) intact, (2) ACL-R, (3) ACL-R + partial MMPH meniscectomy (MMPH), and (4) ACL-R + partial MMPH meniscectomy + LET (MMPH+LET).
In response to AT loading, there was a significant increase seen in AT translation (ATT) in the MMPH state at all knee flexion angles compared with the ACL-R state, with the highest increase at 90° of knee flexion (mean difference, 3.1 mm) (P < .001). Although there was a significant decrease in ATT at 15° of knee flexion with MMPH+LET (P = .022), no significant differences were found at other knee flexion angles (P > .05). In MMPH with IR torque, a significant increase was observed in IR at all knee flexion angles except 90° compared with the ACL-R state (range, 2.8°-4.9°), and this increase was significantly decreased at all flexion angles with the addition of LET (range, 0.7°-1.6°) (P < .05).
Performing a partial MMPH meniscectomy increased ATT and IR in response to AT and IR loads compared with the isolated ACL-R state in a cadaveric model. However, when the LET procedure was performed after partial MMPH meniscectomy, a significant decrease was seen at all knee flexion angles except 90° in response to IR and torque, and a significant decrease was seen at 15° of knee flexion in response to AT load.
LET may be a useful adjunct procedure after ACL-R with partial MMPH meniscectomy to reduce knee laxity.
The purpose of this study was to determine the kinematic effect of a LET in knees that underwent combined ACL reconstruction (ACL-R) and partial medial meniscus posterior horn (MMPH) meniscectomy. It was hypothesized that the addition of LET would reduce laxity in the ACL-reconstructed knee.
Controlled laboratory study.
Ten fresh-frozen human cadaveric knees (mean age, 41.5 years) were tested using a robotic system under 3 loads: (1) 89.0 N of anterior tibial (AT) load, (2) 5 N·m of internal rotation (IR) tibial torque, and (3) a simulated pivot shift-a combined valgus of 7 N·m and IR torque of 5 N·m-at 0°, 15°, 30°, 45°, 60°, and 90° of knee flexion. Kinematic data were acquired in 4 states: (1) intact, (2) ACL-R, (3) ACL-R + partial MMPH meniscectomy (MMPH), and (4) ACL-R + partial MMPH meniscectomy + LET (MMPH+LET).
In response to AT loading, there was a significant increase seen in AT translation (ATT) in the MMPH state at all knee flexion angles compared with the ACL-R state, with the highest increase at 90° of knee flexion (mean difference, 3.1 mm) (P < .001). Although there was a significant decrease in ATT at 15° of knee flexion with MMPH+LET (P = .022), no significant differences were found at other knee flexion angles (P > .05). In MMPH with IR torque, a significant increase was observed in IR at all knee flexion angles except 90° compared with the ACL-R state (range, 2.8°-4.9°), and this increase was significantly decreased at all flexion angles with the addition of LET (range, 0.7°-1.6°) (P < .05).
Performing a partial MMPH meniscectomy increased ATT and IR in response to AT and IR loads compared with the isolated ACL-R state in a cadaveric model. However, when the LET procedure was performed after partial MMPH meniscectomy, a significant decrease was seen at all knee flexion angles except 90° in response to IR and torque, and a significant decrease was seen at 15° of knee flexion in response to AT load.
LET may be a useful adjunct procedure after ACL-R with partial MMPH meniscectomy to reduce knee laxity.
摘要：
■前交叉韧带（ACL）重建膝盖的内侧半月板切除术会增加膝盖松弛；但是，额外的外侧关节外肌腱固定术(LET)的生物力学效果尚不清楚.
■本研究的目的是确定接受ACL重建（ACL-R）和部分内侧半月板后角（MMPH）半月板切除术的膝关节LET的运动学效果。假设添加LET将减少ACL重建的膝盖的松弛。
■对照实验室研究。
■十个新鲜冷冻的人类尸体膝盖（平均年龄，41.5年）在3种载荷下使用机器人系统进行了测试：（1）胫骨前（AT）载荷的89.0N，（2）5N·m的内旋（IR）胫骨扭矩，和（3）模拟的枢轴移位-在0°时7N·m的组合外翻和5N·m的IR扭矩，15°,30°,45°,60°,膝关节弯曲90°。在4种状态下获取了运动学数据：（1）完整，(2)ACL-R,（3）ACL-R+部分MMPH半月板切除术（MMPH），和(4)ACL-R+部分MMPH半月板切除术+LET(MMPH+LET)。
■响应AT加载，与ACL-R状态相比，在所有膝关节屈曲角度下，MMPH状态下的AT平移（ATT）均显着增加，膝关节屈曲90°时增加最大(平均差，3.1mm)(P<.001)。尽管使用MMPHLET在膝关节屈曲15°时ATT显着降低（P=0.022），其他膝关节屈曲角度差异无统计学意义(P>.05)。在具有IR扭矩的MMPH中，与ACL-R状态相比，除90°外，所有膝关节屈曲角度的IR均显着增加（范围，2.8°-4.9°),随着LET的增加，这种增加在所有屈曲角度都显著降低(范围，0.7°-1.6°)(P<.05)。
■在尸体模型中，与孤立的ACL-R状态相比，进行部分MMPH半月板切除术会响应AT和IR负荷而增加ATT和IR。然而,部分MMPH半月板切除术后进行LET手术时，在响应IR和扭矩的90°外，所有膝关节屈曲角度均显着降低，并且在膝关节屈曲15°时对AT负荷的反应显着降低。
■LET可能是ACL-R和部分MMPH半月板切除术后的有用辅助手术，以减少膝关节松弛。
■本研究的目的是确定接受ACL重建（ACL-R）和部分内侧半月板后角（MMPH）半月板切除术的膝关节LET的运动学效果。假设添加LET将减少ACL重建的膝盖的松弛。
■对照实验室研究。
■十个新鲜冷冻的人类尸体膝盖（平均年龄，41.5年）在3种载荷下使用机器人系统进行了测试：（1）胫骨前（AT）载荷的89.0N，（2）5N·m的内旋（IR）胫骨扭矩，和（3）模拟的枢轴移位-在0°时7N·m的组合外翻和5N·m的IR扭矩，15°,30°,45°,60°,膝关节弯曲90°。在4种状态下获取了运动学数据：（1）完整，(2)ACL-R,（3）ACL-R+部分MMPH半月板切除术（MMPH），和(4)ACL-R+部分MMPH半月板切除术+LET(MMPH+LET)。
■响应AT加载，与ACL-R状态相比，在所有膝关节屈曲角度下，MMPH状态下的AT平移（ATT）均显着增加，膝关节屈曲90°时增加最大(平均差，3.1mm)(P<.001)。尽管使用MMPHLET在膝关节屈曲15°时ATT显着降低（P=0.022），其他膝关节屈曲角度差异无统计学意义(P>.05)。在具有IR扭矩的MMPH中，与ACL-R状态相比，除90°外，所有膝关节屈曲角度的IR均显着增加（范围，2.8°-4.9°),随着LET的增加，这种增加在所有屈曲角度都显著降低(范围，0.7°-1.6°)(P<.05)。
■在尸体模型中，与孤立的ACL-R状态相比，进行部分MMPH半月板切除术会响应AT和IR负荷而增加ATT和IR。然而,部分MMPH半月板切除术后进行LET手术时，在响应IR和扭矩的90°外，所有膝关节屈曲角度均显着降低，并且在膝关节屈曲15°时对AT负荷的反应显着降低。
■LET可能是ACL-R和部分MMPH半月板切除术后的有用辅助手术，以减少膝关节松弛。
