Abstract:
Purpose: Passive tibiofemoral anterior-posterior (AP) laxity has been extensively investigated after posterior cruciate ligament (PCL) single-bundle reconstruction. However, the PCL also plays an important role in providing rotational stability in the knee. Little is known in relation to the effects of PCL single-bundle reconstruction on passive tibiofemoral rotational laxity. Gait biomechanics after PCL reconstruction are even less understood. The aim of this study was a comprehensive prospective biomechanical in vivo analysis of the effect of PCL single-bundle reconstruction on passive tibiofemoral rotational laxity, passive anterior-posterior laxity, and gait pattern. Methods: Eight patients undergoing PCL single-bundle reconstruction (seven male, one female, mean age 35.6 ± 6.6 years, BMI 28.0 ± 3.6 kg/m2) were analyzed preoperatively and 6 months postoperatively. Three of the eight patients received additional posterolateral corner (PLC) reconstruction. Conventional stress radiography was used to evaluate passive translational tibiofemoral laxity. A previously established rotometer device with a C-arm fluoroscope was used to assess passive tibiofemoral rotational laxity. Functional gait analysis was used to examine knee kinematics during level walking. Results: The mean side-to-side difference (SSD) in passive posterior translation was significantly reduced postoperatively (12.1 ± 4.4 mm vs. 4.3 ± 1.8 mm; p < 0.01). A significant reduction in passive tibiofemoral rotational laxity at 90° knee flexion was observed postoperatively (27.8° ± 7.0° vs. 19.9° ± 7.5°; p = 0.02). The range of AP tibiofemoral motion during level walking was significantly reduced in the reconstructed knees when compared to the contralateral knees at 6-month follow-up (16.6 ± 2.4 mm vs. 13.5 ± 1.6 mm; p < 0.01). Conclusion: PCL single-bundle reconstruction with optional PLC reconstruction reduces increased passive tibiofemoral translational and rotational laxity in PCL insufficient knees. However, increased passive tibiofemoral translational laxity could not be fully restored and patients showed altered knee kinematics with a significantly reduced range of tibiofemoral AP translation during level walking at 6-month follow-up. The findings of this study indicate a remaining lack of restoration of biomechanics after PCL single-bundle reconstruction in the active and passive state, which could be a possible cause for joint degeneration after PCL single-bundle reconstruction.
摘要:
目的:在后交叉韧带(PCL)单束重建后,已广泛研究了被动胫骨股前后(AP)松弛。然而,PCL在提供膝关节的旋转稳定性方面也起着重要作用。关于PCL单束重建对被动胫骨股旋转松弛的影响知之甚少。对PCL重建后的步态生物力学了解更少。这项研究的目的是对PCL单束重建对被动胫骨股旋转松弛的影响进行全面的前瞻性体内生物力学分析,被动前后松弛,和步态模式。方法:8例接受PCL单束重建的患者(7例男性,一只雌性,平均年龄35.6±6.6岁,术前和术后6个月进行BMI28.0±3.6kg/m2)分析。八名患者中有三名接受了额外的后外侧角(PLC)重建。常规应力射线照相用于评估被动平移胫骨股松弛度。使用先前建立的带有C臂荧光镜的旋转计装置来评估被动胫骨股旋转松弛度。功能步态分析用于检查水平行走过程中的膝关节运动学。结果:被动后部平移的平均左右差异(SSD)在术后显着降低(12.1±4.4mmvs.4.3±1.8mm;p<0.01)。术后观察到90°膝关节屈曲时被动胫骨股旋转松弛的显着降低(27.8°±7.0°与19.9°±7.5°;p=0.02)。在6个月的随访中,与对侧膝盖相比,重建膝盖在水平行走期间的AP胫骨股运动范围显着减小(16.6±2.4mmvs.13.5±1.6mm;p<0.01)。结论:PCL单束重建与可选的PLC重建减少了PCL不足膝关节的被动胫骨股平移和旋转松弛的增加。然而,不能完全恢复增加的被动胫骨股平移松弛,并且在6个月的随访中,患者在水平行走期间表现出膝关节运动学改变,胫骨股AP平移范围显着降低。这项研究的结果表明,在主动和被动状态下,PCL单束重建后生物力学的恢复仍然缺乏。这可能是PCL单束重建后关节退变的可能原因。