Scanlan Sean F, Donahue Joseph P, Andriacchi Thomas P
Department of Mechanical Engineering, Stanford University, Stanford, CA, USA.
Sports Orthopedic and Rehabilitation Medicine Associates (SOAR), Redwood City, CA, USA.
Knee. 2014 Jan;21(1):74-9. doi: 10.1016/j.knee.2013.06.003. Epub 2013 Jul 3.
Restoration of anterior tibial stability while avoiding knee extension deficit are a common goal of anterior cruciate ligament (ACL) reconstruction. However, achieving this goal can be challenging. The purpose of this study was to determine whether side-to-side differences in anterior tibial neutral position and laxity are correlated with knee extension deficit in subjects 2 years after ACL reconstruction.
In the reconstructed and contralateral knees of 29 subjects with transtibial reconstruction, anterior tibiofemoral neutral position was measured with MRI and three-dimensional modeling techniques; terminal knee extension at heel strike of walking and during a seated knee extension were measured via gait analysis; and anterior laxity was measured using the KT-1000.
Knees that approached normal anterior stability and anterior tibial position had increased extension deficit relative to the contralateral knee. On average the reconstructed knee had significantly less (2.1±4.4°) extension during active extension and during heel strike of walking (3.0±4.3º), with increased anterior neutral tibial position (2.5±1.7 mm) and anterior laxity (1.8±1.0 mm). There was a significant correlation between side-to-side difference in anterior neutral tibial position with both measures of knee extension (walking, r=-0.711, p<0.001); active knee extension, r=-0.544, p=0.002).
The results indicate a relationship between the loss of active knee extension and a change in anterior neutral tibial position following non-anatomic transtibial ACL reconstruction. Given the increasing evidence of a link between altered kinematics and premature osteoarthritis, these findings provide important information to improve our understanding of in vivo knee function after ACL reconstruction.
恢复胫前稳定性同时避免膝关节伸直受限是前交叉韧带（ACL）重建的共同目标。然而，实现这一目标可能具有挑战性。本研究的目的是确定ACL重建术后2年，胫前中立位和松弛度的左右差异是否与膝关节伸直受限相关。
对29例行经胫骨重建的受试者的重建膝关节和对侧膝关节，采用MRI和三维建模技术测量胫股前中立位；通过步态分析测量步行足跟触地时和坐位伸膝时的终末膝关节伸直度；使用KT-1000测量前向松弛度。
与对侧膝关节相比，接近正常前向稳定性和胫前位置的膝关节伸直受限增加。平均而言，重建膝关节在主动伸直和步行足跟触地时的伸直度明显更小（分别为2.1±4.4°和3.0±4.3°），胫前中立位增加（2.5±1.7 mm），前向松弛度增加（1.8±1.0 mm）。胫前中立位的左右差异与两种膝关节伸直度测量值之间均存在显著相关性（步行时，r=-0.711，p<0.001；主动膝关节伸直时，r=-0.544，p=0.002）。
结果表明，非解剖学经胫骨ACL重建后，主动膝关节伸直丧失与胫前中立位改变之间存在关联。鉴于运动学改变与早发性骨关节炎之间的联系证据越来越多，这些发现为增进我们对ACL重建后体内膝关节功能的理解提供了重要信息。
