Meyer Eric G, Baumer Timothy G, Haut Roger C
Experimental Biomechanics Laboratory, College of Engineering, Lawrence Technological University, 21000 West Ten Mile Road, Southfield, MI 48075, USA.
J Biomech Eng. 2011 Jan;133(1):011012. doi: 10.1115/1.4003135.
Knee hyperextension has been described as a mechanism of isolated anterior cruciate ligament (ACL) tears, but clinical and experimental studies have produced contradictory results for the ligament injuries and the injury sequence caused by the hyperextension loading mechanism. The hypothesis of this study was that bicruciate ligament injuries would occur as a result of knee hyperextension by producing high tibio-femoral (TF) compressive forces that would cause anterior translation of the tibia to rupture the ACL, while joint extension would simultaneously induce rupture of the posterior cruciate ligament (PCL). Six human knees were loaded in hyperextension until gross injury, while bending moments and motions were recorded. Pressure sensitive film documented the magnitude and location of TF compressive forces. The peak bending moment at failure was 108 N m±46 N m at a total extension angle of 33.6 deg±11 deg. All joints failed by simultaneous ACL and PCL damages at the time of a sudden drop in the bending moment. High compressive forces were measured in the anterior compartments of the knee and likely produced the anterior tibial subluxation, which contributed to excessive tension in the ACL. The injury to the PCL at the same time may have been due to excessive extension of the joint. These data, and the comparisons with previous experimental studies, may help explain the mechanisms of knee ligament injury during hyperextension. Knowledge of forces and constraints that occur clinically could then help diagnose primary and secondary joint injuries following hyperextension of the human knee.
膝关节过度伸展被描述为孤立性前交叉韧带（ACL）撕裂的一种机制，但临床和实验研究对于韧带损伤以及由过度伸展加载机制导致的损伤顺序产生了相互矛盾的结果。本研究的假设是，膝关节过度伸展通过产生高的胫股（TF）压缩力，导致胫骨向前移位从而撕裂ACL，同时关节伸展会同时诱发后交叉韧带（PCL）断裂，进而导致双交叉韧带损伤。对六个 cadaveric 膝关节进行过度伸展加载直至出现明显损伤，同时记录弯矩和运动情况。压敏膜记录了TF压缩力的大小和位置。在总伸展角度为33.6°±11°时，失效时的峰值弯矩为108 N·m±46 N·m。所有关节均在弯矩突然下降时同时出现ACL和PCL损伤而失效。在膝关节前部区域测量到高压缩力，这可能导致了胫骨前半脱位，进而导致ACL过度紧张。同时PCL的损伤可能是由于关节过度伸展所致。这些数据以及与先前实验研究的比较，可能有助于解释膝关节过度伸展期间韧带损伤的机制。了解临床上发生的力和限制因素，进而有助于诊断人类膝关节过度伸展后的原发性和继发性关节损伤。
