More R C, Markolf K L
Division of Orthopaedic Surgery, University of California, Los Angeles 90024-1795.
J Bone Joint Surg Am. 1988 Aug;70(7):1020-31.
A Gore-Tex prosthetic ligament was inserted, with an over-the-top femoral placement, into thirteen fresh-frozen cadaver knees as a substitute for the anterior cruciate ligament. The femoral eyelet was screwed into bone and the tibial eyelet was attached to a force-transducer, which was positioned and locked on a tibial slider track to record forces in the ligament as the tibia was externally loaded. A reference position was established for the tibial eyelet so that, after the Gore-Tex ligament was implanted, the total anterior-posterior laxity of the knee (at 200 newtons of applied tibial force) matched that of the intact knee (that is, before the anterior cruciate ligament had been cut) at 20 degrees of flexion. With both ends of the ligament secured in the knee, repeated 200-newton anterior-posterior load cycles produced an increase of five to seven millimeters in the total laxity. This apparent stretch-out of the ligament could be worked out of the knee by manually flexing and extending the knee thirty times between zero and 90 degrees of flexion while a constant 200-newton force was applied to the tibial eyelet. After implantation of the Gore-Tex ligament, the laxity of the knee matched that of the intact specimen at 20 degrees of flexion and matched it within one millimeter at zero, 5, and 10 degrees of flexion. For each millimeter that the tibial eyelet was moved distally, the total anterior-posterior laxity decreased by the same amount. The anterior stiffness of the knee after implantation of the Gore-Tex ligament was always less than that of the intact specimen. With an applied extension moment of ten newton-meters, section of the anterior cruciate ligament increased hyperextension of the knee by 2.3 degrees; implantation of the Gore-Tex ligament did not restore full extension, even when the ligament was over-tightened by using a distal location for the tibial eyelet. When the eyelet was in the reference position, the ligament forces ranged from three to 319 newtons when the knee was in full extension, they rose dramatically as the knee was hyperextended, and they decreased to zero in most specimens as the knee was flexed more than 15 degrees. The pull of the quadriceps tendon against fixed resistance always increased the ligament forces. The application of tibiofemoral contact force reduced the ligament forces that were generated during a straight anterior tibial pull.(ABSTRACT TRUNCATED AT 400 WORDS)
将一条戈尔特斯（Gore-Tex）人工韧带经股骨“过顶”置入13个新鲜冷冻尸体膝关节，以替代前交叉韧带。将股骨孔眼用螺钉固定于骨上，胫骨孔眼连接到一个力传感器，该传感器置于并锁定在胫骨滑动轨道上，以便在胫骨受到向外载荷时记录韧带中的力。为胫骨孔眼确定一个参考位置，使得在植入戈尔特斯韧带后，膝关节在200牛顿胫骨作用力下的前后总松弛度与完整膝关节（即在前交叉韧带切断之前）在20度屈曲时的松弛度相匹配。在韧带两端固定于膝关节后，重复施加200牛顿的前后载荷循环，会使总松弛度增加5至7毫米。通过在0至90度屈曲之间手动屈伸膝关节30次，同时对胫骨孔眼持续施加200牛顿的力，可使韧带这种明显的伸长从膝关节中消除。植入戈尔特斯韧带后，膝关节在20度屈曲时的松弛度与完整标本的松弛度相匹配，在0度、5度和10度屈曲时，松弛度相差在1毫米以内。胫骨孔眼每向远侧移动1毫米，前后总松弛度就减少相同的量。植入戈尔特斯韧带后膝关节的前向刚度始终小于完整标本。施加10牛顿·米的伸展力矩时，切断前交叉韧带会使膝关节过伸增加2.3度；即使将胫骨孔眼置于远侧位置对韧带过度收紧，植入戈尔特斯韧带也无法恢复完全伸展。当孔眼处于参考位置时，膝关节完全伸展时韧带力在3至319牛顿之间，随着膝关节过伸，韧带力急剧上升，在大多数标本中，当膝关节屈曲超过15度时，韧带力降至零。股四头肌肌腱对抗固定阻力的牵拉总是会增加韧带力。胫股接触力的施加会降低胫骨向前直线牵拉过程中产生的韧带力。（摘要截取自400字）
