Abstract des Autors

To determine the effect of an externally applied joint-compressive load and a quadriceps muscle force on knee motion, we tested nine intact cadaveric knees and four knees after sectioning of the anterior cruciate ligament. Anteroposterior translation was measured at 0, 15, 30, 45, and 90 degrees of knee flexion after the application of an anteroposterior force of 100 N, a joint-compressive load of 0, 111, 222, 333, or 444 N, and a quadriceps force of 0 or 133 N. Both a joint-compressive load and a quadriceps force significantly decreased total anteroposterior translation by as much as 50% to 66% in intact knees and 42% to 71% in anterior cruciate ligament-sectioned knees. A substantial anterior translation was also found with the application of a joint-compressive load or a quadriceps force and no anterior force. We termed this translation an anterior neutral-position shift. The anterior neutral-position shift was significantly greater in the ligament-sectioned knees compared with the intact knees, so much so that at flexion angles greater than 15 degrees, the application of a 100-N posterior force could not translate the tibia to the most anterior position achieved in the intact knee with a 100-N anterior force. Verf.-Referat