Gj. Oritz et al., ISOMETRY OF THE POSTERIOR CRUCIATE LIGAMENT - EFFECTS OF FUNCTIONAL LOAD AND MUSCLE FORCE APPLICATION, American journal of sports medicine, 26(5), 1998, pp. 663-668
The effects of functional load and muscle force application on isometr
y of the posterior cruciate ligament were determined. Eight fresh-froz
en cadaver knees were mounted in a custom-designed rig. A full range o
f motion and muscle forces were applied through the quadriceps, hamstr
ing, and gastrocnemius tendons during a simulated static squat maneuve
r. The low-load isometric posterior cruciate ligament point was locate
d 5.63 mm proximal and 0.18 mm anterior to the anatomic center of the
posterior cruciate ligament origin on the femur. The high-load state,
with no gastrocnemius and hamstring muscle forces applied, shifted the
isometric point 6.32 mm proximal and 6.72 mm anterior (P < 0.05). Loa
ding the hamstring and gastrocnemius muscles also shifted the isometri
c point (P < 0.05). This study indicated that the most isometric regio
n of the posterior cruciate ligament femoral attachment changed signif
icantly when functional loads and muscle forces were applied to the kn
ee. This finding may have implications for both surgical reconstructio
n and rehabilitation of the posterior cruciate ligament-injured knee.