Th. Gertel et al., EFFECT OF ANTERIOR CRUCIATE LIGAMENT GRAFT TENSIONING DIRECTION, MAGNITUDE, AND FLEXION ANGLE ON KNEE BIOMECHANICS, American journal of sports medicine, 21(4), 1993, pp. 572-581
The objective of this study was to determine the biomechanical effect
of graft tensioning during reconstruction of the anterior cruciate lig
ament. We evaluated the magnitude of the tensioning force (22 or 67 N)
, the flexion angle at which the tension was applied (extension or 300
of flexion), and the direction of application of the tensioning force
(proximal, distal, or distal with a posterior force simultaneously ap
plied to the tibia) on 10 fresh cadaveric knees. The anterior cruciate
ligament was reconstructed using a bone-patellar tendon-bone graft. T
he graft was then temporarily fixed during the application of each of
12 combinations of tensioning variables listed above. After each fixat
ion, graft force and joint motion were measured during anterior tibial
loads. Tensioning direction and the flexion angle significantly affec
ted graft force and joint motion, while the magnitude of the graft ten
sioning did not. Graft forces were greater when the tensioning was app
lied at 300 of flexion. Compared with distal tensioning with and witho
ut posterior tibial force, graft forces with proximal tensioning were
greater in extension and lower in flexion. The position of the tibia r
elative to the femur was posterior and externally rotated, compared wi
th normal, for all combinations of tensioning variables in both unload
ed and anterior load states.