Factors affecting graft excursion patterns in endoscopic anterior cruciate ligament reconstruction

Abstract

The effect of femoral guide rotation in endoscopic anterior cruciate ligament (ACL) reconstruction is reviewed based on a previous report. The effect of varied offsets of the femoral guide (5.5 and 7.0 mm) are described. This is one of the few isometry studies to evaluate the knee through a practically full range of motion (0 degree-120 degrees). A 7-mm offset guide rotated to the 12:00 position yields the best single fiber and graft excursion patterns (P < 0.05). A 5.5-mm offset guide yields inferior single fiber and graft excursion patterns. Single fiber and graft isometry are similar but not identical in endoscopic ACL reconstruction. Centering the single fiber in the tibial tunnel has little effect on isometry patterns, demonstrating that the more posterior tibial positions needed for endoscopic reconstruction are acceptable from an isometry standpoint.

Anterior Cruciate Ligament Graft Isometry Is Affected by the Orientation of the Femoral Tunnel

“…[43][44][45][46][47][48][49] They noted similar findings to our study with graft lengths and forces decreasing with knee flexion from 0-degree extension and eventually increasing again with deeper knee flexion angles. 11,21, [43][44][45][46][47][48][49] All of these studies evaluated transtibial tunnel drilling except Sim et al who evaluated AM portal, outside-in, and transtibial femoral drilling techniques with hamstring grafts. They found that graft forces were no different from native ACL forces.…”

“…An actual graft composed of multiple fibers and bundles may have behaved differently from the smaller diameter FiberWire, and it is known that different locations within a transtibial graft see different forces and length changes. 43,44,48 It would not have been possible to use actual tunnels and grafts for each of the three techniques on each specimen, though we feel that our method is a reasonable compromise. When measuring tension, the initial tension was set in full extension as opposed to 30degree flexion or some other angle as may be done during surgery.…”

Integración tendinosa de plastias autólogas en túneles de diferente calibre. Estudio experimental en ovejas

“…Los estudios basados en la isometría han demostrado la posición del túnel femoral alto, en la escotadura intercondílea, en una posición poco anatómica [60] poder alcanzar la pared posterior para situar al túnel femoral (BROPHY) y evitar el pinzamiento de la plastia [116]. Estas recomendaciones sitúan el túnel tibial en la inserción del fascículo PL en la huella del LCA [257].…”

“…Las dos muestras de dos años revelaron una buena orientación de las fibras y encontraron células fusiformes. Por su parte, Cooper et al [60] vieron que los fibroblastos tendinosos proliferaron más rápidos que los fibroblastos del LCA, señalando Petersen et all [194] que la densidad de fibroblastos incide negativamente en las propiedades mecánicas del tendón.…”

Excursion of bone-patella tendon-bone grafts during the flexion–extension movement in anterior cruciate ligament reconstruction: Comparison between isometric and anatomic reconstruction techniques

“… 3 In this isometric reconstruction technique, the femoral socket was key in ensuring graft isometry. Previous studies revealed the anterior–superior border of the anatomical ACL footprint as the isometric point 4 , 5 , 6 ; however, after overdrilling a guide pin that was inserted at the point, the tunnel aperture occupied mostly the outside of the footprint. Thus, these grafts, which were least anatomical and nonphysiological, resulted in several problems such as impingement against the intercondylar notch/wall or the posterior cruciate ligament, 7 , 8 , 9 and poor control in rotational stability because of vertical graft orientation.…”