A Biomechanical Study of Graft Fixation in Posterior Cruciate Ligament Reconstruction / 대한정형외과학회잡지

Injuries of the posterior cruciate ligament have almost universally been treated nonoperatively in the past due to indignity of this complex structure. Recent studies have shown new informations on the anantomical, histological, biomechanical characteristics of the Posterior cruciate ligament PCL), and thereby interest of reconstruction surgery is increasing. But intraarticular PCL reconstruction still remains one of the most challenging problems in knee surgery. Although, various types of graft and surgical techniques have been used for reconstruction, results of surgery has been variable. In this study, three different methods of graft fixation for PCL reconstruction are evaluated biomechanically to determine the effect on mechanical property of reconstructed PCL using 30 porcine knees. Grafts used in this study were bone-patellar tendon-bone fixed with interference screw and Achilles tendon tied with suture. Additionally, five original PCLs were also tested by Instron universal testing instrument to determine its mechanical proprety. Tensile test was performed at extended knee position. It was demonstrated that mechanical strength of bone-patellar tendon-bone graft is superior to that of Achilles tendon graft. All of the failures of bone-patellar tendon-bone graft and Achilles tendon graft occurred at tibial fixation site whereas original PCLs which failed at proximal midsubstance of ligament. In conclusion, tensile strength of Bone-patellar tendon-bone graft used for PCL reconstruction is higher than that of Achilles tendon but latter can be used in terms of as clinical meanings.

Radiologic assessment of Endoscopically reconstructed ACL using Bone - patellar tendon - bone / 대한정형외과학회잡지

Endoscopic ACL reconstruction using bone-patellar tendon-bone has been considered the gold standard in the field of reconstructive ACL surgery. Technically, graft must be placed at isometric point. But it is difficult to evaluate the placement of graft postoperatively. The purpose of this study is to determine the radiological ideal position of graft by comparing postoperative results with the graft placement. Seventy cases of endoscopic ACL reconstruction were reviewed and classified according to the femoral and tibial graft position on radiologic imaging. The femoral graft position was classified in relation to angle of graft on anterior position view and distance from posterior margin of graft to the inner surface of posterior cortex on lateral view. The tibial graft position was classified in relation to intercondylar eminence on anterior posterior view and lateral view. Knee score (modified Marshall, Lysholum), manual anterior instability test (Lachman test, Pivot shift test) and arthrometer measurement were checked to evaluate postoperative results in each case. The results of this study implicate that knee joint in which femoral graft was oriented at direction of 11 o clock centring around 68 degree respect to tibial joint and placed within 3mm from posterior cortex showed higher knee score and lesser laxity. In cases of tibial side, the graft oriented to intercondylar eminence (AP view) and placed anterior to intercondylar eminence (lateral view) showed higher knee score and lesser laxity.