To introduce a new surgical technique for tensioning a lax ruptured anterior cruciate ligament (ACL) with good continuity and augmenting it using the double hamstring tendon.

The clinical results were obtained from 5 cases that had been followed up for more than 1 year. Most were sports injuries but one case was the result of a traffic accident. The parameters used for examining the clinical results were the Lachman test, a pivot shift test, KT-1000 arthrometer, pull stress view, IKDC and OAK score before surgery and at the last follow-up. Three cases were checked preoperatively by MRI. Three cases who had an associated posterolateral rotatory instability underwent a reconstruction using a posterolateral corner sling through the fibular head.

The Lachman test and pivot shift test, which were positive preoperatively, were converted to negative in all patients at the last follow-up. Two cases were C grade and two cases were D grade. These patients were converted to A grade, but one C grade case was converted to B grade in the IKDC score. In the OAK score, the average score was 68.5 (57 to 90) before surgery, and 91.2 (79 to 98) after surgery. In the KT-1000 arthrometer and pull stress view, the mean side-to-side difference was 5.6 (5 to 6) mm and 7 (5 to 8) mm before surgery and 1.5 (1 to 3) mm, 0.3 (0 to 1) mm, after surgery, respectively, except for one case who showed laxity of the contralateral side.

Tensioning of a lax ACL and hamstring tendon augmentation is an effective method for correcting a lax ACL to restore joint stability and preserve the remnant proprioception.