Summary

The study evaluates in vivo the ability of an isolated lateral extrarticular tenodesis to improve both subjective and objective stability in ACL deficient knees

Abstract

Objective

anterolateral tenodesis (ALT) is nowadays widely used in association with anterior cruciate ligament (ACL) reconstruction. Results of its isolated use have not been described since time. The last reports about isolated use were about more aggressive techniques associated with a slow rehabilitation protocol. We believe that with some specific indication the use of an isolated ALT is clinically useful. Despite few cadaveric investigations have been done about its mechanical utility, so far, no clinical analysis has been carried out. The aim of the present work is to present clinical results of isolated ALT.

Method

38 patients undergone isolated modified Lemaire ALT were prospectively evaluated. Indication for isolated ALT were: 1) ACL rupture in patients over 55 years old (18 patients) 2) patients undergoing the first step of two-stage revision ACL reconstruction (20 patients). A quantitative assessment of knee instability was performed using KT1000 arthrometer and KiRA inertial sensor. The first was used preoperatively and at each follow up (FU). KiRA was used preoperatively before and under anaesthesia, postoperatively under anaesthesia and at each FU. Single vertical jump test (SVJT) and range of motion (ROM) were evaluated preoperatively and at each FU. FU were carried out at 6 weeks, 4 months, 1 year (the last only in group 1). IKDC and Lysholm scores have been recollected preoperatively and at last follow up.

Results

100% of the patients complained giving way sensation preoperatively, in all cases this feeling disappeared at last follow up. 24 patients (78,5%) were unable to perform SVJT before the operation, 18 (64%) were able ad 6 weeks postoperatively, 35 (92,1%) at 4 months FU, 100% at 1-year FU. No postoperative complication neither ROM deficit were observed. The mean side-to-side difference in rotational acceleration of the tibia during pivot shift test measured with KiRA decreased significantly both under anaesthesia (3,2 ± 4,3 preoperatively ; 1,1 ± 1,7 postoperatively; p<0,001) and without the effect of the anaesthesia (2,6 ± 3,9 preoperatively ; 0,9 ± 1,6 last FU; p<0,001). The mean side-to-side difference in anterior tibial translation measured with KiRA decreased significantly both under anaesthesia (7,2 ± 2,1 preoperatively ; 4,3 ± 1,4 postoperatively; p=0,007) and without the effect of the anaesthesia (5,6 ± 2,6 preoperatively , 3,9 ± 1,1 last FU; p=0,014). Also the mean side-to-side difference measured with KT1000 resulted significative (4,9 ± 2,3 preoperatively; 3,1 ± 1,4 last FU p=0,029). All the postoperative analysis made from the first to the last FU didn’t show any significative variation both in rotational acceleration and in anterior tibial translation. Both for IKDS and Lysholm score we detected a significant improvement (p<0,001) between pre and postoperative evaluation.

Conclusion

in patients with an ACL injury, isolated modified Lemaire ALT can significantly reduce the pivot-shift phenomenon, the anterior tibial translation and the subjective knee instability. Up to 1 year follow up the improvements in knee stability obtained immediately after the operation didn’t decreased.