Summary
the All-Inside technique demonstrated equivalent clinical and knee-stability outcome along with a significant better isokinetic flexion strength at lower angular velocity and less tunnel widening at the tibial side compared to a full tibial tunnel technique with interference fixation.
Abstract
Background
The recently described "All-Inside graft-link technique" for ACL reconstruction provide bone sockets creation and graft fixation using an adjustable loop length device both on femur and tibia. Concerns exist about possible loop lengthening after fixation, leading to graft loosening and surgical failure.
Purpose
To compare the clinical, isokinetic flexion strength and radiological results of the All-Inside technique to those of a full-tibial tunnel technique for ACL reconstruction.
Methods
44 patients were retrospectively enrolled at a mean follow-up of 24±3 months (Group A: 22 patients, All-Inside technique; Group B: 22, full-tibial tunnel technique). At follow-up, all patients underwent clinical (IKDC, KSS, Tegner and Lysholm scores), knee-laxity (KT-2000), isokinetic flexion strength assessment and tunnel widening evaluation with CT scan.
Results
In Group A, a significant improvement was found for Lysholm score (p=0.01), KSS (p=0.01) and IKDC form (p=0.01) The mean side to side was 1.75 ± 1.2 mm.
In Group B, a significant improvement was found for Lysholm score (p=0.005), KSS (p=0.005) and IKDC form (p=0.005). The mean side to side difference was 2.1 ± 1.2 mm.
In group A the mean peak flexion torque was 7.2% and the mean torque at 30° was 3.1%, while in group B the mean peak flexion torque was -7.2% and the mean torque at 30° was -11% at low angular velocity (60°/sec), with better results in group A (p=0.009). Radiological evaluation showed significant less tunnel widening in group A at the middle (p=0.027) and articular (p=0.028) portion of the tibial tunnel.
Conclusion
The All-Inside technique yielded equivalent clinical and knee-stability outcome along with a significant better isokinetic flexion strength at lower angular velocity and less tunnel widening at the tibial side compared to a full tibial tunnel technique with interference fixation. Suspensory fixation with an adjustable loop length device, allowing bone stock preservation and less tunnel widening, seem to be a valid option for the tibial side which historically have been considered the weakest point in ACL reconstruction