Outcomes of retro-drilled all-inside tibial tunnel vs complete tibial tunnel techniques in anterior cruciate ligament reconstruction-a comparative study

Abstract

Purpose: The all-inside tibial tunnel preparation technique of arthroscopic anterior cruciate ligament (ACL) reconstruction differs from traditional complete tibial tunnel technique in using closed tibial sockets, dual-cortical suspensory graft-fixation, quadrupled semitendinosus tendon graft and lesser bone removal. The study aims to find out if all-inside technique differs from complete tibial tunnel technique of single bundle ACL reconstruction in terms of graft dimensions, functional and clinical outcomes.

Methods: A prospective comparative study was conducted including 80 patients with isolated ACL tears, divided into 2 groups of 40 patients each without any randomization. The two techniques differed in tibial tunnel preparation. Group 1 underwent ACL reconstruction with a complete tibial tunnel drilled from the anteromedial tibial cortex and group 2 underwent all-inside tibial socket preparation. Duration of the surgery, perioperative and midterm complications were noted. All patients had 24 month follow-up. Functional outcome scores (Tegner-Lysholm knee scoring scale and IKDC score) were assessed preoperatively and postoperatively at 6 months and 24 months. Hamstring and quadriceps muscle strength was assessed preoperatively and postoperatively at 6 months, 9 months and 24 months. Visual analogue score (VAS) for knee pain was assessed preoperatively and postoperatively at day 2, 2 weeks, 6 weeks, 6 months and 24 months.

Results: Quadrupled semitendinosus tendon graft was significantly thicker than doubled semitendinosus and gracilis tendons graft (8.17 ± 0.58 vs 8.71 ± 0.4, p < 0.0001). The VAS score for knee pain at 2 and 6 weeks were lower in group 2 (5.75 ± 0.6 and 1.78 ± 1.0) as compared to group 1 (6.50 ± 0.5 and 2.5 ± 0.8) and the difference was statistically significant (P = 0.0007 and p = 0.002 respectively). There were no statistically significant differences in functional outcome scores and quadriceps muscle strength between the two groups. However, there were significant difference in hamstring power in two groups.

Conclusion: The all-inside technique has the advantages of using a single tendon graft, lesser early postoperative pain with similar clinical and functional outcomes compared to the complete tibial tunnel technique. Level of Evidence IIProspective comparative study.

Keywords: All-inside; Anterior cruciate ligament; Cortical suspensory fixation; Retro-drill; Tibial tunnel.