Summary

In patients with ACL graft failure and increased tibial slope, anterior closing wedge high tibial osteotomy provides a safe and reliable technique to control ACL graft re-tear and offer good functional outcome on the midterm.

Abstract

Background

Increased tibial slope is correlated with increased tibial translation and higher failure rates of ACL reconstruction. Cadaveric studies have shown that slope-reducing high tibial osteotomy (SR HTO) decreases ACL-graft forces and anterior tibial translation under axial load. However, the effect of SR HTO on ACL revision outcomes has not been comprehensively analyzed on the midterm.

Purpose

To evaluate the midterm functional outcomes after slope-reducing osteotomy associated with revision ACL reconstruction.
Study design: prospective cohort study; level of evidence, 2.

Methods

41 consecutive patients with ACL reconstruction failure and increased tibial slope (18±2.7 degrees) were included. Tibial slope was calculated from full length standing lateral views using the tibial mechanical axis as a reference. Age 25±5.9 years, sex ratio 1.4, BMI 24.6±4.4 Kg/m2. Revision was staged in two procedures in all cases: first surgery for SR HTO and tunnels bone grafting; second for reimplantation of ACL graft. The amount of slope reduction was measured with a target of slope at 6 to 8 degrees. The SR HTO was performed by an anterior approach with a tibial tubercle osteotomy for access. It was guided by a 3D printed patient-specific cutting jig to avoid alteration of coronal plane alignment and it was fixed with staples. Patients were followed for 3±1.4 years. Adverse events occurred in 9.7%: secondary displacement (2/41), deep infection (1/41), delayed union (1/41). At the time of follow-up: ACL-RSI 48.8±22.6, IKDC 60.1±14.9, no recurrence in ACL graft failure. We onserved no iatrogenic coronal plane alterations and no tibial slope over/under correction on postoperative EOS long standing AP and lateral x-rays. Secondary knee hyperextension was not reported. Return to sport was observed in 70.7% (29/41) with half of these patients (15/29) involved in level I sports according to the classification by Hefti et al.

Conclusion

In patients with ACL graft failure and increased tibial slope, anterior closing wedge high tibial osteotomy provides a safe and reliable technique to control ACL graft re-tear and offer good functional outcome on the midterm.