Summary

Technique and outcomes of using bone-patellar tendon bone autograft and LET combined with anterior closing wedge proximal tibial osteotomy to treat the failed ACLR with high posterior tibial slope in a single surgery.

Abstract

Background

Increased posterior tibial slope (PTS) results in higher load on the anterior cruciate ligament (ACL) and increased anterior tibial translation (ATT) and thereby an increased risk of ACL reconstruction (ACLR) failure. Another factor increasing both the ATT and internal rotation (i.e., the pivot shift) is insufficiency of the anterolateral structures. Previous solutions for the failed ACLR with high grade pivot shift and increased PTS include two-stage procedures due to the technical difficulty for a bone-patellar tendon-bone autograft (BPTB) harvest combined with an anterior closing wedge proximal tibial osteotomy (ACWPTO). However, single-stage surgery for a failed ACLR with an increased PTS would be beneficial because it lowers the overall risks and costs. With modern techniques for BPTB graft harvest, LET and ACWPTO we believe the technical difficulties considered in the past are no longer valid enough to avoid this combination.
Purpose/hypothesis: To evaluate the outcomes and safety of patients undergoing single stage revision ACLR, ACWPTO and LET. We hypothesized that a single-stage revision ACLR using a BPTB autograft in combination with LET and AWCPTO is safe and effective in reducing the PTS and ATT and improves patient outcomes.
Study Design: Case series; Level of evidence, 4.

Methods

This was a retrospective study of all patients going through a revision ACLR using a BPTB autograft, ACWPTO and LET at a single center from 2018 to 2023. Inclusion criteria was patients who had provided research consent, were >18 years of age with a failed ACLR, PTS of >15 degrees, had previous ACL-tunnel diameters of < 14 mm, no other ligament reconstructions were needed and had their ipsilateral patellar tendon intact. PTS was measured using mechanical axis on long weightbearing lateral x-rays and ATT was measured as the perpendicular distance between the most posterior aspect of the medial femoral condyle and the medial tibial plateau. Approval from the institutional research review committee was obtained (MF3867-2024-1).

Results

Revision ACLR using a BPTB autograft, LET and ACWPTO was performed in nine patients, all male, (mean age, 31.1 years). The ACWPTO resulted in the PTS significantly decreasing from 16.8° (range 15.1-18.9°) preoperatively to 9.3° (range 5.0-14.7°) postoperatively (p<0.001), and ATT significantly decreasing by 8.3 mm, from 14.6 mm (range 10.7-19.0 mm) preoperatively to 6.3 mm (range 1.3-11.5 mm) postoperatively (p<0.001). The side-to-side difference in ATT decreased by 8.5 mm, from 5.5 mm (range 1.6-8.8 mm) to -3.0 mm (range -7.7-2.0 mm) (p<0.001). Before surgery, all nine patients showed significant instability with Lachman test grade 2 or 3, anterior drawer test grade 1 or 2 and pivot shift test grade 2 or 3. After the surgery these clinical stability tests were reduced back to normal (grade 0) in all patients (p<0.01). The postoperative subjective International Knee Documentation Committee (IKDC) score was 79.4 (range, 60.9-95.4).

Conclusions

Single stage revision ACLR using a BPTB autograft, LET and ACWPTO in an ACL deficient knee with high grade pivot shift and increased posterior tibial slope was a safe and reliable procedure with significantly improved clinical and objective outcomes.