Indications and outcomes of simultaneous high tibial osteotomy and ACL reconstruction

PURPOSE: The purpose of this study was to systematically review the existing literature reporting surgical outcomes of simultaneous high tibial osteotomy (HTO) and anterior cruciate ligament reconstruction (ACLR) in anterior cruciate ligament deficient (ACLD) knees. METHODS: This study was conducted per the methods of the Cochrane Handbook for Systematic Reviews of Intervention, with findings reported per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The electronic databases MEDLINE, EMBASE, and PubMed were searched for relevant studies and pertinent data was extracted. Studies reporting post-operative outcomes following simultaneous HTO and ACLR in ACLD knees were included. RESULTS: The search identified 515 studies, of which 18 (n = 516) were included. The mean MINORS scores for non-comparative and comparative studies were 11.6 ± 1.34 and 17.3 ± 1.9, respectively. Simultaneous HTO and ACLR resulted in improved functional subjective patient outcomes across a variety of scales. Simultaneous HTO and ACLR was effective in correcting varus angulation, with the post-operative mechanical angle ranging from 0.3° valgus to 7.7° valgus. The reported complication rate ranged from 0 to 23.5%. Across six studies, a total of 13 (6.5%) patients required revision HTO; while across four studies, 20 (17.5%) patients had failure of the ACL graft, with one receiving revision ACLR. CONCLUSIONS: Combined HTO and ACLR may be indicated in patients with ACLD knees with varus angulation. This systematic review found that the combined surgery resulted in significant improvement in post-operative functional subjective outcomes. However, it remains unclear if HTO with ACLR is superior to ALCR or HTO alone due to the lack of comparative studies. Overall, HTO with ACLR was found to have low rates of complications, re-ruptures, and need for revision surgery. This review found that patients continued to have progression of OA despite combined HTO with ACLR. Future research is required to better understand the effects of combined HTO and ACLR compared to ACLR or HTO alone and to evaluate the long-term post-operative progression of medial compartment OA following combined HTO and ACLR. LEVEL OF EVIDENCE: IV.