Summary

Slope-reducing osteotomies are a viable option for revision patients undergoing anterior cruciate ligament reconstruction with posterior tibial slopes above 12 degrees.

Abstract

Purpose

Elevated posterior tibial slope (PTS) has been associated with a significantly greater risk of failure after anterior cruciate ligament reconstruction (ACLR), with correction of slope being a topic of recent interest to reduce revision rates. Therefore, the purpose of this systematic review was to (1) summarize indications/inclusion criteria and contraindications/exclusion criteria, operative techniques and details, rehabilitation timelines for slope-reducing osteotomies with concomitant primary or revision ACLR, and (2) summarize the radiographic and clinical outcomes that follow these types of surgeries.

Methods

Three databases (MEDLINE, PubMed and EMBASE) were searched on May 2, 2024, for studies with patients undergoing ACLR with concomitant slope-reducing osteotomy. The authors adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Revised Assessment of Multiple Systematic Reviews (R-AMSTAR) guidelines and Cochrane Handbook for Systematic Reviews of Interventions. Outcomes included indications and contraindications for slope-reducing osteotomies, PTS, valgus or varus alignment, measurement of patellar height, patient reported outcome measures (PROMs), measures of instability such as Lachman and pivot-shift test results, rates of return to sport, rates of and complications and re-ruptures. DerSimonian and Laird random effects models were used to generate Forest Plots and I2 values to evaluate heterogeneity. Data was not pooled using meta-analysis due to the level of evidence of included studies.

Results

Twelve studies of level IV evidence comprising 386 patients (19.6% female, 10 studies) with a mean age of 28.2 (range of means; 22.4-30.3, 11 studies) years were included. Eight of twelve (66.7%) studies reported an indication for slope-reducing osteotomy being a PTS of 12 degrees in revision or re-revision cases. Typical exclusion criteria for osteotomy reported by the ten included studies included other ligamentous injuries of the knee (reported by five studies, 50%), knee hyperextension of five to ten degrees (reported by four studies, 40%), and concomitant knee osteoarthritis (reported by four studies, 40%). Postoperative Lysholm and International Knee Documentation Committee (IKDC) scores ranged from 74.5-90.9 and 69.1-87.4, respectively. At latest follow-up, grade one pivot shift rates ranged from 0-39%, and grade two to three rates ranged from 0-26%, (I2 = 0%). Rates of return to sport (RTS) at any and pre-injury level ranged from 80-100% (I2 = 0%) and 25-100%, (I2 = 63%), respectively. Rates of postoperative recurvatum ranged from 15-44% (I2 = 33%). Re-rupture rates ranged from 0-8.7% (I2 = 0%). Hardware irritation, postoperative hematoma, and chronic regional pain syndrome (CRPS) was other reported complications.

Conclusion

The most common indication for slope-reducing osteotomies with concurrent ACLR is in the revision setting in patients with a PTS above 12 degrees. Slope-reducing osteotomies improve PROMs and may improve instability and retear rates. This surgery is associated with a high level of return to sport at any level, with relatively low rates of re-rupture. Complications with osteotomy include postoperative recurvatum, postoperative hyperextension, and hardware removal.