Remnant-Preserving ACL Surgery Improves Knee Stability and Function: Study
Researchers have demonstrated that the preservation of the ruptured ligament remnant in anterior cruciate ligament (ACL) reconstruction provides improved knee function and stability at no additional cost in complications. The study was published in BMC Surgery by Chunrong C. and fellow researchers. The ACL is an important stabilizer in the knee, and its reconstruction is often needed following injury to the athlete. The evidence is supportive of the clinical utility of remnant-preserving ACLR as an apparently superior alternative in suitable patients.
Researchers performed systematic searching through four major biomedical databases, PubMed, Embase, Web of Science, and the Cochrane Library, to November 6, 2024. 10 eligible studies were selected: 6 randomized controlled trials and 4 cohort studies. All studies compared remnant-preserving and standard ACLR method outcomes. The evidence quality was assessed using the Newcastle-Ottawa Scale for cohort studies and the Cochrane Risk of Bias tool for RCTs. The functional outcomes were analyzed in terms of Lysholm and International Knee Documentation Committee (IKDC) scores, knee stability in terms of KT-1000/2000 arthrometer measurements, and rates of complications. Statistical analysis was conducted based on fixed- or random-effects models depending on the extent of heterogeneity between studies.
Key Findings
Functional Improvement:
Patients who received remnant-preserving ACLR showed significantly superior Lysholm scores. WMD was 0.85 (95% CI: 0.29 to 1.42, p < 0.05), and it showed superior global knee function than the conventional technique.
Better Knee Stability
In RCTs as well as in cohort studies, remnant-preserving ACLR demonstrated superior knee stability. WMD was -0.45 (95% CI: -0.62 to -0.27, p < 0.01) in RCTs and -0.42 (95% CI: -0.62 to -0.23, p < 0.01) in cohort studies based on KT-1000/2000 measurements, indicating less anterior tibial translation and improved joint support.
No Significant Difference in IKDC Scores
The inter-group difference in IKDC scores was not statistically significant (WMD = -0.21; 95% CI: -1.68 to 1.26; p > 0.05).
No Increased Complications:
Complication rates were comparable between the two methods (Risk Ratio = 1.16; 95% CI: 0.77–1.76; p > 0.05), showing that the remnant-preserving technique does not create additional surgical hazards.
Publication Bias:
No publication bias across the studies included.
Remnant-saving ACL reconstruction results in more favorable functional results and enhanced knee joint stability without a heightened risk of complications. This evidence substantiates its increasing application in clinical practice, particularly for patients aiming for the best possible recovery and joint function following ACL injuries.
Reference:
Chen, C., Zhang, J., Bei, C. et al. Remnant-preserving techniques in anterior cruciate ligament reconstruction: a systematic review and meta-analysis. BMC Surg 25, 304 (2025). https://doi.org/10.1186/s12893-025-03034-0
