Outcomes of Isolated Lateral Extra-articular Tenodesis for Residual Laxity Following ACL Reconstruction: A Systematic Review

Background: Despite surgical reconstruction, some patients develop persistent residual rotatory laxity following anterior cruciate ligament (ACL) reconstruction (ACLR). Lateral extra-articular tenodesis (LET) has been shown to be a successful adjunctive procedure to address anterolateral instability in high-risk patients with ACL tears. It is often performed during ACLR; however, there is growing interest in understanding possible indications for the LET as an isolated procedure. Purpose: To consolidate the current evidence on isolated LET (iLET) following ACLR, explore its indications, and evaluate outcomes such as laxity, patient-reported outcome (PRO) measures (PROMs), and complication rates. Study Design: Systematic review; Level of evidence, 4. Methods: This systematic review was conducted in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. A comprehensive literature search was performed across Ovid MEDLINE, Embase, EBM Reviews, and Emcare from inception to April 2025. Studies were eligible if they reported outcomes in patients undergoing iLET for residual laxity following ACLR with evidence of an intact ACL graft. Biomechanical, cadaveric, and non-English studies were excluded. Two reviewers independently screened studies, extracted data, and assessed methodological quality. A narrative synthesis was conducted, with descriptive statistics (frequencies, percentages, or weighted means with measures of variability) reported where appropriate. Results: Four studies (N = 69 patients, 70 knees) were included, with a mean ± SD patient age of 25.3 ± 2.9) and follow-up period of 26.3 ± 3.6 months. Patients demonstrated significant reductions in rotatory laxity following iLET, with only 6 patients reporting positive postoperative pivot shift (grade ≥1). Reported PROMs improved across all studies. Complication rates ranged from 15.8% to 36.8% while failure rates ranged from 0% to 10.5%. Conclusion: This review demonstrated that iLET may provide favorable PROs, reduction in laxity, and low failure rates in patients with residual laxity following ACLR. These findings suggest that the use of iLET may be a viable option for residual laxity following ACLR with evidence of an intact ACL graft; however, a limited number of reporting studies and small sample size require these results to be interpreted with caution.