Incidence and Risk Factors for Residual High-Grade Pivot Shift After ACL Reconstruction With or Without a Lateral Extra-articular Tenodesis

Background: Anterior cruciate ligament (ACL) reconstruction (ACLR) has higher failure rates in young active patients returning to sports as compared with older, less active individuals. Augmentation of ACLR with an anterolateral procedure has been shown to reduce failure rates; however, indications for this procedure have yet to be clearly defined. Purpose/Hypothesis: The purpose of this study was to identify predictors of ACL graft failure in high-risk patients and determine key indications for when hamstring ACLR should be augmented by a lateral extra-articular tenodesis (LET). We hypothesized that different preoperative characteristics and surgical variables may be associated with graft failure characterized by asymmetric pivot shift and graft rupture. Study Design: Case-control study; Level of evidence, 3. Methods: Data were obtained from the Stability 1 Study, a multicenter randomized controlled trial of young active patients undergoing autologous hamstring ACLR with or without a LET. We performed 2 multivariable logistic regression analyses, with asymmetric pivot shift and graft rupture as the dependent variables. The following were included as predictors: LET, age, sex, graft diameter, tear chronicity, preoperative high-grade knee laxity, preoperative hyperextension on the contralateral side, medial meniscal repair/excision, lateral meniscal repair/excision, posterior tibial slope angle, and return-to-sports exposure time and level. Results: Of the 618 patients in the Stability 1 Study, 568 with a mean age of 18.8 years (292 female; 51.4%) were included in this analysis. Asymmetric pivot shift occurred in 152 (26.8%) and graft rupture in 43 (7.6%). The addition of a LET (odds ratio [OR], 0.56; 95% CI, 0.37-0.83) and increased graft diameter (OR, 0.62; 95% CI, 0.44-0.87) were significantly associated with lower odds of asymmetric pivot shift. The addition of a LET (OR, 0.40; 95% CI, 0.18-0.91) and older age (OR, 0.83; 95% CI, 0.72-0.96) significantly reduced the odds of graft rupture, while greater tibial slope (OR, 1.15; 95% CI, 1.01-1.32), preoperative high-grade knee laxity (OR, 3.27; 95% CI, 1.45-7.41), and greater exposure time to sport (ie, earlier return to sport) (OR, 1.18; 95% CI, 1.08-1.29) were significantly associated with greater odds of rupture. Conclusion: The addition of a LET and larger graft diameter were significantly associated with reduced odds of asymmetric pivot shift. Adding a LET was protective of graft rupture, while younger age, greater posterior tibial slope, high-grade knee laxity, and earlier return to sport were associated with increased odds of graft rupture. Orthopaedic surgeons should consider supplementing hamstring autograft ACLR with a LET in young active patients with morphological characteristics that make them at high risk of reinjury.

Section: Discussionmentioning

confidence: 89%

Section: Discussionmentioning

confidence: 96%

Predictors of Graft Failure in Young Active Patients Undergoing Hamstring Autograft Anterior Cruciate Ligament Reconstruction With or Without a Lateral Extra-articular Tenodesis: The Stability Experience

Firth¹,

Bryant²,

Litchfield

et al. 2022

“…Novaretti et al 34 revealed that partial lateral meniscectomy affected knee stability and predisposed knees to further injuries even in ACL-intact knees. According to another study conducted by Jacquet et al, 19 repairing a preexisting meniscal lesion was more effective than LET in avoiding residual pivot shift. Based on their findings, it makes sense that partial lateral meniscectomy resulted in inferior graft maturity of the TTG in our study.…”

Section: Discussionmentioning

confidence: 88%

Effect of Anterolateral Structure Augmentation on Graft Maturity After Anterior Cruciate Ligament Reconstruction: A Clinical and MRI Follow-up of 2 Years

Chen

et al. 2022

Background: Anterolateral structure augmentation (ALSA) has been applied to prevent residual rotatory instability and lower clinical failure rates after anterior cruciate ligament (ACL) reconstruction (ACLR); however, the effect of combined ALSA on the maturity of ACL grafts remains unknown. Purpose: To evaluate the graft maturity and patient–reported outcomes in patients who underwent double–bundle ACLR with or without ALSA. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 92 patients who underwent double–bundle ACLR between January 2016 and July 2019 were included in the present study—44 patients with isolated ACLR (ACLR group) and 48 patients with combined ACLR and ALSA (ALSA group). Demographic characteristics, intraoperative findings, and patient–reported outcomes were prospectively collected. On postoperative magnetic resonance imaging at the 2–year follow–up, the signal–to–noise quotient (SNQ) values were separately calculated for 6 sections of the ACL graft, including the femoral intratunnel graft (FTG), intra–articular graft (IAG), and tibial intratunnel graft (TTG) of the anteromedial bundle (AMB) and the posterolateral bundle (PLB). Superior graft maturity was usually indicated by lower SNQ values. Results: The rates of return to preinjury sports were 47.9% and 27.3% in the ALSA and ACLR groups, respectively (difference, 20.6% [95% CI, 1.3%-40%]; P = .042). The AMB demonstrated significantly lower SNQ values in the ALSA group than in the ACLR group (FTG, 7.04 ± 3.65 vs 9.44 ± 4.51 [ P = .006]; IAG, 6.62 ± 4.19 vs 8.77 ± 5.92 [ P = .046]; TTG, 6.93 ± 3.82 vs 8.75 ± 4.55 [ P = .040]). The SNQ values were significantly lower in the ALSA group for 2 of the 3 sections of the PLB (IAG, 7.73 ± 4.61 vs 9.88 ± 5.61 [ P = .047]; TTG, 5.88 ± 3.10 vs 8.57 ± 4.32 [ P = .001]). Partial lateral meniscectomy was correlated with higher SNQ values of the TTG in the AMB (β = 0.27; P = .009) and the PLB (β = 0.25; P = .008), with both groups pooled. Higher body mass index, smaller ACL graft–Blumensaat line angles, larger AMB graft diameters, and lower postoperative Tegner scores were also associated with inferior maturity in specific regions of the ACL graft. Conclusion: A combination of ACLR and ALSA is a desirable option to improve the maturity of ACL grafts for patients who are young or expected to return to pivoting sports. Meanwhile, further investigations with higher levels of evidence and longer periods of follow–up are warranted.

“…Some researchers have suggested that lateral extra-articular procedures should be considered in patients at high risk of clinical failure; however, the definition of “high risk” varied among studies. 3,6,8,13,35 It remains difficult to predict whether a specific patient would experience failure of ACLR using the above relative risk ratios, because multiple factors should be considered. Given the superiority of machine learning analysis in validating the model with combinations of all included variables, it would play an important role in quantifying the patient-specific risk of adverse outcomes with a risk calculator and making decisions for individualized treatment.…”

Section: Discussionmentioning

confidence: 99%

Predicting the Objective and Subjective Clinical Outcomes of Anterior Cruciate Ligament Reconstruction: A Machine Learning Analysis of 432 Patients

Zhang

et al. 2022

Background: Sports levels, baseline patient-reported outcome measures (PROMs), and surgical procedures are correlated with the outcomes of anterior cruciate ligament reconstruction (ACLR). Machine learning may be superior to conventional statistical methods in making repeatable and accurate predictions. Purpose: To identify the best-performing machine learning models for predicting the objective and subjective clinical outcomes of ACLR and to determine the most important predictors. Study Design: Case-control study; Level of evidence, 3. Methods: A total of 432 patients who underwent anatomic double-bundle ACLR with hamstring tendon autograft between January 2010 and February 2019 were included in the machine learning analysis. A total of 15 predictive variables and 6 outcome variables were selected to validate the logistic regression, Gaussian naïve Bayes machine, random forest, Extreme Gradient Boosting (XGBoost), isotonically calibrated XGBoost, and sigmoid calibrated XGBoost models. For each clinical outcome, the best-performing model was determined using the area under the receiver operating characteristic curve (AUC), whereas the importance and direction of each predictive variable were demonstrated in a Shapley Additive Explanations summary plot. Results: The AUC and accuracy of the best-performing model, respectively, were 0.944 (excellent) and 98.6% for graft failure; 0.920 (excellent) and 91.4% for residual laxity; 0.930 (excellent) and 91.0% for failure to achieve the minimal clinically important difference (MCID) of the Lysholm score; 0.942 (excellent) and 95.1% for failure to achieve the MCID of the International Knee Documentation Committee (IKDC) score; 0.773 (fair) and 70.5% for return to preinjury sports; and 0.777 (fair) and 69.2% for return to pivoting sports. Medial meniscal resection, participation in competitive sports, and steep posterior tibial slope were top predictors of graft failure, whereas high-grade preoperative knee laxity, long follow-up period, and participation in competitive sports were top predictors of residual laxity. High preoperative Lysholm and IKDC scores were highly predictive of not achieving the MCIDs of PROMs. Young age, male sex, high preoperative IKDC score, and large graft diameter were important predictors of return to preinjury or pivoting sports. Conclusion: Machine learning analysis can provide reliable predictions for the objective and subjective clinical outcomes (graft failure, residual laxity, PROMs, and return to sports) of ACLR. Patient-specific evaluation and decision making are recommended before and after surgery.