Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Decreases Passive Anterior Tibial Subluxation Compared With Isolated Anterior Cruciate Ligament Reconstruction Despite Similar Rotational Stability and Clinical Outcomes

Proximally positioned femoral grafts decrease passive anterior tibial subluxation in anterior cruciate ligament reconstruction using a posterior trans-septal portal

PURPOSE

To compare the anterior and posterior trans-septal (TS) portal approaches in anterior cruciate ligament reconstruction (ACLR) by evaluating femoral tunnel positioning and passive anterior tibial subluxation (PATS).

METHODS

A total of 205 patients who underwent primary ACLR using the outside-in technique between March 2018 and December 2021 were retrospectively enrolled. Patients were classified into two groups based on the viewing techniques: the anterior group was treated using anteromedial or anterolateral portals (n = 155), and the TS group was treated using posterior TS portal (n = 55). The relative locations of the femoral tunnel were evaluated using the deep-shallow planes (X-axis) and superior-inferior planes (Y-axis) with the quadrant method in the lateral femoral condyle on a 3-dimensional computed tomography image. Anterior tibial subluxation for the lateral and medial compartments relative to the femoral condyles was evaluated as measured on magnetic resonance imaging. Knee laxity was assessed using the pivot-shift test and stress radiography.

RESULTS

In the posterior TS group, the femoral tunnel was usually located deeper on the X-axis and more superior on the Y-axis, which corresponds to a more proximal position, than in the anterior group (deeper on the X-axis and superior on the Y-axis). Moreover, the femoral tunnel locations in this group were more compactly distributed than those in the anterior group. The TS group showed significantly better reduction of postoperative PATS in the lateral compartments than the anterior group (anterior group vs. TS group: lateral compartment, 3.2 ± 3.1 vs. 4.5 ± 3.2 mm; p = .016). Significantly better results were found in the TS group for knee stability as assessed by the pivot-shift grade (p = .044); however, there were no significant differences between the two groups with respect to patient-reported outcome measures (p > .05) and other complications (p = .090).

CONCLUSION

Our results suggest that positioning the femoral tunnel using the posterior TS portal approach may lead to better outcomes in terms of PATS and rotational stability compared to the anterior portal approach in ACLR.

Lateral extra-articular tenodesis may be more cost-effective than independent anterolateral ligament reconstruction: A systematic review and economic analysis

IMPORTANCE

Anterolateral augmentation during primary anterior cruciate ligament (ACL) reconstruction (ACLR) may lower rates of ACL graft failure. However, differences in costs between two techniques, lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR), are unclear.

OBJECTIVE

To perform a systematic review and subsequent cost-effectiveness analysis comparing LET versus ALLR in the setting of primary ACLR. The hypothesis was that LET is more cost-effective than ALLR.

EVIDENCE REVIEW

A systematic review was conducted on studies in which patients underwent primary ACLR with a concomitant LET or ALLR with minimum 24 months follow-up published between January 2013 and July 2023. Primary outcomes included ACL graft failure rates and Knee Injury and Osteoarthritis Outcome Survey-Quality of Life (KOOS-QoL) subscale scores, which were used to determine health utilities measured by quality-adjusted life years (QALYs) gained. A decision tree model with one-way and two-way sensitivity analyses compared the cost of primary ACLR with a concomitant LET, independent autograft ALLR, or independent allograft ALLR. Costs were estimated using a combination of QALYs, institution prices, literature references, and a survey sent to 49 internationally recognized high-volume knee surgeons.

FINDINGS

A total of 2505 knees undergoing primary ACLR with concomitant LET (n=1162) or ALLR (n=1343) were identified from 22 studies. There were 77 total ACL graft failures with comparable failure rates between patients receiving LET versus ALLR (2.9% vs. 3.2%, P=0.690). The average QALYs gained was slightly higher for those who received LET (0.77) compared to ALLR (0.75). Survey results revealed a 5 minute longer median self-reported operative time for ALLR (20 ​min) than LET (15 ​min). The estimated costs for LET, autograft ALLR, and allograft ALLR were $1,015, $1,295, and $3,068, respectively.

CONCLUSIONS AND RELEVANCE

Anterolateral augmentation during primary ACLR with LET is more cost-effective than independent autograft and allograft ALLR given the lower costs and comparable clinical outcomes. Surgeons may utilize this information when determining the optimal approach to anterolateral augmentation during primary ACLR, although differences in preferred technique and health care systems may influence operative efficiency and material costs.

LEVEL OF EVIDENCE

Systematic review; Level of evidence, IV.

Radiographic Investigation of Differences in Static Anterior Tibial Translation With Axial Load Between Isolated ACL Injury and Controls

BACKGROUND

Static anterior tibial translation (SATT) is radiographically measured to show the amount of tibial translation during the single-leg stance, and thus it is representative of the physiological axial load subjected to the anterior cruciate ligament (ACL) during the stance. Increased SATT has been associated with increased posterior tibial slope (PTS) and is also associated with increased graft failure.

PURPOSE

To compare the SATT value in a control population with that in a population with an isolated ACL injury, as well as to compare the effect of tibial slope on SATT between the 2 groups.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

A consecutive series of patients without ligamentous or meniscal injuries between 2019 and 2022 was reviewed. A matched consecutive cohort of patients with nonacute ACL injuries (surgery between 6 and 12 weeks after injury) without concomitant pathology was reviewed. Preoperative SATT and PTS were measured with a previously validated technique on lateral weightbearing knee radiographs. The SATT value was determined, and regression analysis was performed to investigate the relationship between SATT and PTS.

RESULTS

In total, 101 controls and 115 patients with an ACL injury were included in this study. The mean SATT was 1.31 mm (SD, 2.44 mm) and the mean PTS was 10.61° (SD, 3.28°) in the control cohort. The SATT was larger (mean, 2.27 mm; SD, 3.36 mm) in the ACL-injured cohort despite the tibial slope measurement being less in the ACL-injured cohort (mean, 9.46°; SD, 2.85°; P = .016). Linear regression analysis showed that for every 1° of increase in PTS, there was a 0.34-mm increase in SATT in the control cohort; however, there was a greater increase of 0.5 mm for every 1° of increase in PTS in the ACL-injured cohort. We found no significant differences in SATT when the cohorts were compared by age (P = .26) or sex (P = .10).

CONCLUSION

The present study reports a reference SATT value of 1.31 mm (SD, 2.44 mm) in a non-ACL-injured cohort, which was lower than in the ACL-injured cohort (mean, 2.27 mm; SD, 3.36 mm). The effect of slope on weightbearing anterior tibial translation was greater in the ACL-injured population than in the control cohort.

Editorial Commentary: Proper Anterior Cruciate Ligament Graft Choice Mitigates Against the Need for Anterolateral Ligament Reconstruction

It is not coincidence that fervor surrounding anterolateral ligament (ALL) reconstruction increased as double-bundle anterior cruciate ligament reconstruction (ACLR) enthusiasm cooled. But perhaps we shifted our focus too soon, or perhaps we shifted our focus too much. But we must remember that the ACL is primary. Increases in ACL graft diameter by 1 or 2 mm can significantly increase graft strength and decrease revision rate. Biomechanical and clinical evidence suggests that quadriceps tendon ACLR and patellar tendon ACLR demonstrates less pivot shift phenomena than hamstring ACLR. In addition, As biologically active suture tapes become more mainstream, augmented allografts are an increasingly attractive option. Proper ACL graft choice mitigates against the need for ALL reconstruction. Risk factors for anterolateral rotatory instability may include low body mass index and lateral meniscal pathology, in addition to the well-known risks such as age, gender, activity level, and revision cases. Perhaps lateral extra-articular tenodesis should be reserved for high-risk cases.