The Role of Lateral Extra-articular Tenodesis in Anterior Cruciate Ligament Reconstruction and Treatment of Rotatory Knee Instability: a Scoping Review

Anterior Cruciate Ligament Reconstruction with Lateral Extra-Articular Tenodesis is Associated with Reduced Risk for Revision Anterior Cruciate Ligament Reconstruction in an Insurance Claims Database

PURPOSE

To analyze a large, cross-sectional sample of patients from an administrative database for trends in the yearly utilization of either isolated anterior cruciate ligament (ACL) reconstruction or concomitant ACL reconstruction with lateral extra-articular tenodesis (LET) for the treatment of ACL injury, and to compare the cumulative incidence of 5-year reoperations and 90-day emergency visits for each treatment modality.

METHODS

International Classification of Diseases (ICD), Tenth Revision and Current Procedural Terminology (CPT) codes were used to query the PearlDiver database between October 2015 to October 2022 to identify patients with a diagnosis of ACL injury undergoing either isolated ACL reconstruction (ACLR) or ACL reconstruction with concomitant LET (ACLR/LET). Propensity score matching was performed on the basis of age, sex, Charlson Comorbidity Index (CCI), overweight or obesity (BMI > 25.0) and tobacco use. Kaplan-Meier survival analysis was used to estimate 5-year cumulative incidence of reoperations (revision ACL reconstruction, meniscus debridement/repair, adhesion lysis, knee joint manipulation, total knee arthroplasty) for each group.

RESULTS

There were 1022 patients that underwent ACLR/LET, and 64,504 patients who underwent ACLR for a diagnosis of ACL injury; following 1:1 propensity matching, 1022 patients remained in each group. Patient counts for ACLR/LET increased yearly during the study period for every year except 2020, with greater than 20% increases annually after 2017. Kaplan-Meier analysis of revision ACL reconstruction in propensity-matched groups showed a 5-year cumulative incidence of 2.6% for patients undergoing ACLR/LET and 4.9% for ACLR [HR = 0.37 (95% CI 0.18-0.74), p = 0.005]. There were no significant differences between groups any other secondary event or postoperative complications.

CONCLUSION

ACL reconstruction with LET is increasingly utilized to treat patients with ACL tears and demonstrates decreased risk for revision ACL reconstruction without increased risk for complications compared to patients treated with isolated ACL reconstruction.

LEVEL OF EVIDENCE

Level III, Retrospective Matched Comparative Series.

The Role of Isolated Lateral Extra-Articular Tenodesis in Managing Residual Pivot Shift After Primary Anterior Cruciate Ligament Reconstruction and a New Medial Meniscal Tear

Background

Persistent mildly abnormal knee kinematics after anterior cruciate ligament (ACL) reconstruction (ACLR) is an ongoing clinical problem.

Purpose

To compare the clinical outcomes of revision ACLR (rACLR), rACLR and lateral extra-articular tenodesis (LET), or isolated LET in patients with a grade ≥2 pivot shift after ACLR with an intact or partially torn graft and a new, symptomatic medial meniscal tear.

Study Design

Cohort study; Level of evidence, 3.

Methods

A retrospective review of all patients with a new, symptomatic medial meniscal tear diagnosed after a primary ACLR was performed. Patients were included if they demonstrated a grade ≥2 pivot shift on physical examination with an intact or partially torn ACL graft. Exclusion criteria included complete graft rupture. The senior author's management evolved in a practice change design from rACLR to rACLR with LET, to isolated LET over the study period. The primary outcomes were the International Knee Documentation Committee (IKDC), Lysholm, and Tegner patient-reported outcomes (PROs) at 2 years postoperatively.

Results

A total of 47 patients, with 16 in the rACLR group, 12 in the rACLR and LET group, and 19 in the isolated LET group were included. Baseline characteristics between groups were similar. At 2 years, the rACLR group IKDC score was 86.1 ± 6.6 and was lower than the rACLR and LET group (91.9 ± 4.4; P = .009; 95% CI, -10.4 to -1.2) and the isolated LET group scores (91.7 ± 3.0; P = .004; 95% CI, -9.7 to -1.6). The Lysholm score was lower in the rACLR group (85.8 ± 6.3) when compared with the rACLR and LET group (91.8 ± 4.6; P = .03; 95% CI, -11.8 to -0.39). There was no difference in any Tegner scores at 2 years (P = .09).

Conclusion

In patients with grade ≥2 pivot shift after an ACLR with an intact or partially torn graft and a new, symptomatic medial meniscal tear, the addition of an LET with or without rACLR led to improved PROs compared with an isolated rACLR. An isolated LET in this patient population should be considered an acceptable treatment option.

Correlation of Increased Lateral Tibial Slope With Baseline Tibial Position in Intact Knees and Side-to-Side Anterior Tibial Translation for Knees With ACL Tears

BACKGROUND

Anterior cruciate ligament (ACL) stress techniques-including single-leg stress radiographs, Telos, and KT-1000 arthrometer-are highly accessible and can provide additional diagnostic information to assess ACL and ACL graft integrity. The degree of anterior tibial translation (ATT) may be useful in guiding treatment when a diagnosis on magnetic resonance imaging is not conclusive or for judging if additional treatments, such as anterolateral complex augmentation, may be necessary.

PURPOSE/HYPOTHESIS

The purpose of this study was to evaluate the effect of increasing posterior tibial slope (PTS) on baseline tibial position (BTP) and side-to-side differences (SSD) in ATT. A secondary purpose was to perform a subgroup analysis of SSD in ATT for patients with a PTS of ≥12° versus <12°, as well as for acute (<6 weeks from injury) versus chronic (≥6 weeks from injury or ACL graft tear) ACL tears. It was hypothesized that the BTP in normal intact knees would increase linearly with the PTS and there would be an increased SSD in ATT when comparing ACL-injured and ACL-intact knees.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Bilateral ACL stress radiographs were assessed from patients with primary ACL and ACL graft tears between March 2023 and March 2024. Bilateral stress views were obtained by single-leg full-length lateral weightbearing radiograph in 20° of knee flexion. The BTP and ATT were measured using a perpendicular line drawn between the posterior position of the lateral femoral condyle and the lateral tibial plateau. PTS measurements were assessed by the anatomic tibial axis. Statistical analysis using linear regression-r > 0.6 was considered strong, r between 0.4 and 0.6 moderate, and r < 0.4 weak-and t tests were used to compare the PTS with BTP and SSD in ATT.

RESULTS

A total of 72 patients were analyzed using ACL stress radiographs. The results found a significant positive correlation between increased PTS and increased BTP for the ACL-intact knees (P < .001; r = 0.476). A significant increase was found in the SSD in ATT of 1.73 mm with a positive correlation between increased PTS and increased SSD in ATT of ACL-deficient knees (P < .001; r = 0.397). A subgroup analysis reported significant increases in SSD in ATT for both ACL-injured knees with a PTS ≥12° (P = .008) and for chronic ACL tears (P < .001) and no significant differences in SSD in ATT for ACL-injured knees with a PTS of <12° (P = .650) and for acute ACL tears (P = .745).

CONCLUSION

This study found a significant positive correlation between PTS and the BTP in ACL-intact knees and for the SSD in ATT between ACL-injured and ACL-intact knees. Moreover, the SSD in ATT was significantly increased for ACL-injured knees with a PTS of ≥12° and for chronic ACL tears. No significant difference in SSD in ATT was found for ACL-injured knees with a PTS of <12° and for acute ACL tears.

One-stage revision anterior cruciate ligament reconstruction: Preoperative evaluation, planning and surgical techniques. A review of current concepts

The increased rate of anterior cruciate ligament (ACL) tears has led to a greater number of revisions. Revision surgery can be performed in one or two stages. Single-stage revision ACL reconstruction (ssRACLR) may be performed when prior tunnels can be re-used or bypassed whereas a two-stage procedure is indicated when bone grafting of dilated tunnels prior to revision is necessary. While both approaches have shown similar functional outcomes and failure risk, ssRACLR is preferred, when possible, to avoid the increased morbidity, inconvenience and cost associated with two-stage RACLR. In adequately planning for RACLR, a surgeon should investigate the mechanism and timing of injury as well as the previous graft selection, associated pathology and the tunnel placement and size. It is especially important to obtain radiographs and three-dimensional imaging including magnetic resonance imaging (MRI) and computed tomography (CT), which allow the surgeon to accurately evaluate the entire tunnel architecture to determine surgical staging. Following a detailed assessment of the pathoanatomy, the surgeon may determine graft and hardware type, tunnel placement and utilization of lateral extra-articular tenodesis (LET) and other procedures. In our experience, ssRACLR can be carried out for over 90% of revision cases with creative pre-operative planning using autograft with bone plug(s), divergent tunnel creation on the femur (when necessary) and convergent tunnel creation on the tibia (when appropriate) and suspensory or interference fixation as needed. In revision scenarios, we believe that autografts with bone plugs provide the best opportunity for graft healing and incorporation and that LET can be a useful adjunct to reduce re-tear rates. The purpose of this review is to report on the preoperative considerations and surgical techniques for performing ssRACLR, as well as the outcomes.

Level of Evidence

Level V expert opinion.

Outcomes of All-Inside Arthroscopic ACL Reconstruction with Lateral Extra-Articular Tenodesis (ACLR + LET)

Background

Anatomic single-bundle ACL reconstruction (ACLR) produces good results when the graft and tunnel are positioned in the anatomic footprint on the femoral and tibial insertion sites in a more oblique orientation. The Anterolateral Complex of the knee and its biomechanical role in controlling rotational laxity, internal rotation, and pivot shift has led to adding adjunctive procedures like extra-articular augmentation and lateral extra-articular tenodesis (LET) to decrease rotational laxity. We prospectively analyzed young adults with rotational instability and generalized laxity undergoing an arthroscopic single bundle ACLR with an additional LET procedure.

Methods

42 patients, aged between 20 and 50, undergoing all-inside ACLR augmented with concomitant lateral extra-articular tenodesis between November 2020 and October 2021 were included. All patients were followed up for one year and functional assessment comprised of the International Knee Documentation Committee [IKDC] score, visual analogue score [VAS], and Lysholm Knee Scoring Scale at 6 months and 1 year. Return to activity was assessed using the Tegner Activity Score.

Results

The Lysholm score, IKDC score, and VAS showed significant improvements at 6 months after ACLR + LET (p < 0.0001) and further improved significantly at 1 year. The patients had a significant decline in the Tegner Activity Scale at 6 months but returned to the near pre-injury level (5.98 ± 0.924) at 1 year (5.67 ± 0.816) which was insignificant (p = 0.1067). Three patients sustained mild complications. 93% were satisfied with the surgery, 66% returned to sports and no patient underwent re-operation.

Conclusions

Combination of LET with ACLR produces good functional outcomes, high rates of return to sports activities, and no graft failure in young patients at high risk of failure.

Non-Anatomic Reconstruction in Multiligament Knee Injuries: A Functional Approach

Background/Objectives: Multiligament knee injuries, involving damage to multiple stabilizing structures, present a significant challenge in orthopedic surgery, often resulting in knee instability and compromised function. While anatomic ligament reconstruction has been traditionally advocated, non-anatomic techniques may provide effective alternatives, particularly for patients with moderate functional demands who do not require high-level athletic performance. Material and methods: In this study, we assessed the outcomes of a non-anatomic, hybrid surgical approach involving combined arthroscopic and open non-anatomic ligament reconstruction in 60 patients with multiligament knee injuries. Using simplified reconstruction methods for the medial collateral ligament (MCL) and lateral collateral ligament (LCL), we tailored the procedures to the needs of active, non-professional patients. Functional outcomes were evaluated using the International Knee Documentation Committee (IKDC) Questionnaire, Lysholm Knee Scoring Scale, and Knee Injury and Osteoarthritis Outcome Score (KOOS). Results: Postoperative improvements were significant, with the total IKDC score increasing from a median of 39.1 preoperatively to 75.9 postoperatively, Lysholm from 61.0 to 87.0, and KOOS from 47.6 to 85.7 (p < 0.01). The results demonstrated significant improvements across all scoring systems, with enhanced knee stability, reduced pain, and better quality of life. Conclusions: These findings support the feasibility of non-anatomic reconstructions as a practical solution for patients seeking a return to daily activities and recreational sports without the complexity of full anatomic reconstruction.

Trends in lateral extra-articular augmentation use and surgical technique with anterior cruciate ligament reconstruction from 2016 to 2023, an ACL study group survey

PURPOSE

To survey the ACL study group (ACLSG) members to determine the current practice patterns surrounding the use and methodology of lateral extra-articular procedures (LEAPs), including anterolateral ligament reconstruction (ALLR) or lateral extra-articular tenodesis (LET) during ACL reconstruction (ACLR).

METHODS

A web-based questionnaire was distributed to members of the ACLSG during the 2016, 2018, 2020, and 2023 biennial meetings. Questions explored the indications and techniques when incorporating LEAPs in ACLR.

RESULTS

Analysis of survey responses found that the reported use of LEAPs in both primary and revision ACLR increased between 2016 and 2023 and that surgeons were using lateral augmentation more frequently over time. Surgical techniques were stable across survey years, with most surgeons using iliotibial band (ITB) autograft attached at Gerdy's tubercle, passed under the lateral collateral ligament (LCL), and anchored proximal/posterior to the lateral femoral epicondyle.

CONCLUSION

Survey responses demonstrate that LEAPs are becoming more common among ACL surgeons in the ACL SG, with the modified Lemaire LET being the predominant technique. This aligns with recent clinical studies showing improved outcomes and reduced risk of failure in ACLR with lateral augmentation compared to ACLR alone.

LEVEL OF EVIDENCE

Level V, Expert Opinion.

Functional Outcomes and Return to Sport of Combined ACL Reconstruction and Lateral Extra-Articular Tenodesis in High-Pivot Kabbadi Players: A Prospective Cohort Study of 93 Elite Players

Introduction

Our understanding of antero-lateral rotatory instability (ALRI) has evolved considerably, with a shift towards a combined procedure of ACL reconstruction and lateral extra-articular procedure (LEAP) to reduce ALRI and decrease graft re-rupture rates. Despite mounting evidence for the same in high-pivot and high-contact athletes in the West, there is a paucity of data for regional sports such as kabbadi. To the authors best knowledge, this is the first such study to track the outcomes of the combined procedure (ACLR and LEAP) in kabbadi players.

Methods

Ethics approval was obtained from the institutional ethics review committee. A total of 93 consecutive kabbadi players with ALRI were recruited for undergoing the combined procedure of ACLR with lateral extra-articular tenodesis. Demographical variables (age and gender) and functional outcome scores (IKDC, Lysholm, VAS, AOFAS, and FADI) were recorded pre-operatively and followed up at 6 week, 3 month, 6 month and 1 year post-surgery. In addition, complications (pain, stiffness, residual laxity, re-rupture, and infection) and return to sport were recorded.

Results

All 93 patients completed the prospective cohort study with no drop-outs. The mean age of the study population was 22.4 ± 2.7 years and 84% were males. VAS, IKDC and Lysholm scores showed significant improvement at each time frame during the study period and significant improvement at end of the study period versus baseline. AOFAS and FADI scores showed no significant difference between baseline and end of study period. There was no significant difference with respect to age and gender for knee (IKDC and Lysholm) or ankle (AOFAS and FADI) scores. Return to sport was achieved in 99% of study participants with return to pre-injury level was 86%. Re-rupture rate was low (n = 2 patients) and the majority of complications related to the LET (either a complaint of swelling or shape change phenomenon).

Conclusion

The present study shows that ACLR with LET provides a safe and effective option for treating kabbadi players engaged in an inherently high-pivot and high-contact sport. Knee outcomes (VAS, IKDC and Lysholm scores) showed substantial improvement versus baseline with a high degree of return to sport at pre-injury level and low re-rupture rate.

Combined AMRI and ALRI of the Knee in Elite Kabaddi Players: A Prospective Cohort Study of 26 Players

Introduction

ACL tears are the most common injuries in kabaddi, an inherently violent high pivoting and high-velocity direct contact sport. Combined ACL and MCL injuries and combined ACL and ALL injuries have been better understood but there is a lacuna of literature on these combined injuries in kabaddi players and no literature on combined AMRI and ALRI injuries. The present prospective cohort study aims to assess knee outcomes and return to sport for these injuries in elite kabaddi players.

Methods

A prospective cohort of 26 elite kabaddi players with clinical and MRI findings of ACL and MCL high-grade partial or complete tears were recruited. After ACL reconstruction and MCL repair, the resultant pivot shift was assessed against the now intact medial pillar and those with high-grade or explosive pivot were addressed using a modified deep Lemaire lateral extra-articular tenodesis. Pain scores (VAS) and knee outcomes (IKDC and Lysholm scores) were assessed pre-operatively and at regular intervals until 1-year follow-up. Return to sport and complications were also assessed.

Results

There was significant improvement in pain and knee scores throughout the study period, with most patients achieving full scores by six months duration. Return to sport was 96% and return to sport at pre-injury level was 77%. Complication rate of the combined triple procedure was low (< 5%), with most complications being minor.

Conclusion

The triple procedure of ACL reconstruction, MCL repair and Lateral extraarticular tenodesis successfully addressed the combined AMRI and ALRI in elite kabaddi players with a high rate of return to sport, excellent knee outcomes and low complication rate.

Supplementary Information

The online version contains supplementary material available at 10.1007/s43465-024-01268-3.

Meniscal allograft transplantation (MAT) combined with revision ACL reconstruction and lateral extra-articular tenodesis results in significantly improved outcomes, but patient-reported knee function is inferior compared to an isolated MAT

PURPOSE

Meniscal allograft transplantation (MAT) is a valuable option for postmeniscectomy syndrome in young and active patients, which can successfully improve symptoms, function and quality of life. This study aimed to report outcomes and complications in patients treated with isolated MAT or MAT combined with revision anterior cruciate ligament reconstruction (ACLR) and lateral extra-articular tenodesis (LET).

METHODS

In total, 18 patients who were treated with MAT using a soft tissue fixation technique were retrospectively analysed. Patients were allocated into two groups, the isolated MAT group and the MAT plus revision ACLR + LET group (MAT+ group). Both groups were assessed using the following Patient-Reported Outcome Measures (PROMs): Knee Injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee (IKDC), Tegner Activity Scale, Lysholm score, EuroQol 5-Dimension 5-level (EQ-5D-5L) questionnaire and a patient acceptable symptom state (PASS) statement.

RESULTS

The mean follow-up was 3.2 years and the mean age of patients was 29 (±7.6) years. Ten patients were treated with isolated MAT and eight patients were treated with MAT combined with revision ACLR and LET. No complications and no reoperations were reported. In both groups, all PROMs significantly improved postoperatively (p < 0.05), except for the Tegner score in the MAT+ group, which did not reach statistical significance (not significant [n.s.]). No significant difference was found postoperatively in PROMs between the MAT and the MAT+ group; however, differences in the KOOS Symptoms, Sports and Quality-of-life subscales reached the minimal clinically important threshold. Mean values were: IKDC 61.2 (±13.9) versus 64.7 (±23.2), KOOS Total 72.8 (±14.9) versus 68.0 (±16.7), Lysholm score 83.2 (±11) versus 84.2 (±8.7) and EQ-5D-5L 71.8 (±14.9) versus 72.2 (±22.4). Median values for the Tegner Activity Scale were 4 versus 3. PASS statement was negative in 37.5% of the MAT+ group in comparison to 20% of the MAT group (n.s.).

CONCLUSION

In terms of patient-reported outcomes, MAT is an effective and safe procedure, even when combined with revision ACLR + LET. Compared to the preoperative assessment, a significant improvement of the postoperative PROMs can be expected either when MAT is performed isolated or in combination with ACLR + LET. However, clinically important differences between the two groups can be noted in favour of the isolated MAT procedure, especially regarding symptoms and sporting activity.

LEVEL OF EVIDENCE

Level III.

Lateral extra-articular tenodesis does not enhance ACL graft healing, however, does reduce graft tunnel widening

PURPOSE

The study hypothesized that the addition of lateral extra-articular tenodesis (LEAT) in anterior cruciate ligament reconstruction (ACLR) had a significant effect on ACL graft healing.

METHODS

A total of 80 patients were divided into two cohorts matched for gender, age, body mass index, time from surgery to post-operative MRI and graft diameter. Forty patients underwent ACL reconstruction alone, while 40 underwent ACLR in addition to LEAT. Patients underwent a magnetic resonance imaging scan at 12 months post-surgery; tunnel apertures were measured using multiplanar reformation, graft healing was assessed using signal-to-noise quotient (SNQ) in three regions of interest and finally graft maturity and integration were classified using the Howell and Ge scale, respectively. In addition, clinical evaluation and patient-reported outcome measures were collected.

RESULTS

The mean femoral tunnel widening at 12 months post-surgery was 39.8 ± 14.0% in the ACLR + LEAT group and 55.2 ± 12.7% in the ACLR alone group (p < 0.05). The mean tibial tunnel widening was 29.3 ± 12.7% in the ACLR + LEAT group and 44.4 ± 12.1% in the ACLR group (p < 0.05). The mean adjusted graft SNQ was 9.0 ± 14.9 in the ACLR + LEAT group and 9.5 ± 11.4 in the ACLR group (n.s.).

CONCLUSION

At 1 year post-operatively, we noted significantly less femoral and tibial tunnel widening in the ACLR + LEAT group. LEAT did not result in a statistically significant effect on graft healing.

LEVEL OF EVIDENCE

Level III.

Synthetic Grafts in Anterior Cruciate Ligament Reconstruction Surgery in Professional Female Handball Players-A Viable Option?

Anterior cruciate ligament (ACR) rupture is a frequent injury in professional sports players. We conducted a retrospective cohort study, including 41 professional female handball players, undergoing ACR reconstruction surgery, using a Ligament Advanced Reinforcement System (LARS) graft (n = 12) or a Soft Tissue (ST) graft (n = 29). After return-to-play, the patients were asked to take a survey, reporting subjective and objective performance indexes before the injury and after return-to-play. Time from surgery to first practice and to return-to-play were significantly shorter in the LARS group (3.92 ± 1.14 vs. 6.93 ± 2.19 months, p < 0.001 and 4.71 ± 1.2 vs. 8.81 ± 2.9, respectively). While there was no difference between postoperative mean time on court, number of goals/match, number of matches played at 6 months return-to-play and 50 m, 100 m and gate-to-gate sprint times, there was a significantly greater increase in preoperative times in the ST group than in the LARS group (1.45 ± 1.05 s vs. 0.21 ± 0.58 s slower than preoperatively, p < 0.001 for 50 m; 1.09 ± 0.95 s vs. 0.08 ± 1 s, p = 0.01 for 100 m; 1.66 ± 1 s vs. 0.21 ± 0.66 s for gate-to-gate). In conclusion, LARS grafts provide a faster recovery time and better functional outcome, significantly impacting the performance of professional handball players.

Quadriceps tendon versus hamstring tendon graft for primary anterior cruciate ligament reconstruction: A systematic review and meta-analysis of randomised trials

BACKGROUND

Anterior cruciate ligament reconstruction (ACLR) is most commonly performed with hamstring tendon (HT) or bone-patellar tendon-bone (BTB) autografts, although the quadriceps tendon (QT) autograft has recently increased in popularity. This systematic review and meta-analysis review compares QT and HT autografts for primary ACLR with a sole focus on randomised controlled trials (RCTs).

METHODS

A prospective protocol was registered on PROSPERO (CRD42023427339). The search included MEDLINE, Embase and Web of Science until February 2024. Only comparative RCTs were included. The primary outcome was the International Knee Documentation Committee (IKDC) Subjective Knee Evaluation Form score. Secondary outcomes included: other validated patient-reported outcome measures (PROMs), objective strength scores, complications, and return to sport and work.

RESULTS

From 2,609 articles identified, seven were included (n = 474 patients). This meta-analysis did not identify a significant difference in post-operative IKDC scores (5 articles; p = 0.73), Lysholm scores (3 studies; p = 0.80) or Tegner activity scales (2 studies; p = 0.98). There were no differences in graft failure rates (4 studies; p = 0.92) or in overall adverse events (4 studies; p = 0.83) at 24 months post-ACLR as per meta-analysis. Donor site morbidity scores were significantly lower in the QT group (MD -4.67, 95% CI -9.29 to -0.05; 2 studies, 211 patients; p = 0.05, I2 = 34%).

CONCLUSION

There were no differences between QT and HT in PROMs, graft failure rates or overall complications based on low- to moderate-quality evidence. There may possibly be lower donor site morbidity with the QT autograft, however, the evidence is not sufficient to draw definitive conclusions.

Revision ACL reconstruction in female athletes: current concepts

The challenge of revision anterior cruciate ligament (ACL) reconstruction lies in its complexity, varied presentation, and technical intricacies. A successful ACL reconstruction should allow patients to safely return to preinjury activities. However, it is only sometimes simple, and many risk factors and concurrent pathologies come into play. Evaluating and analysing the cause of failure and associated conditions is paramount to addressing them effectively. Despite a plethora of research and improvements in knowledge and technology, e gaps exist in issues such as optimal techniques of revision surgery, graft options, fixation, concurrent procedures, rehabilitation and protocol for return to sports of high-level athletes. Female athletes need additional focus since they are at higher risk of re-injury, suboptimal clinical outcomes, and lower rates of return to sport following revision reconstruction. Our understanding about injury prevention and the protection of ACL grafts in female athletes needs to be improved. This review focuses on the current state of revision ACL surgery in female athletes and provides recommendations and future directions for optimising outcomes in this high-risk group.

Effect of Lateral Extra-Articular Procedures Combined With ACL Reconstruction on the Rate of Graft Rupture in Patients Aged Older Than 30 Years: A Matched-Pair Analysis of 1102 Patients From the SANTI Study Group

BACKGROUND

Clinical studies have demonstrated significant advantages of combined anterior cruciate ligament (ACL) reconstruction (ACLR) and lateral extra-articular procedures (LEAPs) over isolated ACLR in terms of reducing graft rupture and reoperation rates. However, most of the published studies have included young patients, and no studies have focused on patients aged >30 years.

PURPOSE/HYPOTHESIS

The purpose of this study was to compare the outcomes of isolated ACLR versus ACLR + LEAP at midterm follow-up in patients aged >30 years. The hypothesis was that patients who underwent combined procedures would experience significantly lower rates of graft rupture.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients >30 years of age who underwent primary ACLR + LEAP between January 2003 and December 2020 were propensity matched at a 1:1 ratio to patients who underwent isolated ACLR. A retrospective analysis of prospectively collected data was performed to determine graft rupture rates, knee stability, reoperation rates, and complications. Graft survivorship was assessed using the Kaplan-Meier method. Risk factors associated with the occurrence of graft failure were analyzed using a Cox proportional hazards model.

RESULTS

Two groups of 551 patients each were included in the study, and the mean follow-up was 97.19 ± 47.23 months. The overall mean age was 37.01 ± 6.24 years. The LEAP group consisted of 503 (91.3%) patients who had anterolateral ligament reconstruction and 48 (8.7%) patients who had a Lemaire procedure. Overall, 19 (1.7%) patients had graft failure: 15 (2.7%) in the no-LEAP group and 4 (0.7%) in the LEAP group (P = .0116). The risk of graft failure was significantly associated with the absence of LEAP (31 vs 12; hazard ratio, 3.309; 95% CI, 1.088-10.065; P = .0350) and age between 30 and 35 years (hazard ratio, 4.533; 95% CI, 1.484-13.841; P = .0080). A higher rate of reoperation for secondary meniscectomy was found in the no-LEAP group (5.6% vs 2.2%; P = .0031).

CONCLUSION

Patients aged >30 years who underwent combined ACLR and LEAP experienced a >3-fold lower risk of ACL graft failure compared with those who underwent isolated ACLR. Furthermore, the group without LEAP experienced a higher rate of secondary meniscectomy.

Digital measurement of anterolateral knee laxity using strain sensors

PURPOSE

The ambition of the research group was to develop a sensor-based system that allowed the transfer of results with strain sensors applied to the knee joint. This system was to be validated in comparison to the current static mechanical measurement system. For this purpose, the internal rotation laxity of the knee joint was measured, as it is relevant for anterolateral knee laxity and anterior cruciate ligament (ACL) injury.

METHODS

This is a noninvasive measurement method using strain sensors which are applied to the skin in the course of the anterolateral ligament. The subjects were placed in supine position. First the left and then the right leg were clinically examined sequentially and documented by means of an examination form. 11 subjects aged 21 to 45 years, 5 women and 6 men were examined. Internal rotation of the lower leg was performed with a torque of 2 Nm at a knee flexion angle of 30°.

RESULTS

Comparison of correlation between length change and internal knee rotation angle showed a strong positive correlation (r = 1, p < 0.01). Whereas females showed a significant higher laxity vs. males (p = 0.003).

CONCLUSIONS

The present study showed that the capacitive strain sensors can be used for reproducible measurement of anterolateral knee laxity. In contrast to the previous static systems, a dynamic measurement will be possible by this method in the future.

Reconstruction of the anterior cruciate ligament: a historical view

Management of anterior cruciate ligament (ACL) tears has continuously evolved since its first description in approximately 170 A.D. by Claudius Galenus of Pergamum and Rome. The initial immobilization using casts was replaced by a variety of surgical and conservative approaches over the past centuries. The first successful case of ACL repair was conducted by Mayo Robson in 1885, suturing cruciate at the femoral site. In the nineteenth century, surgical techniques were focused on restoring knee kinematics and published the first ACL repair. The use of grafts for ACL reconstruction was introduced in 1917 but gained popularity in the late 1900s. The introduction of arthroscopy in the 1980s represented the greatest milestones in the development of ACL surgery, along with the refinements of indications, development of modern strategies, and improvement in rehabilitation methods. Despite the rapid development and multitude of new treatment approaches for ACL injuries in the last 20 years, autografting has remained the treatment of choice. Compared to the initial methods, arthroscopic procedures are mainly performed, and more resistant and safer fixation devices are available. This results in significantly less trauma from the surgery and more satisfactory long-term results. The most commonly used procedures are still patellar tendon or hamstring autograft. Additionally, popular, but less common, is the use of quadriceps tendon (QT) grafts and allografts. In parallel with surgical developments, biological reconstruction focusing on the preservation of ACL remnants through the use of cell culture techniques, partial reconstruction, tissue engineering, and gene therapy has gained popularity. In 2013, Claes reported the discovery of a new ligament [anterolateral ligament (ALL)] in the knee that could completely change the treatment of knee injuries. The intent of these modifications is to significantly improve the primary restriction of rotational laxity of the knee after ACL injury. Kinematic studies have demonstrated that anatomic ACL reconstruction and anterolateral reconstruction are synergistic in controlling pivot displacement. Recently, there has been an increased focus on the application of artificial intelligence and machine learning to improve predictive capability within numerous sectors of medicine, including orthopedic surgery.