Anterolateral Ligament Expert Group consensus paper on the management of internal rotation and instability of the anterior cruciate ligament - deficient knee

Mapping the anterolateral ligament of the knee: a bibliometric analysis

BACKGROUND

This study aims to evaluate research trends, key contributors, and thematic focuses in research of the anterolateral ligament (ALL) of the knee. It seeks to identify future direction for studies related to long-term clinical outcomes regarding ALL's role in rotational stability, especially in the context of anterior cruciate ligament (ACL) injuries.

METHODS

A bibliometric analysis was conducted using the Web of Science (WoS) database, covering publications from 2012 to 2024 with the search term "anterolateral ligament". A total of 942 studies were identified. Descriptive statistics summarized publication trends, authorship, institutional contributions, and citation metrics. VOSviewer software was used to analyze co-authorship network analysis, keyword co-occurrence mapping, and total citation analysis. Yearly publication and citation trends were analyzed using WoS data. Studies addressing the ALL in other body regions were excluded. Additionally, only authors with at least one publication and one citation were considered, and documents with more than 25 authors were excluded. A total citation analysis was conducted, and 24 relevant keywords with more than 5 occurrences were identified using VOSviewer.

RESULTS

Among 942 publications, 707 were original articles. Research output peaked in 2017 (125 articles). Sonnery-Cottet was the leading author (75 publications), while Universidade De São-Paulo emerged as the top institution (57 publications). Key journals included Arthroscopy: Journal of Arthroscopic and Related Surgery (143 articles) and The American Journal of Sports Medicine (131 articles). Keywords such as "anterior cruciate ligament", "reconstruction", and "rotational stability" dominated, reflecting a focus on ACL injury management. The top ten cited studies accrued 3,86 citations, with Claes et al.'s anatomical study leading (621 citations). Of the 942 ALL-related articles in WoS, 381 focused on anatomy (11,278 citations) while 814 addressed reconstruction (17,048 citations). Keyword trends shifted from anatomical to clinical terms, with anatomy declining and stability, injury, and outcomes gaining prominence from 2021 to 2024.

CONCLUSIONS

This bibliometric analysis underscores the growing interest in ALL research, peaking between 2016 and 2017. While foundational studies on ALL anatomy and biomechanics appear saturated, future research should prioritize clinical outcomes in terms of failure rate, reoperation, the long-term efficacy of ACL-ALL reconstruction, and advancements in imaging techniques.

What Is the Anatomic Footprint of the Anterolateral Ligament of the Knee? A Race- and Sex-based MRI Analysis

BACKGROUND

The anatomic location of the anterolateral ligament (ALL) of the knee is critical to ALL reconstruction, but there is not a clear consensus about the location of its footprint. Knowledge of the anatomic footprint is necessary to assess intraoperative positioning and postoperative functional outcomes of ALL reconstruction. Furthermore, while racial and sex-related variations in the ACL have been well documented, it remains unknown whether such differences extend to the ALL, as well as whether these differences influence surgical strategies.

QUESTIONS/PURPOSES

We generated three-dimensional (3D) models based on MRI scans to (1) describe the differences in the ALL position between Chinese and White patient groups by establishing its anatomic footprint relative to adjacent anatomic structures, (2) assess the length of the ALL and the correlation between the ALL sagittal plane orientation and the position of its footprints, and (3) simulate the risk of injury to the lateral collateral ligament (LCL) while reconstructing the ALL by the use of drills of various diameters.

METHODS

In our institution, patients' information was systematically gathered through a prospective database framework. Participants independently provided demographic details via a structured survey questionnaire, which were then recorded by our team of well-trained researchers. The collected data encompassed age, sex (female and male), ethnic background (White and Chinese), height (centimeters), weight (kilograms), and BMI (kg/m2). This study involved 120 volunteers, including 60 Chinese and 60 age-, sex-, and BMI-matched White participants, whose normal knees were scanned with MRI to generate 3D models. ALL femoral and tibial footprints were identified and digitally delineated on MRI images by two board-certified orthopaedic surgeons. Subsequently, the locations of the ALL femoral and tibial footprints were identified in relation to adjacent anatomic structures. The length of the ALL from the femoral footprint to tibial footprint was then measured, together with the angle formed by the ALL in the sagittal plane relative to a line parallel to the anatomic axis of the femur. Through regression analysis, we explored the correlation between the sagittal orientation of the ALL and the position of the footprint. Finally, simulations of ALL femoral tunnel drilling were performed to assess damage to the LCL footprint center caused by the use of drills of varying diameter.

RESULTS

The ALL femoral footprint was adjacent to both the lateral epicondyle and the LCL, positioned anterior and distal to the LCL attachment, while the ALL tibial footprint was located between the Gerdy tubercle and the fibular head. The mean ± SD femoral footprint of the ALL in the Chinese population was more distal and anterior compared with the White population, which was located posterior to the lateral epicondyle (4 ± 2 mm versus 5 ± 2 mm, mean difference 1 [95% confidence interval (CI) 0 to 2]; normalized p value = 0.03) and distal to the lateral epicondyle (8 ± 3 mm versus 6 ± 2 mm, mean difference 2 [95% CI 1 to 2]; normalized p value = 0.005). There were differences between Chinese patients and White patients at ALL tibial footprint locations, where the distance from the fibular head was 21 ± 3 mm versus 22 ± 4 mm (mean difference 1 [95% CI 0 to 2]; normalized p value = 0.02), and the distance from the lateral tibial plateau was 7 ± 1 mm versus 8 ± 2 mm (mean difference 1 [95% CI 0 to 1]; normalized p value = 0.004). The ALL length was longer in White patients than in Chinese patients (33 ± 4 mm versus 29 ± 3 mm, mean difference 4 [95% CI 3 to 5]; normalized p < 0.001). Multiple linear relationships were observed between the ALL sagittal plane angle and the normalized locations of the ALL femoral and tibial footprints (R = 0.32, mostly correlated). In the posterior directions relative to the lateral epicondyle, the femoral footprint location exhibited an effect on the sagittal angle (p = 0.001). With every 4 mm of posterior movement of the ALL femoral footprint relative to the lateral epicondyle, the sagittal plane angle decreases by about 3.2°. Based on the distance between the ALL and LCL, when simulating femoral tunnel drilling using drill diameters > 8 mm in the Chinese group and > 7 mm in the White group, the LCL footprint center would be substantially damaged in more than one-half of the patients.

CONCLUSION

Minor differences were observed in the ALL footprints between Chinese and White populations, although no sex-related variations were found. These race-specific discrepancies highlight the need for personalized surgical approaches. In tunnel positioning, the ALL femoral footprint in Chinese populations was located more distal and anterior relative to the lateral epicondyle compared with the White populations. Regarding graft length, White individuals exhibited longer ALL dimensions than Chinese individuals, necessitating prioritization of longer grafts. For graft diameter, in the White group, the ALL footprint distance to the LCL footprint was closer compared with the Chinese group, indicating higher risks of LCL injury during ALL reconstruction. Notably, a linear association existed between the ALL sagittal angle and femoral footprint, offering quantitative guidance for intraoperative precision.

CLINICAL RELEVANCE

For patients with ALL injuries of the knee or revision surgeries where the native footprint cannot be identified, 3D MRI reconstruction technology enables precise 3D reconstruction of the ALL footprint using anatomic landmarks from the healthy side. This provides surgeons with effective preoperative planning guidance, intraoperative navigation support, and postoperative clinical function assessment. The established relationship between ligament sagittal angles and footprint positioning assists in real-time intraoperative evaluation of tunnel placement and postoperative accuracy verification. Additionally, our data revealed that the distance between the ALL footprint and LCL footprint was shorter in the White group compared with the Chinese group. Based on this anatomic variation, it is recommended to set the upper limit of ALL femoral tunnel diameter at 8 mm for the Chinese group and 7 mm for the White group. Further biomechanical studies are required to precisely define the safety threshold for graft diameter, ensuring graft stability while minimizing the risk of iatrogenic LCL injury.

Imaging Review of Knee Ligament Reconstructions Other than the Anterior Cruciate Ligament

Assessment of knee ligament reconstructions other than the anterior cruciate ligament is challenging due to limited data and continuously developing techniques. Imaging is vital to assessment, demonstrating expected postoperative findings, allowing detection of complications, and enabling differentiation of techniques from one another-information that is critical if revision is being contemplated. Stress radiography is useful for evaluating joint stability in the setting of ligament insufficiency. The three-dimensional and multiplanar reconstruction capabilities of CT are highly useful in multiligament reconstruction, allowing unhindered evaluation of the many intersecting bone tunnels. Susceptibility artifacts in MRI can be remedied by use of metal artifact reduction sequences. Each technique, graft, and choice of specific ligaments to reconstruct must be decided on a case-to-case basis. Anatomic reconstruction reproduces the native ligament's anatomy but is more technically complex. Nonanatomic reconstruction is easier to perform but potentially provides less stability. As for graft selection, an autograft weakens another knee stabilizer, but an allograft is more expensive and less readily available. The decision to perform a single-ligament versus combined-ligament reconstruction ultimately rests on the degree of instability and the desire to return to sport. In contrast to single-ligament reconstruction, combined-ligament procedures are at higher risk of postoperative stiffness, arthrofibrosis, and tunnel convergence. Renewed attention to repair along with improvements in patient selection and rehabilitation protocols may change the future of operative treatment of ligament injury, and along with it, radiologic appraisal and reporting. ©RSNA, 2025 Supplemental material is available for this article.

Recovery of Full Hyperextension After Anterior Cruciate Ligament Reconstruction Is Associated With Better Functional Outcomes but Greater Anterior Cruciate Ligament-Related Laxity After a Minimum 24-Month Follow-Up

PURPOSE

To evaluate patients who had anterior cruciate ligament (ACL) reconstruction with preoperative hyperextension and compare physical examination (KT-1000 and pivot shift) and patient-reported outcome measures of patients who recovered the entire hyperextension with patients who did not.

METHODS

Patients aged 18 to 60 years with more than 5° of knee hyperextension who had anatomic ACL reconstruction with any graft from June 2013 to June 2021 and at least a 24-month follow-up were evaluated retrospectively. Hamstrings and patellar tendon grafts were fixed around 20° to 30° of flexion and in full extension, respectively. Patients who could recover hyperextension were compared with patients who did not. Preoperative, intraoperative, and postoperative data, including physical examination and patient-reported outcome measures, were evaluated.

RESULTS

Of the 225 patients evaluated, 48 (21.3%) did not recover hyperextension, and 177 recovered full range of motion. Patients who did not recover hyperextension had a larger graft diameter (8.7 ± 0.7 mm [confidence interval, 8.502-8.898 mm] vs 8.3 ± 0.7 mm [confidence interval, 8.197-8.403 mm]; P = .018). Regarding the postoperative subjective variables, patients who recovered hyperextension showed improvement on all scales (International Knee Documentation Committee, Lysholm, Forgotten Joint Score, and Global Perceived Effect) evaluated compared with patients who did not recover the range of motion. Patients who recovered hyperextension also showed more laxity on physical examination, measured by the KT-1000 (1.8 ± 0.8 vs 1.1 ± 1.0; P = .0006) and the pivot shift (62.1% [grade 0] and 37.9% [grade 1] vs 79.2% [grade 0] and 20.8% [grade 1]; P = .027).

CONCLUSIONS

Patients with knee hyperextension who regained range of motion after ACL reconstruction have worse knee laxity than patients who regained full extension but not hyperextension. However, patients who recover full range of motion showed higher scores on subjective function scales, including a greater number of patients who achieved patient acceptable symptom state for the International Knee Documentation Committee score.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic trial.

Structural Adaptations of the Anterolateral Complex of the Knee and Associated Tissues: A Comparative Anatomical and Histological Analysis of Knees With and Without an Anterolateral Ligament

The anterolateral ligament (ALL) is considered a secondary stabilizer of internal rotation and, due to proximity to the lateral collateral ligament (LCL), it may contribute to anterolateral rotatory stability. This study characterized the anatomy of the ALL and associated tissues of the anterolateral complex (ALC) to determine if structural and histological compensatory adaptations exist in patients without an ALL. Forty-nine cadaveric knees were dissected from distal-to-proximal using established landmarks with the aid of internal rotation stress to localize the ALL (if present), LCL, iliotibial band (ITB), and anterolateral capsule. The width and thickness of ALL and LCL were measured with digital calipers at the origin, middle, and insertion, and cross-sectional areas were calculated. ALL and LCL length and ITB thickness were also obtained. Samples of each tissue were stained with hematoxylin and eosin and picrosirius red, and histological images were evaluated with ImageJ to quantify collagen density (mean gray value [mgv]) and quantity (percent coverage). Size measurements and collagen characteristics were compared between ALL-present and ALL-deficient knees. The ALL was identified in 63% of knees with mean cross-sectional areas of 8.9, 5.8, and 9.7 mm2 at the origin, middle, and insertion, respectively. Mean collagen density of the ALL was 106.9 mgv on a scale of 0 (black) to 255 (white), and overall collagen quantity was 40.3%. Proximal LCL width (p = 0.04), distal LCL thickness (p = 0.03), and cross-sectional area (p = 0.01), and ITB thickness (p = 0.02) were significantly greater in ALL-deficient knees. A significantly higher collagen density was found within the LCL (p = 0.04), and higher overall quantity of collagen within the LCL (p < 0.01) and ITB (p < 0.01), of ALL-deficient knees. Gross anatomical and histological alterations exist in knees without an ALL compared with those with an ALL. These may reflect adaptations in the ALC and LCL that are present to compensate for the absence of the anterolateral rotatory stability afforded by the ALL.

Optimal Anterolateral Ligament Tibial Tunnel Orientation to Prevent ACL Tunnel Collision and Saphenous Nerve Injury

Background

Collision risks between femoral tunnels during combined anterior cruciate ligament (ACL) and anterolateral ligament (ALL) reconstruction have been reported. However, studies on collision risks between tibial tunnels and optimal ALL tibial tunnel orientation are lacking.

Purpose

To analyze the optimal orientation of the ALL tibial tunnel to minimize collisions with the ACL tibial tunnel while preventing injury to the saphenous nerve in combined reconstruction.

Study Design

Descriptive laboratory study.

Methods

Preoperative magnetic resonance imaging (MRI) and postoperative computed tomography (CT) images of patients who underwent primary ACL reconstruction using the anteromedial portal technique were analyzed. Only patients with preoperative MRI scans including thin-cut images (<1 mm) were included for 3-dimensional (3D) reconstruction. Patients who underwent ALL reconstruction or had poorly 3D-reconstructed essential structures were excluded to ensure accurate reproduction of bony attachments and landmarks associated with ALL. Bony structures of the knee joint, including the proximal tibia with the actual ACL tibial tunnel, were reconstructed from the postoperative CT scans. The greater saphenous vein (GSV), which runs together with the saphenous nerve, was reconstructed from the preoperative MRI and subsequently transferred to the CT model, maintaining the appropriate positional relationship. Twelve orientations of the ALL tunnel (at 10° intervals, ranging from 0° to 20° anteriorly and from 0° to 30° distally) were simulated with the final 3D model, starting from the ALL tibial footprint (midpoint between the Gerdy tubercle and the fibular head, 10 mm distal to the joint line), to measure the distances between the ALL tunnel trajectory and other structures (ACL tibial tunnel, GSV) by each orientation.

Results

A total of 35 out of 304 patients were included in this study. An anteriorly oriented ALL tunnel decreased the minimum distance to the ACL tibial tunnel (MD-ACL) and increased minimum distance to the GSV (MD-GSV) (all P < .001). A distally oriented ALL tunnel increased MD-ACL and decreased MD-GSV (all P < .001). Optimal ALL tunnel orientation was 10° anterior to 30° distal (MD-ACL, 14.6 ± 4.0 mm; MD-GSV, 27.8 ± 12.4 mm) and 20° anterior to 30° distal (MD-ACL, 11.5 ± 3.6 mm; MD-GSV 43.6 ± 12.9 mm), considering both collisions with the ACL tunnel and the potential risk of injury to the saphenous nerve.

Conclusion

The optimal orientations of the ALL tibial tunnel to avoid collision with the ACL tibial tunnel and prevent saphenous nerve injury are 10° anterior to 30° distal and 20° anterior to 30° distal for far-cortex drilling techniques, starting from the midpoint between the Gerdy tubercle and the fibular head, 10 mm distal to the joint line.

When is anterolateral complex augmentation indicated? Perspectives from the 2024 Freddie Fu Panther Sports Medicine Symposium

PURPOSE

This study aimed to determine the trends and indications for anterolateral complex augmentation during anterior cruciate ligament reconstruction (ACL-R) among international orthopedic sports surgeons.

METHODS

An electronically distributed survey was sent out to international surgeons with high-volume experience in complex ligament reconstructions and revision surgery attending the 2024 Freddie Fu Panther Sports Medicine Symposium. The survey was sent prior to the meeting with questions related to the use of lateral extra-articular tenodesis (LET) or anterolateral ligament reconstruction (ALL-R) during ACL-R. Sessions pertaining to anterolateral complex augmentation were held during the symposium to inform about current clinical practices among attendees.

RESULTS

A total of 49 surgeons were identified from 5 different geographic regions prior to the meeting date and were sent an electronic survey, of which 48 responded (98% response rate). Among the surgeons who reported performing anterolateral complex augmentation procedures (n = 45), a total of 39 (87%) respondents reported using only the LET technique, 2 (4%) reported using only the ALL-R technique, and 4 (9%) reported using both techniques during ACL-R. The most common indication for anterolateral complex augmentation was a high-grade pivot shift, which 39 of 43 (91%) respondents ranked in their top 3 indications. In the setting of primary ACL-R, respondents added LET when using hamstring tendon autograft in 38% of cases on average compared with 34% of cases when using either bone-patellar tendon-bone autograft or quadriceps tendon autograft. In the setting of revision ACL-R, LET was added in an average of 68% of cases for a first-time revision ACL-R and in 84% of cases for a multiple-revision ACL-R.

CONCLUSION

The most common indication for ACL-R with anterolateral complex augmentation was a high-grade pivot shift and most respondents preferred LET over ALL-R. Respondents performed LET in a comparable percentage of cases of primary ACL-R using hamstring tendon, bone-patellar tendon-bone, and quadriceps tendon autografts, and this number increased with the number of revision ACL-Rs. Based on the results of this survey, surgeons may consider adding LET in cases of revision ACL-R or in patients with a high-grade pivot shift.

LEVEL OF EVIDENCE

Level V.

Similar outcomes between gracilis-reinforced ITB and HT with modified Lemaire technique in combined ACL reconstruction with lateral tenodesis: A propensity score-matched analysis

PURPOSE

While both iliotibial band graft augmented by gracilis tendon (ITB + G) and hamstring autograft with modified Lemaire lateral extra-articular tenodesis (STG + LET) are established techniques for addressing rotatory instability in anterior cruciate ligament reconstruction, no direct comparison exists between these approaches. The purpose of this study was to provide the first direct comparison between these two surgical techniques regarding graft survival, functional outcomes and return to sport.

METHODS

This single-centre, single-surgeon retrospective study analyzed 56 patients (28 per group) after 1:1 propensity score matching based on age, gender and Tegner activity scale. Primary end point was failure (graft retear or secondary meniscal lesion). Secondary outcomes included the International Knee Documentation Committee (IKDC), anterior cruciate ligament-return to sport after surgery (ACL-RSI) scores, and return to sport rate. Kaplan-Meier survival analysis and between-group comparisons were performed using appropriate statistical tests.

RESULTS

At mean follow-up of 53.3 ± 6.4 months, failure-free survival rates at 24 months were 85.7% (95% confidence interval [CI]: 66.3-94.4) for STG + LET and 89.3% (95% CI: 70.4-96.4) for ITB + G (p = 0.664). Graft retear rate was 7.1% (STG + LET: 3.6%, ITB + G: 10.7%). Secondary meniscal injuries occurred equally (14.3%) in both groups. Return-to-sport rate was 89.3% at mean of 9.6 ± 3.9 months. Mean IKDC scores were 87.5 ± 11.4 for STG + LET and 83.6 ± 16.3 for ITB + G, with 73.7% achieving Patient Acceptable Symptom State criteria. ACL-RSI scores were similar between groups (STG + LET: 74.2 ± 24.3 and ITB + G: 73.5 ± 26.8).

CONCLUSION

No significant differences were found between ITB + G and STG + LET techniques regarding failure rates, return to sport and functional outcomes. Both techniques achieved satisfactory results in this cohort, with similar complication profiles. This comparison provides valuable clinical guidance, supporting surgical decision-making based on surgeon experience.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

An isolated extra-articular procedure can be indicated for patients with minor instabilities and intact graft after anterior cruciate ligament reconstruction

BACKGROUND

Some patients submitted to isolated ACL reconstruction may have symptomatic postoperative rotational instability. The objective of this study was to evaluate a population with mild rotatory instability after ACL reconstruction, which was submitted to an isolated extra-articular procedure.

METHODS

Patients submitted to an isolated extra-articular procedure after ACL reconstruction were retrospectively evaluated. Only patients presenting anterior knee instability of less than 5 mm, pivot-shift of a maximum of 1+, and ACL graft intact were included. Demographic data, physical examination and subjective functional scales were evaluated.

RESULTS

Twenty patients were included. The mean age was 27.0 ± 7.3 years. The follow up time after the extra-articular procedure was 27.5 ± 6.2 months. The KT-1000 decreased from 3.0 mm ± 0.7 mm to 2 mm ± 0.4 mm (P = 0.00016). The pivot-shift improved from 100% of grade 1 positivity to 30% (6/20 patients) of grade 1 positivity (P < 0.0001). The IKDC showed no difference (74.4 ± 11.8 vs. 87.6 ± 5.8; P = 0.087), but the percentage of patients who passed the PASS IKDC cut-off value increased from 45% (9/20) to 95% (19/20) (P = 0.0012). The Lysholm increased from 81.1 ± 7.3 to 91.2 ± 5.7 (P = 0.0001).

CONCLUSIONS

Patients submitted to an isolated extra-articular procedure due to residual instability after ACL reconstruction showed improvement in physical examination (KT-1000 and pivot-shift) and subjective functional scales. This procedure can be considered for a specific population with minor instabilities and intact ACL graft, avoiding a complete ACL revision.

ACL plus ALL reconstruction restores normal knee stability and does not lead to lateral pain or signs of lateral overstrain

ACL rupture is a common injury in recreational and professional athletes. Most ACL tears occur in combination with an ALL lesion. Combined reconstruction of the ACL and ALL reduces re-rupture rates by up to 3.1 times compared to isolated ACL reconstruction using hamstring tendons; however, it has not yet been established as the surgical standard. The purpose of this study was to investigate if patients benefit from ACL+ALL reconstruction in terms of translation and rotation stability, return to activity and return to sport, as well as to assess any potential negative effects of this technique.This is a multicentric study of retrospectively collected patients who were followed up 12.7 months postoperatively. The patient sample consisted of 55 patients (group 1: n=29, Munich/Germany, ACL+ALL, femoral ALL fixation with interference screw, and group 2: n=26, Bolzano/Italy, ACL+ALL, femoral ALL-fixation with SwiveLock). Clinical outcomes were evaluated through instrumental measurements with two different devices to assess translational anteroposterior and rotational stability and through patient-reported outcome measures (Lysholm Score, Activity Rating Scale, Tegner Score, VAS (PROMs)).A total of 55 patients (mean (± SD) age: 24.7 ± 7.8 years) with a mean follow-up of 12.7 ± 1.5 months were included. The mean anterior translation of all operated (ACL+ALL) knees was 3.2 ± 1.1 mm and was not significantly different from the values of the non-operated knees (2.6 ± 1.0 mm). The results of the anterior drawer test in internal rotation were 3.3 ± 1.1 mm for the operated knee vs. 2.7 ± 1.0 mm for the non-operated knee (p=0.0014). There were no further significant differences between the operated and non-operated knee regarding translation or internal and external rotation. The mean value for pain on the lateral side of the knee was 1.1 ± 1.3 on the VAS 0-10 pain scale. All other PROMs showed no relevant differences between pre-injury and post-operative.ALL reconstruction restores the function of the anterolateral ligament of the knee. In this study, knee joint stability regarding anteroposterior translation and rotation showed values almost identical to those of the healthy non-operated contralateral knee. It leads to excellent patient outcomes with near pre-injury levels regarding the relevant PROMs. In particular, combined reconstruction did not result in any clinically significant negative side-effects such as pain on the ALL incision site or signs of overstrain in the lateral knee.

Anterior Cruciate Ligament Reconstruction Using Lateral Extra-Articular Procedures: A Systematic Review

Background and Objectives: The present systematic review investigated the efficacy of lateral extra-articular tenodesis (LET) and anterolateral ligament (ALL) as lateral extra-articular procedures (LEAPs) for anterior cruciate ligament (ACL) reconstruction. ACL reconstruction using LEAP may reduce graft rupture and rotatory laxity and allow a quicker return to sports. The outcomes of interest were patient-reported outcome measures (PROMs), return to sport, laxity, failure rate, and safety profile. Materials and Methods: The present systematic review followed the 2020 PRISMA guidelines. In December 2024, PubMed, EMBASE, and Web of Science were accessed without constraints. All clinical investigations evaluating LEAP for ACL reconstruction were considered. Only studies that considered LET and ALL as LEAP were considered. Only studies using a hamstring tendon autograft associated with LET or ALL were considered. Results: Data from 27 clinical studies (3423 patients) were retrieved. The mean length of follow-up was 61.8 ± 39.5 months. ACL reconstruction using LEAP led to a statistically significant improvement in the Lysholm score (p < 0.01) and IKDC (p < 0.01). The mean joint laxity, as measured by the arthrometer, was 1.5 ± 1.8 mm. Finally, 72.3% (623 of 668) of patients returned to their pre-injury level of sport at a mean of 6.3 ± 4.4 months. At the last follow-up, the LET group showed greater IKDC (p = 0.04). On the other hand, there was a statistically significant greater rate of patients positive to the Lachman test (p < 0.01), return to sport (p < 0.01), and reoperation (p = 0.01). No significant differences were found in Lysholm scores (p = 0.6), Tegner scores (p = 0.2), arthrometer measurements (p = 0.2), Pivot shift test results (p = 0.1), time to return to sport (p = 0.3), and failure rates (p = 0.7). Conclusions: LEAP for ACL reconstructions seems to be effective and safe. Most patients returned to their pre-injury level of sport after a mean of 6 months. LET-based ACL reconstruction may be associated with greater clinical outcomes and a higher reoperation rate compared to ALL-based reconstruction.

Combined Open-Anterolateral Ligament and Anterior Cruciate Ligament Reconstruction of the Knee: The "Open-ALL"

The addition of an extra-articular reinforcement, such as the anterolateral ligament (ALL) or a Lemaire's procedure, in anterior cruciate ligament reconstructions has shown good clinical results, with greater graft protection and a lower rerupture rate. Despite being a reproducible procedure, its application in cases of large, muscled knees or in obese patients can be challenging. This Technical Note describes the "Open-ALL" technique, using a mini-open approach for a combined anterior cruciate ligament and ALL reconstruction.

Knee ligament and meniscus injuries in children and teenagers

Knee ligament and meniscus injuries in children and teenagers are becoming more numerous because of increased sports participation but also better diagnosis. Meniscus injuries occur either in a normal meniscus or due to a congenital anomaly. The diagnosis is made clinically and confirmed by MRI. Treatment depends on the findings: meniscoplasty for discoid meniscus and primary repair of meniscus tears. Meniscus preservation is the rule. Injuries to the central pivot of the knee typically involve either the anterior cruciate ligament (ACL) or the tibial spine. Age, anatomy and the mechanism of injury determine the specific nature of the injury. The treatment of tibial spine fractures is highly standardized and typically surgical, with the aim of limiting residual laxity. ACL tears can be treated either by primary repair or non-surgically with guided rehabilitation. ACL reconstruction in skeletally immature patients is feasible as long as the growth plates are protected. The rate of residual laxity or retear is lower when anterolateral reconstruction is performed simultaneously. LEVEL OF EVIDENCE: Expert opinion.

Lateral Femoral Notch Sign Presence, Location, and Depth Are Not Associated With Primary Anterior Cruciate Ligament Reconstruction Failure: A Retrospective Case-Control Study

PURPOSE

To assess the relationship between the presence, depth, and location of the lateral femoral notch sign (LFNS) on preoperative magnetic resonance imaging (MRI) and the risk of anterior cruciate ligament reconstruction (ACLR) graft failure, as well as secondary return to sport (RTS) endpoints.

METHODS

Patients with primary ACLR failure between 2012 and 2021 were identified and matched to patients without primary ACLR failure by sex, age, and body mass index. Patients with incomplete medical records, inadequate follow-up, or concomitant lateral extra-articular tenodesis or anterolateral ligament reconstruction were excluded. The presence, depth, and location of the LFNS were recorded from patients' preoperative MRI. Intraoperative data, concomitant injuries, ACLR failure, and RTS were collected.

RESULTS

Of the 253 included patients, 158 (62.5%) were male, the mean age was 22 ± 9.1 years old, and the mean body mass index was 25.7 ± 5.7. 87(34.4%) had a LFNS on preoperative MRI. There was no difference in the prevalence of the LFNS between patients with primary ACLR failure (42 [32.1%]) and without primary ACLR failure (45 [36.9%]) (odds ratio 1.24, 95% confidence interval 0.74-2.08; P = .42). Among patients with the LFNS, there was no difference in mean depth between those with and without primary ACLR failure, or when stratifying depth by 1.0-1.5 mm, 1.5-2.0 mm, and >2.0 mm. The mean location of the LFNS from Blumensaat line did not differ between patients with or without primary ACLR failure, and RTS rate, level, and time were comparable between patients with and without the LFNS.

CONCLUSIONS

There was no significant difference in the presence, depth or location of the LFNS in patients with and without primary ACLR failure. Presence of the LFNS is not associated with additional risk of primary ACLR failure, and clinical outcomes were comparable in patients with and without the LFNS.

LEVEL OF EVIDENCE

Level IV, retrospective case-control study.

Influence of Extra-Articular Augmentation on Clinical Outcomes and Survival in Patients Undergoing Anterior Cruciate Ligament Reconstruction: A Pseudorandomized Study

Background and Objectives: Up to 27% of anterior cruciate ligament (ACL) reconstruction cases result in a residual positive pivot shift sign, indicating anteroposterior and rotational instability. This instability can compromise returning to sports and increase the risk of further injuries. The biomechanical role of the anterolateral ligament (ALL) in controlling internal knee rotation is well known. However, there are no clinical trials comparing isolated ACL repairs to those combined with ALL reconstruction. Our objective is to compare the results of these techniques, with a primary focus on assessing knee stability and graft survival, to provide evidence for optimizing surgical approaches, particularly for athletes and physically active individuals. Materials and Methods: An observational study using paired score matching as a method of pseudo-randomization was conducted. Subjects were divided into an ACL group and an ACL+ALL group. Demographic and clinical variables were collected, as well as those related to complications and survival. Results: A total of 236 patients were included, which was reduced to 74 ACL and 37 ACL+ALL after pseudo-randomization, resulting in preoperatively comparable groups. During follow-up, differences in favor of ALL reinforcement were found on the pivot shift test (p = 0.007). No differences were found with regard to the Lachman test (p = 0.201), the International Knee Documentation Committee (IKDC) knee score (p = 0.169), the IKDC subjective score (p = 0.095), intensity of pain (p = 0.928), or complications (p = 0.529). Nor were differences found in the limb symmetry index; the single hop test (p = 0.710); the triple hop test (p = 0.653); the crossover hop test (p = 0.682); the 6 meter timed hop test (p = 0.360); the normalized Y-balance test (YBT) (p = 0.459 anterior; p = 0.898 posterolateral; and p = 0.211 posteromedial directions); or the limb symmetry index of the composite YBT (p = 0.488). There were no differences either with respect to return to sports practice (p = 0.723) or survival (p = 0.798). Conclusions: Patients treated by means of the ACL+ALL technique obtained higher rotational stability, as measured by the pivot shift test, than those subjected to an isolated ACL repair. No differences were found with respect to Lachman test, complications, IKDC, pain, or survival.

Anterolateral corner of knee: Current concepts

The anatomy of the antero-lateral corner (ALC) has been the topic of recent interest, as evidenced by the increasing number of publications. Knowledge needs to be improved amongst clinicians regarding the anatomy and biomechanical function of this vital structure and its implications on the rotational stability of the knee. There has yet to be a consensus on the role of surgical procedures and their indications for addressing the instability associated with the injury to these structures. Through this article, the authors have tried to outline the existing literature regarding Anterolateral knee instability, the associated structures, and the management of its injuries, emphasising the role of the anterolateral capsule and reconstructive procedures in combined ligamentous knee injuries.

Clinical Outcomes of Isolated ACL Reconstruction Versus Combined ACL and ALL Reconstruction With Indication Guided by Intraoperative Ultrasound: A Propensity Score-Matched Study of 260 Patients With a Minimum 2-Year Follow-up

Background

Additional anterolateral ligament (ALL) reconstruction has been associated with improved clinical outcomes and reduced failure rates in anterior cruciate ligament (ACL) reconstruction. Despite the excellent clinical results reported, there is still a heated debate about its indications. Currently, the indications are mainly based on the patient's clinical criteria and not the imaging diagnosis of the injury of this ligament.

Purpose

To compare the clinical outcomes of patients undergoing isolated ACL reconstruction and combined ACL and ALL reconstruction conditioned to intraoperative ultrasound-guided diagnosis of the ALL lesion.

Study design

Cohort study; Level of evidence, 3.

Methods

A retrospective analysis of prospectively collected data was performed. Patients undergoing primary ACL reconstruction between January 2017 and January 2022 were included. Patients were excluded if they had a previous history of ipsilateral knee surgery or if they underwent other concomitant procedures, including multiligament reconstruction surgery or osteotomy. The decision to perform an ALL reconstruction in addition to isolated ACL reconstruction was based on ultrasound diagnosis of this lesion. At the end of the study period, further knee injury and any other reoperations or complications were recorded and compared between patients who had isolated ACL reconstruction (no-ALLR group) and combined ACL and ALL. Propensity score matching was performed between groups. A multivariable analysis using the penalized Cox model was performed to explore the relationship between the graft rupture, surgical procedure type, and potential explanatory variables.

Results

A total of 339 patients met the predefined eligibility criteria; 146 ACL reconstructions were performed in an isolated manner (no-ALLR group) and 193 were combined with ALL (ALLR group). After matching, 130 patients were allocated to each group. The mean follow-up was 36.7 months. The overall graft failure rate was 4.6% (6.9% in the no-ALLR group and 2.3% in the ALLR group; P = .076). The adjusted Cox regression showed that graft failure rate was nonsignificantly different between the groups (adjusted hazard ratio [HR], 0.36 [95% CI, 0.096-1.364]; P = .133). Younger age (≤20 years) was associated with graft failure (adjusted HR, 0.29 [95% CI, 0.121-0.719]; P = .007).

Conclusion

Combined ACL and ALL reconstruction conditioned to intraoperative ultrasound-guided diagnosis of the ALL lesion has an equivalent ACL graft failure rate to isolated ACL. Intraoperative ultrasound diagnosis of an ALL injury may be an indication for the addition of an ALL reconstruction.

Outcomes of combined single-bundle anterior cruciate ligament reconstruction and anterolateral structure reconstruction through a modified single femoral tunnel

PURPOSE

To explore the clinical outcomes of combining anterior cruciate ligament (ACL) reconstruction and anterolateral structure (ALS) reconstruction through a modified single femoral tunnel in patients with high risk of clinical failure.

METHODS

From December 2018 to August 2022, a total of 62 patients with ACL injury in our institution were enrolled in this study. All patients were associated with high risk of clinical failure, meeting the indications of ALS reconstruction. All patients accepted arthroscopic single-bundle ACL reconstruction and ALS reconstruction using hamstring autograft through a modified single femoral tunnel. Perioperative clinical outcome measurements consisted of functions, stability and safety evaluation at different time points (preoperative, postoperative three month, six month, one year, two year, three year and more). Functional evaluation included Lysholm score, Tegner activity scale, subjective and objective International Knee Documentation Committee (IKDC) score.

RESULTS

All patients, including 47 males and 15 females, aged 16-52 years with an average age of 29.3 ± 9.2 years, were followed up for 12-58 months. At the last follow-up, the Lysholm, subjective IKDC and Tegner activity scale (93.8 ± 7.0, 88.8 ± 10.7 and 5.8 ± 1.4 respectively) were significantly higher than those before surgery (65.0 ± 20.8, 51.2 ± 21.1 and 2.3 ± 1.3 respectively)(P < 0.05). Postoperative pivot shift and Lachman test were markedly improved (P < 0.05). One patient still had grade II pivot shift, defined as clinical failure. During follow-up, no graft rupture occurred according to magnetic resonance imaging and physical examination, no lateral compartment osteoarthritis were found in all patients.

CONCLUSIONS

Combined single bundle ACL reconstruction and ALS reconstruction through a modified single femoral tunnel could significantly improve knee function and stability with low related risk in patients with high risk of failure in ACL injury.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Shows Superior Graft Remodeling, Maturation, and Stability Compared With Isolated Anterior Cruciate Ligament Reconstruction

PURPOSE

To compare graft remodeling, as measured by magnetic resonance imaging (MRI), and clinical outcomes between patients who underwent isolated anterior cruciate ligament reconstruction (ACLR) versus combined anterior cruciate ligament and anterolateral ligament reconstruction (ACLR + ALLR).

METHODS

A retrospective review was conducted on patients who underwent primary ACLR with quadruple hamstring grafts between January 2019 and March 2022, with a minimum follow-up period of 2 years. Patients were categorized into two groups based on the addition of ALLR with tibialis anterior allografts: an isolated ACLR group and an ACLR + ALLR group. Graft ligamentization was assessed using signal-to-noise quotient (SNQ) values obtained from postoperative MRI scans, with lower SNQ values indicating superior graft remodeling. Clinical outcomes were evaluated through knee stability tests (pivot-shift test, side-to-side laxity), functional outcomes, and graft retear rates. The minimal clinically important difference (MCID) for the clinical scores was calculated using the distribution-based method of a half standard deviation of the delta (difference between postoperative and baseline values). Regression analyses identified potential predictive factors for inferior ACL graft remodeling.

RESULTS

A total of 122 patients in the isolated ACLR group and 54 in the ACLR + ALLR group were evaluated. The mean follow-up periods were similar between the groups (34.1 ± 7.4 months vs 36.4 ± 9.0 months; P = .755). The mean SNQ values were significantly lower in the ACLR + ALLR group compared to the isolated ACLR group (2.8 ± 1.6 vs 4.7 ± 3.5 mm, respectively; P = .001). Inferior ACL graft maturity was associated with an increased posterior tibial slope (P = .016), narrow notch width (P =.018), and concomitant medial meniscal lesion (P = .017). At the final evaluation, the ACLR + ALLR group demonstrated better rotational stability as indicated by the residual pivot-shift test (P = .005). No statistically significant differences were observed between the two groups in side-to-side laxity, functional outcomes, or graft retear rates. There were no differences in the percentage of patients achieving MCID for the International Knee Documentation Committee subjective score between the groups (P = .536).

CONCLUSIONS

Combined ACLR and ALLR resulted in superior graft remodeling, demonstrated by a mean SNQ value that was 1.9 lower than in isolated ACLR, along with improved rotational stability.

LEVEL OF EVIDENCE

Level III, retrospective, nonrandomized, comparative therapeutic study.

The presence of a Segond fracture in ACL-injured patients is associated with increased internal tibial rotation on preoperative MRIs

BACKGROUND

Segond fracture is considered a component of the anterolateral complex (ALC) injury, yet the underlying cause and clinical outcomes of this bony avulsion remain subjects of debate. Additionally, MRI measurements of altered tibiofemoral position in anterior cruciate ligament (ACL)-injured patients with a Segond fracture have not been reported. The purpose of this study is to measure the rotational tibiofemoral position on MRI in ACL-injured patients with a Segond fracture.

METHODS

A total of 44 patients with a primary ACL injury and a concomitant Segond fracture were included in the Segond fracture group, with the time from injury to MRI within 3 months. Avulsion was confirmed via preoperative computed tomography (CT) scans. The control group comprised 44 matched patients with primary ACL injury and an MRI-determined ALC injury but without a Segond fracture, also with the time from injury to MRI within 3 months. The MRI-determined ALC injury included injuries to the anterolateral ligament, Kaplan fibers, and anterolateral joint capsule, as identified based on previous studies. Sex, age, and BMI were matched between the two groups using propensity score matching (PSM). Arthroscopic findings, concomitant collateral ligament injuries, and preoperative MRI measurements were compared between the two groups.

RESULTS

The Segond fracture group demonstrated a higher frequency of concomitant patellar and femoral trochlear injuries (p = 0.0110) and lateral collateral ligament injuries (p = 0.0121) compared to the control group. Additionally, significantly increased internal rotational tibial subluxation (IRTS) (p = 0.0095) and axial internal tibial rotation (ITRa) (p = 0.0306) were observed in the Segond fracture group. A strong positive correlation was found between IRTS and ITRa (rp = 0.8201), indicating that these two tibial rotation measurement methods were correlated. No significant differences were observed in the measurements of anteroposterior tibiofemoral position and posterior tibial slope (PTS) between the two groups.

CONCLUSION

The presence of a Segond fracture was associated with significantly increased internal tibial rotation measured on MRIs, suggesting that this bony avulsion may represent a more severe form of ALC injury in ACL-injured patients and should be managed with caution.

Characterization of bone marrow edema patterns among patients with Segond fracture in the setting of acute anterior cruciate ligament injury: A comparative MRI study

PURPOSE

The purpose of this study is to investigate the anatomic distribution of bone marrow edema on MRI among patients who sustained a Segond fracture compared to those with an isolated ACL tear.

METHODS

A retrospective cohort study was performed of patients aged 18-40 years old who presented with an acute isolated ACL tear between January 2012 and May 2022. Two blinded readers reviewed all knee MRIs to assess bone marrow edema using the Whole-Organ Magnetic Resonance Imaging Score and the area of each sub-compartment was scored.

RESULTS

There were 522 patients in the final analysis, of which 28 patients (5.4%) were identified to have a Segond fracture. The Segond group demonstrated significantly greater rates of WORMS grades 2 and 3 in the central lateral femoral condyle, as well as the anterior, central, and posterior lateral tibial plateau. Furthermore, the Segond group demonstrated significantly greater rates of WORMS grades 2 and 3 in the central medial femoral condyle and the anterior medial tibial plateau. Bone edema at the central lateral femoral condyle (R = 0.034, p = 0.019) and central tibial plateau (R = 0.093, p = 0.033) were significantly correlated with lateral meniscus tears, while the edema in the posterior medial femoral condyle was correlated with medial meniscus tears (R = 0.127, p = 0.004).

CONCLUSION

Patients who present with ACL tear and a concomitant Segond fracture demonstrate significantly more extensive bone marrow edema in both the medial and lateral compartments of the knee compared to patients with an isolated ACL tear.

Associated Medial Meniscal Injury with ACL Reconstruction Results in Poorer Strength and Jump Tests Outcomes: A 6-Month Analysis of 504 Patients from the MERIScience Cohort

Background/Objectives: After anterior cruciate ligament reconstruction (ACLR), a 6-month composite test is recommended during rehabilitation before the return to sport, and the influence of a meniscal tear is not known. The hypothesis was that the location and treatment of meniscus injuries could influence the results of the composite test. Methods: A retrospective single-center study was carried out of prospectively collected data involving 504 patients who performed a composite test 6 months after ACLR. Isolated ACLR was compared to ACLR with medial meniscus injuries (MM), lateral meniscus injuries (LM), and bimeniscal injuries (BM) using a composite test including a single-leg squat (SLS), a single-leg landing (SLL), a single hop for distance (SHD), a triple hop for distance (THD) and a side-hop test (Side-HT), isokinetic strength tests, and an assessment of the anterior cruciate ligament-return to sport after injury (ACL-RSI). Results: Compared with isolated ACLR, MM injury was associated with a quadricipital deficit at a velocity of 240°/s (14% ± 14% vs. 18% ± 18%, p = 0.02), hamstring deficit at 30°/s (14% ± 18% vs. 18% ± 18%, p = 0.02) and an increase in the hamstring/quadricipital ratio at 240°/s (68% ± 27% vs. 80% ± 67% p = 0.02). Furthermore, ACLR + MM or ML injuries in the operated knee generated an increase in the dynamic valgus frequency detected by the SLS, respectively (40% ± 49% vs. 51% ± 50%, p = 0. 05) and (40% ± 49% vs. 54% ± 50%, p = 0.02). Meniscal repair and meniscectomies showed no differences. Conclusions: These results show that meniscal injuries lead to muscle imbalance for MM injuries and impaired neuromuscular control for MM and LM injuries and suggest that meniscal repairs should be done. Moreover, rehabilitation must be adapted to meniscus injuries.

Do we need a guideline for all: a qualitative study on the experiences of male athletes following anterior cruciate ligament reconstruction

BACKGROUND

Considering the low rate of qualitative studies on athletes with anterior cruciate ligament reconstruction (ACLR), aiming to access in-depth data, we thought that the utilization of the qualitative method would allow us to collect the appropriate and sufficient data to yield novel findings and achieve sound conclusions. The study's aim was to investigate anterior cruciate ligament (ACL) injury experience processes in athletes who had undergone isolated ACLR, reveal the clinically related milestones, and highlight the necessary gaps.

METHODS

Semi-structured interview techniques, in-depth follow-up questions, and thematic analysis were used to explore the experiences of participants with isolated ACL injuries 1-3 years after surgical treatment. The study was conducted in the Orthopaedics and Traumatology outpatient clinic of the Adana City Training and Research Hospital and included 14 male athletes who had undergone isolated primary ACLR. The study group's demographic and qualitative data were collected in the first week of September 2023. The member checking process was completed in the third following week. A thematic analysis checklist was used to ensure the reliability of the thematic analysis. The Consolidated Criteria for Reporting of Qualitative Research (COREQ) guidelines were followed.

RESULTS

The experiences of 14 patients (22.78 ± 3.76 years, all males) were summarized into four themes that emerged from the data analysis process: 'The Distinctions in the Participants' Experiences Regarding the Moment of Injury,' 'Gathering Information about the ACL Injury,' 'Factors That Facilitate The Treatment Process and Reinforce Positive Experiences,' and 'Desperate Plight: Main Points of Patients' Negative Experiences.' Based on the main themes, there were 14 subthemes.

CONCLUSIONS

Our study revealed that varying perceptions of ACL injury presented by the participants, which were caused by all stakeholders, including themselves, the professional environment, family members, social network, and the healthcare staff, showed that the physical and psychological impacts of the injury were observed in different severity levels at each stage of the process. We believe that an extensive guide for athletes with ACL injuries that includes all components of well-being and displays the required details for the sports club/coach, family/companion, and physician.

The role of anterolateral complex surgery and slope-reducing osteotomies in revision ACL reconstructions: a narrative review

Background and Objective

Anterior cruciate ligament reconstruction (ACLR) failures occur for various reasons including residual laxity, untreated concomitant injuries, poor graft quality, and high tibial slope. Various additional procedures can help to decrease revision ACLR failures including anterolateral complex (ALC) procedures and slope-reducing osteotomies for patients with high tibial slopes. This narrative review aims to review the literature on the roles of ALC augmentation procedures and slope-reducing osteotomies in the setting of patients undergoing revision ACLRs.

Methods

A narrative review of relevant literature was performed in July 2024. Studies about anterolateral complex reconstructions and slope-reducing osteotomies in revision ACLRs were included.

Key Content and Findings

The literature reported that lateral extra-articular tenodesis (LET) and anterolateral ligament reconstructions (ALLR) can be used in revision ACLR cases to significantly reduce clinical knee laxity and the risk of repeated graft failure. There is not currently a strong opinion on which ALC procedure is superior. There are reported slight differences in lateral knee pain and knee stiffness, but both similarly significantly improve clinical and functional outcomes. In revision ACLR cases that also have a high posterior tibial slope (PTS), a slope-reducing tibial osteotomy is warranted. An anterior closing wedge proximal tibial osteotomy (ACW-PTO) significantly reduces anterior tibial translation and graft failure. There is concern about the changes to patellar height, but the literature has found that such changes are either slight or absent by 6 months postoperatively.

Conclusions

The risk of ACLR failure is increased by risk factors like high tibial slope, preoperative knee laxity, and prior ACLR rupture. Anterolateral complex procedures and slope-reducing osteotomies may be used to address these specific concerns and reduce the risk of graft rupture. For revision ACLR cases with lower PTS, augmentation with a LET or an ALLR to reduce the risk of graft failure and improve rotational stability may be warranted. In the setting of a revision ACLR in patients with a high PTS of ≥12°, a concomitant ACW-PTO and ALC procedure should be considered to decrease the risk of an ACLR graft failure.

CT of Periarticular Adult Knee Fractures: Classification and Management Implications

Periarticular knee fractures, which include fractures of the distal femur, tibial plateau, and patella, account for 5%-10% of musculoskeletal injuries encountered in trauma centers and emergency rooms. These injuries are frequently complex, with articular surface involvement. Surgical principles center on reconstruction of the articular surface as well as restoration of limb length, alignment, and rotation to reestablish functional knee biomechanics. Fixation principles are guided by fracture morphology, and thus, CT with multiplanar reformats and volume rendering is routinely used to help plan surgical intervention. Fractures involving the distal femur, tibial plateau, and patella have distinct management considerations. This comprehensive CT primer of periarticular knee fractures promotes succinct and clinically relevant reporting as well as optimized communication with orthopedic trauma surgeon colleagues by tying fracture type and key CT findings with surgical decision making. Fracture patterns are presented within commonly employed fracture classification systems, rooted in specific biomechanical principles. Fracture typing of distal femur fractures and patellar fractures is performed using Arbeitsgemeinschaft für Osteosynthesefragen/Orthopedic Trauma Association (AO/OTA) classification schemes. Tibial plateau fractures are graded using the Schatzker system, informed by a newer explicitly CT-based three-column concept. For each anatomic region, the fracture pattern helps determine the surgical access required, whether bone grafting is warranted, and the choice of hardware that achieves suitable functional outcomes while minimizing the risk of articular collapse and accelerated osteoarthritis. Emphasis is also placed on recognizing bony avulsive patterns that suggest ligament injury to help guide stress testing in the early acute period. ©RSNA, 2024 Supplemental material is available for this article.

It is challenging to reproduce both anatomical and functional aspects of anterolateral reconstruction: postoperative 3D-CT analysis of the femoral tunnel position

BACKGROUND

This study aimed to evaluate the femoral tunnel position and fiber length of the anterolateral ligament (ALL) reconstruction compared with the natural anatomy of the ALL. We also evaluated whether the femoral tunnel position would affect residual pivot shift.

METHODS

This study was a retrospective review of 55 knees that underwent ALL reconstruction considering the anatomical and functional aspects, during primary anterior cruciate ligament (ACL) reconstruction in the presence of a high-grade pivot shift or revisional ACL reconstruction. We determined the position of the femoral tunnel and the length of graft using a three-dimensional (3D)-computed tomography (CT) model after ALL reconstruction. We also measured graft excursion during surgery and examined pivot shift 2 years after surgery. We conducted a subgroup analysis of femoral tunnel position, fiber length, isometricity, and residual pivot shift depending on whether the tunnel was anterior or posterior to the lateral epicondyle (LE). We also performed a subgroup analysis depending on whether the ACL reconstruction was primary or revisional.

RESULTS

The mean femoral tunnel position was 2.04 mm posterior and 14.5 mm proximal from the center of the LE. The mean lengths of the anterior and posterior fibers were 66.6 and 63.4 mm, respectively. The femoral tunnel was positioned more proximally than the anatomical position, and both anterior and posterior ALL fibers were longer than the natural anatomy. The anteroposterior femoral tunnel position was significantly correlated with anterior (p = 0.045) and posterior (p = 0.037) fiber excursion. In the subgroup analysis, there was no significant difference in the residual pivot shift between the posterior and anterior tunnel positions. However, there were significant differences for proximal position (p < 0.001) and fiber length (p = 0.006). There was no significant difference between primary and revisional ACL regarding femoral tunnel position and fiber lengths.

CONCLUSION

It is challenging to reproduce both anatomical and functional aspects of ALL reconstruction in both primary and revision ACL reconstruction. Especially for functional reconstruction, the femoral tunnel tended to be positioned more proximally than the anatomical position. However, the femoral tunnel position did not affect functional clinical outcomes at the 2-year follow-up.

LEVEL OF EVIDENCE

Level IV Case series.

ACL reconstruction combined with anterolateral structures reconstruction for treating ACL rupture and knee injuries: a finite element analysis

Introduction: The biomechanical indication for combining anterolateral structures reconstruction (ASLR) with ACL reconstruction (ACLR) to reduce pivot shift in the knee remains unclear. This study aims to investigate knee functionality after ACL rupture with different combinations of injuries, and to compare the effectiveness of ALSR with ACLR for treating these injuries. Methods: A validated finite element model of a human cadaveric knee was used to simulate pivot shift tests on the joint in different states, including 1) an intact knee; 2) after isolated ACL rupture; 3) after ACL rupture combined with different knee injuries or defect, including a posterior tibial slope (PTS) of 20°, an injury to the anterolateral structures (ALS) and an injury to the posterior meniscotibial ligament of the lateral meniscus (LP); 4) after treating the different injuries using isolated ACLR; v. after treating the different injuries using ACLR with ALSR. The knee kinematics, maximum von Mises stress (Max.S) on the tibial articular cartilage (TC) and force in the ACL graft were compared among the different simulation groups. Results and discussion: Comparing with isolated ACL rupture, combined injury to the ALS caused the largest knee laxity, when a combined PTS of 20° induced the largest Max.S on the TC. The joint stability and Max.S on the TC in the knee with an isolated ACL rupture or a combined rupture of ACL and LP were restored to the intact level after being treated with isolated ACLR. The knee biomechanics after a combined rupture of ACL and ALS were restored to the intact level only when being treated with a combination of ACLR and ALSR using a large graft diameter (6 mm) for ALSR. However, for the knee after ACL rupture combined with a PTS of 20°, the ATT and Max.S on the TC were still greater than the intact knee even after being treated with a combination of ACLR and ALSR. The finite element analysis showed that ACLR should include ALSR when treating ACL ruptures accompanied by ALS rupture. However, pivot shift in knees with a PTS of 20° was not eliminated even after a combined ACLR and ALSR.

The presence of a deep lateral femoral notch sign in ACL-injured patients is associated with a 2.7° steeper posterior tibial slope and a 19% higher frequency of lateral meniscal injuries

PURPOSE

The purpose of this study was to study the relationship between the presence of a deep lateral femoral notch sign (DLFNS) in anterior cruciate ligament (ACL)-injured patients and a higher posterior lateral tibial slope (LPTS), a reduced meniscal bone angle (MBA), a higher LPTS/MBA ratio and a higher incidence of concomitant injuries in primary ACL tears.

METHODS

A retrospective case-control study was performed in patients submitted to primary ACL reconstruction with an available preoperative magnetic resonance imaging (MRI) scan. Patients with ACL tears and a femoral impactation with a depth ≥2 mm were assorted to the DLFNS group and patients with ACL tear and without a DLFNS to the control group. LPTS and MBA were measured in MRI. The presence of concomitant injuries (meniscal, posterior cruciate ligament, medial collateral ligament, lateral collateral ligament and bone injuries) was assessed in MRI. Quantitative data are presented in the median ± interquartile range (IQR).

RESULTS

There were 206 patients included in the study, with 46 patients assorted to the DLFNS group and 160 patients to the control group. In the DLFNS group, the median LPTS was 6.7° (IQR: 4.0-8.2) versus 4.0° in the control group (IQR: 2.2-6.5) (p = 0.003). The LPTS/MBA ratio was significantly higher in the DLFNS group, with a median of 0.32 (IQR: 0.19-0.44), in comparison to the control group, with a median of 0.19 (IQR: 0.11-0.31) (p < 0.001). The multivariable logistic regression analysis showed that the LPTS is an independent risk factor to having a DLFNS (odds ratio [OR] = 1.161; 95% confidence interval [CI]: 1.042-1.293, p = 0.007). There was a higher incidence of concomitant lateral meniscal injuries in the DLFNS group (67% vs. 48%, p = 0.017).

CONCLUSIONS

In patients with ACL tears, the presence of a DLFNS is associated with a steeper lateral posterior tibial slope, as well as a higher incidence of concomitant lateral meniscal injuries.

LEVEL OF EVIDENCE

Level III.

Effect of Preoperative Anterolateral Ligament Injury on Outcomes After Isolated Acute ACL Reconstruction With Hamstring Graft: A Prospective Study With Minimum 5-Year Follow-up

BACKGROUND

The potential influence of a preoperative anterolateral ligament (ALL) lesion seen on magnetic resonance imaging (MRI) on the mid- and long-term surgical outcomes of anterior cruciate ligament (ACL) reconstruction is still controversial.

PURPOSE

To evaluate the clinical outcomes and failure rate of isolated ACL reconstruction at a minimum 5-year follow-up in patients with and without ALL injury diagnosed preoperatively using MRI.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A prospective cohort of patients with acute ACL injury was divided into 2 groups based on the presence (ALL injury group) or absence (control group) of ALL injury on preoperative MRI. This is a longer-term follow-up study of a previously published study that had a minimum 2-year follow-up. Both groups underwent anatomic isolated reconstruction of the ACL. The Lysholm and subjective International Knee Documentation Committee scores, KT-1000 arthrometer and pivot-shift tests, reconstruction failure rate, incidence of contralateral ACL injury, presence of associated meniscal injury, and presence of knee hyperextension were evaluated. The evaluation at the 5-year follow-up was also compared with the same patient's evaluation at 2 years of follow-up.

RESULTS

A total of 156 patients were evaluated. No significant differences were found between the groups in the preoperative evaluation. In the postoperative evaluation, patients in the ALL injury group had a higher reconstruction failure rate (14.3% vs 4.6% for the control group; P = .049) and worse clinical outcomes according to the Lysholm scores (85.0 ± 10.3 vs 92.3 ± 6.6; P < .00001). Although the pivot-shift test results were similar, anteroposterior translation using the KT-1000 arthrometer revealed worse results for the ALL injury group (2.8 ± 1.4 mm vs 1.9 ± 1.3 mm; P = .00018). Patients in the ALL injury group also had an increase in KT-1000 arthrometer values from 2 to 5 years (2.4 ± 1.6 vs 2.8 ± 1.4; P = .038). Patients in the control group had no differences in outcomes from 2 to 5 years of follow-up.

CONCLUSION

Combined ACL and ALL injuries were associated with significantly less favorable outcomes than were isolated ACL injuries at a minimum follow-up of 5 years after isolated ACL reconstruction with hamstring autograft. Patients with concomitant ALL injury showed a higher failure rate and worse functional scores. Also, knee stability tended to slightly worsen from 2 to 5 years in cases of associated ALL injury.

Combined Anterolateral Ligament Reconstruction Results in Better Knee Stability and More Satisfactory Subjective Outcomes in Non-Athlete Patients Undergoing Revision Anterior Cruciate Ligament Reconstruction

Background: Consensus has not yet been reached regarding combined anterior cruciate ligament reconstruction (ALLR) with revisional anterior cruciate ligament reconstruction (RACLR). We aimed to compare the clinical outcomes between patients who underwent isolated RACLR and those who underwent RACLR combined with ALLR. Methods: Between June 2010 and June 2021, 49 patients who underwent RACLR were retrospectively reviewed over a 24-month follow-up. Patients were categorized into the isolated RACLR (n = 37, group 1) or combined ALLR group (n = 12, group 2). Clinical outcomes were evaluated with several patient-reported outcome measures (PROMs) and minimal clinically important differences (MCIDs) for each PROM. The side-to-side difference (SSD) of the anterior instability was measured. The pivot-shift test was performed. Results: Baseline characteristics showed no differences between the groups. PROMs showed no significant differences between the groups at the 2-year follow-up. Group 2 was superior to group 1 in the MCID achievement rate for Lysholm knee and International Knee Documentation Committee (IKDC) subjective scores at 24 months postoperatively. At the final follow-up, the proportion of IKDC grade A in SSD for anterior laxity was higher in group 2 than in group 1 (58.3% versus [vs.] 18.3%, p = 0.009), and the proportion of pivot-shift grade 0 was also higher in group 2 (66.7% vs. 27.0%, p = 0.013). The "near return to activity" rate was also higher in group 2 than in group 1 (83.3% vs. 45.9%, p = 0.043). Conclusions: Combining ALLR with RACLR in non-athletes results in a higher proportion of patients with less mechanical graft failure and satisfactory clinical outcomes.

Magnetic Resonance Imaging Features of Anterolateral Ligament in Young Adults without Anterior Cruciate Ligament Injury: Preliminary Evaluation

This study aimed to characterize the Magnetic Resonance Imaging (MRI) features of the Anterolateral Ligament (ALL) in young adults without Anterior Cruciate Ligament (ACL) injury and evaluate its visibility using MRI. In this retrospective analysis, MRI scans of 66 young adults without ACL injuries were assessed by two radiologists. The ALL was examined from its bone-to-bone attachment between the lateral femoral epicondyle and the lateral tibia. The visibility of the ALL was classified as normal, probably normal, abnormal, or non-visualized, based on ligament continuity and thickness relative to the Meniscotibial Ligament (MTL). A continuous structure with thickness equal to or greater than the MTL was considered normal; continuous but wavy and thin features were categorized as probably normal; discontinuity and angulation were deemed abnormal. The proximal attachment of the ALL was categorized as anterior, central, or posterior to the Fibular Collateral Ligament (FCL), while the distal attachment was noted as either at the same location or distal to the MTL. The ALL was identified in 87.9-95.5% of knees and was non-visualized in 4.5-12.1% of cases. Continuous ligamentous structures were observed in 63.7-71.2% of knees (normal in 30.3-37.9%; probably normal in 27.3-40.9%), whereas 19.7-30.3% exhibited abnormal features. Inter-observer agreement was moderate to substantial (κ = 0.66, 0.56), and intra-observer agreement was substantial to excellent (κ = 0.82, 0.66). Among the 58 visible ALLs, proximal attachments were predominantly anterior (63.8%) or central (32.8%) to the FCL, with a minority posterior (1.7%). In total, 4 of the 19 central insertions were incorporated into the FCL mid-substance, and one case was blended into the meniscofemoral ligament. Distal attachments were equally distributed between the same location (50%) and distal to the MTL (50%) (mean 3.7 mm distal). In conclusion, MRI was feasible for detecting the ALL in most young adults without ACL injury, revealing continuous ligament structures in about two-thirds of cases. Approximately 40% of cases exhibited a thickness equal to or greater than the MTL, with the majority of proximal attachments located anterior to the FCL and distal attachments evenly divided between the same insertion and distal to the MTL.

Dynamic radiostereometry can objectively quantify the kinematic laxity patterns and rotation instability of the knee during a pivot-shift test

PURPOSE

The pivot-shift test is used to clinically assess knee instability in patients with anterior cruciate ligament (ACL) lesions; however, it has low interobserver reliability. Dynamic radiostereometry (dRSA) is a highly precise and noninvasive method for the objective evaluation of joint kinematics. The purpose of this study was to quantify precise knee kinematics during a pivot-shift test using dRSA imaging.

METHOD

Eight human donor legs, including hemipelvises, were evaluated. Arthroscopic intervention was performed inducing ligament lesions in the ACL, and anterolateral ligament (ALL) section was performed as a capsular incision. The pivot-shift test was recorded with dRSA on knees with intact ligaments, ACL-deficient and ACL + ALL-deficient knees.

RESULTS

A pivot-shift pattern was identifiable after ligament lesion, as a change in tibial posterior drawer velocity from 7.8 mm/s (95% CI: 3.7; 11.9) in ligament intact knees to 30.4 mm/s (95% CI 23.0; 38.8) after ACL lesion to 35.1 mm/s (95% CI 23.4; 46.7) after combined ACL-ALL lesion. The anterior-posterior drawer excursion increased from 2.8 mm (95% CI 2.1; 3.4) in ligament intact knees to 7.2 mm (95% CI 5.5; 8.9) after ACL lesion to 7.6 mm (95% CI 5.5; 9.8) after combined lesion. A statistically significant increase in tibial external rotation towards the end of the pivot-shift motion was observed when progressing from intact to ACL + ALL-deficient knees (p < 0.023).

CONCLUSION

This experimental study demonstrates the feasibility of dRSA to objectively quantify the kinematic laxity patterns of the knee during the pivot-shift test. The dynamic parameters obtained through dRSA revealed the kinematic changes from ACL to combined ACL-ALL ligament lesion.

LEVEL OF EVIDENCE

Not applicable.

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.

Outcomes of Anterior Cruciate Ligament Reconstruction in Patients with Associated Anterolateral Ligament Injury

Objective  To evaluate if there is a significant difference in the outcomes of isolated anterior cruciate ligament (ACL) reconstruction in patients with or without associated anterolateral ligament (ALL) injury. Methods  We conducted a retrospective cross-sectional study through the analysis of medical records and the application of the questionnaires of the Lysholm Knee Scoring Scale and the International Knee Documentation Committee (IKDC) Subjective Knee Form to patients undergoing isolated ACL reconstruction. Results  The 52 participants included were divided into two groups: 19 with associated ALL injury and 33 with no associated ALL injury. None of the patients with associated ALL injury suffered an ACL rerupture, and 21.1% presented injuries to other knee structures after surgery. Among the patients with no associated injury, 6.1% suffered ACL rerupture, and 18.2% presented injuries to other structures after surgery ( p  = 0.544). Return to activities at the same level as that of the preoperative period occurred in 60% of the patients with associated ALL injury and in 72% of those with no associated injury ( p  = 0.309). The mean score on the Lysholm Knee Scoring Scale was of 81.6 points in patients with associated ALL injury, and of 90.1 in those with no associated injury ( p  = 0.032). The mean score on the IKDC Subjective Knee Form was of 70.3 points in patients with associated ALL injury and of 76.7 in those with no associated injury ( p  = 0.112). Conclusion  There was no statistically significant difference regarding graft injuries or new injuries to other structures, satisfaction with the operated knee, or the score on the IKDC Subjective Knee Form. Return to activity was similar in the groups with and without associated ALL injuries. The scores on the Lysholm Knee Scoring Scale were better, with a statistically significant difference in the group with no associated ALL injuries.

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.

New Anatomic Anterolateral Ligament Reconstruction Used in a Complex Revision ACL Reconstruction

Background

Anterior cruciate ligament reconstructions (ACLRs) are performed to restore knee biomechanics, increase knee stability, and slow the progression of osteoarthritis. After ACLRs, many patients still have residual anterolateral instability which is a risk factor for ACL graft failure. An anterolateral ligament reconstruction (ALLR) attempts to restore the native function of the anterolateral complex to augment the ACL. Performing an ALLR with an ACLR has been reported to reduce symptoms of instability and improve clinical outcomes.

Indications

While no definitive indication for an ALLR has been set, current considerations include high posterior tibial slope >12°, revision ACLR, high-grade pivot shift, skeletally immature patients, hyperlaxity, and patients in high-level sports.

Technique Description

The preoperative assessment includes a thorough physical examination with special attention paid to rotational laxity assessed via the pivot-shift examination. Imaging should include standard radiographic series (anteroposterior, posteroanterior flexion, lateral, and sunrise views), long-leg mechanical axis views to assess coronal plane alignment and standing lateral ACL stress radiographs to assess sagittal alignment and objective instability. The iliotibial band ALLR graft is harvested first. An 8-cm long by 1-cm wide strip of the inferior iliotibial band is harvested in a standard fashion, leaving the distal aspect attached to Gerdy's tubercle. An anchor is placed centered upon the native ALL distal tibial insertion. The native ALL femoral origin is identified at 4.7 mm posterior and proximal to the fibular collateral ligament, and a second suture anchor is placed at this point. Final fixation is performed after the final fixation of the ACLR graft.

Results

A study by Pioger et al reported that patients with ACLR and ALLR had significantly less reoperation rate than patients with isolated ACLR, 8.9% versus 20.5% respectively. Lee et al found that a revision ACLR in combination with an ALLR was effective in reducing rotational laxity, which was assessed by the pivot-shift test.

Discussion

We describe a technique for a new anatomic ALLR using the iliotibial band that attempts to restore the native ALL anatomy. This surgical technique effectively restores rotational laxity and improves knee stability.

Patient Consent Disclosure Statement

The author(s) attests that consent has been obtained from any patient(s) appearing in this publication. If the individual may be identifiable, the author(s) has included a statement of release or other written form of approval from the patient(s) with this submission for publication.

Segond fracture: an indicator for increased risk of lateral meniscus injury in patients with acute anterior cruciate ligament ruptures

PURPOSE

The purpose of this study was to investigate the incidence and anatomic distribution of meniscus injury in patients who have sustained acute ACL injuries with and without concomitant Segond fracture. We hypothesized that patients who have sustained a torn ACL with a concomitant Segond fracture would have a higher incidence of lateral meniscal injuries than patients with an isolated ACL injury.

METHODS

Patients who underwent ACL reconstruction from 2012 to 2022 were retrospectively reviewed. Segond fractures were identified on knee radiographs. Inclusion criteria were age 18-40, injury during sports activity, and reconstruction within 90 days of injury. Sports activity, anatomic location of meniscus injury, and meniscus treatment were documented. Multivariable regression was used to identify predictors of meniscus injury/treatment.

RESULTS

There were 25 of 603 (4.1%) patients who had an ACL tear with concomitant Segond fracture. The incidence of lateral meniscus injury in the Segond group (72%) was significantly higher than in the non-Segond cohort (49%; p = 0.024). A significantly smaller proportion of medial meniscus injuries among patients with Segond fractures were repaired (23.1%) compared to the non-Segond group (54.2%; p = 0.043). Multivariate analysis found patients with Segond fractures to have increased odds of lateral meniscus injury (OR 2.68; [1.09, 6.60], p = 0.032) and were less likely to have medial meniscus injuries repaired (OR 0.35; [0.15, 0.81], p = 0.014). Additionally, males had increased odds of lateral meniscus injury (OR 1.54; [1.08 - 2.91], p = 0.017), which were more likely to require repair (OR 1.48; [1.02, 2.14], p = 0.038).

CONCLUSIONS

Among acute ACL injuries, the incidence of lateral meniscus injury is greater among patients with Segond fractures. Patients with Segond fracture were less likely to undergo repair of medial meniscal injuries.

Anatomic Anterolateral Ligament Reconstruction with Iliotibial Band Graft and Concomitant Anterior Cruciate Ligament Reconstruction

Anterior cruciate ligament (ACL) reconstruction (ACLR) attempts to restore native ACL function. Persistent anterolateral instability is a common symptom after ACLR that can lead to worse patient outcomes. Additional surgeries, like anterolateral ligament reconstruction (ALLR), can augment the ACL graft and help increase anterolateral rotational stability. Certain indications for ACLR with ALLR include high-grade pivot shift, increased posterior tibial slope (>12°), revision ACLR, and concomitant ligamentous or meniscal injuries. We describe an anatomic ALLR technique using an 8 cm long × 1 cm wide strip of the inferior aspect of the iliotibial band fixed at the native attachment sites of the ALL.

Patients With Segond Fracture Demonstrate Similar Rates of Return to Sport and Psychological Readiness After Anterior Cruciate Ligament Reconstruction: A Matched Cohort Study at Minimum 2-Year Follow-Up

PURPOSE

To compare clinical outcomes, rate of return to sports, and psychological readiness among patients undergoing anterior cruciate ligament reconstruction (ACLR) with and without concomitant Segond fracture.

METHODS

We retrospectively identified patients who underwent primary ACLR from January 2012 to December 2020 with minimum 2-year follow-up. Exclusion criteria were additional ligamentous injury, age <16 years, or a concomitant lateral augmentation procedure. Preoperative knee radiographs were reviewed to identify Segond fractures. Identified patients were matched 1:2 to controls by age/sex/body mass index/graft type. Charts were reviewed for pre- and postoperative knee stability. Surveys administered included preinjury sport participation and return status, Lysholm score, Tegner activity scale, and ACL-Return to Sport Index (ACL-RSI), a metric of psychological sport readiness. Multivariable logistic regression was conducted to identify predictors of return to sport.

RESULTS

There were 120 patients who were included in the final analysis (40 Segond, 80 controls) at a mean follow-up of 5.7 ± 2.4 years. A total of 52.5% of patients received bone-patellar tendon-bone autograft. The overall rate of return to sport was 79.5% in the Segond group compared with an 83.8% rate of return in the control group (P = .569). In total, 48.7% of the Segond group and 56.8% of the control group returned to their preinjury level of sport (P = .415). Lysholm (89.6 ± 10.3 vs 85.4 ± 16.7, P = .296), Tegner (5.7 ± 1.8 vs 6.1 ± 2.2, P = .723), and ACL-RSI (62.2 ± 25.4 vs 56.6 ± 25.4, P = .578) scores were similar between Segond and control groups. There was a single graft failure in the Segond group 5 years' postoperatively. Increasing ACL-RSI score was significantly predictive of return to sport (P < .001).

CONCLUSIONS

Patients who had an ACL tear and a concomitant Segond fracture who underwent isolated ACLR without lateral augmentation procedures had similar clinical outcomes and rates of return sport compared with a matched isolated ACLR control group at minimum 2-year follow-up. There was no significant difference in psychological readiness between groups as measured by the ACL-RSI.

LEVEL OF EVIDENCE

Level III, retrospective cohort study.

A lateral extra-articular tenodesis without additional hardware: Surgical technique and biomechanical comparison with an anatomic anterolateral ligament reconstruction in the augmentation of anterior cruciate ligament reconstruction

BACKGROUND

The aims of this study were to describe a lateral extra-articular tenodesis (LET) using no additional hardware and compare the tibiofemoral kinematics of anterior cruciate ligament (ACL) reconstruction augmented with either the LET or a standard anatomic anterolateral ligament (ALL) reconstruction using intra-tunnel fixation.

METHODS

Ten cadaveric knees were mounted on a robotic testing system and underwent a kinematic assessment of anterior tibial translation and internal tibial rotation under a simulated pivot-shift in the following states: ACL-intact, ACL-sectioned, ACL-sectioned/anterolateral complex (ALC)-sectioned, ACL-reconstructed/ALC-sectioned, ACL-reconstructed/ALL-reconstructed, and ACL-reconstructed/LET. For the LET, an iliotibial autograft was passed under the fibular collateral ligament and secured to the femur with the pull sutures of the ACL reconstruction femoral cortical suspensory fixation device, positioned at the distal ridge of Kaplan's fibers.

RESULTS

Anterior tibial translation was restored to normal by ACL reconstruction without meaningful benefit of augmentation with LET or ALL. ACL reconstruction restored internal tibial rotation close to normal between 0° and 30°, but increased internal tibial rotation persisted between 45° and 90°. Augmentation of ACL reconstruction with the LET reduced internal rotation close to normal between 45° and 90°, whereas increased internal rotation persisted after ALL reconstruction.

CONCLUSION

ACL reconstruction and LET are complementary in controlling tibiofemoral kinematics of knees with a combined ACL and ALC injury: ACL reconstruction restored native tibiofemoral kinematics except for internal rotation at flexion greater than 30°. The increased internal rotation at flexion greater than 30° was restored to normal with an LET, but not with an ALL reconstruction.

Patients With More Than 6.5° of Knee Hyperextension are 14.6 Times More Likely to Have Anterior Cruciate Ligament Hamstring Graft Rupture and Worse Knee Stability and Functional Outcomes

PURPOSE

To create a cut-off point for hyperextension that best discriminates retear and to verify whether this cut-off point can predict retear regardless of other characteristics after primary anterior cruciate ligament (ACL) reconstruction with hamstrings autograft.

METHODS

A cohort of patients submitted to primary isolated ACL reconstruction with hamstrings autografts was retrospectively evaluated. Patients were stratified according to the degree of passive knee hyperextension measured in the normal contralateral knee. The following data were collected: patient age and sex, time from injury to surgery, knee hyperextension, KT-1000 and pivot-shift, associated meniscus injury, intra-articular graft size, follow-up time, graft failure, and postoperative Lysholm and subjective International Knee Documentation Committee scores.

RESULTS

Data from 457 patients were evaluated. Median age was 31 years. Thirty-two (7.0%) presented with retear. There was a significant difference in hyperextension between patients with and without retear (P < .001), with the cut-off point established by the receiver operating characteristic curve from 6.5°. Patients with greater hyperextension had a statistically greater frequency of women, longer injury time, greater intra-articular graft diameter, greater postoperative KT-1000, and greater frequency of retear, whereas the subjective International Knee Documentation Committee and Lysholm scores were statistically lower in patients with greater hyperextension. Only hyperextension showed a statistically significant association with re-rupture (P < .001). The odds of retear in patients with hyperextension greater than 6.5 was 14.65 times the odds of patients with hyperextension less than 6.5.

CONCLUSIONS

Patients with more than 6.5° of hyperextension are 14.6 times more likely to have a graft rupture than patients with lower hyperextension when submitted to ACL reconstruction with hamstring tendons. Also, they present worse knee stability by the KT-1000 test and worse functional outcomes. Therefore, patients with this degree of hyperextension should not have isolated reconstruction with hamstrings as their first choice.

LEVEL OF EVIDENCE

Level III, retrospective comparative prognostic trial.

Incidence of Convergence Between Distally and Anteriorly Oriented ALL Femoral Tunnels and ACL Femoral Tunnels in Combined ACL and ALL Reconstruction: 3-Dimensional Computed Tomography Analysis of 227 Patients

BACKGROUND

Adjusting the direction of the anterolateral ligament (ALL) femoral tunnel is suggested to avoid tunnel convergence during anterior cruciate ligament (ACL) reconstruction. Yet, there has been no in vivo clinical study reporting the effect of changing the direction of the ALL tunnel on the incidence of convergence with the ACL tunnel.

PURPOSE

To report the incidence of convergence between the ACL femoral tunnel and a distally and anteriorly directed ALL femoral tunnel and to determine a safe distal angle and anterior angle.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 227 patients undergoing concomitant ALL and anatomic single-bundle ACL reconstruction between January 2020 and December 2022 were retrospectively reviewed. The tunnel convergence rate, angular orientation of the tunnels, and distance between tunnels were obtained using postoperative computed tomography. The patients were grouped based on the direction of the ALL tunnel (transverse vs distal anterior) and the presence of tunnel convergence (convergence vs no convergence).

RESULTS

The overall tunnel convergence rate was 53.3% (121/227 patients). Tunnel convergence was observed less frequently in the distal anterior group (33.7%) than in the transverse group (65.2%) (P < .001). The no convergence group showed an ALL tunnel oriented more distally (20.2°± 11.1°) and anteriorly (19.5°± 10.2°) compared with the convergence group (8.7°± 6.5° and 6.9°± 5.3°, respectively) (P = .005 and P = .008, respectively). There were no cases of tunnel convergence for ALL tunnels >24.3° distally and >25.5° anteriorly. There was no difference in the angle of the ACL femoral tunnel between all groups.

CONCLUSION

A distally and anteriorly directed ALL femoral tunnel reduced the incidence of convergence with the ACL femoral tunnel. A distal angle >24.3° and an anterior angle >25.5° of an ALL tunnel are suggested to safely avoid convergence with the ACL tunnel.

Association of Concomitant MRI-Determined Anterolateral Complex Injury With Quantitative Measurements of Altered Rotational Tibiofemoral Position on MRI in Patients With ACL Injury

Background

Reduced graft failure rates have been reported after anterior cruciate ligament (ACL) reconstruction combined with anterolateral complex (ALC) augmentation. However, the preoperative diagnosis of concomitant ALC injury remains a clinical challenge.

Purpose

To identify the altered rotational tibiofemoral position on magnetic resonance imaging (MRI) in ACL-injured patients with concomitant ALC injury.

Study Design

Cross-sectional study; Level of evidence, 3.

Methods

Based on the evaluation of ALC abnormalities on MRI scans by experienced surgeons, 123 patients with nonchronic (<3 months) ACL injury confirmed by arthroscopy were included. The patients were divided into 2 groups-an ALC-injured group (n = 57) and an ALC-intact group (n = 66). The altered rotational tibiofemoral position was evaluated and compared by quantitatively measuring internal rotational tibial subluxation (IRTS) and axial internal tibial rotation (ITRa) on MRI. Multivariate logistic regression and receiver operating characteristic (ROC) analyses were performed to identify the factors associated with concomitant MRI-determined ALC injury.

Results

The ALC-injured group showed significantly increased IRTS (P < .001), ITRa (P < .001), lateral anterior tibial subluxation (ATS) (P < .001), and global ATS (GATS) (P = .002) compared with the ALC-intact group, while no significant difference in medial ATS (P = .810) was observed. A strong positive correlation was identified between IRTS and ITRa (rP = 0.809; P < .001). Multivariate analyses revealed that IRTS (P < .001) and GATS (P = .016) were associated factors for the presence of concomitant MRI-determined ALC injury. IRTS (area under the curve [AUC] = 0.734) was more strongly associated with the outcome than GATS (AUC = 0.658) in ROC analyses, suggesting a more significant internal rotational subluxation than anterior subluxation of the tibia. An IRTS threshold of 3.1 mm demonstrated a specificity of 84.2% for indicating the presence of concomitant MRI-determined ALC injury.

Conclusion

The presence of concomitant MRI-determined ALC injury in ACL-injured patients was associated with a significant increase in IRTS and ITRa compared with those with intact ALC, indicating that these MRI measurements of the altered rotational tibiofemoral position could serve as potential quantifiable indicators for identifying concomitant ALC injury in clinical practice.

Lateral Extra-Articular Tenodesis with Indirect Femoral Fixation Using an Anterior Cruciate Ligament Reconstruction Suspensory Device

BACKGROUND

The lateral extra-articular tenodesis (LET) procedure associated with anterior cruciate ligament (ACL) reconstruction can be considered in selected patients to diminish the risk of persistent rotatory instability and achieve a protective effect on the graft. Several techniques have been described in the literature to treat rotatory instability. Usually, a strip of the iliotibial band (ITB) is harvested from its middle while leaving the distal insertion, then passed underneath the lateral collateral ligament and fixed on the lateral aspect of the distal femur with various fixation methods such as staples, screws, anchors or extracortical suspensory devices. Despite their effectiveness, these fixation methods may be associated with complications such as lateral pain, over-constraint and tunnel convergence.

METHODS

This study presents a detailed surgical description of a new technique to perform an LET during ACL reconstruction with any type of graft fixing the ITB strip with the sutures of the ACL femoral button, comparing its pros and cons in relation to similar techniques found in the literature.

CONCLUSIONS

This technique represents a reproducible, easy to learn and inexpensive solution to perform a lateral extra-articular tenodesis associated with an ACL reconstruction using the high-resistance sutures of the femoral button.

Anterolateral augmentation procedures during anterior cruciate ligament reconstructions in skeletally immature patients: Scoping review of surgical techniques and outcomes

Purpose

Graft failure rates after anterior cruciate ligament reconstruction (ACLR) in children and adolescents are higher compared to adults. Anterolateral augmentation procedures have recently generated increased focus regarding their ability to reduce graft failure rates. Concerns in skeletally immatures are potential growth disturbances and overconstraint after anterolateral augmentation. The aim of this scoping review is to provide an overview of all current anterolateral augmentation procedures in skeletally immature patients and to discuss surgical techniques, clinical and biomechanical outcomes.

Methods

This scoping review was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) statement extension for scoping reviews. On 22 December 2022, an information specialist performed a systematic literature search in Cochrane, PubMed (Medline) and EMBASE databases. Inclusion criteria were anterolateral augmentation procedures, including lateral extra-articular tenodesis (LET) and anterolateral ligament reconstruction (ALLR), in combination with ACLR in skeletally immatures.

Results

Twenty studies were included after screening 1.485 abstracts. Seventeen studies describe LET techniques, four studies ALLR techniques and one study both techniques. Biomechanical data is scarce and shows conflicting results. Two studies compared ACLR with LET to ACLR in skeletally immatures with promising results in favour of the combined procedure. There were no differences in outcomes between LET and ALLR.

Conclusions

Several LET and ALLR techniques have been described for skeletally immature patients and the first clinical data on LET and ALLR is available, which showed promising results. Further research is necessary to evaluate the risk of growth disturbances and overconstraint in skeletally immatures.

Level of Evidence

Level IV.

Combined Anterior Cruciate Ligament and Anterolateral Ligament Reconstruction Using a Single Peroneus Longus Tendon Graft

The peroneus longus tendon seems a viable graft option for knee ligament reconstructions, with adequate biomechanical properties and low morbidity after harvesting. The objective of this article is to describe a combined anterior cruciate ligament and anterolateral ligament reconstruction technique using a single peroneus longus tendon graft harvested from the infra malleolar region to ensure sufficient length.

A Cadaveric Study of the Optimal Isometric Region on the Anterolateral Surface of the Knee in Anterolateral Ligament Reconstruction

OBJECTIVE

Isolated intra-articular anterior cruciate ligament (ACL) reconstruction is not capable of restoring instability in many cases leading some to recommend concomitant anterolateral ligament (ALL) reconstruction. The satisfactory fixation site and graft length change are crucial in ligament reconstruction to restore the ALL function and avoid some unwanted graft behavior. The purpose of this investigation is to determine the optimal isometric region on the anterolateral aspect of the knee for ALL reconstruction using a three-dimensional optical instrument and a suture similar to an intraoperative isometric test.

METHODS

Six freshly frozen cadaveric human knees were used in this study. Data regarding the anterolateral surface were obtained using an optical measurement system to create a three-dimensional model. Nine points were selected on the femur (F1-F9) and tibia (Ta-Ti) respectively. The three-dimensional length change between each pair of tibial and femoral points was measured during passive knee flexion from 0° to 90° in 15° increments. Subsequently, five femoral points (A-E) were selected from the lateral femur, located in different areas relative to the lateral femoral epicondyle, and three tibial reference points (T1-T3) were selected in the isometric test. The changes in the length between each pair of reference points were measured using sutures. The 95% confidence interval for the rate of length change was estimated using the mean and standard deviation of the maximum rate of length change at different flexion angles, and the data were expressed as the mean (95% confidence interval) and compared with the maximum acceptable rate of change (10%).

RESULTS

The maximum acceptable change rate for ligament reconstruction is 10%, and the mean maximum rates and the 95% confidence interval (CI) of length change for the point combinations were calculated. Among all the combined points measured using the optical measurement system and the suture, the qualified point combination for reconstruction was F3 (8mm posterior and 8mm proximal to the lateral femoral epicondyle)-Tb (8mm proximal to the midpoint between the center of Gerdy's tubercle and the fibula head), A (posterior and proximal to the lateral femoral epicondyle)-T2 (10mm below the joint line)and A-T3 (15 mm below the joint line). The position of F3-Tb and A-T2 are close to each other.

CONCLUSION

The most isometric area of the femur for ALL reconstruction was posterior and proximal to the lateral femoral epicondyle. We recommend that the initial location of the femoral point be set at 8 mm posterior and 8 mm proximal to the lateral femoral epicondyle and the tibial point at approximately 10 mm below the joint line, midway between Gerdy's tubercle and fibular head, and subsequently adjusted to the most satisfactory position according to the isometric test.

Lateral meniscal injury without medial meniscal injury indicates the existence of the Segond fracture in ACL-deficient knees

Background/Objective

The purpose of this study was to find factors indicating the occurrence of the Segond fracture, a specific type of anterolateral ligament injury.

Methods

From January 2015 to December 2017, we retrospectively reviewed the medical records of patients diagnosed with acute anterior cruciate ligament (ACL) injury who underwent reconstruction within 90 days of injury. Diagnosis of the Segond fracture was determined either by magnetic resonance imaging or plain radiographs. Factors examined were: age at surgery, sex, body mass index (kg/m2), status of menisci, and activities led to ACL injury. After univariate screening, multivariate logistic regression analyses were performed. Patients were divided into four groups based on the presence of lateral meniscal (LM) and/or medial meniscal (MM) injuries and compared with respect to the occurrence of Segond fractures.

Results

A total of 375 patients were included (163 males, 212 females), with mean age 25.8 years old. Among them, 22 of 375 (5.9 %) had a Segond fracture. We identified injured lateral menisci (adjusted odds ratio (aOR), 3.029; 95 % Confidence Interval (CI), 1.206-7.609; P = 0.018), intact medial menisci (aOR, 0.229; 95 % CI, 0.065-0.810; P = 0.022), and higher body mass index (aOR, 1.102; 95 % CI, 1.008-1.205; P = 0.034) as factors indicative of the occurrence of Segond fracture. LM injury without MM injury suggested the existence of a Segond fracture.

Conclusion

LM injury without a MM injury indicated the occurrence of a Segond fracture. Higher body mass index also increased the risk for Segond fracture occurrence.

Progress in research on and classification of surgical methods of arthroscopic reconstruction of the ACL and ALL using a shared tendon graft through the femoral tunnel

Anterior cruciate ligament (ACL) tear is a common clinical injury, and ACL reconstruction has reached a very mature stage. However, with the accumulation of cases, scholars have found that isolated ACL reconstruction may not completely solve the problem of knee rotational stability. With the increase in our understanding of knee joint structure, ACL combined with anterolateral ligament (ALL) reconstruction has become accepted by most scholars, and this operation has also achieved good clinical results. At present, there is no unified surgical method for ACL combined with ALL reconstruction. There are differences in bone tunnel location, reconstruction methods, and graft selection. Compared with the independent reconstruction of the ACL and ALL during the operation, shared tendon graft reconstruction of the ACL and ALL has the advantages of preserving tendon and avoiding tunnel convergence. So far, there is no relevant literature summarizing the reconstruction of the ACL and ALL with a shared tendon graft. This paper reviews the anatomic study of the ALL, the study of isometric points, surgical indications, and surgical methods and their classification for shared tendon graft reconstruction of the ACL and ALL.