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

Reliability of MRI Detection of Kaplan Fiber Injury in Pediatric and Adolescent Patients with ACL Tears

Background:

While studies have described Kaplan fiber (KF) injury in up to 60% of adults with anterior cruciate ligament (ACL) tears, the incidence of KF injury in the pediatric and adolescent population remains unknown.

Purpose:

To (1) determine the reliability of using magnetic resonance imaging (MRI) to identify KF injury in the pediatric and adolescent population and (2) define the incidence of KF injury in these patients with acute ACL injuries.

Study Design:

Cohort study (diagnosis); Level of evidence, 3.

Methods:

The authors retrospectively identified patients ≤18 years of age who underwent ACL reconstruction for acute tears between 2013 and 2020. All preoperative MRI scans were reviewed independently and in a blinded fashion by 2 musculoskeletal radiologists, who noted the presence of the KF complex and any evidence of injury; interrater reliability was assessed. Patient characteristics, time from injury to MRI, laterality, and concomitant ligamentous or meniscal injuries were recorded, and associations between patient or injury characteristics and KF integrity on MRI were assessed.

Results:

In total, 51 patients (mean age, 14.9 years) met the inclusion criteria. Of these, 27 patients were female and 31 sustained an injury to the right knee. With respect to KF integrity, radiologist 1 visualized KF injury in 29% of patients, while radiologist 2 visualized KF injury in 35% of patients. In 12% of cases for radiologist 1 and 6% of cases for radiologist 2, KFs were unable to be visualized at all. The overall percentage agreement between the 2 radiologists was 76.5% with a kappa statistic of 0.57 (moderate agreement). There were no significant associations found between the presence of KF injury and patient age, sex, laterality, body mass index, concomitant ligamentous injury, or meniscal injury. However, visualization of KF injury on MRI was associated with a shorter time from index injury to MRI (15 days vs 23 days; P = .044).

Conclusion:

Approximately one-third of pediatric and adolescent patients who underwent ACL reconstruction were found to have KF injuries. Standard preoperative MRI scans can reliably be used to visualize KF injury in the majority of pediatric and adolescent patients with ACL tears, especially when the MRI is performed in the acute setting.

Latin American formal consensus on the appropriate indications of extra-articular lateral procedures in primary anterior cruciate ligament reconstruction

OBJECTIVES

To create a practice guideline for the appropriate indications of an extra-articular procedure in primary anterior cruciate ligament reconstruction (ACLR).

METHODS

The formal consensus method described by the Haute Autorité de Santé was used. The Latin American Society of Arthroscopy, Articular Replacement, and Sports Injuries (SLARD) recruited three groups of experts on ACLR. Initially, the steering group, consisting of eight surgeons, performed a systematic review of the literature and elaborated on 192 scenarios for primary ACLR. The rating group, composed of 23 surgeons, rated each scenario in two rounds, with an in-between in-person meeting for discussion. Median scores and agreement levels were estimated to classify each scenario as inappropriate, uncertain or appropriate for adding anterolateral reconstruction. Finally, the lecture group, consisting of 10 surgeons, revised each stage of the method, results and interpretation.

RESULTS

Of the scenarios, 11.97% were rated as appropriate for adding an extra-articular lateral procedure, 7.81% as inappropriate and 80.21% as uncertain. The key recommendations for the addition of extra-articular lateral techniques were as follows: it is appropriate when the patient is under 25 years of age, has high-grade physical examination findings, practises a pivoting sport and has hyperlaxity; meanwhile, it is inappropriate when the patient has low-grade physical examination findings, has normal laxity and does not practise a pivoting sport.

CONCLUSIONS

The appropriate indications of extra-articular lateral procedures in primary ACLR were determined on the basis of the best available evidence and expert opinion following a formal consensus method.

LEVEL OF EVIDENCE

V.

Graft choices for anterolateral ligament knee reconstruction surgery: Current concepts

The anterolateral ligament (ALL) is a primary structure of the anterolateral complex of the knee that contributes to internal rotational stability of the joint. Injury of the ALL is commonly associated with rupture of the anterior cruciate ligament. If left untreated, ALL lesions may lead to residual anterolateral rotational instability of the knee after anterior cruciate ligament reconstruction, which is a common cause of anterior cruciate ligament graft failure. The function of the ALL can be restored by lateral extraarticular tenodesis or anterolateral ligament reconstruction (ALLR). In the lateral extraarticular tenodesis procedure, a strip of the iliotibial band is placed in a non-anatomical position to restrain the internal rotation of the tibia, while in ALLR, a free graft is fixed at the insertion points of the native ALL. Gracilis and semitendinosus grafts have mainly been utilized for ALLR, but other autografts have also been suggested. Furthermore, allografts and synthetic grafts have been applied to minimize donor-site morbidity and maximize the size and strength of the graft. Nevertheless, there has been no strong evidence to fully support one method over another thus far. The present review presents a detailed description of the graft choices for ALLR and the current literature available in regard to the effectiveness and outcomes of published surgical techniques.

Anterolateral complex of the knee: State of the art

Rotatory instability of the knee represents the main reason for failure and poor clinical outcomes regarding anterior cruciate ligament (ACL) reconstruction techniques. It is now clear that the anterolateral complex (ALC) of the knee possesses a fundamental role, in association with the ACL, in controlling internal rotation. Over the past decade, ever since the anterolateral ligament has been identified and described as a distinct structure, there has been a renewed interest in the scientific community about the whole ALC: Lateral extra-articular tenodesis have made a comeback in association with ACL reconstructions to improve functional outcomes, reducing the risks of graft failure and associated injuries. Modern ACL reconstruction surgery must therefore investigate residual instability and proceed, when necessary, to extra-articular techniques, whether functional tenodesis or anatomical reconstruction.This review aims to investigate the latest anatomical and histological descriptions, and the role in rotational control and knee biomechanics of the ALC and its components. The diagnostic tools for its identification, different reconstruction techniques, and possible surgical indications are described.. In addition, clinical and functional results available in the literature are reported.

Differentiation in Posterior Tibial Slope by Sex, Age, and Race: A Cadaveric Study Utilizing 3-Dimensional Computerized Tomography

BACKGROUND

Posterior tibial slope (PTS) has recently gained increased attention for its possible role in anterior cruciate ligament and posterior cruciate ligament injury. The possible differences among age, sex, and ethnicity in PTS have not yet been reported.

PURPOSE

To describe demographic variances of proximal tibial anatomy and to detect differences in regard to ethnicity, sex, and age.

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

In total, 250 cadaveric specimens with full-body computerized tomography scans from the New Mexico Descendant Imaging Database were randomly selected (inclusion/exclusion criteria: older than 18 years, complete imaging of the knee without previous surgery or arthroplasty) and reviewed by 3 independent observers measuring medial posterior tibial slope (MPTS), lateral posterior tibial slope (LPTS), and global posterior tibial slope (PTS), which was calculated as the mean of the MPTS and LPTS. Individuals were evenly divided among male and female and ethnicities/races: African American/Black, Asian American, Hispanic, Native American, and White. Intraclass correlation coefficient was calculated for interobserver reliability and analysis of variance statistical testing to determine statistical significance between groups. Fisher exact test was also used to understand PTS differences among ethnicities when looking at clinically significant values for potential ligamentous injury.

RESULTS

Measurements were obtained from 250 specimens with a mean age of 49.4 years (range, 19 to 103 years). The mean PTS was 8.92° (range, -9.4° to 14.95°). Asian Americans had a 1.7° greater mean MPTS than Whites (P = .016), and African Americans/Blacks had a 1.6° greater mean PTS than Whites (P = .022). No difference in mean PTS was seen between age and sex. When looking at clinically significant PTS, 61 (24.4%) individuals had tibial slopes <6° or >12°, 32 (12.8%) and 29 (11.6%), respectively. Statistically significant differences were seen among ethnicities with PTS <6° (P = .017) but not with PTS >12° (P = .106). No sex-based differences were seen in the percentage of specimens with a PTS of >12° or <6°.

CONCLUSION

Among ethnicities, African Americans/Blacks and Asian Americans have increased PTS in comparison with Whites. Nearly 25% of individuals have clinically significant slopes of <6° or >12°, with no difference in tibial slope among sex or age groups.

Controversies in ACL revision surgery: Italian expert group consensus and state of the art

Background

Revision ACL reconstruction is a complex topic with many controversies and not-easy-to-make decisions. The authors’ aim is to provide some feasible advice that can be applied in daily clinical practice with the goal of facilitating the decision-making process and improving the outcomes of patients subjected to revision ACL reconstruction.

Methods

A national survey with seven questions about the most controversial topics in revision ACL reconstruction was emailed to members of two societies: SIOT and SIAGASCOT. The participants’ answers were collected, the most recent literature was analyzed, and a consensus was created by the authors, according to their long-term surgical experience.

Conclusions

The decision-making process in revision ACL reconstruction starts with a standardized imaging protocol (weight-bearing radiographs, CT scan, and MRI). One-stage surgery is indicated in almost all cases (exceptions are severe tunnel enlargement and infection), while the choice of graft depends on the previously used graft and the dimensions of the tunnels, with better clinical outcomes obtained for autografts. Additional procedures such as lateral extra-articular tenodesis in high-grade pivot-shift knees, biplanar HTO in the case of severe coronal malalignment, and meniscal suture improve the clinical outcome and should be considered case by case.

Level of evidence

V (Expert opinion).

Factors affecting return to play and graft re-rupture after primary ACL reconstruction in professional footballers

PURPOSE

Modern ACL reconstruction (ACL-R) techniques have led to improved outcomes in professional footballers. The aim of this study was to identify and assess patient, surgical and post-operative factors that affected rates and time to return to play (RTP) as well as ACL re-rupture rates.

METHODS

A retrospective review of consecutive ACL-R undertaken in professional footballers between 2005 and 2018.

RESULTS

Two-hundred and thirty-two knees in 215 professional footballers (17 bilateral) were included. 205 (88.9%) were male and average age at surgery was 23.3 ± 4.4 years. Two-hundred and twenty-two (96.1%) returned to professional football, with 209 (90.1%) returning to the same or higher Tegner level. Subgroup analysis revealed three factors that independently affected RTP rate: (1) Players under 25 years had a higher rate of RTP (99.3% vs 90.2%. p = 0.001); (2) a subsequent operation prior to RTP decreased RTP rate from 98.2 to 89.7% (p = 0.009).; (3) undergoing meniscal surgery at ACL-R decreased RTP rate (p = 0.002). The mean time to RTP from surgery was 10.5 ± 3.6 months. Factors found to increase RTP time included age under 25 (11.0 vs 9.7 months, p = 0.005), recurrent effusions (11.4 vs 10.2 months, p = 0.035), and medial meniscal repair at ACL-R compared to meniscectomy (12.5 vs 9.6 months, p = 0.022). The surgical technique varied over the study period in relation to graft type, femoral tunnel position and addition of lateral extra-articular tenodesis (LET). Overall, the re-rupture rate was 8.2% at 2 years. Patella tendon autograft in an anteromedial bundle femoral tunnel position with addition of LET has the lowest re-rupture rate (2.0%).

CONCLUSION

Primary ACL-R in professional footballers yields high rates of RTP (96.1%), with 90.1% at the same level or higher, at a mean 10.5 months. Patients under 25 years not only had a significantly higher RTP rate, but also had a lengthier period of rehabilitation.

LEVEL OF EVIDENCE

Level IV.

Suture Hook Versus All-Inside Repair for Longitudinal Tears of the Posterior Horn of the Medial Meniscus Concomitant to Anterior Cruciate Ligament Reconstruction: A Matched-Pair Analysis From the SANTI Study Group

BACKGROUND

Secondary meniscectomy rates after repair of longitudinal tears of the posterior horn of the medial meniscus (PHMM) performed concomitantly with anterior cruciate ligament reconstruction (ACLR) are reported to be as high as 25% with an all inside repair technique. Posteromedial portal suture hook repair is an emerging technique; however, it is unknown whether it confers a significantly reduced secondary meniscectomy rate compared with the current gold standard.

PURPOSE/HYPOTHESIS

The primary objective of this study was to compare the secondary meniscectomy rates of suture hook repair and all inside repair for longitudinal tears of the PHMM performed concomitant to ACLR. The secondary outcome was to determine the risk factors associated with the failure of the repair. It was hypothesized that repair with an all inside device would be associated with higher secondary meniscectomy rates when compared with suture hook repair and that concomitant anterolateral ligament reconstruction (ALLR) would confer improved meniscal repair survivorship.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients with longitudinal tears of the PHMM who underwent meniscal repair during primary ACLR between January 2011 and December 2015 at our institution were eligible for the study. Patients undergoing suture hook repair were propensity matched in a 1:1 ratio to patients who underwent all inside repair. At the end of the study period, secondary meniscectomy rates were determined.

RESULTS

The study population comprised 237 matched pairs. The mean follow up was 97.7 ± 17.3 months. Patients who underwent an all inside repair had a >2-fold higher failure rate compared with patients who underwent suture hook repair through a posteromedial portal (31.2% vs 15.6%; P = .0003). Patients in the suture hook repair group undergoing additional ALLR demonstrated a >3-fold higher meniscal repair survival rate compared with all other subgroups (P = .0014). This association was not seen in the all inside repair group. The only statistically significant risk factor for meniscal repair failure was the suture repair technique (hazard ratio, 2.133 [95% CI, 1.383-3.292]; P = .0008).

CONCLUSION

Suture hook repair through a posteromedial portal is associated with a significantly lower secondary meniscectomy rate when compared with the all inside meniscal repair of longitudinal tears of the PHMM performed at the time of ACLR. Furthermore, patients in the suture hook repair group who underwent an additional ALLR had a significantly better meniscal repair survivorship compared with all other subgroups.

Magnetic resonance imaging does not reliably detect Kaplan fiber injury in the setting of anterior cruciate ligament tear

PURPOSE

There has been a continued effort to better understand the role Kaplan fiber injury plays in persistent instability following ACL tears. However, the prevalence of these injuries remains poorly understood. Therefore, the purpose of this study was to define the prevalence of Kaplan fiber injury in the setting of complete anterior cruciate ligament tear using a commonly used grading system for assessing ligament injuries. The inter-rater reliability of this commonly used grading system and the relationship between Kaplan fiber injury and injury to other structures commonly found in conjunction with ACL tears was also evaluated.

METHODS

All isolated, complete anterior cruciate ligament tears confirmed on magnetic resonance imaging within 90 days of injury between 2014 and 2020 at a single institution were included for analysis. Each scan was read by two, fellowship-trained musculoskeletal radiologists. Kaplan fiber injury was evaluated using a previously described grading scheme. Kappa, [Formula: see text], of inter-rater agreement was determined for all magnetic resonance image scans. Kruskal Wallis test was performed to assess for associations between Kaplan fiber injury and magnet strength (1.5 T vs. 3.0 T), patient gender, the presence of medial and/or lateral meniscal tears, and/or posterolateral tibial bone bruise.

RESULTS

Between 2014 and 2020, 131 patients (94 males, 37 females) with a complete anterior cruciate ligament tear were included in the final analysis. The mean age of the cohort was 27.8 ± 6.8 years. Kaplan fiber injuries were identified in 51 of 131 (38.9%, CI 31.0-47.5%) scans with complete anterior cruciate ligament injuries (Grade 1: 28, Grade 2: 18, and Grade 3: 5). Inter-rater agreement for Kaplan fiber injury was fair ([Formula: see text] with 43 (32.8%) scans requiring third reviewer adjudication. There were no significant associations between Kaplan fiber injury and gender, magnet strength, meniscal tears, or posterolateral tibial bone bruise.

CONCLUSION

The prevalence of Kaplan fiber injuries was comparable to previously described rates; however, the classification system used to report Kaplan fiber injury was associated with low inter-rater reliability. The presence of Kaplan fiber injury was not associated with other injuries commonly observed in conjunction with ACL tear. The previously proposed Kaplan fiber injury classification system is not reproducible nor is it likely to aid surgeons in distinguishing higher grades of rotatory knee instability.

LEVEL OF EVIDENCE

Level IV.

Risk of Graft Rupture After Adding a Lateral Extra-articular Procedure at the Time of ACL Reconstruction: A Retrospective Comparative Study of Elite Alpine Skiers From the French National Team

BACKGROUND

Elite alpine skiing is associated with a particularly high risk of anterior cruciate ligament (ACL) injuries, including graft ruptures. Despite a considerable focus on prevention, a reduction in injury rates has not been observed since the 1980s.

PURPOSE

To determine whether elite alpine skiers undergoing ACL reconstruction (ACLR) with a lateral extra-articular procedure (LEAP) had a lower rate of ACL graft rupture when compared with those who underwent isolated ACLR.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Elite skiers from the French ski team who had undergone ACLR, with or without a LEAP, and had a minimum follow-up of 2 years were identified from the national ski team database. Rates of secondary ACL injury were determined via interrogation of the database, review of medical notes, and a final telemedicine interview. A multivariable analysis using the penalized Cox model was performed to explore the relationship among graft rupture, surgical procedure type, and any potential explanatory variables.

RESULTS

Among 81 ACLR procedures analyzed, 50 were isolated and 31 were combined with a LEAP, which was performed using modified Lemaire or anterolateral ligament reconstruction. Graft rupture rates were 34.0% in the isolated ACLR group and 6.5% in the ACLR + LEAP group. Multivariable analysis demonstrated that adding a LEAP was associated with a significant reduction in risk of ACL graft rupture when compared with isolated ACLR (hazard ratio [HR], 5.286 [95% CI, 1.068-26.149]; P = .0412). Age (HR, 1.114; P = .1157), sex (HR, 1.573; P = .3743), and ACL graft type (HR, 1.417; P = .5394) were not significant risk factors.

CONCLUSION

Combined ACLR and LEAP were associated with a significant reduction in the rate of ACL graft rupture in elite alpine ski athletes. Those treated with isolated ACLR remain at extremely high risk of a second ACL injury.

Anterior cruciate ligament reconstruction with lateral plasty restores anterior-posterior laxity in the case of concurrent partial medial meniscectomy

PURPOSE

To evaluate the in vivo knee laxity in the presence of a partial medial meniscectomy before and after a single-bundle ACL reconstruction with a lateral plasty (SBLP) and to compare it with the knee laxity after a single-bundle ACL reconstruction (SB).

METHODS

One-hundred and one patients with ACL tear were enrolled in the study and grouped according to the surgical technique and the meniscus treatment: regarding the SBLP technique (n = 55), 31 patients underwent isolated ACL reconstruction ("SBLP Isolated ACL Group"), while 24 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SBLP ACL + MM Group"); regarding the SB technique (n = 46), 33 patients underwent isolated ACL reconstruction ("SB Isolated ACL Group"), while 13 patients underwent combined ACL reconstruction and partial medial meniscectomy ("SB ACL + MM Group"). Anterior-posterior clinical laxity at 30° (AP30) and 90° (AP90) of knee flexion was quantified before and after surgery through a surgical navigation system dedicated to kinematic assessment.

RESULTS

In the ACL-deficient status, the antero-posterior laxity was significantly higher in the presence of a combined MM in both the AP30 and the AP90, with no differences between the two surgical techniques. After the ACL reconstruction, both AP30 and AP90 translations decreased significantly (p < 0.0001) compared to the ACL-deficient status. No differences were found for AP30 and AP90 between SBLP Isolated ACL and SBLP + MM groups, while a significantly higher AP90 translation was found for the SB + MM group compared to the SB Isolated ACL group. Moreover, the AP90 translation in the SB ACL + MM group was significantly higher than the one of the other three groups, i.e., SBLP ACL + MM, SB, and SBLP Isolated ACL group.

CONCLUSION

The ACL reconstruction with lateral plasty reduced the AP knee laxity caused by the medial meniscectomy in the context of an ACL surgery.

LEVEL OF EVIDENCE

Level II.

Postural control during single leg stance in individuals with clinical indication for combined reconstruction of the anterior cruciate and the anterolateral ligaments of the knee: a cross-sectional study

Background

Several studies have shown persistent postural control deficits and rotatory instability in patients after isolated Anterior Cruciate Ligament (ACL) reconstruction. There is evidence to support that the Anterolateral Ligament (ALL) plays an important role in the remaining anterolateral rotatory laxity of the knee. There are no further evidences in order to understand how patients with a combined ACL + ALL reconstruction surgery indication behave regarding postural control. The aim of this cross-sectional study was to assess if patients with a clinical indication for the combined ACL + ALL surgery showed a deficient postural control in single leg stance compared to subjects with a regular ACL reconstruction indication and to a control group.

Methods

An assessment of static postural control on single leg stance was performed on a force plate, with eyes open and closed, and the center of pressure (COP) displacement variables were analyzed: maximum and mean amplitude in anteroposterior (AP) and in mediolateral (ML) direction; mean velocity of displacement and area of displacement. Eighty-nine male individuals participated and were divided into 3 groups: ACL Group, ACL + ALL Group and Control Group.

Results

The ACL+ ALL Group showed significantly greater COP displacement in most variables in the injured leg for the eyes closed test, compared to the ACL Group, as detailed: Total ML displacement (9.8 ± 6.77 vs. 13.98 ± 6.64, p < 0.001); Mean ML displacement (2.58 ± 2.02 vs. 3.72 ± 1.99, p < 0.001); Total AP displacement (9.5 ± 3.97 vs. 11.7 ± 3.66, p = 0.001); Mean AP displacement (1.77 ± 0.87 vs. 2.27 ± 0.86, p = 0.001); Area of displacement (111.44 ± 127.3 vs. 183.69 ± 131.48, p < 0.001).

Conclusion

Subjects with a clinical indication for ACL + ALL combined reconstruction surgery showed increased COP displacement compared to patients with indication for an ACL isolated reconstruction surgery.

Three-Dimensional Reconstruction Algorithm-Based Magnetic Resonance Imaging Evaluation of Biomechanical Changes in Articular Cartilage in Patients after Anterior Cruciate Ligament Reconstruction

This study aimed to investigate the evaluation of biomechanical changes in articular cartilage in patients after anterior cruciate ligament (ACL) reconstruction by magnetic resonance imaging (MRI) based on a three-dimensional (3D) finite element model. The data of 90 patients undergoing arthroscopic ACL reconstruction in the hospital were collected and divided into the stable group (54 cases) and the unstable group (36 cases). A load of up to 134N was applied to the 3D finite element model, and the kinematics of knee flexion at 0°, 30°, 60°, and 90° were examined. The tibial anteversion, tibial rotation, and ACL/graft tension were recorded in the 3D finite element model, which was randomly divided into the normal group (intact group, n = 30), the ACL rupture group (deficient group, n = 30), and the anatomical reconstruction group (anatomical group, n = 30). When the graft was fixed at 0°, the anterior tibial translation at 30°, 60°, and 90° in the anatomic group was 8-19% higher than the normal value under 134 N anterior load. The tibial internal rotation in the anatomic group was 18% and 28% higher than the normal value at 30° and 90°. When the graft was fixed at 30°, the anterior tibial translation at 60° and 90° of the anatomic group was 15% higher than the normal value. The tibial internal rotation at 90° of the anatomic group was 16% higher than the normal value, and the above differences had statistical significance (P < 0.05). MRI images were used to assess the bone tunnel angle, and the statistical analysis by the independent-samples t-test showed that there were significant differences in the bone tunnel angle between the stable group and the unstable group (P < 0.05). Currently, based on the 3D finite element model, MRI can accurately evaluate the postoperative effect of anatomical ACL reconstruction in the position, diameter, and angle of tibial and femoral bone tunnels, which can be applied to clinical promotion.

Tibial internal rotation in combined anterior cruciate ligament and high-grade anterolateral ligament injury and its influence on ACL length

Background

Assessment of combined anterolateral ligament (ALL) and anterior cruciate ligament (ACL) injury remains challenging but of high importance as the ALL is a contributing stabilizer of tibial internal rotation. The effect of preoperative static tibial internal rotation on ACL -length remains unknown. The aim of the study was analyze the effect of tibial internal rotation on ACL length in single-bundle ACL reconstructions and to quantify tibial internal rotation in combined ACL and ALL injuries.

Methods

The effect of tibial internal rotation on ACL length was computed in a three-dimensional (3D) model of 10 healthy knees with 5° increments of tibial internal rotation from 0 to 30° resulting in 70 simulations. For each step ACL length was measured. ALL injury severity was graded by a blinded musculoskeletal radiologist in a retrospective analysis of 61 patients who underwent single-bundle ACL reconstruction. Preoperative tibial internal rotation was measured in magnetic resonance imaging (MRI) and its diagnostic performance was analyzed.

Results

ACL length linearly increased 0.7 ± 0.1 mm (2.1 ± 0.5% of initial length) per 5° of tibial internal rotation from 0 to 30° in each patient.

Seventeen patients (27.9%) had an intact ALL (grade 0), 10 (16.4%) a grade 1, 21 (34.4%) a grade 2 and 13 (21.3%) a grade 3 injury of the ALL. Patients with a combined ACL and ALL injury grade 3 had a median static tibial internal rotation of 8.8° (interquartile range (IQR): 8.3) compared to 5.6° (IQR: 6.6) in patients with an ALL injury (grade 0–2) (p = 0.03). A cut-off > 13.3° of tibial internal rotation predicted a high-grade ALL injury with a specificity of 92%, a sensitivity of 30%; area under the curve (AUC) 0.70 (95% CI: 0.54–0.85) (p = 0.03) and an accuracy of 79%.

Conclusion

ACL length linearly increases with tibial internal rotation from 0 to 30°. A combined ACL and high-grade ALL injury was associated with greater preoperative tibial internal rotation. This potentially contributes to unintentional graft laxity in ACL reconstructed patients, in particular with concomitant high-grade ALL tears.

Study design

Cohort study; Level of evidence, 3.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-022-05218-8.

Minimizing the risk of graft failure after anterior cruciate ligament reconstruction in athletes. A narrative review of the current evidence

Anterior cruciate ligament (ACL) tear is one of the most common sport-related injuries and the request for ACL reconstructions is increasing nowadays. Unfortunately, ACL graft failures are reported in up to 34.2% in athletes, representing a traumatic and career-threatening event. It can be convenient to understand the various risk factors for ACL failure, in order to properly inform the patients about the expected outcomes and to minimize the chance of poor results. In literature, a multitude of studies have been performed on the failure risks after ACL reconstruction, but the huge amount of data may generate much confusion.The aim of this review is to resume the data collected from literature on the risk of graft failure after ACL reconstruction in athletes, focusing on the following three key points: individuate the predisposing factors to ACL reconstruction failure, analyze surgical aspects which may have significant impact on outcomes, highlight the current criteria regarding safe return to sport after ACL reconstruction.

Does anterolateral ligament internal bracing improve the outcomes of anterior cruciate ligament reconstruction in patients with generalized joint hypermobility?

BACKGROUND

Generalized joint hypermobility (GJH) is a risk factor for anterior cruciate ligament (ACL) injury and ACL graft failure and is considered an indication for anterolateral ligament (ALL) reconstruction. The aim of this retrospective study was to compare functional outcomes, rupture rates, and residual instability in patients with GJH undergoing isolated ACL reconstruction or combined ACL reconstruction and ALL augmentation with internal bracing (ALL-IB).

METHODS

Sixty-eight patients with GJH and unilateral ACL injury were randomly assigned to undergo either isolated ACL reconstruction (Group 1) or combined ACL reconstruction and ALL-IB (Group 2). The patients were evaluated pre- and postoperatively; their medical histories; physical examination results; anterior knee translation, as measured using the KT-1000 arthrometer; and scores of validated knee assessments were recorded.

RESULTS

Groups 1 and 2 consisted of 37 and 31 patients, respectively. The mean follow-up was 30.1±4.1 and 28.1±2.9 months, respectively. In the final evaluation, the patients in Group 2 showed better rotational stability, as evaluated by the pivot-shift test (p=0.013); better anteroposterior stability, as evaluated by KT-1000 arthrometry (p=0.001); similar function (p=0.14 for the Lysholm, p=0.11 for the Cincinnati, and p=0.19 for the International Knee Documentation Committee subjective score); and failure rate (p=0.41).

CONCLUSION

The functional outcomes were similar between the groups. The stability outcomes after combined ACL and ALL-IB were better than those after isolated ACL reconstruction in patients with GJH. However, the technique and its results need to be validated in larger patient series and prospective randomized controlled trials.

Prevalence of Segond fractures associated with anterior cruciate ligament injuries and their influence on knee joint stability; A case-control study

Background

The purpose of this study was to determine the prevalence of Segond fractures and to compare knee stability between patients undergoing primary anterior cruciate ligament (ACL) reconstruction with and without Segond fractures pre- and postoperatively.

Methods

A total of 712 patients who underwent primary ACL reconstruction between 2014 and 2019. Exclusion criteria included patients with multi-ligament knee injuries, skeletally immature patients, osteoarthritis in the knee, combined surgery of high tibial osteotomy, lack of data, and loss to follow-up for at least 2 years. Segond fractures were confirmed using plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI). Patients with Segond fractures were classified into Group S and without Segond fractures into Group N. Pre- and postoperative Lachman grades, pivot-shift grades, and assessment of side-to-side differences in anterior stability were evaluated.

Results

Five hundred and forty patients included in this study. There were 22 patients with Segond fractures. Of these, all 22 cases (4.1%) were identified on CT, but only 20 cases (3.7%) were identified on MRI and 18 cases (3.3%) on plain radiographs. There was no significant difference in preoperative Lachman grade or pivot-shift grade between Groups S and N (p = 0.662, p = 0.677, respectively). There was no significant difference in postoperative Lachman grade or pivot-shift grade between Groups S and N (p = 0.685, p = 0.390, respectively). There were no significant differences in preoperative (p = 0.398) or postoperative (p = 0.546) side-to-side differences of anterior stability between Groups S and N.

Conclusions

Segond fractures were confirmed in 4.1% of the cases on CT scans among patients undergoing primary ACL reconstruction. Segond fractures did not affect preoperative or 2-year follow-up evaluations of knee stability. From these results, we concluded that Segond fractures did not affect the clinical outcomes of the primary ACL reconstruction and that it may not be necessary to treat Segond fractures.

Reliability of a Novel Automatic Knee Arthrometer for Measuring Knee Laxity After Anterior Cruciate Ligament Ruptures

Background:

The accuracy of existing devices for measuring knee laxity is adversely affected by examiner reliability.

Purpose:

To compare the accuracy of a novel automatic knee arthrometer (AKA) to that of the KT-2000 arthrometer for measuring knee laxity after anterior cruciate ligament (ACL) ruptures.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

We measured anterior displacement and the anterior displacement difference (ADD) at 134 N of anterior force in 221 healthy volunteers and 200 patients with ACL ruptures. All trials were performed by the same 2 examiners. We first analyzed the effects of examiner, side assessed, and device type using the intraclass correlation coefficient (ICC), t test, and F test. We then used the receiver operating characteristic curve to compare the diagnostic value of the measurements between devices.

Results:

In repeated measurements for a single healthy volunteer, there were no differences in the variance of the measurements between sides according to the AKA (standard deviation of right vs left knee for examiner A: 0.43 vs 0.58 mm, respectively [P = .39]; for examiner B: 0.49 vs 0.77 mm, respectively [P = .81]), while the KT-2000 measurements showed differences (standard deviation of right vs left knee for examiner A: 1.47 vs 0.80 mm, respectively [P = .02]; for examiner B: 1.78 vs 0.91 mm, respectively [P = .01]). The ADD assessed by the AKA was not significantly different between examiners A and B (0.50 vs 0.75 mm, respectively; P = .27; ICC = 0.83), but the KT-2000 showed a difference (1.07 vs 2.01 mm, respectively; P = .01; ICC = 0.55). The ADD of 20 healthy volunteers assessed by the AKA was less than that by the KT-2000 (0.98 vs 1.41 mm, respectively; P = .04). When comparing the diagnostic value of the 2 devices in the sample of 200 patients with ACL ruptures and 200 healthy controls, the area under the receiver operating characteristic curve for the AKA was larger than that for the KT-2000 (0.93 vs 0.87, respectively; P ≤ .01), and the threshold values were 1.75 and 2.73 mm, respectively.

Conclusion:

The AKA can be used to determine the degree of knee laxity in ACL injuries and to provide indications for treatment.

Femoral Positioning of the Anterolateral Ligament Graft With and Without Ultrasound Location of the Lateral Epicondyle

BACKGROUND

In anterior cruciate ligament (ACL) reconstruction with anterolateral ligament (ALL) reconstruction, precise positioning of the ALL graft on the femur and tibia is key to achieve rotational control. The lateral femoral epicondyle is often used as a reference point for positioning of the ALL graft and can be located by palpation or with ultrasound guidance.

PURPOSE

To compare the ALL graft positioning on the femoral side between an ultrasound-guided technique and a palpation technique for the location of the lateral epicondyle.

STUDY DESIGN

Cohort study; Level of evidence, 2.

METHODS

A total of 120 patients receiving a primary combined ACL and ALL reconstruction between June and December 2019 were included. The location of the lateral epicondyle was determined by palpation in the palpation group (n = 60) and with preoperative ultrasound guidance in the ultrasound group (n = 60). Groups were comparable in age, sex, body mass index (BMI), and operated side. The planned positioning of the femoral ALL graft was proximal and posterior to the lateral epicondyle. The effective positioning of the femoral ALL graft was evaluated on postoperative lateral radiographs. The primary outcome was location of the graft in a 10-mm quadrant posterior and proximal to the lateral epicondyle. Results were analyzed in 2 subgroups according to BMI.

RESULTS

All 60 anterolateral grafts (100%) in the ultrasound group were positioned in a 10-mm quadrant posterior and proximal to the lateral epicondyle, as opposed to 52 (87%) in the palpation group (P = .006). Errors in graft positioning with palpation occurred in overweight patients (BMI >25) as well as nonoverweight patients (P = .3).

CONCLUSION

Femoral positioning of the ALL graft posterior and proximal to the lateral epicondyle is more reproducible with ultrasound guidance when compared with palpation alone, regardless of BMI.

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

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction (ACLR) has higher failure rates in young active patients returning to sports as compared with older, less active individuals. Augmentation of ACLR with an anterolateral procedure has been shown to reduce failure rates; however, indications for this procedure have yet to be clearly defined.

PURPOSE/HYPOTHESIS

The purpose of this study was to identify predictors of ACL graft failure in high-risk patients and determine key indications for when hamstring ACLR should be augmented by a lateral extra-articular tenodesis (LET). We hypothesized that different preoperative characteristics and surgical variables may be associated with graft failure characterized by asymmetric pivot shift and graft rupture.

STUDY DESIGN

Case-control study; Level of evidence, 3.

METHODS

Data were obtained from the Stability 1 Study, a multicenter randomized controlled trial of young active patients undergoing autologous hamstring ACLR with or without a LET. We performed 2 multivariable logistic regression analyses, with asymmetric pivot shift and graft rupture as the dependent variables. The following were included as predictors: LET, age, sex, graft diameter, tear chronicity, preoperative high-grade knee laxity, preoperative hyperextension on the contralateral side, medial meniscal repair/excision, lateral meniscal repair/excision, posterior tibial slope angle, and return-to-sports exposure time and level.

RESULTS

Of the 618 patients in the Stability 1 Study, 568 with a mean age of 18.8 years (292 female; 51.4%) were included in this analysis. Asymmetric pivot shift occurred in 152 (26.8%) and graft rupture in 43 (7.6%). The addition of a LET (odds ratio [OR], 0.56; 95% CI, 0.37-0.83) and increased graft diameter (OR, 0.62; 95% CI, 0.44-0.87) were significantly associated with lower odds of asymmetric pivot shift. The addition of a LET (OR, 0.40; 95% CI, 0.18-0.91) and older age (OR, 0.83; 95% CI, 0.72-0.96) significantly reduced the odds of graft rupture, while greater tibial slope (OR, 1.15; 95% CI, 1.01-1.32), preoperative high-grade knee laxity (OR, 3.27; 95% CI, 1.45-7.41), and greater exposure time to sport (ie, earlier return to sport) (OR, 1.18; 95% CI, 1.08-1.29) were significantly associated with greater odds of rupture.

CONCLUSION

The addition of a LET and larger graft diameter were significantly associated with reduced odds of asymmetric pivot shift. Adding a LET was protective of graft rupture, while younger age, greater posterior tibial slope, high-grade knee laxity, and earlier return to sport were associated with increased odds of graft rupture. Orthopaedic surgeons should consider supplementing hamstring autograft ACLR with a LET in young active patients with morphological characteristics that make them at high risk of reinjury.

Anterolateral complex injuries occur in the majority of 'isolated' anterior cruciate ligament ruptures

PURPOSE

The anterolateral soft tissue envelope of the knee is frequently injured at the time of ACL rupture. This study aims to investigate the MRI injury patterns to the Anterolateral complex and their associations in patients with acute 'isolated ligament' ACL ruptures.

METHODS

Professional athletes who underwent ACL reconstruction for complete ACL rupture between 2015 and 2019 were included in this study. Patients' characteristics and intraoperative findings were retrieved from clinical and surgical documentation. Preoperative MRIs were evaluated and the injuries to respective structures of the Anterolateral complex and their associations were recorded.

RESULTS

Anterolateral complex injuries were noted in 63% of cases. The majority of injuries were to Kaplan Fibre (39% isolated injury and 19% combined with Anterolateral ligament injury). There was a very low incidence of isolated Anterolateral ligament injuries (2%). Kaplan Fibre injuries are associated with the presence of lateral femoral condyle bone oedema, and injuries to the superficial MCL, deep MCL, and ramp lesions. High grade pivot shift test was not associated with the presence of Kaplan Fibre or Anterolateral ligament injuries. Patients with an intact Anterolateral complex sustained injury to other knee structures (13% to medial ligament complex, 14% to medial meniscus, and 16% to lateral meniscus).

CONCLUSION

There is a high incidence of concomitant Anterolateral complex injuries in combination with ACL ruptures, with Kaplan Fibre (and therefore the deep capsulo-osseous layer of the iliotibial band) being the most commonly injured structure. Anterolateral ligament injuries occur much less frequently. These findings reinforce the importance of considering the presence of, and if necessary, treating injuries to structures other than the ACL, as a truly isolated ACL injury is rare.

Journey around the Notch: A Systematic Review on the History of ACL Reconstruction in the United States

The evolution of anterior cruciate ligament (ACL) surgery, seemingly circular at times, informs and provides context for past and current controversies in ACL management. The purpose of this systematic review is to objectively summarize the historical course of ACL reconstruction and repair in the United States over the last 40 years. Femoral tunnel drilling and graft selection have evolved dramatically over the last few decades. An initial focus on restoring ACL anatomy was for a period sacrificed for decreased operative morbidity. However, recent developments in operative techniques aim to restore ACL anatomy while also achieving minimal operative morbidity. Despite this historically iterative process, there remains no perfect choice for the treatment of ACL tears. Continued research on ACL repair, anatomic graft placement, graft choice, and augmentation will help our patients over the next generation.

The Cadaveric Studies and the Definition of the Antero-Lateral Ligament of the Knee: From the Anatomical Features to the Patient-Specific Reconstruction Surgical Techniques

Cadaver studies represented a milestone in surgical orthopaedic research, and still today they play a crucial role in the achievement of new knowledge about joint disease behaviour and treatment. In this review, an overview of the cadaver studies available in the literature about the anatomy, role, and treatment of the antero-lateral ligament (ALL) of the knee was performed. The aim of the review was to describe and gain more insight into the part of in vitro study in understanding knee joint anatomy and biomechanics, and in developing surgical reconstruction techniques. The findings of the review showed that cadaver studies had, and will continue to have, a key role in the research of knee joint biomechanics and surgical reconstruction. Moreover, they represent a powerful tool to develop and test new devices which could be useful in clinical and surgical practice.

The modifying factors that help improve anterior cruciate ligament reconstruction rehabilitation: A narrative review

BACKGROUND

The goal of a rehabilitation programme after anterior cruciate ligament (ACL) reconstruction is to manage a patient's goals and expectations (i.e., returning to physical activities and sports) while minimizing the risk of new injury, particularly a new ACL injury. Although general rehabilitation programmes have been proposed, some factors can lead to adapting each programme to each patient.

OBJECTIVE

To describe how different variables, including surgical techniques, sports participation, psycho-social and contextual factors can modify the rehabilitation programme.

METHODS

We performed a narrative review with input from experts in the field (level of evidence 5).

CONCLUSIONS

Modifying factors of the ACL rehabilitation programme are related to the initial lesion or surgery, to sports, or to psychological or social aspects. Regarding the type of graft, the rehabilitation is mainly different in the early postoperative phase; the other phases are not graft-based but rather goal-based rehabilitation. Depending on the meniscal or cartilage repair, the rehabilitation protocol will initially take priority over the anterior cruciate ligament reconstruction protocol. The ACL reconstruction rehabilitation programme should meet the requirements of the anticipated sports, to optimize the athlete's ability to return to the expected level and minimize the risk of reinjury. Psycho-social and contextual factors must also be considered in rehabilitation care to individualize and optimize each patient's programme.

Tibial Sagittal Slope in Anterior Cruciate Ligament Injury and Treatment

Although anterior cruciate ligament reconstruction (ACLR) is a generally successful procedure, failure is still relatively common. An increased posterior tibial slope (PTS) has been shown to increase the anterior position of the tibia relative to the femur at rest and under load in biomechanical studies. Increased PTS has also been shown to increase forces on the native and reconstructed ACL. Clinical studies have demonstrated elevated PTS in patients with failed ACLR and multiple failed ACLR, compared with control subjects. Anterior closing-wedge osteotomies have been shown to decrease PTS and may be indicated in patients who have failed ACLR with a PTS of ≥12°. Available clinical data suggest that the procedure is safe and effective, although evidence is limited to case series. This article presents the relevant biomechanics, clinical observational data on the effects of increased PTS, and an algorithm for evaluating and treating patients with a steep PTS.

Anterolateral Ligament Reconstruction Improves Anteroposterior Stability As Well As Rotational Stability in Revision Anterior Cruciate Ligament Reconstruction with High-Grade Pivot Shift

This study aimed to investigate the effect of anterolateral ligament reconstruction (ALLR) in revision anterior cruciate ligament reconstruction (ACLR) with high-grade pivot shift. The hypothesis was that revision ACLR combined with ALLR (RACLR with ALLR group) would show superior clinical outcomes to those of isolated revision ACLR. We retrospectively evaluated consecutive patients who underwent revision ACLR (RACLR) combined with ALLR between October 2015 and January 2017. The indication for combination of ALLR with revision ACLR was failed ACLR with ≥G2 pivot-shift instability. The control group included patients who underwent isolated revision ACLR (isolated RACLR group) for the same indication between July 2013 and September 2015. Exclusion criteria were ≤G1 pivot-shift instability, multiple ligament reconstruction, bilateral ligament injury, double-bundle reconstruction, insufficient medical records, postoperative infection, and follow-up loss at postoperative 2 years. Clinical scores, stability tests, and failure rates were compared between groups at the 2-year follow-up. The RACLR with ALLR group had 18 patients (mean age, 32.9 ± 10.8 years) and the RACLR group had 21 patients (mean age, 29.6 ± 10.2 years). Clinical scores at the 2-year follow-up showed no significant differences between groups. However, the RACLR with ALLR group showed better stability in the Lachman test (p = 0.005), pivot-shift test (p = 0.030), and side-to-side difference in stress radiographs (3.9 ± 3.0 mm vs. 5.9 ± 2.8 mm, p = 0.018) than the isolated RACLR group. The RACLR with ALLR group had two failures (11.1%), and the RACLR group had three failures (14.3%). In conclusion, ALLR in revision ACLR with high-grade pivot shift improves anteroposterior stability as well as rotational stability at 2-year follow-up. Therefore, ALLR is recommended with revision ACLR, especially in patients with high-grade pivot shift. This is a Level III, retrospective cohort review.

Clinical outcomes of combined anterior cruciate ligament and anterolateral ligament reconstruction: a systematic review and meta-analysis

OBJECTIVES

To compare the clinical outcomes of isolated anterior cruciate ligament (ACL) reconstruction with combined reconstruction of the ACL and anterolateral ligament (ALL) of the knee.

METHODS

A search was conducted on the PubMed, Medline, Google Scholar, EMBASE, and Cochrane library databases, in line with the PRISMA protocol. The indexation terms used were "anterior cruciate ligament" OR "acl" AND "anterolateral ligament" AND "reconstruction." Articles that compared patients submitted to combined ACL and ALL reconstruction with those submitted to isolated reconstruction of the ACL, with levels of evidence I, II, and III, were included. Studies with follow-up of less than 2 years and articles that did not use "anatomical" techniques for ALL reconstruction, such as extraarticular tenodesis, were excluded. A meta-analysis with R software was conducted, with a random effects model, presented as risk ratio (RR) or mean difference (MD), with a 95% confidence level (CI) and statistically significant at p < 0.05.

RESULTS

Ten articles were selected, with a total of 1495 patients, most of whom were men, of whom 674 submitted to ACL and ALL reconstruction and 821 to isolated ACL reconstruction. Combined ACL and ALL reconstruction exhibited a statistically significant advantage in residual pivot shift (RR 0.34, 95% CI 0.24-0.47, I² = 0%, p < 0.01), rerupture rate (RR 0.34, 95% CI 0.19-0.62, I² = 0%, p < 0.01), Lachman test (RR 0.59, 95% CI 0.40-0.86, I² = 21%, p < 0.01), and postoperative Lysholm score (MD 2.28, CI 95% 0.75-3.81, I² = 73%, p < 0.01).

CONCLUSIONS

Combined ACL and ALL reconstruction obtained better postoperative clinical outcomes when compared with isolated ACL reconstruction, especially in reducing residual pivot shift and rerupture rate.

High Incidence of Intra-articular Injuries With Segond Fractures of the Tibia in the Pediatric and Adolescent Population

BACKGROUND

Segond fractures (avulsion fractures of the proximal lateral tibia) are highly associated with anterior cruciate ligament (ACL) tears in adult patients. This large case series of pediatric Segond fractures describes the associated intra-articular knee injuries to determine if these fractures have a high incidence of ACL tears or its equivalent injury in young patients.

METHODS

Institutional review board approved retrospective study at a tertiary children's hospital of patients under 19 years who were diagnosed with a Segond fracture between 2009 and 2019 was conducted. Demographics, clinical data, imaging features, associated injuries, and treatment information were collected.

RESULTS

Fifty-three patients (44 males and 9 females) with median age 15.4 (11.8 to 19) years with Segond fractures of the proximal tibia on radiographic imaging were included. Diagnosis of associated injuries was established based on clinical examination, radiology report, and arthroscopic findings. Median Segond fracture size was 2.0×9.0 mm measured on standard anteroposterior knee radiographs. Magnetic resonance imaging (MRI) was obtained in 49/53 (92.5%) patients. Associated injuries included ACL tears (39 patients, 73.6%), tibial spine fractures (9, 17.0%), and other injuries (5, 9.4%). 37/53 (69.8%) patients had meniscal injury. Three (5.7%) patients sustained multiligament injuries. All associated injuries were confirmed by either MRI/computerized tomography or direct operative examination. Among Segond fractures found with ACL tears, 12 (30.8%) were contact injuries, 30 (76.9%) were sports injuries. In associated tibial spine fractures, 7 (78%) injuries were contact in nature and were sports related. There was a statistically significant difference (P=0.013) in age, patients with tibial spine fractures (median 13.6 y) being younger than those with ACL tears (median 15.4 y). 12/53 (22.6%) had associated articular cartilaginous injuries, 3 of which were treated surgically. Overall, 81.1% of patients were treated operatively for associated intra-articular injuries.

CONCLUSIONS

This large case series of Pediatric Segond fractures suggests a high association with intra-articular injuries, specifically, ACL tears and its equivalent injury, that is, tibial spine fractures, the later more common in the younger patient population. An MRI is recommended in patients with a Segond fracture for characterizing the exact intra-articular injury to help plan the appropriate management.

LEVEL OF EVIDENCE

Level IV-prognostic.

Anatomic reconstruction of the anterior cruciate ligament of the knee with or without reconstruction of the anterolateral ligament: A meta-analysis

PURPOSE

To systematically analyze the effectiveness between combined anterior cruciate ligament and anterolateral ligament reconstruction (ACL+ALLR) and isolated anterior cruciate ligament reconstruction (ACLR) for treatment of patients with injured ACL.

METHODS

We performed a systematic search in MEDLINE, EMBASE, PubMed, Web of Science, Cochrane databases, Chinese Biomedical Literature Database, CNKI, and Wanfang Data for all relevant studies. All statistical analysis was performed using Review Manager version 5.3.

RESULTS

A total of six articles with 460 study subjects were included, with 193 patients in ACL+ALL reconstruction group and 267 patients in ACL reconstruction group. The results of the meta-analysis showed that the ACL+ALL reconstruction group had significantly lower KT measured value (P < 0.00001), Lachman test positive-rate (P = 0.02), Pivot-shift test positive-rate (P < 0.00001) and graft rupture rate (P = 0.02) compared with the ACL reconstruction group. Higher IKDC score (P < 0.00001) and Lysholm score (P < 0.00001) were measured in ACL+ALL reconstruction group, while infection rate (P = 0.86) and other complications rate (P = 0.29) showed no significant differences between the two groups.

CONCLUSIONS

Anatomic reconstruction of the ACL of the knee with reconstruction of the ALL indicates better postoperative knee function and clinical outcomes compared with isolated ACL reconstruction. The infection rate and other complications rate showed no significant difference between two groups.

The Anterolateral Ligament Has Limited Intrinsic Healing Potential: A Serial, 3-Dimensional-Magnetic Resonance Imaging Study of Anterior Cruciate Ligament-Injured Knees From the SANTI Study Group

BACKGROUND

Recent imaging studies demonstrate that the anterolateral ligament (ALL) is frequently injured at the time of anterior cruciate ligament (ACL) rupture. The intrinsic healing potential of these injuries after ACL reconstruction (ACLR) has not been defined.

PURPOSE/HYPOTHESIS

The primary objective was to evaluate the rate and duration of the healing process of injured ALLs after ACLR using serial 3-dimensional magnetic resonance imaging (3D-MRI). The secondary objective was to investigate whether any patient, injury, or surgical factors influenced the healing rate. The hypothesis was that serial imaging would demonstrate that the ALL has limited healing potential.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

Patients enrolled in the study underwent 3D-MRI (slice thickness 0.5 mm) preoperatively and at 1, 6, 12, and 24 months after ACLR. Three observers determined the grade of ALL injury according to the Muramatsu classification. Inter- and intraobserver reliabilities were calculated. The rates of injury and time points for healing were determined. Full healing was defined as a change from a preoperative Muramatsu grade of B or C (indicating partial or complete injury) to grade A (normal). Multivariate analysis was used to investigate the association of aforementioned factors with the risk of incomplete healing.

RESULTS

A total of 44 patients were enrolled in the study. Of them, 71.2% had an ALL injury on preoperative imaging. Overall, full healing of ALL injuries occurred at a rate of 3.2%, 15.2%, and 30.3% at 1, 6, and 12 months, respectively. There were no changes in the Muramatsu grade in any patient beyond 12 months postoperatively. None of the complete lesions demonstrated full healing, but the proportion of patients with a grade C injury decreased from 13.6% preoperatively to 4.5% at 12 months due to an improvement to grade B in 4 of 6 patients (66%). Inter- and intraobserver reliabilities of the classification system were almost perfect at 0.81-0.94 and 0.95-1.00, respectively. None of the potential risk factors investigated were predictive of an increased risk of nonhealing.

CONCLUSION

ALL injuries occurred in the majority of ACL-injured knees. They had limited intrinsic healing potential, with only 30.3% healing by 12 months after ACLR. The process of healing took >6 months in half of the patients in whom it occurred. No new cases of full healing occurred beyond 12 months postoperatively. No significant risk factors for failure of full healing to occur were identified, but it is likely that this aspect of the study was underpowered.

Clinical Results of Combined ACL and Anterolateral Ligament Reconstruction: A Narrative Review from the SANTI Study Group

Lateral extraarticular procedures (LEAPs) in the anterior cruciate ligament (ACL)-injured knee were widely abandoned in the 1990s but have seen a recent resurgence. The aim of this review was to demonstrate that anterolateral ligament reconstruction (ALLR) is associated with evidence of significant advantages and no evidence of historical concerns. A narrative review of the literature was performed. Combined ACL + ALLR is associated with improved outcomes when compared against isolated ACL reconstruction, including a significantly lower risk of ACL graft rupture (hazard ratio [HR]: 0.327, 95% CI: 0.130-0.758), a significantly lower risk of reoperation for secondary meniscectomy following medial meniscal repair at the time of ACL reconstruction (HR: 0.443, 95% CI: 0.218-0.866), significantly increased likelihood of return to the preinjury level of sport following primary (odds ratio [OR]: 1.938, 95% CI: 1.174-3.224) and revision ACL reconstruction (57.1 vs. 25.6%, respectively; p = 0.008), and in chronic ACL injuries, less residual pivot shift (9.1 vs. 35.3%, p = 0.011), and better IKDC (92.7 ± 5.9 vs. 87.1 ± 9.0, p = 0.0013) and Lysholm (95.4 ± 5.3 vs. 90.0 ± 7.1, p < 0.0001) scores, and no evidence of historical concerns. Combined ACLR + ALLR is associated with excellent clinical outcomes with no evidence of the adverse events that led to the historical widespread abandonment of other types of LEAP. Specifically, comparative series have demonstrated significant advantages of ALLR when compared against isolated ACLR with respect to reduced rates of ACL graft rupture, secondary meniscectomy, persistent instability, and significantly improved functional outcomes and improved return to sport metrics.

The deep lateral femoral notch sign: a reliable diagnostic tool in identifying a concomitant anterior cruciate and anterolateral ligament injury

PURPOSE

The aim of the present study was to investigate the validity and reliability of the deep lateral femoral notch sign (DLFNS) in identifying a concomitant anterior cruciate ligament (ACL)/anterolateral ligament (ALL) rupture and predicting the clinical outcomes following an anatomical single-bundle ACL reconstruction. It was hypothesized that patients with a concomitant ACL/ALL rupture would have an increased DLFNS compared to patients without a concomitant ACL/ALL rupture.

METHODS

The lateral preoperative radiographs and MRI images of 100 patients with an ACL rupture and 100 control subjects were evaluated for the presence of a DLFNS and ACL/ALL rupture, respectively. The patients were evaluated clinically preoperatively and at a minimum 1 year following the ACL reconstruction. A receiver operator curve (ROC) analysis was performed to define the optimal cut-off value of the DLFNS for identifying a concomitant ACL/ALL injury. The relative risk (RR) was also calculated to determine whether the presence of the DLFNS was a risk factor for residual instability or ACL graft rupture following an ACL reconstruction.

RESULTS

The prevalence of DLFNS was 52% in the ACL-ruptured patients and 15% in the control group. At a minimum 1-year follow-up, 35% (6/17) of the patients with DLFNS > 1.8 mm complained of persistent instability, and an MRI evaluation demonstrated a graft re-rupture rate of 12% (2/17). In patients with a DLFNS < 1.8 mm, 8% (7/83) reported a residual instability, and the graft rupture rate was 2.4% (2/83). A DLFNS > 1.8 mm demonstrated a sensitivity of 89%, a specificity of 95%, a negative predictive value of 98%, and a positive predictive value of 89% in identifying a concomitant ACL/ALL rupture. Patients with a DLFNS > 1.8 mm had 4.2 times increased risk for residual instability and graft rupture compared to patients with a DLFNS ≤ 1.8 mm.

CONCLUSIONS

A DLFNS > 1.8 mm could be a clinically relevant diagnostic tool for identifying a concomitant ACL/ALL rupture with high sensitivity and PPV. Patients with a DLFNS > 1.8 mm should be carefully evaluated for clinical and radiological signs of a concomitant ACL/ALL rupture and treated when needed with a combined intra-articular ACL reconstruction and extra-articular tenodesis to avoid a residual rotational instability and ACL graft rupture.

LEVEL OF EVIDENCE

III.

Adolescents show a lower healing rate of anterolateral ligament injury and a higher rotational laxity than adults after anterior cruciate ligament reconstruction

BACKGROUND

This study aimed to compare anterolateral ligament (ALL) injuries in anterior cruciate ligament (ACL) ruptures, as well as ALL healing and clinical outcomes following ACL reconstruction between adolescents and adults.

METHODS

This retrospective study involved 98 patients who underwent ACL reconstruction. They were divided into two groups according to age: group A (adolescents, 16-20 years of age; n = 49) and group B (adults, 21-45 years of age; n = 49). Subjective scores including ACL-Return to Sport after Injury (ACL-RSI) scale and objective tests were assessed. Follow up magnetic resonance imaging (MRI) and second-look arthroscopy was conducted at 1-year and 2-year follow up, respectively.

RESULTS

Good healing rate of ALL was higher in adults than in adolescents (P = 0.048). Graft tension and synovial coverage showed no significant differences between two groups. Group A showed a higher rate of high-grade pivot shift and a lower ACL-RSI at last follow up than group B (P = 0.126 and P = 0.016). Poor healing of ALL was significantly associated with lower ACL-RSI and failure to return to sports (P < 0.001 and P = 0.001). Re-rupture of the ACL graft was found in four (8.2%) and one (2.0%) of group A and B, respectively.

CONCLUSIONS

Adolescents showed a lower healing rate of ALL, a lower ACL-RSI, a higher rate of high-grade pivot shift than adults. Moreover, poor healing of ALL was significantly associated with a lower ACL-RSI and failure to return to sports. We suggest that adolescents need to pay more attention to the presence of ALL injury.

A Quantifiable Risk Factor for ACL Injury: Applied Mathematics to Model the Posterolateral Tibial Plateau Surface Geometry

Background:

The mechanism for traumatic ruptures of the native anterior cruciate ligament (ACL) is frequently a noncontact injury involving a valgus moment with internal rotation of the tibia. The abnormal rotation and translation of the lateral femoral condyle posteroinferiorly relative to the lateral tibial plateau is thought to be related to the geometry of the tibial plateau.

Purpose/Hypothesis:

The purpose of the study was to mathematically model the posterior tibial plateau geometry in patients with ACL injuries and compare it with that of matched controls. The hypothesis was that increased convexity and steepness of the posterior aspect of the lateral plateau would subject knees to higher forces, leading to a potentially higher risk of ACL injury.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

We mathematically modeled the posterior curvature of the lateral tibial plateau in 64 patients with ACL injuries and 68 matched controls. Using sagittal magnetic resonance imaging scans of the knee, points on the articular cartilage of the posterolateral tibial plateau were selected and curve-fitted to a power function (y = a × xⁿ). For coefficient a and coefficient n, both variables modulated the shape of the curve, where a larger magnitude represented an increase in slope steepness. Groups were compared using a Mann-Whitney test and α < .05.

Results:

There was a significant difference in surface geometry between the patients with ACL injuries and matched controls. The equation coefficients were significantly larger in the patients with ACL injuries: coefficient a (ACL injury, 0.9 vs control, 0.68; P < .0001) and coefficient n (ACL injury, 0.34 vs control, 0.30; P = .07). For coefficient a, there was a 78.9% sensitivity, 77.5% specificity, and odds ratio of 12.6 (95% CI, 5.5-29.0) for ACL injury using a cutoff coefficient a = .78.

Conclusion:

Patients with ACL injuries had a significantly greater posterolateral plateau slope. The steeper drop off may play a role in higher anterior translation forces, coupled with internal rotation torques on the knee in noncontact injury, which could increase ACL strain and predispose to ACL injury.

Isokinetic Strength After ACL Reconstruction: Influence of Concomitant Anterolateral Ligament Reconstruction

BACKGROUND

To reduce the rate of anterior cruciate ligament (ACL) graft rupture, recent surgeries have involved anterolateral ligament reconstruction (ALLR). This reconstruction procedure harvests more knee flexor muscle tendons than isolated ACL reconstruction (ACLR), but its influence on knee muscle strength recovery remains unknown. This study aimed to assess the influence of ALLR with a gracilis graft on the strength of the knee extensor and flexor muscles at 6 months postoperatively.

HYPOTHESIS

The additional amount of knee flexor harvest for ALLR would result in impairment in knee flexor muscle strength at 6 months postoperatively.

STUDY DESIGN

Retrospective cohort study.

LEVEL OF EVIDENCE

Level 2.

METHODS

A total of 186 patients were assigned to 2 groups according to the type of surgery: ACL + ALLR (graft: semitendinosus + gracilis, n = 119) or isolated ACLR (graft: semitendinosus, n = 67). The strength of the knee extensor and flexor muscles was assessed using an isokinetic dynamometer at 90, 180, and 240 deg/s for concentric and 30 deg/s for eccentric contractions and compared between groups using analysis of variance statistical parametric mapping.

RESULTS

Regardless of the surgery and the muscle, the injured leg produced significantly less strength than the uninjured leg throughout knee flexion and extension from 30° to 90° for each angular velocity (30, 90, 180, and 240 deg/s). However, the knee muscle strength was similar between the ACL + ALLR and ACLR groups.

CONCLUSION

The addition of ALLR using the gracilis tendon during ACLR does not alter the muscle recovery observed at 6 months postoperatively.

CLINICAL RELEVANCE

Although more knee flexor muscle tendons were harvested in ACL + ALLR, the postoperative strength recovery was similar to that of isolated ACLR.

Femoral and tibial bone bruise volume is not correlated with ALL injury or rotational instability in patients with ACL-deficient knee

PURPOSE

Some researchers have suggested that bone bruises are evidence of rotational instability. The hypothesis was that the extent of lateral bone edema is correlated with the presence of an anterolateral ligament (ALL) injury. The main objective was to determine whether there was a correlation between the presence of an ALL injury the extent of bone bruises.

METHODS

A prospective diagnostic study enrolled all the patients who suffered an acute anterior cruciate ligament (ACL) who were operated on within 8 weeks. The extent of bone bruising according to the ICRS classification was measured on preoperative MRIs by two independent blinded raters twice with an interval of 4 weeks. Dynamic ultrasonography (US) to look for ALL injury and the pivot shift test were performed before the ACL surgery. The correlation between ALL injury and bone bruises, and the correlation between an ALL injury and a high-grade pivot shift test were determined.

RESULTS

Sixty-one patients were included; 52% of patients had an ALL injury on US. The extent of lateral bone bruise was not related to the presence of an ALL injury, nor related to the presence of a high-grade pivot shift. A grade 2 or 3 pivot shift was significantly correlated with an ALL injury (p < 0.0001). Inter- and intra-rater reliability for the bone bruise rating was excellent.

CONCLUSION

The extent of lateral bone bruise is not correlated with ALL injury or a high-grade pivot shift; thus, it is not correlated with rotational instability of the knee.

LEVEL OF EVIDENCE

II.

Effects of Anterolateral Structure Augmentation on the In Vivo Kinematics of Anterior Cruciate Ligament-Reconstructed Knees

BACKGROUND

Double-bundle anterior cruciate ligament (ACL) reconstruction (ACLR) is a well-known treatment that restores the stability of ACL-deficient knees. However, some isolated ACL-reconstructed knees ultimately show rotatory laxity and develop osteoarthritis. Whether combined ACLR with anterolateral structure (ALS) augmentation (ALSA) can provide better improvement in the in vivo knee rotational kinematics remains unknown.

HYPOTHESIS

When compared with isolated double-bundle ACLR, combined double-bundle ACLR with ALSA can improve knee in vivo rotational kinematics and provide better restoration of knee kinematics.

STUDY DESIGN

Controlled laboratory study.

METHODS

Sixteen patients with unilateral ACL injury were randomly divided into 2 groups to receive either combined double-bundle ACLR and ALSA (ALSA group) or isolated double-bundle ACLR (ACLR group). All patients performed a single-leg lunge using the operative and nonoperative/contralateral legs under dual-fluoroscopic imaging system surveillance during a hospital visit at a minimum 1 year (12-13 months) of follow-up to assess the 6 degrees of freedom knee kinematics. Functional evaluation using the Lysholm and Marx rating scales and clinical examinations were also performed.

RESULTS

From full extension to approximately 90° of knee flexion at 5° intervals, the mean ± SD internal rotation of the reconstructed knees in the ALSA group (1.5°± 0.9°) was significantly smaller than that of the contralateral knees (8.2°± 1.9°; P = .008). The ALSA group knees also showed significantly (P = .045) more medial translation than the contralateral knees. In the ACLR group, the mean internal rotation of the reconstructed knee (6.0°± 2.1°) was significantly smaller than that of the contralateral knees (8.9°± 0.6°; P < .001). At full extension, the tibia was significantly more externally rotated than that of the contralateral legs (0.5°± 7.4° vs 7.6°± 3.4°, P = .049).

CONCLUSION

When compared with isolated double-bundle ACLR, double-bundle ACLR augmented with ALS reconstruction resulted in anterolateral rotatory overconstraint during the lunge motion.

CLINICAL RELEVANCE

Additional ALSA of double-bundle ACL-reconstructed knees overconstrained rotatory stability. Therefore, the use of ALSA for ACL-reconstructed knees should be considered with caution for patients with ACL deficiency and anterolateral rotatory instability. Longer-term follow-up to evaluate long-term outcomes and altered kinematics over time is recommended.

Does the anterolateral ligament protect the anterior cruciate ligament in the most common injury mechanisms? A human knee model study

BACKGROUND

Anterior cruciate ligament (ACL) reconstruction still has a risk of re-rupture and persisting rotational instability. Thus, extra-articular structures such as the anterolateral ligament (ALL) are increasingly treated. The ALL however prevents the internal rotation of the tibia and it must be doubted that the ALL protects the ACL in other common injury mechanisms which primarily include tibial external rotation. In this study we aimed to evaluate which extra-articular structures support the ACL in excessive tibial internal and external rotation using a knee finite element (FE) model.

METHODS

Internal and external rotations of the tibia were applied to an FE model with anatomical ACL, posterior cruciate ligament (PCL), lateral collateral ligament (LCL), medial collateral ligament (MCL) and intact medial and lateral meniscus. Three additional anatomic structures (anterolateral ligament, popliteal tendon and posterior oblique ligament) were added to the FE model separately and then all together. The force histories within all structures were measured and determined for each case.

RESULTS

The ACL was the most loaded ligament both in tibial internal and external rotation. The ALL was the main stabilizer of the tibial internal rotation (46%) and prevented the tibial external rotation by only 3%. High forces were only observed in the LCL with tibial external rotation. The ALL reduced the load on the ACL in tibial internal rotation by 21%, in tibial external rotation only by 2%. The POL reduced the load on the ACL by 8%, the PLT by 6% in tibial internal rotation. In tibial external rotation the POL and PLT did not reduce the load on the ACL by more than 1%.

CONCLUSION

The ALL protects the ACL in injury mechanisms with tibial internal rotation but not in mechanisms with tibial external rotation. In injury mechanisms with tibial external rotation other structures that support the ACL need to be considered.

The Lateral Femoral Notch Sign Is Correlated With Increased Rotatory Laxity After Anterior Cruciate Ligament Injury: Pivot Shift Quantification With A Surgical Navigation System

BACKGROUND

The lateral femoral notch sign (LNS) is a bony impression on the lateral femoral condyle correlated with anterior cruciate ligament (ACL) injury. Its presence is associated with lateral meniscal injury and higher cartilage degradation on the lateral femoral condyle.

PURPOSE/HYPOTHESIS

The purpose was to investigate the effect of the presence and magnitude of LNS on rotatory instability. The hypothesis was that a positive LNS is correlated with a high-grade pivot shift (PS).

STUDY DESIGN

Cross-sectional study; Level of evidence, 3.

METHODS

A total of 90 consecutive patients with complete ACL tears between 2013 and 2017 underwent intraoperative kinematic evaluation with the surgical navigation system and were included in the present study. The same surgeon performed a standardized PS under anesthesia. The PS was quantified through the acceleration of the lateral compartment during tibial reduction (PS ACC) and the internal-external rotation (PS IE). Presence and depth of LNS were evaluated on sagittal magnetic resonance images (1.5-T).

RESULTS

In 47 patients, the LNS was absent; in 33, the LNS depth was between 1 mm and 2 mm; and in 10 patients, it was deeper than 2 mm. Patients with a notch deeper than 2 mm showed increased PS ACC and PS IE compared with the group without the LNS. However, no significant differences were present between the group with a notch between 1 and 2 mm and the patients without LNS. Receiver operating characteristic curve analysis showed that 2 mm was the most predictive cutoff value to identify the "high-grade rotatory instability" group, with an accuracy of 77.8% and 74.4% and a specificity of 95.5% and 93.9% referred to the PS ACC and PS IE, respectively.

CONCLUSION

The presence of a lateral LNS deeper than 2 mm could be used for the preoperative identification of patients with a high risk of increased rotatory instability.

The anatomy of Kaplan fibers

PURPOSE

Kaplan fibers (KF) have been described as connections between the iliotibial band and the distal femur. They are divided into two distinct structures, proximal (PKF) and distal (DKF) fibers, which may participate in the control of the rotatory knee stability. Their anatomical characteristics have not been investigated completely, in particular with respect to reconstruction procedures. The aim was to determine their anatomical characteristics and their morphological variation.

METHODS

Twenty-one nonpaired fresh frozen human cadaveric knees (from whole leg) were used for the analysis of PKF and DKF through an anterolateral approach. The anatomical relationships between the adjacent anterolateral structures were reported and anatomical characteristics of PKF and DKF (thickness, width and length) measured at 50° knee flexion under different rotational conditions (neutral: NR, Internal at 5Nm: IR applied with a dynamometric torque rig). Bony ridges of PKF and DKF were measured.

RESULTS

PKF and DKF and their respective bony ridges were individually identified in all knees studied (n = 21). The PKF and DKF were proximal and posterior to the lateral femoral epicondyle, respective distances 49.20 ± 7.38 and 27.54 ± 7.69 mm. DKF were thicker (p < 0.001), wider (p < 0.001) and longer (p < 0.001) than the PKF, regardless of the tibial rotation applied. Tensioning of KF was achieved in IR with a decrease in thickness and width, alongside fiber lengthening (p < 0.001).

CONCLUSION

PKF and DKF are distinct and constant anatomical structures of the lateral compartment of the knee, whose anatomical characteristics and their tensioning in IR presume a function of controlling rotational knee stability.

Correlation Between the Thickness of Anterolateral Ligament and Lateral Collateral Ligament of the Knee

Background

Persistent anterolateral rotatory instability (ALRI) following the anterior cruciate ligament (ACL) reconstruction has led to a renewed interest in defining the role of anterolateral complex (ALC) of the knee.

Methods

We explored the anterolateral corner of 34 cadaveric knees to define the anterolateral ligament (ALL) in all its dimensions and measured the thickness of lateral collateral ligament (LCL) at the lateral meniscus level (tLCL) in ALL-intact and ALL-deficient knees.

Results

ALL was present in 27/34 (79%) of the knees. We found complete ALL in 13 cadavers bilaterally. ALL was absent bilaterally in three cadavers; it was present on one side and absent contralaterally in one cadaver. In ALL-intact knees, the average tLCL was 2.05 mm, whereas, in ALL-deficient knees, it was 2.57 mm. This difference in tLCL was statistically significant.

Conclusions

Our study adds new data to the recent voluminous research on ALL. We have examined the correlation between the thickness of ALL and LCL and documented alterations in the thickness of LCL in ALL-intact knees. These findings would help in designing reconstructive procedures for the combined ACL injury with ALRI.

Anterior cruciate ligament reconstruction: the role of lateral posterior tibial slope as a potential risk factor for failure

Background and aim of the work:

Anterior cruciate ligament (ACL) reconstructions is an extremely frequent surgery. The analysis of anatomical factors is becoming increasingly important and the study of clinical, arthroscopic and radiological methods to evaluate and understand them aims to positively affect the patient’s outcome. This work aims to analytically analyze the anatomical factors that can influence the failure of an ACL reconstruction, to evaluate the data collected on a sample of patients undergoing ACL revision and compare them with those is present in the literature.

Materials and Methods:

At the Clinic of Orthopedic of Udine, between November 2018 and August 2020 were performed 47 revisions of the ACL. We analyzed MRI scans about Lateral Posterior Tibial Slope (LPTS). Patient surveys were analyzed by a single senior orthopedic surgeon who was blinded to patient history, age and gender.

Results:

Comparing with a value considered in the norm (LPTS estimated 6.5°) we see how the difference between the average LPTS values in the sample is significantly higher than the normal values (P <.0001). Dividing the simple according to sex, we notice that the LPTS in female patients is 11.8 while in male patients it is 8.7° (P <.005).

Conclusion:

The data collected show how an increased posterior lateral tibial slope can be correlated with a higher risk of ACL failure. The results are in line with what is present in the literature. Our analysis is absolutely preliminary, but it is intended to be the starting point of a path that allows us to think of the reconstruction of the ACL as an intervention to be planned more carefully based on the individual characteristics of the patient. (www.actabiomedica.it)

Minimally Invasive Modified Lemaire Tenodesis

Increasing emphasis in the literature is recently being put on controlling rotational stability in patients with an anterior cruciate ligament rupture by addressing the anterolateral complex during anterior cruciate ligament reconstruction. Many different techniques for lateral extra-articular tenodesis have been described, with the (modified) Lemaire technique being widely favored. Recent literature does report that lateral extra-articular tenodesis leads to a reduction in persistent rotatory laxity and graft rupture rate, but also may be associated with increased pain, reduced quadriceps strength, reduced subjective functional recovery, and cosmetic complaints. Thus this article aims to describe our minimally invasive technique for a modified Lemaire tenodesis.

Continuous moderate intensity versus discontinuous high intensity treadmill running on anterior cruciate ligament laxity and hamstrings flexibility in eumenorrheic women

OBJECTIVE

To differentiate running intensity and menstrual phase effects on knee stability before and after exercise.

METHODS

Ten eumenorrheic aerobically trained females were recruited to determine effects of a randomized crossover design of exercise intensity (85%HRR vs 42.5%HRR) on anterior cruciate ligament laxity (APLAX) and hamstrings flexibility (HF). A KT-2000 arthrometer measured APLAX and a 90-90 supine knee extension (MKE) and sit-and-reach test (SRD) measured HF in follicular (FP) and luteal (LP) menstrual cycle phases.

RESULTS

Significant difference pre-exercise was observed for both 90N and 120N APLAX in LP compared to FP. Exercise increased APLAX at 90N and 120N in both FP and LP with LP exhibiting larger changes than FP. MKE and SRD increased significantly following exercise but were not different across menstrual phases or between exercise intensities.

CONCLUSION

APLAX taken together with increased HF post-exercise demonstrates a less stable knee joint in the LP before and following exercise.

Different anterolateral procedures have variable impact on knee kinematics and stability when performed in combination with anterior cruciate ligament reconstruction

OBJECTIVE

The optimal anterolateral procedure to control anterolateral rotational laxity of the knee is still unknown. The objective was to compare the ability of five anterolateral procedures performed in combination with anterior cruciate ligament reconstruction (ACLR) to restore native knee kinematics in the setting of a deficient anterior cruciate ligament (ACL) and anterolateral structures.

METHODS

A controlled laboratory study was performed using 10 fresh-frozen cadaveric whole lower limbs with intact iliotibial band. Kinematics from 0° to 90° of flexion were recorded using a motion analysis three-dimensional (3D) optoelectronic system, allowing assessment of internal rotation (IR) and anteroposterior (AP) tibial translation at 30° and 90° of flexion. Joint centres and bony landmarks were calculated from 3D bone models obtained from CT scans. Intact knee kinematics were assessed initially, followed by sequential section of the ACL and anterolateral structures (anterolateral ligament, anterolateral capsule and Kaplan fibres). After ACLR, five anterolateral procedures were performed consecutively on the same knee: ALLR, modified Ellison, deep Lemaire, superficial Lemaire and modified MacIntosh. The last three procedures were randomised. For each procedure, the graft was fixed in neutral rotation at 30° of flexion and with a tension of 20 N.

RESULTS

Isolated ACLR did not restore normal overall knee kinematics in a combined ACL plus anterolateral-deficient knee, leaving a residual tibial rotational laxity (p=0.034). Only the ALLR (p=0.661) and modified Ellison procedure (p=0.641) restored overall IR kinematics to the normal intact state. Superficial and deep Lemaire and modified MacIntosh tenodeses overconstrained IR, leading to shifted and different kinematics compared with the intact condition (p=0.004, p=0.001 and p=0.045, respectively). Compared with ACLR state, addition of an anterolateral procedure did not induce any additional control on AP translation at 30° and 90° of flexion (all p>0.05), except for the superficial Lemaire procedure at 90° (p=0.032).

CONCLUSION

In biomechanical in vitro setting, a comparison of five anterolateral procedures revealed that addition of either ALLR or modified Ellison procedure restored overall native knee kinematics in a combined ACL plus anterolateral-deficient knee. Superficial and deep Lemaire and modified MacIntosh tenodeses achieved excellent rotational control but overconstrained IR, leading to a change from intact knee kinematics.

LEVEL OF EVIDENCE

The level-of-evidence statement does not apply for this laboratory experiments study.

Outcomes After Isolated Acute Anterior Cruciate Ligament Reconstruction Are Inferior in Patients With an Associated Anterolateral Ligament Injury

BACKGROUND

Isolated reconstruction of the anterior cruciate ligament (ACL) does not reestablish the normal knee biomechanics in cases of associated injuries to the anterolateral structures. Studies evaluating the potential clinical effect of anterolateral ligament (ALL) injury on the treatment of ACL injuries are necessary to validate the findings of biomechanical studies.

PURPOSE

To evaluate the clinical outcomes and failure rate of ACL reconstruction in patients with and without ALL injury diagnosed using magnetic resonance imaging.

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 group) or absence (no-ALL group) of ALL injury on preoperative magnetic resonance imaging scans. Both groups underwent anatomic reconstruction of the ACL with autologous hamstring tendon grafts. The Lysholm and subjective IKDC scores (International Knee Documentation Committee), KT-1000 arthrometer and pivot-shift test results, reconstruction failure rate, incidence of contralateral ACL injury, presence of associated meniscal injury, and presence of knee hyperextension were evaluated.

RESULTS

A total of 182 patients were evaluated. Postoperative mean ± SD follow-up was 33.6 ± 7.1 and 36.1 ± 8.1 months for the ALL and no-ALL groups, respectively. No significant differences were found between the groups in terms of age, sex, knee hyperextension, duration of injury before reconstruction, follow-up time, or associated meniscal injuries. In the preoperative evaluation, the pivot-shift grade was similar, and the ALL group had worse KT-1000 arthrometer values (7.9 ± 1.2 mm vs 7.2 ± 1.1 mm; P < .001). In the postoperative evaluation, patients in the no-ALL group had a lower reconstruction failure rate (10.2% vs 1.4%; P = .029) and better clinical outcomes according to the IKDC subjective (85.5 ± 10.7 vs 89.1 ± 6.6; P = .035) and Lysholm scores (85.9 ± 10.1 vs 92.0 ± 6.3; P < .001). There was no postoperative difference in the KT-1000 or pivot-shift results.

CONCLUSION

Combined ACL and ALL injuries were associated with significantly less favorable outcomes than were isolated ACL injuries at a minimum follow-up of 2 years after ACL reconstruction. Patients with concomitant ALL injury showed a higher rerupture rate and worse functional scores.

All-inside technique in ACL reconstruction: mid-term clinical outcomes and comparison with AM technique (Hamstrings and BpTB grafts)

Purpose

The aim of this study was to define the subjective and objective clinical results of all-inside surgical technique at a medium-term follow-up and to compare these results with those obtained from antero-medial (AM) ACL reconstruction technique using hamstrings (HS) or bone-patellar tendon-bone (BpTB) grafts to detect eventual superiority of one technique to another.

Methods

A retrospective analysis of routinely collected data was conducted. Inclusion criteria were ACL reconstruction through all-inside technique or AM technique with HS or BpTB performed between January 2015 and May 2018; age between 15 and 30 year old; minimum 24 months’ available follow-up. Exclusion criteria were contralateral ACL reconstruction; need for any other associated procedures during surgery. Clinical outcomes were assessed with KOOS, Lysholm, Tegner scores and KT-1000 device.

Results

According to the selection criteria, 157 patients were enrolled and divided subsequently into 3 groups: all-inside (51 patients), AM-HS (53 patients) and AM-BpTB (53 patients). A significant postoperative improvement of each score in all groups was detected. The mean KT-1000 was 3.1 ± 1.0 mm in all-inside group, while 3.3 ± 1.4 mm and 2.5 ± 0.4 mm in AM-HS and AM-BpTB groups, respectively. Comparing the results obtained, no statistically significant difference was found between the three techniques (p = 0.27). Statistically significant differences were highlighted in surgical duration: all-inside method was the longest (117′), followed by AM-BpTB surgery (101′) and AM-HS technique (87′).

Conclusions

The all-inside technique showed good postoperative results at medium-term follow-up. It could be a valuable solution for ACL reconstruction, especially in young patients due to its less invasiveness, despite surgical skills and time needed.

Levels of evidence

Level IV.

Reconstruction of the anterior cruciate- and anterolateral ligament deficient knee with a modified iliotibial graft reduces instability more than with an intra-articular hamstring graft

PURPOSE

To compare knee kinematics before and after anterior cruciate ligament ACL reconstruction (ACL-R) using hamstring graft (HG) and a double-stranded iliotibial tract graft attached to Gerdy's tubercle (providing an extra-articular anterolateral tenodesis) (named the modified iliotibial tract graft = MIT).

METHOD

Eighteen cadaveric knees were tested in a 6 degree of freedom kinematics rig. An optical tracking system recorded kinematics of the knee from 0 to 80 degrees of flexion applying no load, internal/external rotation (IR/ER), valgus/varus rotation (VGR/VRR), simulated pivot shift (SPS), anterior translation (AT) and posterior translation loads. The knee was tested before and after resection of the ACL and the anterolateral ligament (ALL), respectively; then after HG-ACL-R and MIT-ACL-R. Grafts were fixed at 20° of flexion. Results were compared to the intact knee.

RESULTS

ACL resection resulted in a significant increase in AT (p < 0.05) over the entire range of motion, peaking at 20° of flexion, mean difference 6.6 ± 2.25 mm (p = 0.0007). ACL-R with HG-ACL and MIT-ACL restored AT. Resection of the ALL increased IR in the fully extended knee, mean difference 2.4 ± 2.1° (p = 0.024). When compared to the intact knee and the knee after HG-ACL-R, MIT-ACL-R knee reduced IR/SPS significantly (p < 0.05) in deep flexion angles (60°-80°), peaking at 80° of flexion. The MIT-ACL-R caused significantly less VRR at 80° flexion (p = 0.02).

CONCLUSION

MIT-ACL-R restored AT equally to the HG-ACL-R. The MIT-ACL-R reduced IR and SPS in deep flexion, resulting in overconstraint. MIT-ACL-R can be used as an alternative to standard reconstruction methods.

Plantaris tendon: a novel graft for anterolateral ligament reconstruction and additional reinforcement for anterior cruciate ligament autografts in combined reconstructive procedures

The anterolateral ligament is recently recognized as an important structure in restoring rotational stability of the anterior cruciate ligament-deficient knee. Biomechanical and clinical studies confirmed the benefits of concurrent anterior cruciate ligament and anterolateral ligament reconstruction. However, present techniques mostly use hamstring tendons autografts and therefore additionally disrupt the knee biomechanics. The plantaris tendon is a well known and accessible graft and has excellent biomechanical properties for anterolateral ligament reconstruction. The present paper describes a new combined anterior cruciate ligament and anterolateral ligament reconstruction technique using plantaris tendon and semitendinosus tendon.Level of evidence V (Case report).