Younger age, longer delay to surgery and meniscal tears are associated with a smaller ACL remnant: An analysis from the registry of the Francophone Arthroscopic Society.

PURPOSE: This study aimed to evaluate which preoperative patient, injury or clinical factors were associated with the anterior cruciate ligament (ACL) remnant volume in patients undergoing ACL surgery. It was hypothesized that the main factors determining an insufficient ACL remnant volume at the time of surgery were younger age and longer time to surgery. METHODS: A retrospective analysis from the Francophone Arthroscopic Society's registry was conducted, including 1565 patients with an ACL lesion underdoing a primary ACL surgery (reconstruction or repair) between June 2020 and June 2023. Patients were excluded in case of revision surgery and incomplete data. Preoperative factors-including patient demographics, delay to surgery, preoperative laxity and the presence of meniscal tears or cartilage lesions-were analysed to determine their influence on ACL remnant volume (estimated by the surgeon as the percentage of residual volume). Univariate, multivariate and receiver operating characteristic curve analyses were performed to explore these relationships. RESULTS: Multivariate analyses demonstrated that younger age (<20 years and 20-30 years compared to ≥40, p = 0.02), higher time from injury to surgery (≥12 months compared to <3 months, p = 0.01) and the presence of a medial (p = 0.01) or a lateral meniscal tear (p = 0.02) were significant predictors of an ACL remnant volume ≤ 50%. CONCLUSIONS: Younger age (under 30 years of age), a time from injury to surgery above 12 months and the presence of medial and lateral meniscal tears are associated with higher odds of observing a smaller ACL remnant volume at the time of the ACL surgery. These factors should be considered when planning ACL remnant preservation techniques. LEVEL OF EVIDENCE: Level III.

A new patient-reported outcome measure for the evaluation of ankle instability: description of the development process and validation protocol.

BACKGROUND: Acute ankle sprains represent one of the most common traumatic injuries to the musculoskeletal system. Many individuals with these injuries experience unresolved symptoms such as instability and recurrent sprains, leading to chronic ankle instability (CAI), which affects their ability to maintain an active lifestyle. While rehabilitation programs focusing on sensorimotor, neuromuscular, strength and balance training are primary treatments, some patients require surgery when rehabilitation fails. A critical analysis of the patient-reported outcome tools (PROs) used to assess CAI surgical outcomes raises some concerns about their measurement properties in CAI patients, which may ultimately affect the quality of evidence supporting current surgical practice. The aim of this research is to develop and validate a new PRO for the assessment of ankle instability and CAI treatment outcomes, following recent methodological guidelines, with the implicit aim of contributing to the generation of scientifically meaningful evidence for clinical practice in patients with ankle instability. METHODS: Following the COnsensus-based Standards for the selection of Health Measurement Instruments (COSMIN), an Ankle Instability Treatment Index (AITI) will be developed and validated. The process begins with qualitative research based on face‒to‒face interviews with CAI individuals to explore the subjective experience of living with ankle instability. The data from the interviews will be coded following an inductive approach and used to develop the AITI content. The preliminary version of the scale will be refined through an additional round of face‒to‒face interviews with a new set of CAI subjects to define the AITI content coverage, relevance and clarity. Once content validity has been examined, the AITI will be subjected to quantitative analysis of different measurement properties: construct validity, reliability and responsiveness. DISCUSSION: The development of AITI aims to address the limitations of existing instruments for evaluating surgical outcomes in patients with CAI. By incorporating patient input and adhering to contemporary standards for validity and reliability, this tool seeks to provide a reliable and meaningful assessment of treatment effects. TRIAL REGISTRATION: Not applicable.

Nonanatomic Posteromedial Bundle Augmentation of the Posterior Cruciate Ligament after Hyperextension Trauma.

The surgical management of posterior cruciate ligament (PCL) injuries can be challenging. As most PCL injuries occur in a flexed knee position, the anterolateral bundle is thought to be more commonly injured than the posteromedial bundle (PMB); however, in hyperextension, the PMB plays a more significant role. The smaller size of the PMB compared with the anterolateral bundle and its lower strength may explain why isolated hyperextension PMB injuries can be easily overlooked. In this Technical Note, a surgical technique to perform a nonanatomic PMB augmentation of the PCL using a gracilis tendon autograft or allograft is reported. These technical features aim to overcome current limitations in existing techniques to address the symptoms after partial PCL hyperextension injuries.

Injuries of the posteromedial bundle of the posterior cruciate ligament after knee hyperextension trauma: A new clinical entity based on an original case series.

Purpose: This original case series aims to describe an uncommon triad of clinical signs in patients presenting with persistent pain and inability to resume physical activities after knee hyperextension trauma. Methods: Patient history, clinical examination, arthroscopic findings and investigations of 12 patients who consulted with the senior author are presented. Results: Twelve patients (seven males/five females) presented with persistent pain after knee hyperextension trauma either in sport or a traffic accident. They had a median age of 18.5 and a median body mass index of 23 kg/m2. All had medical visits and at least one magnetic resonance imaging (MRI) before visiting the senior author's institution but the cause of their problems could not be explained. The clinical examination of the injured knee appeared normal except for an uncommon triad of clinical signs with the knee close to extension: (1) a grade 1+ anterior-posterior laxity around 10-20° of knee flexion with a firm end-point (pseudo-Lachman sign), (2) a grade 1+ tibiofemoral step-off sign with a posterior drawer at 10-20° of knee flexion and (3) an increased knee hyperextension compared to the contralateral side. Arthroscopy of eight patients confirmed the pseudo-Lachman sign with a grade I posterior drawer close to knee extension, normal posterior laxity at 90° of knee flexion and an intact anterior cruciate ligament. Conclusion: Patients displayed an increased hyperextension and posterior laxity close to knee extension which normalised at 90° of knee flexion. In patients with a history of knee hyperextension trauma associated with persistent pain, inability to resume physical activities, inconclusive MRIs and a standard clinical examination, clinicians should consider extending their investigations with the knee close to extension to identify this clinical triad consistent with a lesion to the posteromedial bundle of the posterior cruciate ligament. Level of evidence: Level IV.

Blood and urine biomarkers for the diagnosis of early stages of knee osteoarthritis: A systematic review.

Purpose: To identify biomarkers in human blood or urine at an early stage of knee osteoarthritis (OA) and to elucidate if any can accurately differentiate between healthy controls and early knee OA patients and be considered as a candidate for widespread clinical use for early diagnosis of the disease. Methods: Medline, Embase and Web of Science were screened to identify comparative studies measuring differences in blood or urine biomarkers between healthy controls and knee OA patients at an early stage (grade 1 or 2 Kellgren-Laurence). Two independent reviewers screened the abstracts for eligibility, reviewed the full texts, assessed the methodological quality and extracted the data. The Joanna Briggs Institute critical appraisal tool for diagnostic test accuracy studies was used to assess the quality of the included studies. Due to relevant heterogeneity, meta-analysis was not appropriate. Results: Five studies met the eligibility criteria. The examined biomarkers were adropin, collagen type II metabolite, C-terminal cross-linked telopeptide of type II collagen, C-terminal cross-linked telopeptide of type I collagen, cartilage oligomeric matrix protein, matrix metalloproteinase 3, N-terminal propeptide of procollagen type IIA, type I procollagen N-terminal propeptides, N-terminal osteocalcin, angiopoietin-2, follistatin, granulocyte colony-stimulating factor, hepatocyte growth factor, interleukin-8, leptin, platelet-derived growth factor-BB, platelet endothelial cell adhesion molecule-1, vascular endothelial growth factor and calprotectin and totalling 19 biomarkers. All of the biomarkers were studied only once in the selected papers. Conclusions: There is no reliable biomarker available to differentiate between early knee OA in patients and healthy controls, but a potential role of a cluster of biomarkers to close this gap. There are several limitations, including inappropriate study designs, small sample sizes, nonconsecutive patient groups and inadequate statistical methods for evaluating biomarker performance in studies included. Level of Evidence: Level III.

Horizontal Cleavage Meniscus Tear: "The Quad Tendon Augmentation Technique".

The management of medial meniscus horizontal cleavage tears can be challenging. Currently, several treatment options, including nonoperative and surgical options, have been proposed in the literature. Different repair techniques aiming to promote the healing process have been reported and have shown good outcomes. However, recurrent parameniscal cysts and decreased meniscal volume have also been reported. In this Technical Note, a novel surgical technique to repair a horizontal cleavage tear of the posterior horn of the medial meniscus is reported in young patients. The technique uses a strip of autologous quadriceps tendon to fill the void between the upper and lower meniscal leaflets followed by an all-inside compression suture. Both of these technical features aim to overcome the limitations of current repair techniques.

Restoring the Preoperative Phenotype According to the Coronal Plane Alignment of the Knee Classification After Total Knee Arthroplasty Leads to Better Functional Results.

BACKGROUND: Mechanical alignment after total knee arthroplasty (TKA) is still widely used in the surgical community, but the alignment finally obtained by conventional techniques remains uncertain. The recent Coronal Plane Alignment of the Knee (CPAK) classification distinguishes 9 knee phenotypes according to constitutional alignment and joint line obliquity (JLO). The aim of this study was to assess the phenotypes of osteoarthritic patients before and after TKA using mechanical alignment and to analyze the influence of CPAK restoration on functional outcomes. METHODS: This retrospective multicenter study included 178 TKAs with a minimum follow-up of 2 years. Patients were operated on using a conventional technique with the goal of neutral mechanical alignment. The CPAK grade (1 to 9), considering the arithmetic Hip-Knee-Ankle angle (aHKA) and the JLO, was determined before and after TKA. Functional results were assessed using the following patient-reported outcome measures: Knee Injury and Osteoarthritis Outcome Score, the Simple Knee Value, and the Forgotten Joint Score. RESULTS: A true neutral mechanical alignment was obtained in only 37.1%. Isolated restoration of JLO was found in 31.4%, and isolated restoration of the aHKA in 44.9%. Exact restoration of the CPAK phenotype was found in 14.6%. Restoration of the CPAK grade was associated with an improvement in the "daily living": 79.2 ± 5.3 versus 62.5 ± 2.3 (R2 = 0.05, P < .05) and "Quality of life" Knee Injury and Osteoarthritis Outcome Score subscales: 73.8 ± 5.0 versus 62.9 ± 2.2 (R2 = 0.02, P < .05). CONCLUSIONS: This study shows that few neutral mechanical alignments are finally obtained after TKA by conventional technique. A major number of patients present a postoperative modification of their constitutional phenotype. Functional results at 2 years of follow-up appear to be improved by the restoration of the CPAK phenotype, JLO, and aHKA. LEVEL OF CLINICAL ART EVIDENCE: III, Retrospective Cohort Study.

Anterior cruciate ligament injuries in elite ski jumping reliably allow return to competition but severely affect future top performance.

PURPOSE: In recent years, anterior cruciate ligament (ACL) injuries have been frequently observed in ski jumping. However, available data in this discipline are very scarce. Therefore, the purpose of this study was to investigate whether an ACL injury in elite-level ski jumping limits the performance level after ACL reconstruction (ACLR). METHODS: Both male and female elite-level ski jumpers from five national A-teams who suffered an ACL injury were identified retrospectively by searching available media reports and Fédération Internationale de Ski (FIS) database. World Cup (WC) results and time-out-of-competition before ACL injury and after ACLR were compared. Only athletes who suffered the injury during or after the 2009-2010 season and who participated in at least one WC competition before the injury were included in this study. The level of athletes' performance from two full seasons before until three seasons after the injury was compared. RESULTS: Eighteen elite-level ski jumpers (11 males/seven females) were eligible for the study. All male and four female athletes returned to professional competition after ACLR. One female athlete ended her career due to prolonged recovery and two have not yet recovered due to a recent injury. The mean return-to-competition (RTC) time was 14.6 months in males and 13.5 months in females. The mean WC placement decreased after the ACL injury: two seasons before injury the mean position was 17.9 ± 11.0 (n = 12), one season before it was 22.4 ± 12.8 (n = 15). After recovery, the mean placement in seasons 1-3 was: 26.4 ± 8.9 (n = 7), 25.7 ± 10.3 (n = 13), 33.6 ± 12.2 (n = 10) (p = 0.008). Among the athletes returning to competition, only six males and three females reached their preinjury level and only one male and one female (compared to seven males and three females preinjury) reached an individual top-3 placement after ACLR, accounting for less than 10% of podiums compared to preinjury. CONCLUSION: Only 60% of the professional ski jumpers reached the preinjury level and less than 15% reached a top-3 placement after the ACL injury. These results support the fact that ACL tear during a ski jumping career may be a significant factor limiting high-level performance. In terms of clinical relevance, the findings implicate the need to analyse the reasons of these very low rates of return to elite-level performance, to analyse ACL injury and RTC rates at lower levels of performance and to develop specific prevention strategies in order to reduce the number of ACL injuries in this sport. LEVEL OF EVIDENCE: Level IV.

Presentation of an intraosseous suspensory fixation technique for pediatric and adult ACL reconstruction.

The aim is to present a technique for pediatric and adult ACL reconstruction using an intraosseous suspensory fixation. This technique uses a 4-strands hamstring graft fixed in the femoral tunnel, with a loop locked in a polyetheretherketone (PEEK) cage. The ACLip® device offers an inside-out drilling system and a closer fixation to the joint than an extracortical button fixation. The technique can be easily used both in adults and in skeletally immature patients. The first practical experience shows promising results regarding the safety and the effectiveness of the technique. Level of evidence: IV.

Case report: unusual posteromedial capsular lesion with posterior lateral meniscus root tear in two patients with constitutional genu recurvatum presenting after an acute ACL injury.

Ramp lesions of the medial meniscus and posterior lateral meniscus root tears (LMPRT) can be present simultaneously in up to 8% of patients undergoing anterior cruciate ligament (ACL) reconstruction. The prevalence of these complex and highly unstable meniscal tears increases exponentially with the severity of the injury. The posteromedial capsule (PMC) has often been disregarded in the past when discussing ligamentous and meniscal injuries, but the recent interest in ramp lesions has drawn surgeons' attention to the posteromedial structures of the ACL injured knee. While the meniscocapsular junction is commonly repaired in unstable ramp lesions, in the current literature there is no report regarding proximal PMC lesions, be they in isolation or associated with complex meniscal injuries.We report here two cases of proximal posteromedial capsular lesions associated with medial meniscus instability and posterior lateral root tears after ACL injury. The first case involves a meniscus ramp lesion associated with a proximal PMC tear and a posteromedial fluid collection in the muscle plane on magnetic resonance in a 22-year-old male soccer player. The second case involves a 21-year-old female soccer player who presented with a PMC lesion after hyperextension/valgus knee injury. The capsular lesions were repaired to restore capsular tension and improve medial meniscus posterior horn stability.

A systematic approach to managing complications after proximal tibial osteotomies of the knee.

Proximal tibial osteotomy (PTO) is an effective procedure for active and young adult patients with symptomatic unicompartmental osteoarthritis and malalignment. They were considered technically demanding and prone to various complications related to the surgical technique, biomechanical or biological origin. Among the most important are hinge fractures and delayed or non-healing, neurovascular complications, loss of correction, implant-related problems, patellofemoral complaints, biological complications and changes in limb length. Being aware of these problems can help minimizing their prevalence and improve the results of the procedure.The aim of this narrative review is to discuss the potential complications that may occur during and after proximal tibial osteotomies, their origin and ways to prevent them.

Meniscal Ramp Repair: Double-Row Anatomic Repair in Acute Anterior Cruciate Ligament Tears.

The surgical management of medial meniscus ramp lesions can be challenging. Currently, repairs are performed via a trans-notch view, combined with a single posteromedial working portal. This technique, however, does not allow for a direct and complete visualization of the structures being injured, making a precise appreciation of the injured structures, as well as an anatomical repair, difficult. To overcome this limitation, a 2-portal posteromedial approach has recently been described. It allows better visualization of the mediolateral extent of the tear and a precise identification of the injured structures. In this Technical Note, an anatomic repair technique using this approach is presented. It consists of a double-row of sutures to repair individually both the meniscotibial and meniscocapsular ligament, thus restoring the 2 main components of the posterior horn of the medial meniscus to their natural insertion site.

Improving the reliability of measurements in orthopaedics and sports medicine.

A large space still exists for improving the measurements used in orthopaedics and sports medicine, especially as we face rapid technological progress in devices used for diagnostic or patient monitoring purposes. For a specific measure to be valuable and applicable in clinical practice, its reliability must be established. Reliability refers to the extent to which measurements can be replicated, and three types of reliability can be distinguished: inter-rater, intra-rater, and test-retest. The present article aims to provide insights into reliability as one of the most important and relevant properties of measurement tools. It covers essential knowledge about the methods used in orthopaedics and sports medicine for reliability studies. From design to interpretation, this article guides readers through the reliability study process. It addresses crucial issues such as the number of raters needed, sample size calculation, and breaks between particular trials. Different statistical methods and tests are presented for determining reliability depending on the type of gathered data, with particular attention to the commonly used intraclass correlation coefficient.

The posterior cruciate ligament-posterior femoral cortex angle (PCL-PCA) and the lateral collateral ligament (LCL) sign are useful parameters to indicate the progression of knee decompensation over time after an ACL injury.

PURPOSE: The posterior cruciate ligament-posterior cortex angle (angle between the most vertical part of the anterolateral PCL bundle and the posterior diaphyseal cortex of the femur; PCL-PCA) is the most accurate approach to describe the PCL buckling phenomenon observed in anterior cruciate ligament (ACL)-deficient knees. The aim of this study was to determine whether the PCL-PCA is associated with chronicity of the ACL rupture, the meniscal status, preoperative knee laxity or imaging signs such as the lateral collateral ligament (LCL) sign or the posterior tibial slope (PTS) in ACL-injured knees. METHODS: Patients with a primary ACL reconstruction (ACLR) after physeal closure were selected retrospectively from a hospital-based ACL registry from 2015 to 2021. Exclusion criteria were: previous ipsilateral/contralateral knee surgery, previous ipsilateral ACL or meniscal tear, ipsilateral PCL and/or collateral ligament injuries or tibial plateau fracture. The ACL deficiency was defined as chronic if time from injury to MRI was > 6 months. The meniscal status was assessed during ACLR, separately for the medial and lateral meniscus, and classified into no tear, minor or major unstable tear. The MRI analyses included the assessment of the PCL-PCA and the LCL sign. PTS was assessed from the lateral plain radiographs of the injured knee. The side-to-side difference in anterior tibial translation (ATT) at 200N was obtained with the GNRB. RESULTS: Eighty-two patients (forty-eight males/thirty-four females) were included in this study. The median PCL-PCA was 16.2° (Q1-Q3: 10.6-24.7) and differed between acute (18.4°) and chronic (10.7°) injuries (p < 0.01). The median PCL-PCA was significantly lower (- 4.6°) in patients with a positive LCL sign (p = 0.03) No significant association could be found between PCL-PCA and meniscal status, PTS or preoperative anterior knee laxity (Lachman, pivot shift and ATT in millimetres). CONCLUSION: The PCL-PCA was significantly lower in chronic ACL injuries and in patients with a positive LCL sign, indicating a higher buckling phenomenon of the PCL in these patients. These results support the fact that PCL-PCA and the LCL sign may be useful parameters to indicate the progression of knee decompensation over time after an ACL injury, and therefore may constitute a helpful tool to optimise treatment choice and timing of ACL reconstruction if necessary. LEVEL OF EVIDENCE: III.

Construction and validation of a functional diagnostic score in anterior cruciate ligament ruptures of the knee in the immediate post-traumatic period. Preliminary results of a multicenter prospective study.

INTRODUCTION: Knee ligament injuries are frequent and their number is constantly increasing with the development of sports activities. Dynamic knee maneuvers usually make it possible to diagnose anterior cruciate ligament (ACL) injuries but they remain difficult to perform in the early post-traumatic phase. This leads to the almost systematic use of MRI scans, many of which turn out to be superfluous. The aim of this study was to construct a screening score based solely on history-taking, in order to help diagnose ACL injuries, and to define thresholds that could help inform recommendations for MRI usage. The hypothesis was that this score could distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries. MATERIAL AND METHODS: This prospective multicenter study included 166 patients. Patients were included if they were between 18 and 55 years of age, with knee trauma that had occurred in the last 10 days, and without a bone fracture on standard radiographs. They were excluded if the trauma required immediate surgical management and if they had a history of knee trauma. The screening score was completed by the physician. The score included the following items: assessment of pain, immediate post-traumatic functional impairment, notion of a "pop", feeling of instability and presence of a swelling. An MRI was systematically performed and the patient consulted a referring physician to compare the initial score with the diagnosis. RESULTS: Eighty-six patients had an injured ACL and 80 had a healthy ACL. Two thresholds could be identified. For a score lower than 4, the risk of an ACL injury was low with a sensitivity of 96% and a negative predictive value of 87%. For a score above 8, the ACL injury was highly probable with a specificity of 88% and a positive predictive value of 83%. DISCUSSION/CONCLUSION: The score was able to distinguish a population of patients with a ruptured ACL from a population of patients with other knee injuries. These preliminary results confirm that the selected items are relevant and that the score can help improve the diagnostic orientation of patients with recent knee trauma. Increasing the sample size in combination with an analysis of influencing factors will determine whether the performance of this score can be refined. LEVEL OF EVIDENCE: II prospective multicenter study.

Ramp Lesions of the Medial Meniscus.

PURPOSE OF REVIEW: To provide an overview of the recent scientific literature about ramp lesions of the medial meniscus and to summarise the current evidence on their prevalence, classification, biomechanics, surgical techniques and clinical outcomes. RECENT FINDINGS: Ramp lesions may be present in more than 1 patient undergoing ACL reconstruction out of 5 and almost half of the medial meniscal tears observed in this population. Due to the risk of persistent anterior and rotational laxity after ACL reconstruction, their repair has been advocated. There is no general agreement to date on whether and when ramp lesions should be treated surgically. Comparative studies have failed to show that the repair of stable lesions was superior in comparison to nonoperative approaches. A lower failure rate and secondary meniscectomy has been reported with a suture hook repair through the posteromedial portal in comparison with an all-inside technique. Furthermore, reconstructions of the anterolateral complex in association with ACL reconstruction may have a protective effect on ramp repair. Ramp lesions of the medial meniscus in ACL-injured knees cannot be neglected anymore. Given their novelty, their clinical impact has not been fully assessed yet, but the evidence is growing that they need to be systematically identified and eventually repaired, for which they require advanced surgical knowledge. There is, to date, no consensus on whether and when ramp lesions should be treated surgically. Their subtypes, size and stability may influence the decision-making process.

MCID and PASS in Knee Surgeries. Theoretical Aspects and Clinical Relevance References.

The application and interpretation of patient-reported outcome measures (PROM), following knee injuries, pathologies, and interventions, can be challenging. In recent years, the literature has been enriched with metrics to facilitate our understanding and interpretation of these outcome measures. Two commonly utilized tools include the minimal clinically important difference (MCID) and the patient acceptable symptoms state (PASS). These measures have demonstrated clinical value, however, they have often been under- or mis-reported. It is paramount to use them to understand the clinical significance of any statistically significant results. Still, it remains important to know their caveats and limitations. In this focused report on MCID and PASS, their definitions, methods of calculations, clinical relevance, interpretations, and limitations are reviewed and presented in a simple approach.

The anterior cruciate ligament injury severity scale (ACLISS) is an effective tool to document and categorize the magnitude of associated tissue damage in knees after primary ACL injury and reconstruction.

PURPOSE: To develop a tool allowing to classify the magnitude of structural tissue damage occurring in ACL injured knees. The proposed ACL Injury Severity Scale (ACLISS) would provide an easy description and categorization of the wide spectrum of injuries in patients undergoing primary ACL reconstruction, reaching from isolated ACL tears to ACL injuries with a complex association of combined structural damage. METHODS: A stepwise approach was used to develop the ACLISS. The eligibility of each item was based on a literature search and a consensus between the authors after considering the diagnostic modalities and clinical importance of associated injuries to the menisci, subchondral bone, articular cartilage or collateral ligaments. Then, a retrospective analysis of associated injuries was performed in 100 patients who underwent a primary ACL reconstruction (ACLR) by a single surgeon. This was based on acute preoperative MRI (within 8 weeks after injury) as well as intraoperative arthroscopic findings. Depending on their prevalence, the number of selected items was reduced. Finally, an analysis of the overall scale distribution was performed to classify the patients according to different injury profiles. RESULTS: A final scoring system of 12 points was developed (12 = highest severity). Six points were attributed to the medial and lateral tibiofemoral compartment respectively. The amount of associated injuries increased with ACLISS grading. The median scale value was 4.5 (lower quartile 3.0; higher quartile 7.0). Based on these quartiles, a score < 4 was considered to be an injury of mild severity (grade I), a score between ≥ 4 and ≤ 7 was defined as moderately severe (grade II) and a score > 7 displayed the most severe cases of ACL injuries (grade III). The knees were graded ACLISS I in 35%, ACLISS II in 49% and ACLISS III in 16% of patients. Overall, damage to the lateral tibiofemoral compartment was predominant (p < 0.01), but a proportional increase of tissue damage could be observed in the medial tibiofemoral compartment with the severity of ACLISS grading (p < 0.01). CONCLUSIONS: The ACLISS allowed to easily and rapidly identify different injury severity profiles in patients who underwent primary ACLR. Injury severity was associated with an increased involvement of the medial tibiofemoral compartment. The ACLISS is convenient to use in daily clinical practice and represents a feasible grading and documentation tool for a reproducible comparison of clinical data in ACL injured patients. LEVEL OF EVIDENCE: Level III.

Lateral-medial asymmetry of posterior tibial slope and small lateral tibial plateau articular surface depth are morphological factors of lateral meniscus posterior root tears in ACL-injured patients.

PURPOSE: To investigate whether knee morphological features, patient characteristics, and intraoperative findings are associated with a lateral meniscus (LM) posterior root tear (LMPRT) in anterior cruciate ligament (ACL) injuries with the integrated data from two academic centres. METHODS: This retrospective study used registry data acquired prospectively at two academic centres. Patients with ACL reconstruction (ACLR) with LMPRT and no other LM injury were selected (LMPRT group) from each database. The control group included patients who underwent ACLR without LM tears. Patients were matched to the LMPRT group according to age and gender (1:1). Morphological factors evaluated on preoperative magnetic resonance image scans included lateral femoral condyle (LFC) anterior-posterior diameter, height, and depth; lateral tibial plateau (LTP) articular surface (AS) depth and sagittal plane depth; and lateral and medial posterior tibial slopes (PTSs). LFC height and depth ratios, LTP AS depth and sagittal plane depth ratios, and lateral-to-medial slope asymmetry were computed from previous measurements. Patient characteristics and intraoperative findings were extracted and compared between both groups. RESULTS: The study included 252 patients (126 in each group). The lateral-medial asymmetry of PTS was greater in the LMPRT group (1.2° vs 0.3°, p < 0.05), and the LTP AS depth was smaller in the LMPRT group (31.4 mm vs 33.2 mm, p < 0.01). There were no differences in LFC morphology between the control and LMPRT groups. Pivot shift grade (p < 0.05), percentage of complete ACL tears (p < 0.05), and medial meniscus ramp lesions (p < 0.05) were significantly higher in the LMPRT group. CONCLUSION: LMPRT was associated with significantly increased lateral-medial asymmetry of PTS and significantly smaller LTP AS depth. LMPRT was also associated with an increase in the preoperative pivot shift grade and the presence of a medial meniscus ramp lesion. These morphological characteristics are rather simple to measure and would serve as helpful indicators to preoperatively detect LMPRT, which is frequently challenging to diagnose preoperatively. LEVEL OF EVIDENCE: Level III.