ACL-deficient Knee Research Articles

Changes in the Elongation Pattern of the Medial Collateral Ligament During a Single-Leg Squat After Anterior Cruciate Ligament Reconstruction.

An anterior cruciate ligament (ACL) tear impairs knee biomechanics in daily activities and potentially breaks the synergy among other knee ligaments. Previous studies have demonstrated that the biomechanics of collateral ligaments is influenced by ACL deficiency. To investigate changes in the elongation patterns of the medial collateral ligament (MCL), lateral collateral ligament (LCL), and posterior cruciate ligament (PCL) during the execution of a single-leg squat before and after ACL reconstruction. Descriptive laboratory study. A total of 16 patients (mean age, 24.9 ± 8.5 years) with ACL deficiency were enrolled in the study. Magnetic resonance imaging scans of the affected knees were used to produce 3-dimensional models of the tibia and femur and identify insertion sites of the MCL, LCL, and PCL. Motion capture of a single-leg squat was performed through a biplanar radiographic system. Data were acquired before ACL reconstruction and at a minimum of 18 months (mean, 22.9 ± 4.1 months) postoperatively. The centroids of the ligaments' insertions were used to calculate the length of the investigated structures during the squat task. Absolute length (L), absolute length increase from the orthostatic resting position (ΔL), and relative length increase (ΔL%) were computed for each ligament, and preoperative and postoperative data were compared using the paired Student t test. The intraclass correlation coefficient was used to determine the reliability of the ligament insertion's identification and kinematics between 2 independent observers. Significant differences were found for the MCL in absolute length increase (P = .047; Cohen d = 0.60) and relative length increase (P = .043; Cohen d = 0.61) from rest between preoperatively and postoperatively (ΔL pre = 1.0 mm; ΔL post = -1.1 mm; difference = 2.1 mm) at 0° to 30° of knee flexion during the descending phase of the single-leg squat. No differences were seen in the elongation patterns of the LCL or PCL from before to after ACL reconstruction. The MCL was significantly longer between 0° and 30° in ACL-deficient knees compared with ACL-reconstructed knees during the descending phase of a single-leg squat. No differences were identified for the LCL or PCL. Early ACL reconstruction could have a protective effect on the MCL in combined ACL and MCL lesions.

Is Trochlear Dysplasia Associated with a High Prevalence of Repaired Anterior Medial Portal Lesions in Anterior Cruciate Ligament-Deficient Knees?

Abstract Introduction Meniscal tears, especially in the medial meniscus, are common in anterior cruciate ligament (ACL) injuries. Repaired anterior medial portal (RAMP) lesions, specific meniscal injuries associated with ACL ruptures, affect the peripheral attachment of the posterior horn of the medial meniscus. While the relationship between femoral trochlear morphology and ACL tears is established, its association with RAMP lesions remains unexplored. This study investigates the association between femoral trochlear morphology and RAMP lesions in ACL-deficient knees using magnetic resonance imaging (MRI) and evaluates MRI's accuracy against arthroscopy. Methods This hospital-based, cross-sectional observational study was conducted in a tertiary care center over 18 months. It included 126 adult patients who underwent arthroscopic ACL reconstruction and had preoperative MRI. Variables included age, gender, body mass index, trauma nature, and various MRI parameters, including femoral trochlear morphology and presence of RAMP lesions. MRI findings were compared to arthroscopic findings to evaluate diagnostic accuracy. Results RAMP lesions were detected in 21 participants (16.7%) via MRI and 28 participants (22.2%) via arthroscopy. MRI showed 71.4% sensitivity and 99.0% specificity for detecting RAMP lesions. No significant association was found between femoral trochlear morphology and RAMP lesions. However, medial tibial slope (TS) and posterior medial tibial bone edema (PMTBE) were significantly associated with RAMP lesions. The agreement between MRI and arthroscopy was high (Cohen's kappa = 0.773, p < 0.001). Conclusion This study found no significant association between femoral trochlear morphology and RAMP lesions in ACL-deficient knees. Instead, medial TS and PMTBE were significant predictors. MRI proved to have high specificity but moderate sensitivity compared to arthroscopy.

Approaching ramp lesions from the different world of posterior knee compartment: A review of evidence with a proposal of a new classification and treatment

AbstractRamp lesions (RLs) are peripheral lesions that occur in the posterior part of the medial meniscus or where it attaches to the joint capsule. The classification of the medial meniscus RLs has been the focus of numerous studies and publications. This review provides an overview of RL's current classification and treatment options in anterior cruciate ligament deficient knees. The study also aims to present a more practical classification system for RLs to assist in treatment decision‐making. For the first time, we also presented a new surgical treatment for incomplete inferior and double‐complete RL based on the posterior knee arthroscopy that provides direct access to the posterior meniscal borders, enabling effective treatment and stronger biomechanical repair.Level of EvidenceLevel V.

Fixed-Bearing Medial Unicompartmental Knee Arthroplasty: New Indications and the Anterior Cruciate Ligament-Deficient Knee

The anterior cruciate ligament (ACL)-deficient osteoarthritic knee is a challenging disease entity which requires careful thought to restore function and return to activities. Advancements in technology and surgical techniques have expanded indications for unicompartmental knee arthroplasty (UKA), to include ACL-deficiency in select patients. An improved understanding of the ACL-deficient osteoarthritic knee can aid in clinical and surgeon decision-making to restore knee function. This review will discuss current practice guidelines for the ACL-deficient knee with single-compartment osteoarthritis including pathoanatomy, indications, contraindications, technical considerations, and clinical outcomes.

The Fibular Collateral Ligament Is a More Important Restraint to Varus Laxity Compared to the Anterolateral Complex in the Anterior Cruciate Ligament–Deficient Knee in a Cadaveric Biomechanical Study

PurposeThe purpose of this study was to compare the influence of the fibular collateral ligament (FCL) and the anterolateral complex (ALC) on varus knee laxity in paired anterior cruciate ligament (ACL)-deficient cadaveric knees using varus stress radiographs. MethodsVarus laxity in nine paired (N=18, mean age 73.8 years) human cadaveric knees was assessed using varus stress radiographs with a 12 Nm varus stress applied at 20° of knee flexion. All knees underwent testing in the intact state and following ACL sectioning. One knee of each pair was randomly assigned to undergo FCL sectioning and the contralateral knee was assigned to undergo ALC sectioning (anterolateral ligament [ALL] followed by the Kaplan fibers). ResultsBoth FCL sectioning and ALC (ALL and the Kaplan fibers) sectioning resulted in increased lateral compartment gapping compared to the intact state, 2.44 mm and 1.13 mm, respectively. ALL sectioning with intact Kaplan fibers did not result in increased lateral compartment gapping. Paired knee comparison revealed a significantly greater influence of the FCL than the ALC in restraining lateral compartment gapping under an applied varus stress (p=0.0003). ConclusionsSectioning the FCL resulted in significantly greater lateral compartment gapping under a varus stress than combined sectioning of the ALL and Kaplan fibers in an ACL deficient knee, although both scenarios resulted in significantly increased gapping compared to the intact state. Sectioning of the ALL with intact Kaplan fibers did not result in increased lateral compartment gapping. Clinical RelevanceThe FCL is the most important structure in restraining varus laxity in the ACL deficient knee and the ALC is of secondary importance in restraining varus laxity. In ACL deficient patients with a high-grade pivot shift, mild varus laxity on clinical examination, and an intact FCL on MRI, injury to the anterolateral complex should be considered and may be evaluated with varus stress radiographs. This study validates prior biomechanical studies of FCL deficiency and demonstrates that approximately 1 mm increase in lateral compartment gapping on varus stress radiographs may occur secondary to ALC injury and clinicians should be aware of this when considering treatment for ACL deficient patients with high-grade anterolateral laxity.

Posterior Cruciate Buckling Angle Variations Are Associated with Different Patterns of Medial Meniscus Tears in Anterior-Cruciate-Deficient Knees: Results of a Prospective Comparative Magnetic Imaging Resonance Study.

The diagnosis of anterior cruciate ligament (ACL) tear relies on clinical evaluation and magnetic resonance imaging (MRI). Direct and indirect signs of ACL tear have been described with MRI evaluation. Posterior cruciate ligament (PCL) buckling has been described as an indirect radiographic sign of an ACL tear. The aim of the present study was to assess the variations in PCL buckling angles in patients with ACL tears and in patients with isolated lesions in the posterior horn of the medial meniscus. In addition, the influence of different patterns of medial meniscus tears in ACL-deficient knees was investigated. Finally, the influences of risk factors such as tibial slope, delay from injury to surgery, absence of medial meniscus tear, degree of Lachman and pivot shift testing were also assessed. This was a cohort study. A total of 154 patients (78 in the group with ACL tear and 76 in the control group) were assessed with MRI and lateral weight-bearing X-ray to assess PCL buckling angle and tibial slope by two independent observers. The presence of a medial meniscus bucket handle or ramp lesion of the medial meniscus was assessed and recorded at the time of surgery. PCL buckling angle measurement was highly reliable, with an ICC of 0.866 and 0.894, respectively, in the study group and the control group for interobserver reliability. The intrarater reliability was found to be high in PCL buckling angle for the study group [ICC = 0.955] and the control group [ICC = 0.943]. The mean angle in patients with ACL tear was 110.7 ± 15.2° and 115.3 ± 16.2° (for the two examiners) and 111.4 ± 12° and 114 ± 14.5° (for the two examiners) in patients with an intact, healthy ACL. An association emerged between bucket handle tears of the medial meniscus (p = 0.010) and a decreased PCL buckling angle and between ramp lesions of the medial meniscus and increased PCL buckling angle both (p = 0.024). Good inter- and intraobserver reliability for the measurement of the PCL buckling angle was observed. Increased PCL buckling angle values were observed in patients with concomitant ACL and bucket handle tears of the medial meniscus, while decreased angle values were observed in those who had ACL tear and ramp lesion of the medial meniscus. No statistically significant difference in the PCL buckling angle emerged between patients with ACL tears and those who had a healthy, intact ACL.

Clinical Outcomes Following Treatment of Ramp Lesion during Anterior Cruciate Ligament Reconstruction (Systematic Review and Meta-Analysis)

Abstract Background Ramp lesion is defined as a vertical longitudinal detatchment of PHMM due to meniscocapsular ligament tears that is not greater than 2 cm in medio-lateral length resulting in separation of meniscocapsular or meniscotibial ligament. Aim of the Work The study aims to perform a systemic review and meta analysis concerning outcomes of ramp lesion repair during ACL reconstruction. Methodology Systematic review and Meta-analysis on Patients with ramp lesion undergoing ACL reconstruction and ramp lesion treatment with total of 387 studies matched our search terms. After exclusion of duplicates, 37 studies were initially included based on their Abstract. 27 studies were finally included. The average MINORS score of all non-randomised studies was 8.7/16 for non- comparative studies and 16.9/24 for comparative studies, respectively. Results Our results suggest that medial meniscus repair associated with ACL reconstruction may restore meniscal function by adjusting the anteroposterior length of the torn medial meniscus. Our data demonstrate that more than 75% of medial meniscal tears in the ACL-deficient knee occur in the peripheral posterior horn. If we assume that the anatomy as described by Hughston and Eilers is correct, then care should be taken when addressing these tears, because a strong repair is needed to preserve the stability of the knee. Conclusion MRI demonstrated moderate sensitivity and excellent specificity in the diagnosis of ramp lesion in patients with ACL tear. According to the current systematic review, ramp lesions are common in ACL-deficient knees and are often missed through standard anterior portals. Exploration of the meniscocapsular complex via an additional posteromedial portal is recommended, if MRI suggests a lesion in this area or if instability is present at probing. If the posteromedial view still does not reveal any lesion despite significant instability, soft-tissue debridement might uncover hidden lesions (meniscotibial ligament disruptions). Ramp lesion repair leads to a significant improvement of subjective knee scores, regardless of the specific fixation technique. For stable ramp lesions, trephination and abrasion might be equivalent to ramp lesion repair in terms of postoperative stability.

Fixed-Bearing Lateral Unicompartment Knee Arthroplasty in Degenerative ACL-Deficient and ACL-Intact Knees: A Matched Pair Analysis

BackgroundAnterior cruciate ligament (ACL)-deficient knees are no longer considered a contra-indication for unicompartment knee arthroplasty (UKA). The purpose of this study was to determine if patients who had an ACL-deficient knee who underwent lateral UKAs had similar mean 10-year outcomes compared to ACL-intact lateral UKA knees. MethodsPatients who underwent a lateral UKA with ACL deficiency by a single surgeon between 2004 and 2016, were identified. Preoperative magnetic resonance images (MRI) were utilized to identify a torn or absent ACL in all knees. The absence of an ACL was confirmed during arthroscopy prior to UKA. Patients were matched 1:2 based on age and sex with patients who underwent lateral UKA where the ACL was intact. The primary patient-reported outcome variable was survival without conversion to total knee arthroplasty. Secondary outcomes included Veterans Rand (VR)-12, the Lysholm score, the Knee Osteoarthritis Outcome Score (KOOS) Activities of Daily Living subscale, and Sport subscale. A power analysis showed that 14 patients were needed to identify differences of 10 points on the KOOS score with a power of 80%(p=0.05). ResultsThe cohort of ACL-deficient lateral UKA patients included 4 men and 12 women (43 to 82 years of age). The matched control group included 32 patients. The mean age of both groups was 67 years (range, 43 to 85). There were two patients in the ACL-deficient group who failed. At 10 years, survivorship in the ACL-deficient group was 85%, while survival in the ACL-intact group was 100% (P = 0.035). At an average follow-up of 11 years (range, 4 to 19.6), there was no difference in outcome scores between ACL-deficient and ACL-intact patients. ConclusionFixed-bearing lateral UKA in the ACL-deficient knee resulted in lower survival compared to patients who had an intact ACL. Patient-reported outcomes were similar in both groups. The ACL-deficient patient who wishes to undergo lateral UKA should be counseled on the lower survival.

Steep medial posterior tibial slope angle and ramp lesion are independent risk factors for an increase in quantitatively measured pivot shift in patients with ACL-deficient knees.

Delayed anterior cruciate ligament (ACL) reconstruction often causes residual anterolateral rotatory instability (ALRI) and consequent knee osteoarthritis, warranting the recommendation of early ACL reconstruction within 6 months after injury. Nonetheless, some cases show notable instability, even shortly after injury. The purpose of this study was to identify risk factors for an increase in quantitatively measured pivot shift in patients with ACL-deficient knees within 6 months after injury. Patients with primary ACL reconstruction within 6 months after injury and quantitative triaxial accelerometer measurements of preoperative pivot shift were included. Descriptive statistics were calculated for 11 independent variables (age, gender, time from injury to surgery, KT-1000, knee extension angle, lateral and medial posterior tibial slope angle, medial and lateral meniscus tears, ramp lesion and Tegner active scale). A single regression analysis was performed on the 11 items and acceleration during the pivot shift, and a multiple regression analysis was performed for items with p value less than 0.1. Overall, 111 patients met the inclusion criteria. Single regression analysis showed that medial posterior tibial slope angle, medial meniscus tear and ramp lesion were significantly correlated with acceleration during the pivot shift (p < 0.001, p = 0.04 and p = 0.001). Multiple regression analysis identified medial posterior tibial slope angles and ramp lesions as independent factors for increased preoperative pivot shift (p = 0.005 and 0.01). A steep medial posterior tibial slope angle and ramp lesion were independent risk factors for increased quantitatively measured pivot shift in patients with ACL-deficient knees. Level IV, case series study.

Effect of open vs. closed kinetic chain exercises in ACL rehabilitation on knee joint pain, laxity, extensor muscles strength, and function: a systematic review with meta-analysis.

PROSPERO [CRD42023475230].

Reduced physiological extrusion of the medial meniscus in axial load-bearing condition in anterior cruciate ligament deficiency.

In this study, ultrasonography was used to measure medial meniscus (MM) extrusion under weight-bearing and nonweight-bearing conditions in both anterior cruciate ligament (ACL)-deficient and ACL-intact knee groups. This study aimed to determine the possible differences between these groups with an eventual impact on meniscal tears in ACL-deficient knees. A total of 107 patients who underwent ACL reconstructive surgery between June 2022 and April 2023 were enroled. After applying exclusion criteria, 37 patients met the conditions for inclusion in the study and formed the ACL deficiency group (Group D). Of the 141 patients presenting to an outpatient clinic who agreed to have ultrasonography conducted on their nondiscomforting contralateral knee, 37 patients matched for age, sex, hip-knee-ankleangleand body mass indexwith Group D patients were selected for the ACL intact group (Group I). Ultrasonography was used to measure MM extrusion in weight-bearing and nonweight-bearing conditions for all participants. Seventy-four patients were included in the study (n = 37 per group). The supine position showed an MM extrusion of 1.2 ± 0.7 mm in Group I and 1.2 ± 0.7 mm in Group D (not significant). In the standing position, MM extrusion measured 2.0 ± 0.6 mm in Group I and 1.3 ± 0.8 mm in Group D. The difference in extrusion (Δextrusion) between the two positions was 0.8 ± 0.6 in Group I and 0.1 ± 0.2 in Group D, with statistical significance (p < 0.01). A consistent reduction in MM extrusion during weight-bearing was observed in patients with ACL deficiency, irrespective of the duration of ACL deficiency, age, sexand BMI. ACL deficiency did not significantly impact MM extrusion during nonweight-bearing conditions; however, less MM extrusion was observed in response to axial loading conditions. These findings indicate altered MM biomechanics due to increased anterior-posteriormeniscal motion and rotational instability after ACL injury. Level III.

Long Term Comparison of Hamstring Tendon Autograft and Tibialis Anterior Tendon Allograft Use in ACL Reconstruction

Aim: In the early 2000s, the optimal graft for anterior cruciate ligament (ACL) reconstruction was a subject of uncertainty. Today, autografts have become the gold standard in this procedure. Aim of this study is to contribute to the existing knowledge by conducting a comprehensive comparison of the long-term clinical outcomes between hamstring allografts and anterior tibialis tendon allografts (ATT) in the context of ACL reconstruction. Material and Method: This study was conducted based on individuals who were operated on with the diagnosis of symptomatic ACL rupture 10 years ago. Participants were randomly assigned to undergo ACL reconstruction using either hamstring autografts or anterior tibialis allografts. All allografts were procured from a single tissue bank, underwent aseptic processing, and were fresh-frozen without terminal irradiation. Patient assessments included questionnaires based on the Lysholm knee scoring scale (LKSS) and the International Knee Documentation Committee (IKDC) subjective knee score. Objective functional tests, such as the Lachman test and pivot-shift, were performed, accompanied by a comprehensive physical examination of the knee. Results: A total of 60 patients, comprising 58 males and 2 females, with a mean age of 29.48±6.2, were included in the study. Predominant symptoms reported were pain and giving-way phenomena. Significantly different LKSS values were observed between the preoperative and postoperative periods for both anterior tibialis allograft and hamstring autograft patients (p

In Vitro Assessment of Knee Joint Biomechanics Using a Virtual Anterior Cruciate Ligament Reconstruction.

Understanding the biomechanical impact of injuries and reconstruction of the anterior cruciate ligament (ACL) is vital for improving surgical treatments that restore normal knee function. The purpose of this study was to develop a technique that enables parametric analysis of the effect of the ACL reconstruction (ACLR) in cadaver knees, by replacing its contributions with that of a specimen-specific virtual ACLR that can be enabled, disabled, or modified. Twelve ACLR reconstructed knees were mounted onto a motion simulator. In situ ACLR graft forces were measured using superposition, and these data were used to design specimen-specific virtual ACLRs that would yield the same ligament force-elongation behaviors. Tests were then repeated using the virtual ACLR in place of the real ACLR and following that in ACL deficient knee by disabling the virtual ACLR. In comparison to the ACL deficient state, the virtual ACLRs were able to restore knee stability to the same extent as real ACLRs. The average differences between the anterior tibial translation (ATT) of the virtual ACLR versus the real ACLR were +1.6 ± 0.9 mm (p = 0.4), +2.1 ± 0.4 mm (p = 0.4), and +1.0 ± 0.9 mm (p = 0.4) during Anterior drawer, Lachman and Pivot-shift tests, respectively, which is small in comparison to the full ATT range of motion (ROM) of these knees. Therefore, we conclude that a virtual ACLR can be used in place of real ACLR during biomechanical testing of cadaveric knees. This capability opens the door for future studies that can leverage parameterization of the ACLR for surgical design optimization.

Chronic ACLD Knees with Early Developmental Cartilage Lesions Exhibited Increased Posterior Tibial Translation during Level Walking.

Early articular cartilage lesion (CL) is a vital sign in the onset of posttraumatic knee osteoarthritis (PTOA) in patients with anterior cruciate ligament deficiency (ACLD). Researchers have suggested that altered kinematics could accelerate CLs and, therefore, lead to the onset of PTOA. However, little is known about whether specific knee kinematics exist that lead to early CL in chronic ACLD knees. Level walking is the most frequent and relevant in vivo activity, which greatly impacts knee health. We hypothesized that the knee kinematics during level walking in chronic ACLD knees with early tibiofemoral CL would significantly differ from those of chronic ACLD knees without early tibiofemoral CL. Thirty patients with a chronic ACLD history, including 18 subjects with CLs and 12 subjects without CLs, and 35 healthy control subjects were recruited for the study from July 2020 to August 2022. The knee kinematic data during level walking were collected using a three-dimensional motion analysis system. The kinematic differences between groups were compared using statistical parametric mapping with one dimension for One-Way ANOVA. The cartilage statuses of the ACLD knees were assessed via MRI examination. The CLs distribution of subjects was evaluated using a modified Noyes scale and analyzed by chi-square tests. ACLD knees with CLs had significantly greater posterior tibial translation (7.7-8.0mm, 12%-18% gait cycle GC, p = 0.014) compared to ACLD knees without CLs during level walking. ACLD knees with CLs had greater posterior tibial translation (4.6-5.5mm, 0%-23% GC, p < 0.001; 5.8-8.0mm, 86%-100% GC, p < 0.001) than healthy controls during level walking. In the group of ACLD knees with CLs, CL is mainly located in the back of the tibia plateau and front of load bearing area of the medial femoral condyle (p < 0.05). Chronic anterior cruciate ligament deficient knees with cartilage lesions have increased posterior tibial translation compared to anterior cruciate ligament deficient knees without cartilage lesions and healthy subjects. The posterior tibial translation may play an important role in knee cartilage degeneration in ACLD knees. The increased posterior tibial translation and cartilage lesion characteristics may improve our understanding of the role of knee kinematics in cartilage degeneration and could be a helpful potential reference for anterior cruciate ligament deficient therapy, such as physical training to improve abnormal kinematic behavior.

Evaluating the Diagnostic Performance of MRI for Identification of Meniscal Ramp Lesions in ACL-Deficient Knees: A Systematic Review and Meta-Analysis.

Despite vigorous efforts to delineate the efficacy of magnetic resonance imaging (MRI) for the diagnosis of meniscal ramp lesions, there is still a great deal of uncertainty regarding its diagnostic performance. Therefore, we conducted a systematic review and meta-analysis to investigate the diagnostic performance of MRI for detecting ramp lesions in anterior cruciate ligament (ACL)-deficient knees. We performed a systematic search of MEDLINE via PubMed, Scopus, Web of Science, and Embase and included all articles, published before October 20, 2022, comparing the accuracy of MRI with that of arthroscopy as the gold standard for diagnosis of ramp lesions. We performed statistical analysis using Stata and Meta-DiSc software. Quality assessment of the included studies was performed using the QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2) tool. This meta-analysis evaluated 21 diagnostic performance comparisons from 19 original research articles (2,149 patients). The pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), and area under the summary receiver operating characteristic (SROC) curve for diagnosing a ramp lesion were 0.70 (95% confidence interval [Cl], 0.66 to 0.73), 0.88 (95% Cl, 0.86 to 0.89), 6.49 (95% Cl, 4.12 to 10.24), 0.36 (95% Cl, 0.28 to 0.46), 24.33 (95% Cl, 12.81 to 46.19), and 0.88, respectively. Meta-regression using different variables yielded the same results. MRI exhibited a DOR of 24.33 and moderate sensitivity, specificity, and accuracy for diagnosing ramp lesions in ACL-deficient knees. However, arthroscopy using a standard anterolateral portal with intercondylar viewing is recommended to confirm a diagnosis of a ramp lesion. Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Good clinical outcomes of anterior cruciate ligament reconstruction in patients over 60 years of age.

To evaluate the clinical outcomes following arthroscopic anterior cruciate ligament (ACL) reconstruction (ACLR) in patients over 60 years and to investigate the potential impact of preoperative osteoarthritis (OA) on these outcomes. A retrospective study included ACL-injured patients over 60 years who underwent primary arthroscopic ACLR between 2010 and 2020. The Lysholm score and the International Knee Documentation Committee (IKDC) score were assessed preoperatively and at the final follow-up. The Tegner activity scale was performed to evaluate patients' activity levels. Data on return to sports, patient satisfaction, subsequent injuriesand complications were collected. Preoperative radiographs were used to grade OA according to the Kellgrene-Lawrenceclassification. Correlation analysis between OA and clinical outcomes was performed. The rates of achieving the minimal clinically significant differenceand patient-acceptable symptoms statewere documented. A total of 37 patients were included in this study. The mean age at surgery was 62.3 ± 2.3 years, with a mean follow-up of 6.3 ± 3.2 years (range: 2.1-12.4). Patients showed statistically significant (all p < 0.001) improvements in the mean IKDC (38.9 ± 9.4-66.8 ± 12.5), Lysholm (48.8 ± 15.4-83.0 ± 12.8)and Tegner (1-3) scores. Fourteen patients (37.8%) returned to sports. No correlation was observed between the degree of preoperative OA and clinical outcomes (n.s.). Patients over 60 years with symptomatic ACL-deficient knees could benefit from ACLR, even when mild to moderate OA is present preoperatively. Level IV.

Test-retest reliability and concurrent validity assessment of a novel high-frequency sensor device for anterior tibial translation measurement in loaded and unloaded condition: an exploratory cross-sectional study

BackgroundMagnetic resonance imaging (MRI) and manual tests remain the standard for diagnosing anterior cruciate ligament (ACL) rupture. Furthermore, the passive knee displacement, also described as anterior tibial translation (ATT), is used in order to make decisions about surgery or to assess rehabilitation outcomes. Unfortunately, these manual tests are limited to passive situations, and their application to assess knee stability in loaded, weight-bearing positions are missing. Therefore, a new device with high-performance sensors and a new sensor setting was developed. The aim of this exploratory cross-sectional study was to assess the test-retest reliability of this new device in a first step and the concurrent validity in a second step.MethodsA total of 20 healthy volunteers were measured. Measurement consistency of the new device was assessed on the basis of reliability during Lachman test setting and in loaded position by artificial knee perturbation in a test-retest procedure. In a second step, the concurrent validity was evaluated with the Lachmeter® as a reference instrument. Intraclass correlation coefficient (ICC), standard error of measurement (SEM), the minimal detectable change (MDC) and Bland-Altman analysis were evaluated to assess the quality criteria.ResultsThe measurements with the new device during the Lachman test provided a mean ATT of 5.46±2.22mm. The SEM ranged from 0.60 to 0.69mm resulting in an MDC between 1.67 and 1.93mm for the new device. In the loaded test situation, the mean ATT was 2.11±1.20mm, with test-retest reliability also showing good correlation (r>0.83). The comparison of the two measurement methods with an ICC of (r>0.89) showed good correlation, which also underlines the reasonable agreement of the Bland-Altman analysis.ConclusionsThe evaluation of the test-retest reliability of the new device during the knee stability testing in passive situation as well as in a functional, loaded situation presented good reliability. In addition, the new device demonstrated good agreement with the reference device and therefore good validity. Furthermore, the quality criteria demonstrated the ability of the new device to detect the cut-off value (3-5mm) described in the literature for the diagnosis of ACL-deficient knees, which underlines the clinical relevance of this new device as a reliable and valid tool.

Arthroscopic Evaluation of Association of Meniscus Injuries in Patients with Anterior Cruciate Ligament Injuries

Background: The knee joint's stability relies significantly on the integrity of the meniscus and the anterior cruciate ligament (ACL). Chronic ACL tears can compromise knee stability, making the meniscus a crucial stabilizer. Understanding the prevalence and patterns of meniscus injuries associated with chronic ACL tears is essential for effective management. Objective: This study aimed to assess the arthroscopic evaluation of association of meniscus injuries in patients with anterior cruciate ligament injuries. Method: A retrospective analysis was conducted on thirty-three patients diagnosed with ACL injuries at MuMCH between January 2021 and December 2023. Patients aged 18-50 with ACL injuries, with or without meniscus damage, were included. Clinical evaluations, knee MRI scans, and diagnostic knee arthroscopies were performed. The study evaluated meniscus injuries associated with chronic ACL injuries and assessed outcomes using the modified Lysholm score. Results: The study revealed a predominant occurrence of meniscus injuries (70%) among participants, with a majority falling within the 38-47 years age bracket (45.45%) and a male majority (60%). Sports and accidental injuries accounted for 40% each, while road traffic accidents contributed 20%. Lateral meniscus tears were the most prevalent (30.30%), followed by combined medial and lateral meniscus tears (33.33%). Posterior horn tears were predominant, particularly in the medial meniscus. Conclusion: The study highlights a high incidence of meniscus injuries associated with chronic ACL tears, with medial meniscus injuries prevailing over lateral tears. Posterior horn tears were predominant, emphasizing the medial meniscus's significant role in knee stability. These findings underscore the importance of early detection and appropriate management of meniscus injuries in chronic ACL-deficient knees to prevent degenerative changes and optimize patient outcomes.

Leaf spring exercise: A safe quadriceps strengthening exercise after anterior cruciate ligament reconstruction

BackgroundLeg extensions should be avoided in the early stages after anterior cruciate ligament reconstruction because the force exerted by the quadriceps muscle leads to anterior tibial displacement. To allow for safe quadriceps training in the knee extension range during this period, we devised the leaf spring exercise, which involves placing subjects in the prone position with their knee slightly flexed and instructing them to perform maximum isometric quadriceps contractions while supporting the proximal region of the lower leg's anterior surface and immobilizing the femur's posterior surface to prevent lifting. The current study aimed to examine the safety of Leaf spring exercise by determining the femur–tibia relationship using ultrasound imaging. MethodsThis controlled laboratory study included patients with unilateral anterior cruciate ligament-deficient knees (8 men and 8 women; age, 24.2 ± 8.3 years) who were instructed to perform Leaf spring exercise of both lower limbs. We measured the femur–tibia-step-off, which indicates the distance between the last point of the medial and lateral condyles of the femur and posterior margin of the tibial plateau, as a parameter to evaluate anterior tibial displacement via ultrasound diagnostic device. Further, peak torque of the quadriceps muscle was calculated using force measurement device. FindingsNo difference in anterior tibial displacement and peak torque was observed between the uninjured and injured sides during Leaf spring exercise. InterpretationLeaf spring exercise may add some strain on the reconstructed anterior cruciate ligament; hence, it can be considered a safe quadriceps exercise in the knee extension range.

Changes in gait patterns after anterior cruciate ligament reconstruction in children.

Anterior cruciate ligament reconstruction (ACLR) in children is indicated to reduce recurrent knee instability and further damage to the joint. Postoperative modified gait pattern was reported in the adult population after ACLR. The aim of this study was to analyse gait abnormalities, and especially knee and ankle adaptations during gait in children after ACLR. A prospective study was performed between 2018 and 2022 on 50 children, aged nine to15years with unilateral ACL deficiency. Changes in gait pattern were evaluated by gait analysis before surgery and at the latest follow-up of 24months. Kinematic data of ACL-deficient limb were compared to contralateral limb and to those of a matched control group of healthy children. Compared to control group, knee flexion was decreased for both ACL-deficient and contralateral knee before surgery. Decreased knee flexion during gait cycle persisted at latest follow-up. Ankle kinematics showed decreased dorsal flexion for both ACL-deficient and contralateral limb before surgery. At latest follow-up, ankle kinematics were modified for ACL-reconstructed limbs only at initial contact and showed no significant difference for contralateral limb compared to the control group. In children with ACL injury, abnormal gait patterns persist twoyears after ligament reconstruction, in spite of extensive rehabilitation and no clinical complaints. These findings might guide neuromuscular training to improve clinical outcomes and reduce the rerupture rate.