Anterior Tibial Displacement Research Articles

Loop technique for anterior cruciate ligament reconstruction combined with anterolateral structure reinforcement: technical description and clinical results

PurposeWe describe a surgical technique for ACL reconstruction combined with anterolateral structure reinforcement and report early clinical follow-up results.MethodsThe semitendinosus and gracilis tendons are braided into 5 strands and the ACL femoral tunnel and tibial tunnel are created. The graft is passed through the tunnel with the use of a traction suture and the tibial end is fixed with absorbable interference screws at 30° of knee flexion. The ACL graft traction suture is used as an anterolateral reconstruction structure to pass through the proximal exit of the ACL femoral tunnel and then through the depth of the iliotibial bundle to the anterior to Gerdy’s tubercle, a bony tunnel is created from the anterior to Gerdy’s tubercle to the goose foot, and the traction suture is passed through this bony tunnel to form a Loop structure at 20° of knee flexion. Between March 2021 and May 2022 IKDC score, Lysholm score, and Tegner score were performed preoperatively and 6–12 months postoperatively in 24 consecutive patients who met the indications for this procedure and underwent surgery. The patient’s maximum flexion angle, the circumference of the thigh, and the stress X-ray between the operated and healthy knee were measured.ResultsPatients showed significant improvement in IKDC score, Lysholm score and Tegner score at a mean follow-up of 7 months postoperatively compared to preoperatively. No significant increase in anterior tibial displacement was found between the patient’s operated side and the healthy side.ConclusionThe Loop technique ACLR combined with ALSA can be used in patients with an ACL tear combined with a high degree of positive pivot shift. The patient’s subjective perception was significantly improved from the preoperative period and knee stability was restored.Level of evidenceIV, therapeutic study.

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.

Subregional analysis of joint stiffness facilitates insight into ligamentous laxity after ACL injury.

Purpose: Increased incidence of anterior cruciate ligament injuries has amplified the need for quantitative research in clinical and academic settings. We used a novel digital arthrometer to measure knee laxity in healthy people and patients with anterior cruciate ligament injuries. Changes in stiffness were also assessed to develop new indicators for detecting anterior cruciate ligament injury. The purpose of this study was to use arthrometer to measure the quantitative indicator of knee laxity, bringing clinicians a new perspective on how to identify injury to the ACL. Methods: In this cross-sectional study, anterior tibial displacement under continuous loading was measured using a novel digital arthrometer in 30 patients with unilateral anterior cruciate ligament injury and 30 healthy controls. Load-displacement curves were plotted, using real-time load and displacement changes. Stiffness was defined by the slope of the applied load to tibial displacement. Anterior tibial displacement and instantaneous stiffness values under different loads were compared. The restricting contribution of the anterior cruciate ligament transformed the displacement-stiffness curve from a sharp decrease to a stable increase, resulting in a minimum stiffness value. Using the minimum stiffness as the turning point, the load-displacement curve was divided into regions 1 and 2. The two regions' stiffness changes were compared. Based on the findings, receiver operating characteristic curves were plotted and the area under the curve was calculated to estimate the diagnostic accuracy. Results: Anterior tibial displacement was significantly greater in the anterior cruciate ligament injury group than in the controls under each 10-N increase load (p < 0.05). In the anterior cruciate ligament injury group, instantaneous stiffness was significantly lower on the injured side than on the healthy side (p < 0.05). In the two regions of the load-displacement curve, stiffness was significantly lower in the anterior cruciate ligament injury group than in the control group (all, p < 0.05). Receiver operating characteristic curves were plotted, using changes in stiffness under the two regions in both groups. Stiffness in region 2 had the largest area under the curve (0.94; 95% CI, 0.88-0.99). Using the cut-off value of 9.62N/mm to detect ACL injury, the sensitivity and specificity were 93% and 82%, respectively. Conclusion: Our investigation of ligament stiffness provides novel insights into the properties of knee laxity. Stiffness in the later stages of increased loading <9.62N/mm could be a valid indicator for identifying knee laxity.

The effect of different posterior inclinations of tibial component on tibiofemoral contact pressures after unicompartmental knee arthroplasty

BackgroundDifferent posterior inclinations of tibial component after unicompartmental knee arthroplasty (UKA) may lead to different biomechanical characteristics of the knee joint. This finite element study was designed to investigate the tibiofemoral contact pressures after UKA with different posterior inclinations of tibial component.MethodsFinite element model of a healthy knee joint was constructed, and mobile-bearing (MB) UKA models with 5 different posterior inclinations (3°, 5°, 7°, 9° and 11°) of tibial components were simulated. The maximum contact pressures of tibial plateau cartilage in the lateral compartment and polyethylene insert in the medial compartment were calculated based on the ground reaction force and the angle of the knee flexion obtained by 3D motion capture system.ResultsThe loading ratio of medial and lateral compartments during standing stance (medial 54.49%, lateral 45.51%) and tibial anterior displacement (134 N, 3.89 mm) of healthy knee was basically consistent with previous experimental data. The maximum contact pressures of the medial meniscus and lateral tibial plateau cartilage of the healthy knee during standing stance were 2.14 MPa and 1.57 MPa, respectively. At the static standing phase, the maximum contact pressures of the polyethylene insert decreased from 17.90 to 17.29 Mpa, and the maximum contact pressures of the tibial plateau cartilage in the lateral compartment increased from 0.81 to 0.92 Mpa following an increase in the posterior inclination of the tibial component. At the first peak of ground reaction force, the maximum contact pressures of polyethylene insert increased from 22.37 to 25.16 MPa, and the maximum contact pressures of tibial plateau cartilage in the lateral compartment increased from 3.03 to 3.33 MPa, with the increase in the posterior inclination of the tibial component. At the second peak of ground reaction force, the maximum contact pressures of polyethylene insert decreased from 2.34 to 2.22 MPa with the increase in posterior inclination of tibial component.ConclusionThe preoperative and postoperative finite element models of MB UKA were well established. The results showed that the maximum contact pressures of the polyethylene insert did not change significantly with the increase in the posterior inclination of the tibial prosthesis, while the maximum contact pressures of the tibial plateau cartilage of the lateral compartment increased when the posterior inclination of the tibial prosthesis was > 7°. Our results also show that the maximum contact pressures were greater with an excessive inclination angle (11°) of the tibial component, and the pressures of the tibial plateau cartilage in the lateral compartment were more concentrated on the posterior area. This study, therefore, proposes that excessive osteotomy should be avoided.

3D assessment of graft malposition after ACL reconstruction: Comparison of native and 11o'clock ligament orientations

BackgroundFemoral tunnel malposition makes up the majority of technical failures for ACL reconstructive surgery. The goal of this study was to develop adolescent knee models that accurately predict anterior tibial translation when undergoing a Lachman and pivot shift test with the ACL in the 11o’clock femoral malposition (Level of Evidence: IV). MethodsFEBio was used to build 22 subject-specific tibiofemoral joint finite element representations. To simulate the two clinical tests, the models were subject to loading and boundary conditions established in the literature. Clinical, historical control data were used to validate the predicted anterior tibial translations. ResultsA 95% confidence interval showed that with the ACL in the 11o’clock malposition, the simulated Lachman and pivot shift tests produced anterior tibial translations that were not statistically different from the in vivo data. The 11o’clock finite element knee models resulted in greater anterior displacement than those with the native (approximately 10o’clock) ACL position. The difference in anterior tibial translation between the native and 11o’clock ACL orientations was statistically significant. ConclusionClinically, by understanding the impact that ACL orientation has in anterior tibial displacement biomechanics, surgical interventions can be improved to prevent technical errors from occurring. The integration of this methodology into surgical practice not only allows for anatomical visualization prior to surgery, but also creates the opportunity to optimize graft placement, thus improving post-surgical outcomes.

Association between knee function and kinesiophobia 6 months after anterior cruciate ligament reconstruction.

[Purpose] Kinesiophobia after anterior cruciate ligament reconstruction has been identified as an inhibitor of return to sports. This study aimed to clarify the relationship between kinesiophobia and knee function 6 months after anterior cruciate ligament reconstruction when the patient intends to return to sports. [Participants and Methods] A total of 66 patients who underwent primary anterior cruciate ligament reconstruction (mean age 17.3 ± 2.6 years, 17 males and 49 females, Tegner activity score ≥7) were included in the study. The 11-item version of Tampa scale of kinesiophobia was used to evaluate kinesiophobia 6 months postoperatively. Knee function was evaluated with knee extension muscle strength, tibial anterior displacement, heel buttock distance, heel height difference, anterior knee pain score, and single-leg hop test. The relationship between Tampa scale of kinesiophobia, patient characteristics, and knee function was investigated. [Results] A low Anterior knee pain score and low single-leg hop test, male gender, and age were significant factors associated with kinesiophobia. [Conclusion] Kinesiophobia was associated with a low anterior knee pain score and low single-leg hop test 6 months after anterior cruciate ligament reconstruction. Patients with a low single-leg hop test score or severe pain may need rehabilitation to reduce kinesiophobia.

Effect of Ballistic Training on Pain, Range of Motion and Strength in Phase II Rehabilitation of ACL Reconstruction: A Research Protocol of a Randomised Controlled Trial

Introduction: An Anterior Cruciate Ligament (ACL) injury produces a 5-40% reduction in quadriceps strength over time. Neuromuscular electrical stimulation is used to help the quadriceps muscle weaken after ACL surgery. The ACL is the primary stabiliser for anterior tibial displacement and the secondary stabiliser for tibial rotation; an ACL-deficient knee can result in devastating consequences like articular cartilage injuries, meniscus tears, functional instability, and the risk of early-onset osteoarthritis. Following an ACL injury, the goal of ACL restoration is to restore functional knee stability. Journals have indicated an increased interest in combining ACL restoration with extraarticular augmentation in recent years. Several studies have demonstrated that the extra reconstruction not only protects the graft from high loads, but also enhances lateral rotational control. In patients with sore joints after ACL reconstruction, cryotherapy can help by releasing endogenous opiates and decreasing nerve conduction velocity. Exercise performance for the physical qualities of strength and power, like many other sports activities, has a short time element for successful performance. As a result, these workouts are performed at the highest possible speed in the least amount of time. Need for the study: There are many evidences that theraband exercises are essential for the patients with ACL reconstruction. Even in athletes, there are literature that proves ballistic training is essential for the patients with ACL reconstruction, but there is no literature for the ballistic training in normal population undergoing ACL reconstruction surgery. There is a strong need to perform a study and evaluate them. Aim: To find out effectiveness of ballistic training in phase II rehabilitation on the patients with ACL reconstruction. Materials and Methods: This randomised control trial will be conducted from May 2022 to May 2023 in the Outpatient and the Inpatient Department of Physiotherapy, Acharya Vinoba Bhave Rural Hospital, Sawangi (Meghe), Wardha, India, during which 100 patients with ACL reconstruction will be divided into two groups, one group will receive conventional therapy along with theraband exercises and another group will receive conventional therapy exercises along with ballistic training. Treatment will be given for eight weeks, five days in a week. The assessment will be done on day one of the treatment and at the end of treatment that is 8th week. Student’s t-test and Chisquare tests will be applied for statistical comparison.

Joint instability causes catabolic enzyme production in chondrocytes prior to synovial cells in novel non-invasive ACL ruptured mouse model

The Anterior Cruciate Ligament (ACL)-deficient model helps to clarify the mechanism of knee osteoarthritis (OA); however, the conventional ACL injury model could have included concurrent onset factors such as direct compression stress to cartilage and subchondral bone. In this study, we established a novel Non-invasive ACL-Ruptured mouse model without concurrent injuries and elucidated the relationship between OA progression and joint instability. We induced the ACL-Rupture non-invasively in twelve-week-old C57BL/6 male mice and evaluated histological, macroscopical, and morphological analysis at 0 days. Next, we created the ACL-R, controlled abnormal tibial translation (CATT), and Sham groups. Then, the joint stability and OA pathophysiology were analyzed at 2, 4, and 8 weeks. No intra-articular injuries, except for ACL rupture, were observed in the ACL-R model. ACL-R mice increased anterior tibial displacement compared to the Sham group (P<0.001, 95% CI [-1.509 to-0.966]) and CATT group (P<0.001, 95% CI [-0.841 to-0.298]) at 8 weeks. All mice in the ACL-R group caused cartilage degeneration. The degree of cartilage degeneration in the ACL-R group was higher than in the CATT group (P=0.006) at 8 weeks. The MMP-3-positive cell rate of chondrocytes increased in the ACL-R group than CATT group from 4 weeks (P=0.043; 95% CI [-28.32 to-0.364]) while that of synovial cells increased at 8 weeks (P=0.031; 95% CI [-23.398 to-1.021]). We successfully established a Non-invasive ACL-R model without intra-articular damage. Our model revealed that chondrocytes might react to abnormal mechanical stress prior to synovial cells while the knee OA onset.

The Influence of the Menstrual Cycle and Oral Contraceptives on Knee Laxity or Anterior Cruciate Ligament Injury Risk: A Systematic Review

Women are two to four times more prone to anterior cruciate ligament (ACL) injuries than men. This raises questions about the role of the hormonal cycle in knee laxity, which may lead to increased tibial displacement and thus ACL tears. The objective was to update scientific knowledge on the influence of the menstrual cycle on knee laxity and the risk of ACL injury, with a focus on anterior tibial displacement, and on hormonal levels influenced or not by oral contraceptive use. Observational studies obtained from Pubmed, Web of Sciences and Scopus and published between 2015 and 2022 were included in this review. Studies were required to include data on menstrual cycle with/without oral contraceptives (OC) and knee laxity and/or ACL injury. A total of ten studies were selected for this systematic review. Three studies about hormone concentration and knee laxity showed an increase in estradiol during the ovulatory phase compared to the follicular phase. Of the five studies on OC, four showed a decrease in ACL laxity. Finally, four studies assessed ACL injury. The menstrual cycle appears to influence knee laxity in women. An increase in certain hormone levels was observed in the ovulatory and luteal phases when the anterior tibial translation was greater in the knee. However, based on the literature, we cannot conclude that there is a correlation between the menstrual cycle and the risk of ACL injury.

Knee Osteoarthritis Following Anterior Cruciate Ligament Reconstruction: Frequency, Contributory Elements, and Recent Interventions to Modify the Route of Degeneration.

Half of the individuals who experience an anterior cruciate ligament reconstruction (ACLR) suffer from knee osteoarthritis (OA) 12-14 years later. Elements that make a contribution to the appearance of OA following ACLR are anomalous anterior tibial displacement and anomalous tibial rotation in the course of the stance phase of walking (exhibited in 85% of operated knees). Individuals who undergo an early ACLR (5 days on average following anterior cruciate ligament [ACL] breakage) have an inferior frequency of radiographically apparent tibiofemoral OA at 32-37 years of follow-up than individuals with ACL rupture who did not experience the procedure. Nevertheless, the percentage of symptomatic OA, radiographically apparent patellofemoral OA and knee symptoms are alike in both groups. At 15 years of follow-up, 23% of knees that experienced an anatomic ACLR suffer from OA, while this percentage augments to 44% if the ACLR was non-anatomic. Knees of individuals who experience ACLR need total knee arthroplasty at an earlier age than healthy knees. Intra-articular injections of interleukin-1 receptor antagonist and corticosteroids may reduce the risk of OA after ACLR.

The Reliability of the GNRB® Knee Arthrometer in Measuring ACL Stiffness and Laxity: Implications for Clinical Use and Clinical Trial Design.

BackgroundStability of the knee is dependent on multiple factors including integrity of the anterior cruciate ligament (ACL). Greater knee joint laxity appears to negatively affect dynamic joint function and therefore reliable and valid measures of ACL stiffness and laxity are clinically valuable.PurposeThe aim of this study was to investigate the reliability of the GENOUROB, (GNRB®) knee arthrometer device in measuring both stiffness and laxity of the ACL, and to provide information on sample size calculation for future clinical trials.Study DesignCross-sectional test-retest studyMethodTwelve healthy student participants (age 24-30 years; 6 females and 6 males) completed testing on two different testing dates. Anterior tibial translation and stiffness were measured using the GNRB® device at forces of 134N and 200N. Reliability analyses were performed using intraclass correlation coefficients (ICC). SEM, MDC, and sample size calculations were also determined.ResultsAverage anterior tibial displacements of 3.63mm and 5.32mm were found for 134N and 200N of force respectively. ICC values for intra-rater, inter-rater, and test-retest reliability were similar across measures of anterior tibial translation and stiffness, ranging from .72 to .83 (95% CI: .54 to .90). The standard error of measurement (SEM) for anterior tibial stiffness ranged from 3.47 mm/N to 3.76 mm/N. Minimal detectable change (MDC) for test-retest anterior tibial stiffness was 9.6 mm/N. Sample sizes for crossover and parallel design studies were determined.ConclusionACL laxity and stiffness measures were found to be reliably obtainable using the GNRB® knee arthrometer under the strict control of the individual’s alignment to the device and patellar pad forces. Reliable laxity and stiffness values may assist practitioners in clinical reasoning and the development of individualized ACL rehabilitation programs. Additionally, the sample size calculations presented may aid in future research design.Level of Evidence3

Progress on measurement of tibial posterior slope and its biomechanical relationship with posterior cruciate ligament

The most reliable and convenient measurement method of tibial posterior slope(TPS) and its biomechanical relationship with posterior cruciate ligament (PCL) are still controversial. For X-ray measurement, it is recommended to use full-length lateral X-ray of the lower extremity in quatrous section, which has advantage of highly repeatable and common in the daily diagnosis and treatment process, but it is only applicable to patients with tibial rotation within 15°. When the rotation exceeds 30°, it is difficult to identify the inner contour of platform and is no applicable. If it is only used for daily diagnosis and treatment evaluation, when tibial rotation angle is less than 15°, lateral knee X-ray also has a certain reference significance, but the accuracy could not meet requirements of higher clinical research. For CT measurement method, it could correct tibial rotation, but using the fitting point to measure tibial posterior slope on three-dimensional CT reconstruction is only applicable to knee joint without degeneration, more osteophyte affects the way of using fitting point to determine the plane of tibia with real tibia platform conformity degree, have some limitations. For measurement of MRI, it could not only correct tibial rotation, but also minimize the effect of osteophytes by using tibial anatomical axis as the reference axis, which is a good measurement method. For the biomechanical relationship between tibial posterior slope and tibial posterior slope, increased tibial posterior slope indirectly alleviates tension of PCL through tibial anterior displacement or directly reduces load on posterior cruciate ligament in tibial osteotomies, suggesting a protective mechanism for tibial posterior slope;in total knee arthroplasty with cruciate ligament preserved, the size of tibial posterior slope will affect roll back mechanism of femur. When affected knee with PCL injury, it should be avoid to release then aggravate injury, and the stress could be alleviated by increasing tibial posterior slope appropriately. There has been no unified conclusion on the range of tibial posterior slope that is most beneficial to PCL. The natural tibial posterior slope is between 7 ° and 10°, which is considered to be the most beneficial to protection of PCL, but further studies are needed according to the differences in patients' bone status, surgical methods and so on.

The Hybrid Transtibial Technique for Femoral Tunnel Drilling in Anterior Cruciate Ligament Reconstruction: A Finite Element Analysis Model of Graft Bending Angles and Peak Graft Stresses in Comparison With Transtibial and Anteromedial Portal Techniques.

The purpose of this finite element analysis was to compare femoral tunnel length; anterior cruciate ligament reconstruction graft bending angle; and peak graft stress, contact force, and contact area created by the transtibial, anteromedial portal (AMP), and hybrid transtibial techniques. Finite element analysis modeling was used to examine anterior cruciate ligament reconstruction models based on transtibial, AMP, and hybrid transtibial femoral tunnel drilling techniques. An evaluation of femoral tunnel length, graft bending angle, peak graft stress, contact force, and contact area was done in comparison of these techniques. The femoral tunnel created with the hybrid transtibial technique was 45.3 mm, which was 13.3% longer than that achieved with the AMP technique but 15.2% shorter than that with the transtibial technique. The femoral graft bending angle with the hybrid transtibial technique (105°) was less acute than that with the AMP technique (102°), but more acute than that with the transtibial technique (109°). At 11° knee flexion, the hybrid transtibial technique had 22% less femoral contact force, 21% less tibial contact force, 21% less graft tension than the AMP technique. Yet, the hybrid transtibial technique had 41% greater femoral contact force, 39% greater tibial contact force, 33% greater graft tension, and 6% greater graft von Mises stress than the transtibial technique. A similar trend was found for the anterior knee drawer test. At both 6-mm anterior tibial displacement and 11° knee flexion, the hybrid transtibial and AMP techniques had at least 51% more femoral contact area than the transtibial technique. This finite element analysis highlights that the hybrid transtibial technique is a true hybrid between the AMP and transtibial techniques for femoral tunnel drilling regarding femoral tunnel length, graft bending angle, and peak graft stress.

Walking in the Absence of Anterior Cruciate Ligament: The Role of the Quadriceps and Hamstrings

The actual need for surgical reconstruction of an injured anterior cruciate ligament (ACL) is still a matter of debate. The aim of this study was to quantify and analyze the knee kinematics and the ligament force redistribution resulting from the ACL sacrifice and the consequent effects of changing the quadriceps and hamstring activity during walking. A three-dimensional musculoskeletal model was used to simulate the behavior of the knee joint during the gait cycle, in different testing conditions: an ACL-deficient knee, an ACL-deficient knee with hamstrings inactivated and an ACL-deficient knee with quadriceps inactivated. Our results showed that in the ACL-deficient knee, the medial collateral ligament (MCL) was the main passive stabilizer of the anterior translation of the tibia. Furthermore, the compensation effects produced by the hamstrings and quadriceps in the ACL-deficient knee during walking were quantified and analyzed. In the case of ACL sacrifice, reducing the quadriceps activity would allow for relieving all ligaments in general, except for the posterior cruciate ligament, which required more consistent recruitment in the support phase. Meanwhile, hamstring activity was crucial not only to compensate for the absence of ACL in limiting the anterior tibial displacement but also to reduce the risk of MCL injury.

Magnetic Resonance Imaging (MRI) Based Diagnosis of Anterior Cruciate Ligament (ACL) TEARS in Patients with Internal Derangements of Knee

Objective: To assess the role of magnetic resonance imaging (MRI) in diagnosing anterior cruciate ligament (ACL) tears in patients with knee internal derangements.&#x0D; Study Design: Prospective longitudinal study.&#x0D; Place and Duration of Study: Department of Radiology, Combined Military Hospital, Kharian Pakistan, from Sep 2019 Aug 2020.&#x0D; Methodology: 40 patients of any age and gender were part of the study with painful or unstable knee joints. A clinical examination was performed after recording demographic data. In addition, MRI was performed, and primary and secondary signs were noted for each case.&#x0D; Results: The range of patients was 15 to 63, with a mean age of 36.3 ± 12.62 years. Most of the patients were male (n=29; 72.5%), whereas only 11 (27.5%) were females. In total, 27 (67.5%) complete and 13 (32.5%) partial Anterior cruciate ligament (ACL) tears were present. Blumensaat’s angle&gt; 15 degree was present in 10 (37.03%) complete tear cases and 2 (15.38 %) partial tear cases. Anterior tibial displacement was evident in 4 (14.81%) complete tear cases and 3 (23.07 %) partial tear cases. Posterior cruciate line (PCL) angle was apparent in 21 (77.77%) complete tear cases and 12 (92.30 %) partial tear cases.&#x0D; Conclusion: The use of MRI is advocated for diagnosing Anterior cruciate ligament (ACL) tears in patients with knee internal derangements.

Menstrual Cycle Changes Joint Laxity in Females-Differences between Eumenorrhea and Oligomenorrhea.

The purpose of this study was to investigate the changes in anterior knee laxity (AKL), stiffness, general joint laxity (GJL), and genu recurvatum (GR) during the menstrual cycle in female non-athletes and female athletes with normal and irregular menstrual cycles. Participants were 19 female non-athletes (eumenorrhea, n = 11; oligomenorrhea, n = 8) and 15 female athletes (eumenorrhea, n = 8; oligomenorrhea, n = 7). AKL was measured as the amount of anterior tibial displacement at 67 N–133 N. Stiffness was calculated as change in (Δ)force/Δ anterior displacement. The Beighton method was used to evaluate the GJL. The GR was measured as the maximum angle of passive knee joint extension. AKL, stiffness, GJL, and GR were measured twice in four phases during the menstrual cycle. Stiffness was significantly higher in oligomenorrhea groups than in eumenorrhea groups, although no significant differences between menstrual cycle phases were evident in female non-athletes. GR was significantly higher in the late follicular, ovulation, and luteal phases than in the early follicular phase, although no significant differences between groups were seen in female athletes. Estradiol may affect the stiffness of the periarticular muscles in the knee, suggesting that GR in female athletes may change during the menstrual cycle.

Pivot shift and Lachman test simulation-based exploration in juvenile populations for accurately predicting anterior tibial translation

Advancements in technology and finite element software have made it possible to develop simulation-based exploration of subject-specific tibiofemoral joint kinematics. In this study, the goal was to develop baseline knee models that accurately predict anterior tibial displacement when undergoing a Lachman and pivot shift test. A total of 22 subject-specific adolescent tibiofemoral joint finite element representations were developed using FEBio. The models were subject to loading conditions established in the literature to simulate the two clinical tests. Anterior tibial translations that were measured through clinical, historical controls were used to validate the proposed models. A 95% confidence interval showed that the simulated Lachman and pivot shift tests of the juvenile knee models were not statistically different from the historical controls and were in accordance with the anterior tibial translations that were measured experimentally. Clinically, simulations are important in advancing the field of knee finite element modeling, particularly in pediatric applications where the surgeon must balance restoring full function in a patient who is skeletally immature and where the growth plate is vulnerable. The methodologies created in developing these foundational models can be utilized to build more anatomically complex finite element representations that can both predict ligament stresses in response to dynamic activities and analyze the effects of different insertion sites.

In-vivo tibiofemoral kinematics of the normal knee during closed and open kinetic chain exercises: A comparative study of box squat and seated knee extension

A rehabilitation program after anterior cruciate ligament reconstruction is of great importance to obtain a satisfactory prognosis after surgery. However, there is still an onging debate over whether closed kinetic chain or open kinetic chain exercises should be chosen. Our study was designed to compare the in vivo tibiofemoral kinematics during closed kinetic chain and open kinetic chain exercises.Eighteen healthy volunteers were asked to perform box squat and unloaded/10 kg-loaded seated knee extension. In vivo 3-dimensional analysis of tibiofemoral kinematics of different motions were determined using a dual fluoroscopic imaging system.The study found significantly more tibial anterior displacement during loaded seated knee extension than during unloaded seated knee extension from 25°–50° of knee flexion (p ≤ 0.031). The knees exhibited significantly more internal tibial rotation and lateral tibial translation during the box squat than both seated knee extensions during mid-flexion. In addition, the knees showed less internal-external (IE) range of motion (ROM) from 20°– 75° of flexion (p < 0.001) and medial-lateral (ML) ROM from 75° to full extension (p ≤ 0.006) during box squat than both extensions. This knowledge may help optimize rehabilitation plans for patients post ACL reconstruction.

Experience in diagnosis and treatment of KD- ⅢM dislocation of knee joint

To explore the effectiveness of one-stage posterior medial corner (PMC) repair or reconstruction combined with anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) reconstruction in treating KD-ⅢM dislocation. The clinical data of 15 patients with knee KD-ⅢM dislocation who met the selection criteria between January 2016 and July 2019 were retrospectively analyzed. There were 9 males and 6 females, aged 22-61 years (mean, 40.3 years). Injuries were caused by violence of flexion, valgus, and external rotation, including 10 cases of traffic accident injuries, 3 cases of crush injuries, 1 case of winch injury, and 1 case of explosion injury. The time from injury to operation ranged from 3 days to 6 months, with an average of 18.5 days. PMC repair combined with PCL+ACL reconstruction was performed in 10 cases in acute stage (within 3 weeks after injury), including 3 cases of irreducible dislocation. PMC+PCL+ACL reconstruction was performed in 5 cases with chronic dislocation. Before operation and at last follow-up, the knee joint function was evaluated by Lysholm score and International Knee Documentation Committee (IKDC) 2000 score. KT-3000 was used to evaluate the forward stability of the knee (calculated the difference of tibial anterior displacement of both knees), the X-ray films of the stress position of the knee joint was used to evaluate the valgus of the knee (calculated the difference of medial joint space width of both knees) and the backward stability (calculated the difference of tibial posterior displacement of both knees), and the internal and external rotation stability was evaluated by knee flexion 30° tibial external rotation and knee flexion 90° tibial internal rotation tests (calculated the difference of tibial internal rotation and the difference of tibial external rotation of both knees). The operation time was 120-240 minutes, with an average of 186.5 minutes. Patients were followed up 24-48 months, with an average of 27.4 months. There was no complication such as infection, deep vein thrombosis, vascular injury, or heterotopic ossification. At last follow-up, the Lysholm score, IKDC2000 score, the difference of tibial anterior displacement of both knees, the difference of medial joint space width of both knees, the difference of tibial posterior displacement of both knees, the difference of tibial internal rotation and the difference of tibial external rotation of both knees significantly improved when compared with preoperative ones ( P<0.05). According to the IKDC2000 valgus stability grading standard, there were 3 cases of grade C and 12 cases of grade D before operation, and 10 cases of grade A and 5 cases of grade B at last follow-up, which was significantly improved when compared with that before operation ( Z=-4.930, P=0.000). At last follow-up, the pivot shift tests of 15 patients were negative. The anterior and posterior drawer tests of 10 patients were negative, 5 patients had mild instability, both the anterior and posterior drawer tests were positive. KD-ⅢM dislocation of the knee joint can lead to the posterior medial and anterior instability. Acute dislocation combined with "dimple sign" requires surgical reduction as soon as possible to repair PMC and reconstruct PCL and ACL. In chronic patients, PMC is difficult to repair, it is recommended to reconstruct PMC, PCL, and ACL at one stage to improve knee joint stability. The early and middle effectiveness are satisfactory.

Correlation among Knee Muscle Strength and Self-Reported Outcomes Score, Anterior Tibial Displacement, and Time Post-Injury in Non-Coper Anterior Cruciate Ligament Deficient Patients: A Cross-Sectional Study.

Little attention has been paid to knee muscle strength after ACL rupture and its effect on prognostic outcomes and treatment decisions. We studied hamstrings (H) and quadriceps (Q) strength correlation with a patient-reported outcome measures score (International Knee Documentation Committee, IKDC), anterior tibial translation (ATT), and time post-injury in 194 anterior cruciate ligament deficient patients (ACLD) who required surgery after a failed rehabilitation program (non-copers). The correlation between knee muscle strength and ATT was also studied in 53 non-injured controls. ACLD patients showed decreased knee muscle strength of both the injured and non-injured limbs. The median (interquartile range) values of the H/Q ratio were 0.61 (0.52–0.81) for patients’ injured side and 0.65 (0.57–0.8) for the non-injured side (p = 0.010). The median H/Q ratio for the controls was 0.52 (0.45–0.66) on both knees (p < 0.001, compared with the non-injured side of patients). The H/Q, ATT, and time post-injury were not significantly correlated with the IKDC score. ATT was significantly correlated with the H/Q of the injured and non-injured knees of patients, but not in the knees of the controls. Quadriceps strength and H/Q ratio were significantly correlated with ATT for both limbs of the patients. IKDC score correlated significantly with the quadriceps and hamstrings strengths of the injured limb but not with the H/Q ratio, ATT or time passed after injury.