Incidence Of Anterior Cruciate Ligament Injuries Research Articles

Gender Differences in Neuromuscular Control during the Preparation Phase of Single-Leg Landing Task in Badminton.

Studies on the biomechanical mechanisms of an anterior cruciate ligament (ACL) injury have been extensively studied, but studies on the neuromuscular control-related risk factors for an ACL injury in specific maneuvers have not been reported for badminton players. Controlled laboratory study. Sixteen badminton players (8 male, 8 female) performed a single-leg badminton ball landing task, and lower limb muscle activity, kinematic data, and ground reaction force were measured during this procedure using marker-based movement analysis, force plates, and electromyography (EMG). Gender differences in the lower limb kinematic data, mean values of normalized lower limb muscle activation (MVC%), and co-contraction values during the landing preparation phase (100 ms before initial contact) were analyzed using MANOVA. In the badminton landing task, the knee valgus angle was greater in females than in males (6.27 ± 2.75 vs. 1.72 ± 3.20) in the pre-landing preparation position. Compared to male badminton players, females exhibited greater gluteus maximus (44.92 ± 18.00 vs. 20.34 ± 11.64), rectus femoris (41.56 ± 9.84 vs. 26.14 ± 10.46), and medial gastrocnemius (37.39 ± 17.31 vs. 19.11 ± 11.17) lateral gastrocnemius (36.86 ± 17.82 vs. 13.59 ± 2.71) muscle activity (MVC%). Female badminton players exhibit neuromuscular control strategies that may be inadequate for ACL protection and may be a potential risk factor for a high incidence of ACL injury In the future, when devising injury prevention plans for female badminton players, optimizing neuromuscular control during the pre-landing phase can be targeted.

A new etiological cause for anterior cruciate ligament injury: E-Scooter.

The usage of electric scooters has been popular because it is a cheap and fast transportation method. Its use has increased in recent years because public transportation is less preferred during the covid-19 pandemic and in parallel, the publications reporting e-scooter accidents are increasing. There is no article examining the relationship between e-scooter and anterior cruciate ligament (ACL) injury in current literature. We aim to examine the relationship between e-scooter accidents and ACL injury incidence. Patients over the age of 18 years who applied to our orthopedics outpatient clinic with the diagnosis of ACL injury between January 2019- June 2021 were evaluated. 80 e-scooter accidents resulting with ACL tears were reviewed. The electronic medical records of the patients were reviewed retrospectively. Information about the age, gender, trauma history of the patients, and type of trauma was obtained. Fifty-eight patients had a history of falling while stopping the scooter, and 22 patients had a history of falling after hitting something. Anterior cruciate ligament reconstruction was performed with hamstring tendon grafts in 62(77,5%) of the patients included in the study. 18 (22,5%) patients were followed up with functional physical therapy exercises because they did not want to be operated on. Various bone or soft tissue injuries while using e-scooters have been reported in the literature until now. ACL injury is also seen quite frequently after these traumas, and necessary information and warnings should be given to the users to prevent ACL injuries.

Clinical Outcomes After ACL Reconstruction in Soccer (Football, Futbol) Players: A Systematic Review and Meta-Analysis.

The risk factors for anterior cruciate ligament (ACL) tear for athletes participating in pivoting sports includes young age and female sex. A previous meta-analysis has reported a reinjury rate of 15% after ACL reconstruction (ACLR) for athletes across all sports. To the best of the authors' knowledge, this is the first systematic review and meta-analysis of available literature reporting outcomes after ACLR in soccer players. To review and aggregate soccer-specific outcomes data after ACLR found in current literature to help guide a more tailored discussion regarding expectations and prognosis for soccer players seeking operative management of ACL injuries. A comprehensive search of publications was performed using PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and SPORTDiscus databases. Inclusion criteria consisted of original studies, level of evidence 1 to 4, studies reporting clinical and patient-reported outcomes (PROs) after primary ACLR in soccer players at all follow-up length. The primary outcomes of interest were graft failure/reoperation rates, ACL injury in contralateral knee, return to soccer time, and PROs. Level 4. Search of literature yielded 32 studies for inclusion that involved 3112 soccer players after ACLR. The overall graft failure/reoperation rate ranged between 3.0% and 24.8% (mean follow-up range, 2.3-10 years) and the combined ACL graft failure and contralateral ACL injury rate after initial ACLR was 1.0% to 16.7% (mean follow-up range, 3-10 years); a subgroup analysis for female and male players revealed a secondary ACL injury incidence rate of 27%, 95% CI (22%, 32%) and 10%, 95% CI (6%, 15%), respectively. Soccer players were able to return to play between 6.1 and 11.1 months and the majority of PROs showed favorable scores at medium-term follow-up. Soccer players experience high ACL injury rates after primary ACLR and demonstrated similar reinjury rates as found in previous literature of athletes who participate in high-demand pivoting sports.

The Effect of a Knee Brace on Muscle Forces during Single-Leg Landings at Two Heights

Single-leg landing is one of the maneuvers that has been linked to non-contact anterior cruciate ligament (ACL) injuries, and wearing knee braces has been shown to reduce ACL injury incidence. The purpose of this study was to determine whether wearing a knee brace has an effect on muscle force during single-leg landings at two heights through musculoskeletal simulation. Eleven healthy male participants, some braced and some non-braced were recruited to perform single-leg landings at 30 cm and 45 cm. We recorded the trajectories and ground reaction forces (GRF) using an eight-camera motion capture system and a force platform. The captured data were imported into the generic musculoskeletal model (Gait2392) in OpenSim. Static optimization was used to calculate the muscle forces. The gluteus minimus, rectus femoris, vastus medialis, vastus lateralis, vastus medialis medial gastrocnemius, lateral gartrocnemius, and soleus muscle forces were all statistically significant different between the braced and non-braced participants. Simultaneously, increasing the landing height significantly affected the gluteus maximums, vastus medialis, and vastus intermedia muscle forces. Our findings imply that wearing a knee brace may alter muscle forces during single-leg landings, preventing ACL injuries. Additionally, research demonstrates that people should avoid landing from heights due to the increased risk of knee injuries.

The incidence rate of ACL injuries and ankle sprains in basketball players: A systematic review and meta-analysis.

To quantify the incidence rate of anterior cruciate ligament (ACL) injuries and ankle sprains according to player sex, playing level, and exposure setting (training vs. games) in basketball players. PubMed, MEDLINE, Google Scholar, and ScienceDirect were searched. Only studies reporting the number of ACL injuries and/or ankle sprains alongside the number of athlete-exposures (training sessions and/or games) in basketball players were included. Thirty studies (17 reporting ACL injuries and 16 reporting ankle sprains) were included in the meta-analysis. Higher (p < 0.05) ACL injury incidence rates per 1000 athlete-exposures were recorded in females (female: 0.20 95% confidence intervals [0.16-0.25]; male: 0.07 [0.05-0.08]; female-to-male ratio: 3.33 [3.10-3.57]), in players competing at higher playing levels (amateur: 0.06 [0.04-0.09]; intermediate: 0.16 [0.13-0.20]; elite: 0.25 [0.14-0.64]), and in games (games: female, 0.27 [0.21-0.32]; male, 0.06 [0.03-0.08]; training: female, 0.03 [0.02-0.05]; male: 0.01 [0.00-0.02]; game-to-training ratio: 7.90 [4.88-12.91]). Higher (p < 0.05) ankle sprain incidence rates per 1000 athlete-exposures were observed in males (female: 0.82 [0.61-1.03]; male: 0.90 [0.61-1.19]; female-to-male ratio: 0.91 [0.83-0.99]), in players competing at higher playing levels (amateur: 0.54 [0.51-0.57]; intermediate: 1.12 [1.00-1.24]; elite: 1.87 [1.29-2.46]), and in games (games: 2.51 [1.85-3.16]; training: 0.80 [0.52-0.80]; game-to-training ratio: 2.77 [2.35-3.26]). According to player sex, ACL injury incidence rate is higher in females, while ankle sprain incidence rate is greater in males. ACL injury and ankle sprain incidence rates are greater in players competing at higher playing levels and during games compared to training.

The incidence of anterior cruciate ligament injury in youth and male soccer athletes: an evaluation of 17,108 players over two consecutive seasons with an age-based sub-analysis.

To evaluate the incidence of anterior cruciate ligament (ACL) injuries in male athletes from professional soccer clubs over two consecutive seasons (2018-2019) with a sub-analysis based on age category: under-13 (U-13), under-15 (U-15), under-17 (U-17), and under-20 (U-20) years. A total of 17,108 young male soccer players were retrospectively reviewed from sixty-three professional clubs in the four highest Brazilian soccer divisions. Data regarding the number of athletes and the number of ACL injuries confirmed by magnetic resonance imaging (MRI) exams in the 2018 and 2019 seasons were collected. Incidence of ACL injury were compared by season, age category (under-13; under-15; under 17; and under-20), demographic region, and club division. Clubs from all regions of Brazil participated in the study. A total of 336 primary ACL injuries were diagnosed over the two seasons (8,167 athletes during the 2018 season and 8,941 athletes during the 2019 season) among all athletes, which corresponds to 2% of the included athletes. There were 11 cases (0.3%) in the under-13, 53 cases (1.3%) in the under-15, 107 cases (2.5%) in the under-17, and 165 cases (3.8%) in the under-20 age category. There was a higher incidence of ACL injury in the older age groups (p < 0.001). A total of 336 ACL injuries were identified in 17,108 youth soccer players from 63 professional clubs with an overall incidence of 2% over 2 seasons of competition. ACL injury rate ranged from 0.3% to 3.8% and was higher in the older and more competitive club divisions. IV.

Higher Adherence to Anterior Cruciate Ligament Injury Prevention Programs Is Associated With Lower Injury Rates: A Meta-Analysis and Meta-Regression.

Background: Athletes who participate in sports that involve cutting and pivoting movements are particularly susceptible to anterior cruciate ligament (ACL) injury. Preventing this injury is the best way to combat its health consequences and costs. There may be a dose-response relationship between adherence and injury reduction. Purpose: We sought to examine whether athletes' adherence to injury prevention programs (IPPs) is associated with reductions in ACL and lower extremity (LE) injuries. Methods: We conducted a systematic review of the PubMed, EMBASE, and Cochrane Library databases, searching for studies published between 2011 and 2021. Studies were included if they reported on the use of an ACL IPP compared with a control group and recorded the rate of injuries to calculate a rate ratio, as well as adherence to the program as a percentage of sessions performed. For the meta-analysis, the rate ratios were pooled using the DerSimonian-Laird random-effects model. Results: For the 15 studies included (11 randomized controlled trials and 4 cohort studies), the random-effects model grouped athletes' adherence to an IPP as high (76% or more of the sessions), moderate (51%-75% of the sessions), and low (50% or fewer of the sessions). We found that athletes with the highest level of IPP adherence had a significantly lower incidence of ACL injury. The rate ratios for moderate and low adherence did not demonstrate a reduced incidence of ACL injury. Injury prevention program participation was also associated with a decrease in LE injury rates. Conclusion: This systematic review and meta-analysis found that athletes with high adherence to IPPs had reduced rates of ACL and LE injuries. Our findings suggest that educating coaches and athletes on the dose-dependent benefits of IPPs may promote the routine incorporation of these programs into warm-up sessions to decrease the risk of ACL and LE injuries.

Exploring pre-impact landing kinematics associated with increase and decrease in the anterior cruciate ligament injury risk

This study aimed to explore the single-legged landing kinematics that could lead to increase or decrease in the risk of anterior cruciate ligament (ACL) injury. Immediate pre-impact kinematics at the single-legged landing from 33 healthy young female handball players were evaluated. Thereafter, two-year follow-up for ACL injury incidence was conducted, in which six new ACL injuries in non-dominant leg were registered. The evaluation of pre-impact kinematics across participants was performed first by the principal component analysis to decompose them into the kinematic components (KCs), and then by the linear discrimination analysis (LDA) for a set of KC-scores to obtain important KCs for discriminating injured and non-injured legs. The result of LDA showed that the combination of second major KC (knee flexion/extension angle and angular velocity) and some minor KCs such as torso medial/lateral leaning accurately discriminated the injured and non-injured legs with the error rate of 12.5%. To examine the mechanisms of this discriminative ability, we generated hypothetical pre-impact kinematics in the subspaces spanned by eigenvectors of multiple KCs, and examined relationships between pre-impact kinematics and the corresponding knee valgus torque predicted by the motion-equation-based model. The result showed that the second major KC and the minor KCs representing torso medial/lateral leaning and/or hip adduction/abduction angle, which contributed in LDA to discriminating injured legs, also significantly affected the frontal-plane knee loading patterns. These findings suggested that KC-based postural characterization of the pre-impact landing kinematics and the motion-equation-based knee stress quantification possibly explain the future ACL injury risks of female athletes.

ACL Research Retreat IX Summary Statement: The Pediatric Athlete, March 17-19, 2022; High Point, North Carolina.

ACL Research Retreat IX Summary Statement: The Pediatric Athlete, March 17-19, 2022; High Point, North Carolina.

Return-to-Sport Criteria After Anterior Cruciate Ligament Reconstruction Fail to Identify the Risk of Second Anterior Cruciate Ligament Injury.

The incidence of second anterior cruciate ligament (ACL) injury after ACL reconstruction (ACLR) is high in young, active populations. Failure to successfully meet return-to-sport (RTS) criteria may identify adult athletes at risk of future injury; however, these studies have yet to assess skeletally mature adolescent athletes. To determine if failure to meet RTS criteria would identify adolescent and young adult athletes at risk for future ACL injury after ACLR and RTS. The tested hypothesis was that the risk of a second ACL injury after RTS would be lower in participants who met all RTS criteria compared with those who failed to meet all criteria before RTS. Prospective case-cohort (prognosis) study. Laboratory. A total of 159 individuals (age = 17.2 ± 2.6 years, males = 47, females = 112). Participants completed an RTS assessment (quadriceps strength, functional hop tests) and the International Knee Documentation Committee patient survey (0 to 100 scale) after ACLR and were then tracked for occurrence of a second ACL tear. Athletes were classified into groups that passed all 6 RTS tests at a criterion level of 90% (or 90 of 100) limb symmetry and were compared with those who failed to meet all criteria. Crude odds ratios and 95% CIs were calculated to determine if passing all 6 RTS measures resulted in a reduced risk of second ACL injury in the first 24 months after RTS. Thirty-five (22%) of the participants sustained a second ACL injury. At the time of RTS, 26% achieved ≥90 on all tests, and the remaining athletes scored less than 90 on at least 1 of the 6 assessments. The second ACL injury incidence did not differ between those who passed all RTS criteria (28.6%) and those who failed at least 1 criterion (19.7%, P = .23). Subgroup analysis by graft type also indicated no differences between groups (P > .05). Current RTS criteria at a 90% threshold did not identify active skeletally mature adolescent and young adult athletes at high risk for second ACL injury.

High revision arthroscopy rate after ACL reconstruction in men's professional team sports.

The study analysed unique data on anterior cruciate ligament (ACL) injuries among German professional male team sports over five consecutive seasons with the aim of improving medical outcomes in the future. Sport-specific differences in injury occurrence, concomitant injuries, timing of ACL reconstruction, graft type selection and short-term complications were examined. This retrospective study analysed trauma insurance data on all complete ACL tears from players with at least one competitive match appearance in the two highest divisions of German male basketball, ice hockey, football and handball. Each complete ACL tear registered by clubs or physicians between the 2014/15 and 2018/19 seasons with the German statutory accidental insurance for professional athletes (VBG) as part of occupational accident reporting was included. In total, 189 out of 7517 players (2.5%) sustained an ACL injury, mainly in handball (n = 82; 43.4%) and football (n = 72; 38.1%) followed by ice hockey (n = 20; 10.6%) and basketball (n = 15; 7.9%).Seventeen players (9.0%) also sustained a second ACL injury. Thus, 206 ACL injuries were included in the analysis. The overall match incidence of ACL injuries was 0.5 per 1000h and was highest in handballs (1.1 injuries per 1000h). A total of 70.4% of ACL injuries involved concomitant injury to other knee structures, and 29.6% were isolated ACL injuries. The highest rate of isolated ACL injuries was seen in ice hockey (42.9%). All ACL injuries, except for one career-ending injury, required surgery. In the four analysed team sports, hamstring tendons (71.4%) were the most commonly used grafts for ACL reconstruction; football had the highest percentage of alternative grafts (48.7%). During rehabilitation, 22.9% of all surgically treated ACL injuries (n = 205) required at least two surgical interventions, and 15.6% required revision arthroscopy. The main cause of revision arthroscopy (n = 32; 50.0%) was range-of-motion deficit due to arthrofibrosis or cyclops formation. The present study shows an overall high rate of revision arthroscopy after ACLR (15.6%), which should encourage surgeons and therapists to evaluate their treatment and rehabilitation strategies in this specific subpopulation. Hamstring tendon grafts are most commonly used for ACL reconstruction but have the highest revision and infection rates. Handball shows the highest ACL injury risk of the four evaluated professional team sports. Concomitant injuries occur in the majority of cases, with the highest share of isolated ACL injuries occurring in ice hockey. Level III.

Increased Risk of ACL Injury for Female but Not Male Soccer Players on Artificial Turf Versus Natural Grass: A Systematic Review and Meta-Analysis.

Background:Both natural grass (NG) and artificial turf (AT) are popular playing surfaces for soccer. Biomechanical studies have found increased frictional forces on AT that may lead to anterior cruciate ligament (ACL) injury. The increased risk of ACL injury during soccer in female participants may amplify this effect.Purpose:To systematically review the literature for studies comparing ACL injury risk in soccer players on AT versus NG and to specifically determine whether there were differences in injury risk in male versus female players when considering the playing surface.Study Design:Systematic review; Level of evidence, 3.Methods:A systematic review was performed using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Three databases were searched for studies with evidence level 1 to 3 that compared the incidence of ACL injuries on AT versus NG in soccer players. Data recorded included study characteristics, sex, competition level, exposure setting (games or practices), turf type, and ACL injury information. Study methodological quality was analyzed using the methodological index for non-randomized studies (MINORS) score, and incidence rate ratios (IRRs) were calculated.Results:Included were 7 articles (3 studying professional soccer, 3 collegiate soccer, 1 youth-level soccer; 4 male cohorts, 2 female cohorts, and 1 male and female cohort; mean MINORS score, 20 ± 0.8). Pooled ACL injury IRRs demonstrated no significant differences in overall ACL injury risk when playing soccer on AT compared with NG (IRR = 0.57 [95% CI, 0.21-1.53]; P = .31). A significantly increased risk of ACL injury in games played on AT compared with NG was detected for female (IRR = 1.18 [95% CI, 1.05-1.31]; P = .004) but not for male players (IRR = 1.18 [95% CI, 0.97-1.42]; P = .09). Subgroup analyses showed no significant differences in injury risk for games (IRR = 1.07 [95% CI, 0.97-1.18]; P = .20) or practices (IRR = 0.21 [95% CI, 0.04-1.23]; P = .09).Conclusion:Findings indicated that female soccer players had a significantly higher risk of ACL injury when playing games on AT versus NG, whereas no significant difference was seen in male players. No differences were found for the combined male/female cohort or for soccer games or training sessions played on AT compared with NG.

Poster 250: Increased Risk of Anterior Cruciate Ligament Injuries for Female but Not Male Soccer Players on Artificial Turf Versus Natural Grass: A Systematic Review and Meta-Analysis

Objectives:Both natural grass (NG) and artificial turf (AT) are popular playing surfaces for soccer. Biomechanical studies have found increased frictional forces on artificial turf that may lead to anterior cruciate ligament (ACL) injury. Few studies have examined the differences between ACL injury risk in male and female soccer athletes playing on AT versus NG. Given the higher risk for female ACL injury in sports, and soccer in particular, it is important to define whether AT may compound this injury risk. The purpose of this investigation was to systematically review the literature for studies comparing ACL injury risk on AT versus NG in soccer, and to specifically determine if there were differences in injury risk in males versus females when considering the playing surface.Methods:A systematic review was pre-registered on PROSPERO and performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed, SCOPUS, and Cochrane Central Register of Controlled Trials were searched for Level I-III studies that compared the incidence of ACL injuries on AT versus NG in soccer players. Data recorded included study demographics, sex, competition level, exposure setting (games or practices), turf type, and ACL injury information. Study methodological quality was analyzed using the Methodological Index for Non-Randomized Studies (MINORS) score. Incidence rate ratios (IRRs) were calculated by dividing the incidence of ACL injury on AT over NG, where IRRs < 1 indicate a lower incidence of ACL injuries on AT compared to NG, and IRRs > 1 signify a higher incidence of ACL injuries on AT compared to NG. A Mantel-Haenszel random effects model was used for meta-analyses of IRRs, and forest plots were generated for the pooled IRR for ACL injuries in game and training settings. Additionally, sub-analyses based on athlete sex were conducted for IRRs of ACL injuries in games. A p-value of less than 0.05 was set as significant.Results:Seven articles (four male, two female, one male and female cohort; mean MINORS score 20 + 0.8) were included and analyzed (Figure 1). There were two studies that investigated ACL injuries in a female only cohort, four studies that used a male only cohort, and one study that included both males and females (Table 1). Levels of play included professional (n = 3 studies), college (n = 3 studies), and youth (n = 1 studies). Pooled ACL injury IRRs demonstrated no significant differences in overall ACL injury risk when playing soccer on AT compared to NG (IRR = 0.61 [0.23-1.60], p = 0.31; Figure 2). A significantly increased risk of ACL injury in games played on AT compared to NG was detected for females (IRR = 1.18 [1.05-1.31], p = 0.004) but not for males (IRR = 1.18 [0.97- 1.42], p = 0.09; Figure 3). Subgroup analyses showed no significant differences in injury risk for games (IRR = 1.07 [0.97- 1.18], p = 0.20) or practices (IRR = 0.21 [0.04-1.23], p = 0.09; Figure 2). A total of 3,023 ACL injuries occurred on NG and 526 ACL injuries happened on AT, and the majority of soccer exposures in each study was on NG (range: 50.33% - 85.74%).Conclusions:.This investigation found that females had a significantly higher risk of ACL injury when playing games on AT versus NG, whereas no significant difference was seen in males. No differences were found for the combined male/female population nor soccer games or training sessions played on AT compared to NG.Figure 1.Flow diagram summarizing the literature search, screening, and review.Figure 2.Forest plot of the pooled incidence rate ratios {IRRs) for anterior cruciate ligament (ACL) injury on artificial turf (AT) versus natural grass (NG) in soccer players with sub-analysis by exposure setting (game versus training). CI - Confidence IntervalFigure 3.Forest plot of the sub-analysis based on sex (male or female) of pooled incidence rate ratios (IRRs) for anterior cruciate ligament (ACL) injury in soccer games played on artificial turf (AT) versus natural pass (NG). CI - Confidence IntervalTable 1.Summary of study demographics for included articles. MINORS - Methodological Index for Non-Randomized Studies; BJSM - British Journal of Sports Medicine, AJSM - American Journal of Sports Medicine; KSSTA - Knee Surgery, Sports Traumatology, Arthroscopy; OJSM - Orthopaedic Journal of Sports Medicine; SJMSS -Scandinavian Journal of Medicine & Science in Sports; NS - Not Specified

Brain Neuroplasticity Effects on the Occurrence of Anterior Cruciate Ligament Injury and the Effect of this Injury on Brain Function and Structure: A Systematic Review

Objective: The present study aimed to investigate the effect of brain neuroplasticity on the incidence of anterior cruciate ligament (ACL) injury and on brain function and structure before and after ligament reconstruction and after a period of rehabilitation exercises. Materials &amp; Methods: In this review study, a search was conducted in PubMed, Scopus, Web of Science, Google Scholar, ScienceDirect, MedLine, Pedro, CINAHL, SPORTDiscus, and Cochrane Databases as well as national databases on related studies published from 1970 to 2021 using keywords in Persian and English related to the research topic. Results: The initial search yielded 65 articles. Based on the inclusion and exclusion criteria, 24 articles were selected for review of which 5 articles prospectively examined the effect of brain neuroplasticity on the incidence of ACL injury. Their results showed that the brains of people with ACL injury was different from the uninjured people, especially in the motor-sensory part of the cerebral cortex and cerebellum, which caused errors during movement planning of these persons. Ten articles examined the effect of ACL injury before reconstruction on brain function and structure and reported that changes occur in the level of motor-sensory cortex of the brain at least two weeks after the injury; after one year, these structural and functional changes were widely increased in injured people compared to healthy people. These studies also showed that the ligament dysfunction and the damage to mechanical receptors cause the reorganization of the central nervous system. In injured people, the control activity of motor-visual areas and their need for visual feedback have increased. Seven articles examined these changes after ligament reconstruction and showed that the brain neuroplasticity or functional and structural changes resulting from the injury not only did not return to normal conditions, but also increased after a while despite the reconstruction. Two articles examined these changes after a period of rehabilitation exercises and showed that functional and Conclusion: The changes in the brain after ACL injury not only persist after ligament reconstruction, but also increase after reconstruction. The common rehabilitation exercises whose main focus is not on eliminating these functional and structural changes in the brain cannot overdrive this negative neuroplasticity after injury which is one of the important causes of secondary injury and subsequent complications. In developing exercises to prevent ACL injury and for rehabilitation, it is better to use the new principles of motor learning and exercises related to visual feedback along with conventional exercises to overdrive negative neuroplasticity created in the brain and create positive neuroplasticity to support ACL.

Is there a biomechanical “Rule of Thirds” after ACL injury and reconstruction?

Purpose and objectiveThe purpose of this study was to analyze the biomechanical outcomes of patients with Anterior Cruciate Ligament (ACL) deficiency or insufficiency and ACL reconstruction and to determine if they follow a biomechanical “Rule of Thirds.” Background and principle resultsThe Cincinnati Group reported nearly four decades ago that approximately one-third of patients do not experience a decline in biomechanical function in the absence of an ACL, one-third adapt their biomechanics to avoid knee symptoms, and one-third of patients do not adapt biomechanically to the loss of their ACL in order to function during activities of daily living without pain, swelling and giving way episodes. Subsequently, three decades ago the San Diego Group developed the Surgical Risk Factor (SURF) algorithm, which was designed to prospectively classify the biomechanics of patients who are ACL deficient. These classification systems have also delineated patient function into three categories. Currently, especially over the last decade, a growing body of work has documented that the incidence of second ACL injuries is consistent with the division of patient function by thirds. Approximately one-third of young, active individuals who return to high intensity sports sustain a second injury to either the ipsi- or contralateral knee. Summary and major conclusionsIn this Biomechanics focused article in the Journal of Orthopedics, the authors describe differential patient outcomes with a Rule of Thirds concept, including the original study performed by our former group in Cincinnati and the SURF algorithm out of San Diego, the authors also present second ACL injury rates and how they are consistent with the Rule of Thirds, as well as the biomechanical implications for patient care.

Is the Use of Oral Contraceptive Beneficial to Female Athletes in the Prevention of Anterior Cruciate Ligament Injury?

Research has shown that women are 2 to 9 times more likely to sustain an anterior cruciate ligament (ACL) injury than men. The increased risk of ACL injuries in females can be attributed to several factors including anatomical, hormonal, biomechanical, and neuromuscular variations. Previous literature found that female hormones such as relaxin, progestin, and estrogen play a role in ligamentous laxity within the female ACL. Oral contraceptives (OC) regulate these hormones by inhibiting the spike of estrogen and progestin during the menstrual cycle. The aims of this study were to investigate the influence of female hormone concentrations on the ACL and to determine if OC can reduce the risk of ACL injuries in female athletes. We hypothesize that OC will have an effect on reducing the incidence of ACL injuries in female athletes. Articles were retrieved from Google Scholar and PubMed databases. A systematic review was conducted and ranked using the Oxford Levels of Evidence. The result revealed there are variations in the ranking of literature based on the Oxford Levels of Evidence. The evidence reveals that OC may have an inhibitory effect on relaxin receptors within the female ACL and could be recommended as a preventive measure for ACL ligamentous injury. Further research is needed to determine the causal effect of oral contraceptives on ACL prevention.

The Hamstring and ACL Injury Incidence during a Season Is Not Directly Related to Preseason Knee Strength Ratios in Elite Male Soccer Players

Background and Objectives: The aim of this study was to identify preseason isokinetic strength differences in the knee flexors and extensors and their ipsilateral/bilateral ratios and, furthermore, to compare the results among players who subsequently overcame a hamstring strain injury (HSI) or anterior cruciate ligament (ACL) rupture during the season and those who did not. Materials and Methods: A total of 134 professional soccer players underwent isokinetic strength assessment at a velocity of 60°·s−1 (knee flexors and extensors) for the dominant and non-dominant lower limb to determine preseason peak torque values and bilateral and ipsilateral strength ratios. Subsequently, the incidence of injuries during the season was recorded, and players were divided into groups according to ACL rupture injuries (n = 10), hamstring strains (n = 10), and a control group of non-injured players who were selected on a random basis (n = 20). A retrospective approach was used to analyze and compare the preseason strength characteristics and whether some variance among groups was relevant among the injured leg and non-injured leg groups. Results: The results of our study show that low-angular velocity preseason testing did not result in a player’s HSI or ACL injury during the season. The difference between the monitored groups ranged from 1.5% to 3%. The comparison showed low evidence for significant differences. Conclusions: An angular velocity of 60°·s−1 within concentric muscle contraction alone was not linked to subsequent injury of the hamstring or anterior cruciate ligament and acted as an insufficient factor of injury risk in adult professional soccer players.

Contemporary Principles for Postoperative Rehabilitation and Return to Sport for Athletes Undergoing Anterior Cruciate Ligament Reconstruction

AbstractDespite advancements in our understanding of anterior cruciate ligament (ACL) injury prevention and nonsurgical management, ACL reconstruction continues to occur at an alarming rate. Among athletic patients, individuals participating in basketball, soccer, and football have the highest incidence of ACL injury, often requiring surgical intervention. To ensure the optimal treatment strategy for return to sport and prevention of secondary graft re-tear, it is important to tailor to the specific demands of the injured athlete and apply evidence-based best practices and rehabilitation principles. The purpose of this review is to provide readers with a brief background regarding ACL injuries, a focused review of clinical outcome studies after ACL reconstruction, and an updated framework with expert-guided recommendations for postoperative rehabilitation and return to sporting activity. Currently, there is no gold standard for rehabilitation after ACL reconstruction, highlighting the need for robust studies evaluating the best modalities for athlete rehabilitation, as well as determining the efficacy of new tools for improving therapy including blood flow restriction therapy and neuromuscular electrical stimulation. Based on clinical experience, a renewed focus on objective, criteria-based milestones may maximize the ability of return to preinjury levels of athletic function.

Exercise-Based Training Strategies to Reduce the Incidence or Mitigate the Risk Factors of Anterior Cruciate Ligament Injury in Adult Football (Soccer) Players: A Systematic Review.

Anterior cruciate ligament (ACL) is one of the most concerning injuries for football players. The aim of this review is to investigate the effects of exercise-based interventions targeting at reducing ACL injury rate or mitigating risk factors of ACL injury in adult football players. Following PRISMA guidelines, a systematic search was conducted in CINAHL, Cochrane Library, PubMed, Scopus, SPORTDiscus and Web of Science. Studies assessing the effect of exercise-based interventions in ACL injury incidence or modifiable risk factors in adult football players were included. 29 studies evaluating 4502 male and 1589 female players were included (15 RCT, 8 NRCT, 6 single-arm): 14 included warm-up, 7 resistance training, 4 mixed training, 3 balance, 1 core stability and 1 technique modification interventions. 6 out of 29 studies investigated the effect of interventions on ACL injury incidence, while the remaining 23 investigated their effect on risk factors. Only 21% and 13% studies evaluating risk of injury variables reported reliability measures and/or smallest worthwhile change data. Warm-up, core stability, balance and technique modification appear effective and feasible interventions to be included in football teams. However, the use of more ecologically valid tests and individually tailored interventions targeting specific ACL injury mechanisms are required.

Incidence of anterior tibial spine fracture among skiers does not differ with age.

Injury to the anterior cruciate ligament (ACL) is common in alpine skiing in the form of either an intra-substance ACL tear or anterior tibial spine fracture (ATSF). Anterior tibial spine fractures are typically reported in children. However, several case reports describe these injuries in adults while skiing. The purpose of this study is to describe the sport specific incidence of ATSF in alpine skiing. The study was conducted over a 22-year period. Skiers who suffered an ATSF were identified and radiographs were reviewed to confirm the diagnosis. Additionally, control data from intra-substance ACL injury groups were collected. The incidence of these injuries in children, adolescents, and adults (grouped as ages 0-10, 11-16, and 17 + years old, respectively) was evaluated and the risk factors for ATSF versus ACL tear were determined. There were 1688 intra-substance ACL and 51 ATSF injuries. The incidence of intra-substance ACL injury was greater in adults (40.0 per 100,000 skier days) compared to the adolescent (15.4 per 100,000) and child (1.1 per 100,000) age groups. In contrast, the incidence of ATSF was similar in the adult (0.9 per 100,000), adolescent (1.9 per 100,000), and child (1.9 per 100,000) age groups. Loose ski boot fit was identified as a risk factor for ATSF. The incidence of ATSF in alpine skiers is similar among all age groups. However, the incidence of intra-substance ACL injuries is far greater in adult skiers compared to adolescents and children. Risk factors for ATSF relate to compliance between the foot/ankle and the ski boot. III.