Risk Of Anterior Cruciate Ligament Tear Research Articles

Comparison of Size of Posterior Tibial Slope and Medial Tibial Depth in Patients With an Isolated Meniscal Tear Requiring Surgery and Matched Uninjured Controls

Background: Meniscal injuries are extremely common. Several anatomic features of the knee, including the tibial plateau morphology, have been shown to influence knee biomechanics and the risk of ligamentous injuries. Little is known, however, how these morphological features influence the risk of isolated meniscal injuries in the anterior cruciate ligament (ACL)–intact knee. Hypothesis: There are differences in the slopes and concavity of the tibial plateau between patients with isolated meniscal tears and matched uninjured controls. Study Design: Cohort study; Level of evidence, 3. Methods: In total, 89 patients with first-instance isolated medial (n = 37) or lateral (n = 52) meniscal injuries requiring surgical treatment (mean age, 16 ± 1 years; 35% female) were matched to 89 controls with uninjured knees and no previous injuries (mean age, 16 ± 2 years; 35% female) based on age and sex. Magnetic resonance imaging scans (preoperative for injured group) were used to measure the coronal slope of the tibial plateau, posterior slope of the medial and lateral tibial plateaus, and maximum depth of the medial tibial plateau. General linear models were used to evaluate the differences in tibial plateau morphology between the knees with and without meniscal injuries, with and without adjustment for age and sex. Results: Compared with matched controls, patients with surgically treated isolated meniscal tears had a smaller lateral tibial slope (by 2.2° [medial meniscal injury] and 1.6° [lateral meniscal injury]; P < .02), a smaller medial tibial slope (by 2.3° [medial meniscal injury] and 2.4° [lateral meniscal injury]; P < .001) and a larger medial tibial depth (by 0.8 mm [medial meniscal injury] and 0.9 mm [lateral meniscal injury]; P < .001). There were no differences in coronal tibial slope between the injured and uninjured groups. There were no differences in quantified anatomic features between the isolated medial and lateral meniscal injury groups. The same trends were observed after adjusting for age and sex. Conclusion: This study suggests that patients with an isolated meniscal tear requiring surgery have a smaller posterior tibial slope and a larger medial tibial depth (more concave medial tibial plateau) than matched uninjured controls. This is contrary to what is known for ACL tears, in which a steeper posterior tibial slope and a shallower medial tibial depth have been associated with an increased risk of ACL tear.

Vertical Stenosis as a Morphological Risk Factor for Anterior Cruciate Ligament Ruptures in Children: A Magnetic Resonance Imaging–Based Comparison

Background: There are known anatomic variations that may lead to traumatic disruption of the anterior cruciate ligament (ACL) identified within adult and adolescent patients. Purpose/Hypothesis: The purpose of this study was to compare the parameters of pediatric knees diagnosed with and without an ACL injury by magnetic resonance imaging. The hypothesis was that children with ACL abnormalities would demonstrate an equivalent notch width index (NWI), but a larger notch height index (NHI), in comparison with age-matched patients without ACL abnormalities, suggesting an association with congenital morphology. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A retrospective comparison cohort study of pediatric knees was performed by evaluating those with a confirmed ACL rupture/deficiency and those with a benign diagnosis on magnetic resonance imaging. Overall, 6 osseous and cartilaginous measurements and 3 ratios (2 newly described) were determined. They were then grouped for statistical purposes by age: children aged 5 to 11 years and adolescents aged 12 to 19 years. Results: A total of 119 (49 children) consecutive patients with an ACL injury and 139 (72 children) healthy patients met inclusion criteria. The interaction between ACL status and age was significant for condylar measurements (P≤ .001), tibial spine height (P = .003), vertical space above tibial spine (P≤ .001), and NWI (P≤ .001) by 2-way analysis of variance. Although the NHI (P < 0.001) and tibial spine prominence (P = 0.039) demonstrated stenosis in the adolescent group, they did not have significant interactions with age and ACL status (P > 0.05). Regarding the transcondylar width, only the children's group had a significant difference regarding ACL status (P < .001), and the mean values in the children's group with ACL tears were nearly identical to those in the adolescent group both with and without ACL tears. The children's group with ACL tears also had a significantly larger tibial spine height compared with healthy children (P < .001). Conclusion: Children, similar to adolescents, demonstrated the effect of the NWI on the risk of ACL tears, but only the adolescent group demonstrated stenosis with the NHI. The morphology of the knee in a child at risk for ACL rupture was not the same as that of an adolescent when considering all dimensions, but it did seem that it was more adolescent-like than child-like at the time of an ACL rupture, refuting the idea of congenital hypoplasia as a common cause.

Meniscal Bone Angle Is a Strong Predictor of Anterior Cruciate Ligament Injury

To evaluate the influence of lateral posterior tibial slope (LPTS) and meniscal bone angle (MBA) on primary anterior cruciate ligament (ACL) tear risk in an adult population through the LPTS-MBA ratio. A retrospective case-control study was performed with patients from a tertiary hospital who underwent primary ACL surgery and had preoperative magnetic resonance imaging (MRI). These subjects were matched by age and sex in a 1:1 ratio to patients who had an MRI without ACL tear. LPTS and MBA were measured on MRI scan. Quantitative data are presented in the median ± interquartile range (IQR). Identification of independent risk factors for primary ACL tear was performed using multivariable logistic regression. Receiver operating characteristics curves detected any variable with strong discriminative capacity. In total, 95 patients with primary ACL tear confirmed on MRI were matched with 95 controls (N= 190). Nearly 80% were male subjects, with a median age of 26 years. In the ACL tear group, the median value of LPTS-MBA ratio was 0.20 (IQR 0.11-0.37) versus 0.12 (IQR 0.08-0.19) in the control group (P= .001). LPTS had a median value of 4.20° in the ACL tear group (IQR 2.05-7.35°) and 2.90° in the control group (IQR, 2.05-5.00°) (P= .026), whereas MBA was 19° (IQR, 16-24°) versus 26° (IQR, 24-30°) (P= .001), respectively. Logistic regression showed that LPTS (odds ratio 1.20, 95% confidence interval 1.03-1.42, P= .021) and MBA (odds ratio 0.78, 95% confidence interval 0.71-0.85, P= .001) were independent predictors. The area under the curve (AUC) of LPTS-MBA ratio was 0.69, greater than that of LPTS alone (AUC= 0.61) but lower than that for MBA (AUC= 0.82). In this study, a reduced MBA was the strongest predictive variable associated with a primary ACL tear. A threshold of 22.35° of MBA was associated with an increased risk of ACL tear, with a sensitivity of 70% and specificity of 84%. A cut-off of 0.22 of LPTS-MBA was associated with an increased risk of ACL tear, with a sensitivity of 55% and specificity of 87%. Level III, case-control study.

Importance of Posterior Tibial Slope, Medial Tibial Plateau Slope and Lateral Tibial Plateau Slope in Anterior Cruciate Ligament Injury

Increased posterior tibial slope (PTS), medial tibial plateau slope (MTPS) and lateral tibial plateau slope (LTPS) have been proposed as potential risk factors for anterior cruciate ligament (ACL) tear. However, prior literature is inconclusive. The primary goal of the study was to investigate the relationship of MTPS, LTPS and PTS with ACL tears. The secondary goal was to determine whether injury mechanisms, age, gender, tobacco, obesity, extreme PTS (>12°) or previous injuries are risk factors in ACL tears. Three groups were identified: a study group of patients with ACL injury; a second group diagnosed with meniscal injury; and a third group of non-injured patients. Demographic data was collected. MTPS and LTPS were measured in MRI and PTS in lateral radiographs by two blinded observers. Data was analyzed using SPSS. 416 patients were included in the study. MTPS ranged from 0° to 14° (average value 5.66 ± 2.98), LTSA 0° to 16° (5.69 ± 3.5) and PTS 0° to 17° (6.75 ± 3.18). Neither MTPS, LTPS nor PTS revealed increased risk of ACL tears related with higher slopes, although high MTPS showed a decreased risk. However, when comparing traumatic groups, extreme PTS was associated with LCA tear, but no differences were found when comparing non-traumatic groups. This could mean that the importance of extreme angles in the LCA rupture may be restricted to traumatic mechanisms. Previous ACL tear was identified as a risk factor to ACL tear; increased age and a traumatic mechanism were associated with a lower risk.

Contralateral and siblings' knees are at higher risk of ACL tear for patients with a positive history of ACL tear.

Recent studies have shown that several genetic factors can cause susceptibility to anterior cruciate ligament (ACL) rupture. The aim of the present study was to evaluate certain underlying factors that increase the risk of ACL rupture. Eight hundred thirty-six patients with ACL rupture who underwent ACL reconstructive surgery from 2010 to 2013 at an academic center completed a minimum of 5years post-operation follow-up. The collected variables included sex, age, height, weight, exercise level, time interval between ACL rupture in the first knee and contralateral ACL rupture, dominant leg, side of the involved knee and sibling history of ACL rupture. The median follow-up duration was 6.5 (range: 5-8) years. Eighty-three patients (9.9%) had a contralateral ACL rupture, and 155 patients (18.5%) had siblings with a history of ACL rupture. The rate of contralateral ACL rupture was three times higher in women than in men and in patients with siblings with a history of ACL rupture than in those without such history. In addition, the risk of contralateral ACL rupture was higher in those younger than 30years of age, those with a BMI of 20-25kg/m2 and those who participated in regular sports activity. However, whether the involved knee was on the dominant or nondominant side had no effect on the incidence of contralateral ACL rupture. The results of the study showed that 69 (83.1%) of the contralateral ACL ruptures occurred within the first 2years after the primary operation. In a 5- to 8-year follow-up, one out of every ten patients had a contralateral ACL rupture, and two out of every ten patients had siblings with a history of ACL rupture. The findings suggest that having a sibling with a history of ACL rupture and being female are important risk factors for ACL rupture of the contralateral knee. III.

ANTERIOR CRUCIATE LIGAMENT INJURIES IN HIGH SCHOOL FEMALE AND MALE SOCCER ATHLETES: ARE MATCH ACL RATES BEING UNDERESTIMATED?

Background: The purpose of this study was to investigate the incidence of anterior cruciate ligament (ACL) injuries in Missouri high school female and male soccer players during the 2011-2013 seasons, using a single postseason survey sent to coaches. Our hypothesis is a single postseason survey be a feasible method to measure a large number of athletic exposures (AEs) and ACL injuries. We also hypothesize that “traditional” methods for calculating athletic exposures likely underestimate the actual burden of ACL injuries in high school soccer matches. Methods: The study was IRB approved through the University of Missouri. A web-based survey was developed and sent to every girls and boys high school soccer coach in Missouri using a Missouri State High School Activities Association (MSHSAA) database. In order to calculate AEs, questions were asked about the average number of athletes who participated in tryouts, practices, and matches along with the specific number of tryouts, practices, and matches for the 2011-2012 and 2012-2013 seasons. Coaches were also asked the number of ACL injuries their team suffered. No medical personnel were involved in filling out the surveys. Athletic exposures (AEs) were calculated using the formulas below. Match athletic exposures were calculated using a “traditional” method and also an “athlete at risk” method. The primary outcome measure was ACL injuries. Formulas for Calculation of Athletic Exposures (AEs) Tryouts &amp; Practice= (a*A) + (b*B) Match (Traditional)= (c*C) Match (Athlete at Risk)= (11*C) a = average number of players participating in tryouts A = number of tryout sessions b = average number of players participating in practices B = number of practices in a season c = average number of players participating in matches C = number of matches in a season Results: In total, 885 coaches were sent surveys and 160 (18.1%) coaches responded, with 84 coaches representing girls soccer teams and 76 representing boys teams. A total of 323,010 AEs (160,756 female and 162,254 male) were reported of which 228,608 AEs (71%) took place in practices. 94,402 AEs occurred in matches using the “traditional” method and 61,963 AEs in matches using the “athlete at risk” method. 36 ACL injuries (28 female and 8 male) were reported. Of the 28 female ACL injuries, 25 happened during high school soccer activities (23 match, 2 practice). 3 ACL injuries occurred outside of high school soccer activities (1 club soccer, 1 volleyball, 1 unknown.) All 8 male ACL injuries were suffered during a high school match. Female athletes had an ACL injury rate of 0.16/1000 AEs compared to male athletes 0.05/1000 AEs (Table 1). Female athletes had a practice ACL injury rate of 0.02/1000 AEs and there were no ACL injuries suffered by male athletes in practice. Female athletes had a match ACL injury rate of 0.47/1000 AEs using “traditional” method and 0.70/1000 AEs by the “athlete at risk” method. Male athletes had a match ACL injury rate of 0.18/1000 AEs “traditional” method and 0.28/1000 AEs “athlete at risk” method (Figure 1). Female high school soccer athletes had a 3.2x greater risk of ACL tear than male high school soccer athletes. Female athletes were 26x more likely to tear their ACL in a match compared to practice. ACL match injury rates were 50-55% higher using the “athlete at risk” method compared to “traditional” methods for calculating match injury rates. Conclusion/Significance: A single postseason survey sent to coaches was successful in measuring AEs and ACL injury rates for a large population of high school soccer athletes. This represents an economical and feasible mechanism compared to previous studies (Table 2) to measure ACL injury rates for a high number of teams. It also allows ACL injury rates to be measured for schools and teams that do not have certified athletic trainers. “Traditional” methods for calculating match ACL injury rates greatly under represent ACL injuries compared to the “athlete at risk” method which is more representative of true injury risk exposure. A very high percentage of ACL injuries occurred during matches even though matches were responsible for only 29% of AEs. If future studies have limited resources, they should consider not recording practice AEs and ACL injuries since the likelihood of an ACL injury occurring during practice is very low compared to a match. [Table: see text][Table: see text][Figure: see text]

The Combined Effect of Body Mass Index and Tibial Slope Angles on Anterior Cruciate Ligament Injury Risk in Male Knees: A Case-Control Study.

Introduction:Tibial slope angles (TSAs) have been identified as potential risk factors of anterior cruciate ligament (ACL) injury in the literature. A higher body mass index (BMI) might increase the risk of ACL tear because of greater axial compressive force. The aim of this study was to determine the relationship of these factors and the combined effect of BMI and TSA in determination of risk potential for ACL injury.Methods:The preoperative magnetic resonance (MR) images of 81 ACL-injured male knees and of 68 male individuals with no ACL injuries were evaluated by 2 radiologists to measure the TSA. The Mann-Whitney U-test was performed to indicate the significant difference in height, weight, and BMI values. The independent samples t-test was used to determine the differences between ACL-injured and non-injured groups regarding TSA values. Odds ratios were calculated by logistic regression tests, and receiver operating characteristics (ROC) curves revealed the area under the receiver operating characteristics curve (AUC) values to compare the relationships of these parameters with ACL injury.Results:Body mass index, lateral tibial slope (LTS), and medial tibial slope (MTS) were predictive of ACL risk injury. Body mass index alone had the greatest effect among these parameters, and there were no statistically significant differences in coronal tibial slope values between the ACL-ruptured and control groups. The greatest AUC was observed for the combination of BMI, MTS, and LTS.Conclusions:Body mass index, LTS, and MTS angles were associated with ACL injury risk and BMI + MTS + LTS together revealed the greatest effect on ACL injury.

Anterior Cruciate Ligament Injuries in Missouri High School Male and Female Soccer Athletes

PURPOSE: To investigate the incidence of anterior cruciate ligament (ACL) injury in Missouri High School male and female soccer players during the 2011-2013 seasons, using a retrospective method for calculating athletic exposures. METHODS: A web-based survey was created and sent to every high school soccer coach in Missouri using the Missouri State High School Activities Association (MSHSAA) database. The survey investigated the number of athletic exposures over the course of the season and number of ACL injuries for each team in both the 2011-2012 and 2012-2013 seasons. The primary outcome measure was ACL injuries. Secondary endpoints included specific characteristics of each ACL injury including contact or non-contact, position, practice or game, school grade, and playing surface. RESULTS: During the study period 330,062 athletic exposures (163,511 male and 166,551 female) were reported. 36 ACL tears (28 female and 8 male) occurred. ACL injury rates were calculated per 1000 estimated athletic exposures: Female: total, 0.17; match, 0.47; practice, 0.02. Male: total, 0.05; match, 0.18; practice, 0. Female high school soccer athletes had a 3.4 times greater risk of ACL tear than male high school soccer athletes. Female athletes were 27x more likely to tear their ACL in a match compared to practice. CONCLUSIONS: Female high school soccer athletes had an increased susceptibility to ACL tear compared to male athletes. For both female and male athletes, a large majority of ACL tears occurred during matches.

Association Between Lateral Posterior Tibial Slope, Body Mass Index, and ACL Injury Risk

Background:While body mass index (BMI), a modifiable parameter, and knee morphology, a nonmodifiable parameter, have been identified as risk factors for anterior cruciate ligament (ACL) rupture, the interaction between them remains unknown. An understanding of this interaction is important because greater compressive axial force (perhaps due to greater BMI) applied to a knee that is already at an increased risk because of its geometry, such as a steep lateral posterior tibial slope, could further increase the probability of ACL injury.Purpose:To quantify the relationship between BMI and select knee morphological parameters as potential risk factors for ACL injury.Study Design:Case-control study; Level of evidence, 3.Methods:Sagittal knee magnetic resonance imaging (MRI) files from 76 ACL-injured and 42 uninjured subjects were gathered from the University of Michigan Health System’s archive. The posterior tibial slope (PTS), middle cartilage slope (MCS), posterior meniscus height (PMH), and posterior meniscus bone angle (MBA) in the lateral compartment were measured using MRI. BMI was calculated from demographic data. The association between the knee structural factors, BMI, and ACL injury risk was explored using univariate and multivariate logistic regression.Results:PTS (P = .043) and MCS (P = .037) significantly predicted ACL injury risk. As PTS and MCS increased by 1°, odds of sustaining an ACL injury increased by 12% and 13%, respectively. The multivariate logistic regression analysis, which included PTS, BMI centered around the mean (cBMI), and their interaction, showed that this interaction predicted the odds of ACL rupture (P = .050; odds ratio, 1.03). For every 1-unit increase in BMI from the average that is combined with a 1° increase in PTS, the odds of an ACL tear increased by 15%.Conclusion:An increase in BMI was associated with increased risk of ACL tear in the presence of increased lateral posterior tibial slope. Larger values of PTS or MCS were associated with an increased risk of ACL tear.

Sport-Specific Yearly Risk and Incidence of Anterior Cruciate Ligament Tears in High School Athletes

Background: Anterior cruciate ligament (ACL) injury rates are affected by frequency and level of competition, sex, and sport. To date, no study has sought to quantify sport-specific yearly risk for ACL tears in the high school (HS) athlete by sex and sport played. Purpose: To establish evidence-based incidence and yearly risk of ACL tears in HS athletes by sex for sports performed at the varsity level across the majority of US high schools. Study Design: Meta-analysis. Methods: PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched to identify all articles reporting ACL tears per athletic exposure in HS athletes. ACL injury incidence rates (IRs) by sex and sport were calculated via meta-analysis. State athletic association guidelines were used to determine the number of exposures per season to calculate yearly risk of ACL tears. Results: The search recovered 3779 unique articles, of which 10 met our inclusion criteria, for a total of 700 ACL injuries in 11,239,029 exposures. The IR was 0.062 injuries per 1000 exposures (95% CI, 0.058-0.067). Although more injuries were recorded in males than females, females had a higher rate of injury per exposure (relative risk, 1.57; 95% CI, 1.35-1.82). Relative risk was highest in basketball (3.80; 95% CI, 2.53-5.85) and soccer (3.67; 95% CI, 2.61-5.27). While boys’ football had the highest number of ACL injuries at 273, girls’ soccer had the highest IR (0.148; 95% CI, 0.128-0.172). In girls, the highest injury risks per season were observed in soccer (1.11%; 95% CI, 0.96%-1.29%), basketball (0.88%; 95% CI, 0.71%-1.06%), and lacrosse (0.53%; 95% CI, 0.19%-1.15%). In comparison, the highest risks for boys were observed in football (0.80%; 95% CI, 0.71%-0.91%), lacrosse (0.44%; 95% CI, 0.18%-0.90%), and soccer (0.30%; 95% CI, 0.22%-0.41%). Conclusion: There is an approximately 1.6-fold greater rate of ACL tears per athletic exposure in HS female athletes than males. However, there is significant risk in both sexes, particularly in high-risk sports such as soccer, football, basketball, and lacrosse. Knowledge of sport-specific risk is essential for future injury reduction programs, parent-athlete decision making, and accurate physician counseling.

Ipsilateral Graft and Contralateral ACL Rupture at Five Years or More Following ACL Reconstruction

Injury to the ipsilateral graft used for reconstruction of the anterior cruciate ligament (ACL) or a new injury to the contralateral ACL is a devastating outcome following successful ACL reconstruction, rehabilitation, and return to sport. Little evidence exists regarding the intermediate to long-term risk of these events. The present study is a systematic review of Level-I and II prospective studies that evaluated the rate of rupture of the ACL graft and the ACL in the contralateral knee following a primary ACL reconstruction with use of a mini-open or arthroscopic bone-tendon-bone or hamstring autograft after a minimum duration of follow-up of five years. Six studies met the inclusion and exclusion criteria. The ipsilateral ACL graft rupture rate ranged from 1.8% to 10.4%, with a pooled percentage of 5.8%. The contralateral injury rate ranged from 8.2% to 16.0%, with a pooled percentage of 11.8%. This systematic review demonstrates that the risk of ACL tear in the contralateral knee (11.8%) is double the risk of ACL graft rupture in the ipsilateral knee (5.8%). Additional studies must be performed to determine predictors for these injuries and to improve our ability to avoid this devastating outcome.

Physical testing prior to returning to normal sports activity for elite athletes following ACL injury

Anterior cruciate ligament (ACL) injury is among the most frequent sports-related injuries especially in contact sports such as football, basketball, soccer and skiing. In professional sports, ACL injury has a...

Trends in serum relaxin concentration among elite collegiate female athletes

Purpose:This study was designed to investigate the relationship between serum relaxin concentration (SRC) and menstrual history and hormonal contraceptive use among elite collegiate female athletes. Evaluation of SRC in athletes is necessary, because relaxin has been associated with increased knee joint laxity and decreased anterior cruciate ligament (ACL) strength in animal models.Methods:National Collegiate Athletic Association Division I female athletes participating in sports at high risk for ACL tears – basketball, field hockey, gymnastics, lacrosse, soccer, and volleyball – were invited to participate. All participants completed a questionnaire about their menstrual history and hormonal contraceptive use. Venipuncture was performed to obtain samples of serum progesterone and relaxin. Samples were obtained during the mid-luteal phase from ovulating participants, and between the actual or projected cycle days 21 to 24, from anovulatory participants. Serum concentration of relaxin and progesterone was determined by ELISA and the data were analyzed using SPSS statistical software with significance set at P = 0.05.Results:169 female athletes participated. The mean SRC among all participants was 3.08 ± 6.66 pg/mL). The mean SRC differed significantly between those participants using hormonal contraceptives (1.41 pg/mL) and those not using hormonal contraceptives (3.08 pg/mL, P = 0.002). Mean SRC was lowest among amenorrheic participants (1.02 pg/mL) and highest among oligomenorrheic participants (3.71 pg/mL) and eumenorrheic participants (3.06 pg/mL); these differences were not significant (P = 0.53). Mean serum progesterone concentration (SPC) differed significantly between those participants using hormonal contraceptives (2.80 ng/mL), and those not using hormonal contraceptives (6.99 ng/mL, P < 0.0001).Conclusions:There is a positive correlation between serum progesterone and SRC and an attenuation of SRC with hormonal contraceptive use. Our results underscore the significant role that hormonal contraceptives can play in decreasing relaxin levels, if future investigations establish a link between relaxin levels and ligamentous injury among female athletes.