War trauma and PTSD in Ukraine's civilian population: comparing urban-dwelling to internally displaced persons.

INTRODUCTION: War in Ukraine started in March 2014 when Russia annexed Crimea and continues today in the Donbass region of Eastern Ukraine. Over 1.5 million people in these regions have been displaced from their homes. We conducted this study 36 months after the conflict began and interviewed civilians residing in Ukraine. PURPOSE: This study examines the prevalence of exposure to war trauma, rates of PTSD by symptom clusters, and whether socio-demographic factors are associated with positive scores for PTSD among civilian urban-dwelling and internally displaced persons in Ukraine during the ongoing conflict in its Donbass region. METHODS: Face-to-face interviews were conducted using a multi-stage random sample of the general population in two large cities (Kharkiv and Lviv) in Ukraine (n = 1247) and a purposive sample of internally displaced persons (n = 300), half living in each city. Exposure to trauma, symptom clusters for Posttraumatic Stress Disorder (PTSD), and overall PTSD were assessed. RESULTS: We found widespread direct exposure to conflict-related traumatic events (65%) among internally displaced people (IDPs) compared to a sizable minority (23%) of urban-dwelling people (UDPs). We found elevated prevalence of PTSD symptoms that were also uniformly spread within several socio-demographic factors. There were, however, significant differences in PTSD between (1) IDPs compared to UDPs and (2) those UDPs with Ukrainian compared to Russian ethnic identity, the former of each pair showing increased likelihoods of positive PTSD scores. CONCLUSIONS: Ukraine's adult civilians, enduring the prolonged engagement in war with Russia and Russian separatists, have elevated rates of PTSD. Moreover, those who have been displaced by the ongoing conflict (IDPs) have significantly higher levels of PTSD compared to UDPs.

Sad Eyes, Crooked Crosses: Religious Struggles, Psychological Distress and the Mediating Role of Psychosocial Resources.

In this paper, we employed data from the 2011 Miami-Dade Health Survey (n = 444) to formally test whether the association between religious struggles and psychological distress is mediated by psychosocial resources. We found that religious struggles were associated with lower levels of social support, self-esteem, the sense of control, and self-control. We also observed that religious struggles were associated with higher levels of non-specific emotional distress, depression, and anxiety, but not somatization. Our mediation analyses revealed significant indirect effects of religious struggles on emotional distress (not somatization) through social support, self-esteem, and the sense of control, but not self-control.

Wrist Fractures in Skiers and Snowboarders: Incidence, Severity, and Risk Factors Over 40 Seasons.

PURPOSE: To determine and compare the incidence and severity of wrist fractures in skiers and snowboarders. METHODS: A university-run orthopedic clinic at the base of a major ski resort has maintained an injury database spanning the years 1972 to 2012. Demographic information, equipment type, ability level, trail type and conditions, number of falls, circumstances surrounding the injury, and radiographs were collected on participants sustaining wrist fractures and compared with uninjured control participants asked the same questions, but in reference to their last fall where no injury resulted. A risk factor model for wrist fracture and severity in alpine sports was developed. RESULTS: During the 40-year period, 679 wrist fractures were identified. The incidence of wrist fracture per 1,000 days was 0.447 in snowboarders and 0.024 in skiers. In comparison with a representative sample of uninjured skiers, bivariate analyses revealed that skiers who experienced fractures were less experienced, had a greater number of falls, were on green or double black trails, and were injured owing to jumping or other reason related to technique. A higher risk for fracture was found for beginners, males younger than age 16, women older than age 50, and 4 or fewer days skiing that season. Bivariate analyses found that injured snowboarders were more likely to be female, younger, less experienced and had received less instruction than uninjured snowboarders. Higher risk for wrist fracture among snowboarders was found to be associated with age younger than 18 and less experience. CONCLUSIONS: Wrist fractures occur at an 18 times greater incidence in snowboarders than in skiers. Skiers with wrist fractures were beginners, males younger than 16, women older than 50, or those who had less participation. Snowboarders sustaining wrist fractures were younger than 18 or had less experience. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic III.

Higher frequency of osteoarthritis in patients with ACL graft rupture than in those with intact ACL grafts 30 years after reconstruction.

PURPOSE: The aim was to assess the results of anterior cruciate ligament (ACL) reconstruction regarding graft failure, knee laxity, and osteoarthritis (OA) from a longterm perspective. It was hypothesized that intact ACL graft reduces the risk for increased OA development. METHODS: The cohort comprised 60 patients with a median follow-up 31 (range 28-33) years after ACL reconstruction. They were evaluated with magnetic resonance imaging, radiography, KT-1000 arthrometer and the pivot shift test. RESULTS: Out of the 60 patients, 30 (50%) showed an intact ACL graft and 30 (50%) a ruptured or absent ACL graft. Patients with ruptured ACL grafts had more medial tibiofemoral compartment OA than those with an intact ACL graft (p = 0.0003). OA was asymmetric in patients with ruptured ACL grafts with more OA in the medial than in the lateral tibiofemoral compartment (p = 0.013) and the patellofemoral compartment (p = 0.002). The distribution of OA between compartments was similar in patients with an intact ACL graft. KT-1000 values of anterior knee laxity were higher in patients with ruptured compared to those with intact ACL grafts (p = 0.012). Side-to-side comparisons of anterior knee laxity showed higher KT-1000 values in patients with ruptured ACL graft (p = 0.0003) and similar results in those with intact graft (p = 0.09). The pivot shift grade was higher in the group with a ruptured ACL graft (p < 0.0001). CONCLUSIONS: Median 31 (range 28-33) years after ACL reconstruction, 50% of the patients showed an intact ACL graft and no side-to-side difference regarding anterior knee laxity. Patients with ruptured ACL grafts had more OA of the medial tibiofemoral compartment than those with intact ACL grafts. LEVEL OF EVIDENCE: Retrospective cohort study, Level III.

Alpine Skiing Injuries.

CONTEXT:: Alpine skiing is a popular sport worldwide but has significant risk for injury. The epidemiology of skiing-related injuries has been described, which has led to the identification of risk factors for specific types of injuries. EVIDENCE ACQUISITION:: Pertinent literature from peer-reviewed publications was reviewed. STUDY DESIGN:: Clinical review. LEVEL OF EVIDENCE:: Level 5. RESULTS:: The adoption of international standards for ski-boot-binding systems has changed the profile of skiing-related injuries over time, as has the widespread use of helmets. An understanding of mechanisms of injury, risk factors, and preventative measures may decrease the incidence of skiing-related injuries. CONCLUSION:: Advances in standards for skiing equipment have been effective at decreasing both the frequency and severity of skiing-related injuries, but additional efforts are required to improve the safety of the sport.

Photothermal Effectiveness of Magnetite Nanoparticles: Dependence upon Particle Size Probed by Experiment and Simulation.

The photothermal effect of nanoparticles has proven efficient for driving diverse physical and chemical processes; however, we know of no study addressing the dependence of efficacy on nanoparticle size. Herein, we report on the photothermal effect of three different sizes (5.5 nm, 10 nm and 15 nm in diameter) of magnetite nanoparticles (MNP) driving the decomposition of poly(propylene carbonate) (PPC). We find that the chemical effectiveness of the photothermal effect is positively correlated with particle volume. Numerical simulations of the photothermal heating of PPC supports this observation, showing that larger particles are able to heat larger volumes of PPC for longer periods of time. The increased heating duration is likely due to increased heat capacity, which is why the volume of the particle functions as a ready guide for the photothermal efficacy.

Geometric Characteristics of the Knee Are Associated With a Noncontact ACL Injury to the Contralateral Knee After Unilateral ACL Injury in Young Female Athletes.

BACKGROUND: Contralateral anterior cruciate ligament (CACL) injury after recovery from a first-time ACL rupture occurs at a high rate in young females; however, little is known about the risk factors associated with bilateral ACL trauma. HYPOTHESIS: The geometric characteristics of the contralateral knee at the time of the initial ACL injury are associated with risk of suffering a CACL injury in these female athletes. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Sixty-two female athletes who suffered their first noncontact ACL injury while participating in sports at the high school or college level were identified, and geometry of the femoral notch, ACL, tibial spines, tibial subchondral bone, articular cartilage surfaces, and menisci of the contralateral, uninjured, knee was characterized in 3 dimensions. We were unable to contact 7 subjects and followed the remaining 55 until either a CACL injury or an ACL graft injury occurred or, if they were not injured, until the date of last contact (mean, 34 months after their first ACL injury). Cox regression was used to identify risk factors for CACL injury. RESULTS: Ten (18.2%) females suffered a CACL injury. Decreases of 1 SD in femoral intercondylar notch width (measured at its outlet and anterior attachment of the ACL) were associated with increases in the risk of suffering a CACL injury (hazard ratio = 1.88 and 2.05, respectively). Likewise, 1 SD decreases in medial-lateral width of the lateral tibial spine, height of the medial tibial spine, and thickness of the articular cartilage located at the posterior region of the medial tibial compartment were associated with 3.59-, 1.75-, and 2.15-fold increases in the risk of CACL injury, respectively. CONCLUSION: After ACL injury, subsequent injury to the CACL is influenced by geometry of the structures that surround the ACL (the femoral notch and tibial spines). This information can be used to identify individuals at increased risk for CACL trauma, who might benefit from targeted risk-reduction interventions.

Characterization of Prepractice Injury Prevention Exercises of High School Athletic Teams.

BACKGROUND: Static and dynamic exercises are performed before activity to decrease injury risk and increase performance. Although evidence supports using dynamic over static stretching and performing Fédération Internationale de Football Association (FIFA) 11+ as a dynamic prepractice routine, we do not know the frequency at which these exercises are utilized in high school populations. HYPOTHESIS: We hypothesize that there is a wide variety of preparticipation exercises performed by high school athletes, and that few high school teams perform FIFA 11+ as an injury prevention program in its entirety. STUDY DESIGN: Observational study. LEVEL OF EVIDENCE: Level 4. METHODS: High school prepractice routines were observed for 185 teams (football, soccer, basketball, and lacrosse) over 1 season. The percentages of team warm-up routines that included components of FIFA 11+ were calculated, and the chi-square test was used to compare sex, sport, and level of competition. RESULTS: Of a total 644 warm-up observations, 450 (69.9%) included only non-FIFA 11+ exercises, 56 (8.7%) included at least 1 FIFA 11+ exercise, and 38 (5.9%) included only jogging; 69 (10.6%) consisted only of sport-specific activities. The type of warm-up differed significantly between males and females ( P = 0.002), sports ( P < 0.001), and level of competition ( P < 0.001). Static stretching and athletes stretching on their own were observed in 14% and 15% of all observations. No team performed the FIFA 11+ injury prevention routine in its entirety. CONCLUSION: The type of warm-up differed by sex, sport, and level of competition. Static stretching was performed more frequently than anticipated, and an entire FIFA 11+ warm-up was never performed. CLINICAL RELEVANCE: We need to identify the exercises that decrease injury and increase performance and better inform the athletic population about the risks and benefits of static and dynamic warm-up programs.

Relationship between geometry of the extensor mechanism of the knee and risk of anterior cruciate ligament injury.

The complex inter-segmental forces that are developed across an extended knee by body weight and contraction of the quadriceps muscle group transmits an anteriorly directed force on the tibia that strain the anterior cruciate ligament (ACL). We hypothesized that a relationship exists between geometry of the knees extensor mechanism and the risk of sustaining a non-contact ACL injury. Geometry of the extensor mechanism was characterized using MRI scans of the knees of 88 subjects that suffered their first non-contact ACL injury and 88 matched control subjects with normal knees that were on the same team. The orientation of the patellar tendon axis was measured relative to the femoral flexion-extension axis to determine the extensor moment arm (EMA), and relative to tibial long axis to measure coronal patellar tendon angle (CPTA) and sagittal patellar tendon angle (SPTA). Associations between these parameters and ACL injury risk were tested with and without adjustment for flexion and internal rotation position of the tibia relative to the femur during MRI data acquisition. After adjustment for internal rotation position of the tibia relative to the femur there were no associations between EMA, CPTA, and SPTA and risk of suffering an ACL injury. However, increased internal rotation position of the tibia relative to the femur was significantly associated with increased risk of ACL injury in female athletes both in univariate analysis (Odds Ratio = 1.16 per degree of internal rotation of the tibia, p = 0.002), as well as after adjustment for EMA, CPTA, and SPTA.: © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:965-973, 2017.

Multivariate Analysis of the Risk Factors for First-Time Noncontact ACL Injury in High School and College Athletes: A Prospective Cohort Study With a Nested, Matched Case-Control Analysis.

BACKGROUND: Multivariate analysis that identifies the combination of risk factors associated with anterior cruciate ligament (ACL) trauma is important because it provides insight into whether a variable has a direct causal effect on risk or an indirect effect that is mediated by other variables. It can also reveal risk factors that might not be evident in univariate analyses; if a variable's effect is moderated by other variables, its association with risk may be apparent only after adjustment for the other variables. Most important, multivariate analyses can identify combinations of risk factors that are more predictive of risk than individual risk factors. HYPOTHESIS: A diverse combination of risk factors predispose athletes to first-time noncontact ACL injury, and these relationships are different for male and female athletes. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Athletes competing in organized sports at the high school and college levels participated in this study. Data from injured subjects (109 suffering an ACL injury) and matched controls (227 subjects) from the same athletic team were analyzed with multivariate conditional logistic regression to examine the effects of combinations of variables (demographic characteristics, joint laxity, lower extremity alignment, strength, and personality traits) on the risk of suffering their first ACL injury and to construct risk models. RESULTS: For male athletes, increases in anterior-posterior displacement of the tibia relative to the femur (knee laxity), posterior knee stiffness, navicular drop, and a decrease in standing quadriceps angle were jointly predictive of suffering an ACL injury. For female athletes the combined effects of having a parent who had suffered an ACL injury and increases in anterior-posterior knee laxity and body mass index were predictive of ACL injury. CONCLUSION: Multivariate models provided more information about ACL injury risk than individual risk factors. Both male and female risk models included increased anterior-posterior knee laxity as a predictor of ACL injury but were otherwise dissimilar.

Evaluation of an Algorithm to Predict Menstrual-Cycle Phase at the Time of Injury.

CONTEXT: Women are 2 to 8 times more likely to sustain an anterior cruciate ligament (ACL) injury than men, and previous studies indicated an increased risk for injury during the preovulatory phase of the menstrual cycle (MC). However, investigations of risk rely on retrospective classification of MC phase, and no tools for this have been validated. OBJECTIVE: To evaluate the accuracy of an algorithm for retrospectively classifying MC phase at the time of a mock injury based on MC history and salivary progesterone (P4) concentration. DESIGN: Descriptive laboratory study. SETTING: Research laboratory. PARTICIPANTS: Thirty-one healthy female collegiate athletes (age range, 18-24 years) provided serum or saliva (or both) samples at 8 visits over 1 complete MC. MAIN OUTCOME MEASURE(S): Self-reported MC information was obtained on a randomized date (1-45 days) after mock injury, which is the typical timeframe in which researchers have access to ACL-injured study participants. The MC phase was classified using the algorithm as applied in a stand-alone computational fashion and also by 4 clinical experts using the algorithm and additional subjective hormonal history information to help inform their decision. To assess algorithm accuracy, phase classifications were compared with the actual MC phase at the time of mock injury (ascertained using urinary luteinizing hormone tests and serial serum P4 samples). Clinical expert and computed classifications were compared using κ statistics. RESULTS: Fourteen participants (45%) experienced anovulatory cycles. The algorithm correctly classified MC phase for 23 participants (74%): 22 (76%) of 29 who were preovulatory/anovulatory and 1 (50%) of 2 who were postovulatory. Agreement between expert and algorithm classifications ranged from 80.6% (κ = 0.50) to 93% (κ = 0.83). Classifications based on same-day saliva sample and optimal P4 threshold were the same as those based on MC history alone (87.1% correct). Algorithm accuracy varied during the MC but at no time were both sensitivity and specificity levels acceptable. CONCLUSIONS: These findings raise concerns about the accuracy of previous retrospective MC-phase classification systems, particularly in a population with a high occurrence of anovulatory cycles.

Religious Involvement and Perceptions of Control: Evidence from the Miami-Dade Health Survey.

This study uses data collected through the 2011 Miami-Dade Health Survey (n = 444) to test whether religious involvement is associated with three distinct control beliefs. Regression results suggest that people who exhibit high levels of religious involvement tend to report higher levels of the sense of control, self-control, and the health locus of control than respondents who exhibit low levels of religious involvement. Although this study suggests that religious involvement can promote perceptions of control over one's own life, this pattern is apparently concentrated at the high end of the distribution for religious involvement, indicating a threshold effect.

Relationship between synovial fluid biomarkers of articular cartilage metabolism and the patient's perspective of outcome depends on the severity of articular cartilage damage following ACL trauma.

Anterior cruciate ligament (ACL) trauma often occurs in combination with injury to the articular cartilage of the knee, this can result in earlier radiographic evidence of post traumatic osteoarthritis (OA) of the knee compared to the contralateral, ACL intact knee; however, the biomechanical and biological mechanisms associated with the onset and progression of this disease are not understood. We sought to gain insight into the mechanisms by determining the relationship between articular cartilage injury associated with ACL trauma and the expression of synovial fluid biomarkers of articular cartilage metabolism, and to evaluate the relationship between these biomarkers and the patient's perspective of the outcomes. Synovial fluid samples were acquired from 39 ACL injured subjects at an average of 10 weeks after injury, and 32 control subjects with normal knees (documented with clinical exam and MRI assessment). Subjects in the ACL-injured group were classified as low-risk for future OA if they displayed an International Cartilage Repair Society (ICRS) Grade 2 articular cartilage lesion or less and high-risk for future OA if they had an ICRS Grade 3A articular cartilage lesion. The patient's perspective of the injury was evaluated with the Knee Injury and Osteoarthritis Outcomes Score (KOOS). There were no significant differences in mean concentrations of the markers of type II collagen metabolism (CPII, C2C, and C1,2C) or the aggrecan breakdown Alanine-Arginine-Glycine-Serine (ARGS) -fragment between control subjects and the subjects in the low- and high-risk groups (p-value range: 0.80-0.43). Associations between ARGS-aggrecan concentration and KOOS subscales of symptoms and pain were significantly different between the low- and high-risk groups (p = 0.03 and p = 0.01, respectively). Likewise, there was strong evidence in support of an association between the markers of type II collagen metabolism (C1,2C and CPII concentrations) and the KOOS subscale of pain between the low- and high-risk groups (p = 0.051 and 0.077, correspondingly). In ACL injured subjects with concomitant Grade 3A articular cartilage injuries, concentrations of synovial fluid ARGS-aggrecan were directly associated with improvements in KOOS symptoms and pain. These findings suggest the possible involvement of ARGS-aggrecan in a localized tissue repair response involving an increase in aggrecan turnover following severe knee trauma. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:820-827, 2016.

Combined anatomic factors predicting risk of anterior cruciate ligament injury for males and females.

BACKGROUND: Knee joint geometry has been associated with risk of suffering an anterior cruciate ligament (ACL) injury; however, few studies have utilized multivariate analysis to investigate how different aspects of knee joint geometry combine to influence ACL injury risk. HYPOTHESES: Combinations of knee geometry measurements are more highly associated with the risk of suffering a noncontact ACL injury than individual measurements, and the most predictive combinations of measurements are different for males and females. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: A total of 88 first-time, noncontact, grade III ACL-injured subjects and 88 uninjured matched-control subjects were recruited, and magnetic resonance imaging data were acquired. The geometry of the tibial plateau subchondral bone, articular cartilage, and meniscus; geometry of the tibial spines; and size of the femoral intercondylar notch and ACL were measured. Multivariate conditional logistic regression was used to develop risk models for ACL injury in females and males separately. RESULTS: For females, the best fitting model included width of the femoral notch at its anterior outlet and the posterior-inferior-directed slope of the lateral compartment articular cartilage surface, where a millimeter decrease in notch width and a degree increase in slope were independently associated with a 50% and 32% increase in risk of ACL injury, respectively. For males, a model that included ACL volume and the lateral compartment posterior meniscus to subchondral bone wedge angle was most highly associated with risk of ACL injury, where a 0.1 cm3 decrease in ACL volume (approximately 8% of the mean value) and a degree decrease in meniscus wedge angle were independently associated with a 43% and 23% increase in risk, correspondingly. CONCLUSION: Combinations of knee joint geometry measurements provided more information about the risk of noncontact ACL injury than individual measures, and the aspects of geometry that best explained the relationship between knee geometry and the risk of injury were different between males and females. Consequently, a female with both a decreased femoral notch width and an increased posterior-inferior-directed lateral compartment tibial articular cartilage slope combined or a male with a decreased ACL volume and decreased lateral compartment posterior meniscus angle were most at risk for sustaining an ACL injury.

Fe3O4 nanoparticles as robust photothermal agents for driving high barrier reactions under ambient conditions.

Magnetite nanoparticles (MNPs) show remarkable stability during extreme photothermal heating (≥770 K), displaying no change in size, crystallinity, or surfactants. The heat produced is also shown as chemically useful, driving the high-barrier thermal decomposition of polypropylene carbonate. This suggests MNPs are better photothermal agents (compared to gold nanoparticles), for photothermally driving high-barrier chemical transformations.

Tibial articular cartilage and meniscus geometries combine to influence female risk of anterior cruciate ligament injury.

Tibial plateau subchondral bone geometry has been associated with the risk of sustaining a non-contact ACL injury; however, little is known regarding the influence of the meniscus and articular cartilage interface geometry on risk. We hypothesized that geometries of the tibial plateau articular cartilage surface and meniscus were individually associated with the risk of non-contact ACL injury. In addition, we hypothesized that the associations were independent of the underlying subchondral bone geometry. MRI scans were acquired on 88 subjects that suffered non-contact ACL injuries (27 males, 61 females) and 88 matched control subjects that were selected from the injured subject's teammates and were thus matched on sex, sport, level of play, and exposure to risk of injury. Multivariate analysis of the female data revealed that increased posterior-inferior directed slope of the middle articular cartilage region and decreased height of the posterior horn of the meniscus in the lateral compartment were associated with increased risk of sustaining a first time, non-contact ACL injury, independent of each other and of the slope of the tibial plateau subchondral bone. No measures were independently related to risk of non-contact ACL injury among males.

The Effects of Level of Competition, Sport, and Sex on the Incidence of First-Time Noncontact Anterior Cruciate Ligament Injury.

BACKGROUND: Anterior cruciate ligament (ACL) injuries are disabling and are associated with the early onset of posttraumatic osteoarthritis. Little is known regarding the incidence rate of first-time noncontact ACL injuries sustained during athletic events and how they are independently influenced by level of competition, type of sport, and the participant's sex. HYPOTHESIS: Level of competition (college or high school), type of sport (soccer, basketball, lacrosse, field hockey, football, rugby, volleyball), and the athlete's sex independently influence the incidence rate of first-time noncontact ACL injuries. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Between fall 2008 and spring 2012, first-time noncontact ACL injury data were collected from 8 colleges and 18 high schools across 7 sports. Athlete exposure was computed retrospectively using team rosters and numbers of scheduled practices and games. Injury incidence rates (IRs) were computed per 1000 athlete exposures. The independent effects of level of competition, sport, and sex on ACL injury risk were estimated by Poisson regression. RESULTS: Colleges reported 48 ACL injuries with 320,719 athlete exposures across all sports studied (IR = 0.150 per 1000 person-days), while high schools reported 53 injuries with 873,057 athlete exposures (IR = 0.061). After adjustment for differences in sport and sex, college athletes had a significantly higher injury risk than did high school athletes (adjusted relative risk [RR], 2.38; 95% CI, 1.55-3.54). The overall IR for female athletes was 0.112 compared with 0.063 for males. After adjustment for sport and level of play, females were more than twice as likely to have a first-time ACL injury compared with males (RR, 2.10; 95% CI, 1.34-3.27). With lacrosse as the reference group, risk of first-time noncontact ACL injury was significantly higher for soccer players (RR, 1.77) and for rugby players (RR, 2.23), independent of level of play and sex. CONCLUSION: An athlete's risk of having a first-time noncontact ACL injury is independently influenced by level of competition, the participant's sex, and type of sport, and there are no interactions between their effects. Female college athletes have the highest risk of having a first-time noncontact ACL injury among the groups studied.

A decreased volume of the medial tibial spine is associated with an increased risk of suffering an anterior cruciate ligament injury for males but not females.

Measurements of tibial plateau subchondral bone and articular cartilage slope have been associated with the risk of suffering anterior cruciate ligament (ACL) injury. Such single-plane measures of the tibial plateau may not sufficiently characterize its complex, three-dimensional geometry and how it relates to knee injury. Further, the tibial spines have not been studied in association with the risk of suffering a non-contact ACL injury. We questioned whether the geometries of the tibial spines are associated with non-contact ACL injury risk, and if this relationship is different for males and females. Bilateral MRI scans were acquired on 88 ACL-injured subjects and 88 control subjects matched for sex, age and sports team. Medial and lateral tibial spine geometries were characterized with measurements of length, width, height, volume and anteroposterior location. Analyses of females revealed no associations between tibial spine geometry and risk of ACL injury. Analyses of males revealed that an increased medial tibial spine volume was associated with a decreased risk of ACL injury (OR = 0.667 per 100 mm(3) increase). Smaller medial spines could provide less resistance to internal rotation and medial translation of the tibia relative to the femur, subsequently increasing ACL strains and risk of ACL injury.

Relationship Between the Risk of Suffering a First-Time Noncontact ACL Injury and Geometry of the Femoral Notch and ACL: A Prospective Cohort Study With a Nested Case-Control Analysis.

BACKGROUND: The morphometric characteristics of the anterior cruciate ligament (ACL) and the femoral intercondylar notch within which it resides have been implicated as risk factors for injuries to this important stabilizer of the knee. Prior research has produced equivocal results with differing methodologies, and consequently, it is unclear how these characteristics affect the injury risk in male and female patients. HYPOTHESIS: The morphometric characteristics of the ACL and femoral intercondylar notch are individually and independently associated with the risk of suffering a noncontact ACL injury, and these relationships are different in male and female patients. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: Magnetic resonance imaging scans of the bilateral knees were obtained on 88 case-control pairs (27 male, 61 female) matched for age, sex, and participation on the same sports team. Patients had suffered a grade III, first-time, noncontact ACL tear. The femoral notch width at 4 locations, the thickness of the bony ridge at the anteromedial outlet of the femoral notch, the femoral notch volume, ACL volume, and ACL cross-sectional area were measured. RESULTS: Multivariate analysis of combined data from male and female patients revealed that decreased ACL volume (odds ratio [OR], 0.829), decreased femoral notch width (OR, 0.700), and increased bony ridge thickness at the anteromedial outlet of the femoral notch (OR, 1.614) were significant independent predictors of an ACL injury. Separate analyses of male and female patients indicated that the femoral notch ridge may be more strongly associated with a risk in female patients, while ACL volume is more strongly associated with a risk in male patients. However, statistical analysis performed with an adjustment for body weight strengthened the association between ACL volume and the risk of injuries in female patients. CONCLUSION: Morphometric features of both the ACL and femoral notch combine to influence the risk of suffering a noncontact ACL injury. When included together in a multivariate model that adjusts for body weight, the effects of the morphometric measurements are similar in male and female patients. If body weight is not taken into consideration, ACL volume is not associated with a risk in female patients.

Increased slope of the lateral tibial plateau subchondral bone is associated with greater risk of noncontact ACL injury in females but not in males: a prospective cohort study with a nested, matched case-control analysis.

BACKGROUND: There is an emerging consensus that increased posterior-inferior directed slope of the subchondral bone portion of the tibial plateau is associated with increased risk of suffering an anterior cruciate ligament (ACL) injury; however, most of what is known about this relationship has come from unmatched case-control studies. These observations need to be confirmed in more rigorously designed investigations. HYPOTHESIS: Increased posterior-inferior directed slope of the medial and lateral tibial plateaus are associated with increased risk of suffering a noncontact ACL injury. STUDY DESIGN: Case-control study; Level of evidence, 3. METHODS: In sum, 176 athletes competing in organized sports at the college and high school levels participated in the study: 88 suffering their first noncontact ACL injury and 88 matched controls. Magnetic resonance images were acquired, and geometry of the subchondral bone portion of the tibial plateau was characterized on each athlete bilaterally by measuring the medial and lateral tibial plateau slopes, coronal tibial slope, and the depth of the medial tibial plateau. Comparisons between knees of the same person were made with paired t tests, and associations with injury risk were assessed by conditional logistic regression analysis of ACL-injured and control participants. RESULTS: Controls exhibited side-to-side symmetry of subchondral bone geometry, while the ACL-injured athletes did not, suggesting that the ACL injury may have changed the subchondral bone geometry. Therefore, the uninjured knees of the ACL-injured athletes and the corresponding limbs of their matched controls were used to assess associations with injury risk. Analyses of males and females as a combined group and females as a separate group showed a significant association between ACL injury risk and increased posterior-inferior directed slope of the lateral tibial plateau slope. This relationship was not apparent when males were analyzed as a group. Multivariate analyses indicated that these results were independent of the medial tibial plateau slope, coronal tibial slope, and depth of the medial tibial plateau, which were not associated with ACL injury. CONCLUSION: There is a 21.7% increased risk of noncontact ACL injury with each degree increase of the lateral tibial plateau slope among females but not among males. The medial tibial plateau slope, coronal tibial slope, and depth of the medial tibial plateau were not associated with risk of injury for females or males.