Quadriceps angle and risk of injury among high school cross-country runners

The Running Readiness Scale and Injury in Collegiate Track and Field and Cross Country Athletes

CONTEXT

Track and field and cross country athletes experience high rates of lower extremity injuries. The Running Readiness Scale (RRS) may help determine which athletes have a higher likelihood of lower extremity injury.

OBJECTIVE

To determine if RRS performance at the start of the season was related to the likelihood of experiencing a lower extremity injury during the subsequent track and field or cross country season.

DESIGN

Prospective cohort study.

SETTING

University.

PATIENTS OR OTHER PARTICIPANTS

One hundred thirteen National Collegiate Athletic Association Division III track and field athletes in running, jumping, and vaulting events and cross country runners (50 women and 63 men, age = 19.9 ± 1.3 years [mean ± SD]).

MAIN OUTCOME MEASURE(S)

Athletes were assessed on RRS tasks (double-leg hopping, plank, step-ups, single-leg squats, and wall sit) at the start of their season and were then observed by team athletic trainers during the season for occurrence of lower extremity injuries that resulted in missing 1 or more practices or meets. Adjusted odds ratios and 95% confidence intervals were used to assess the likelihood of lower extremity injury.

RESULTS

Thirty-seven athletes (32.7%) experienced a lower extremity injury. Athletes scoring ≤3 on the RRS were almost 5 times more likely to experience a lower extremity injury (adjusted odds ratios = 4.8; 95% confidence interval: 2.1, 11.3) than athletes scoring ≥4. Athletes who failed the double-leg hop or wall sit task were more likely to experience a lower extremity injury (P < .05).

CONCLUSIONS

Track and field and cross country athletes with RRS scores of ≤3 had a higher likelihood of lower extremity injury than those with scores of ≥4.

Evaluation of the relationship between the bone alignment of the lower extremity and the importance of Q angle in male athletes

INTRODUCTION

Evaluating the mechanical-anatomical alignment and angles of the knee joint is crucial for athletes. We aimed to analyse the relationship between lower extremity bone alignment and the importance of the Q angle (QA) in male athletes.

METHODS

We included 38 male professional football athletes without any alignment or varus-valgus deformity who actively played football in various football clubs in Istanbul. This study was conducted using quantitative research methods within the scope of a cohort study design and employed a correlational survey method. A health specialist at the orthopaedic outpatient clinic of the Haseki Training and Research Hospital, Istanbul, evaluated the participants' lower extremity bone alignment using standing anteroposterior radiographs and assessed the QA using the goniometric measurement method. The anatomical lateral distal femoral angle (aLDFA), medial proximal tibial angle (MPTA) and QA data were analysed to assess lower extremity straightness.

RESULTS

Significant relationships between the right and left leg aLDFA, MPTA and QA values of the participants' lower extremity mechanical axis values and between the aLDFA and right leg QA values (r = 0.380, p = 0.019) were found. These relationships were attributed to the difference between proximal and distal alignments of the lower extremities. The correlation between QA and certain mechanical alignment parameters was due to unilateral and bilateral symmetrical arrangements of the lower extremities.

CONCLUSIONS

The parameters of lower extremity mechanical-anatomical alignment are considered preliminary indicators of relationships among sports injuries, structural factors and predisposition to such injuries. Individual differences in the angular values of mechanical-anatomical alignment and the application of different methods for determining these angles have revealed some uncertainties. We determined the mechanical axis data of football athletes who predominantly used their lower extremities using the most reliable methods and examined the relationship among the right and left leg aLDFA, MPTA and QA values. We believe that our findings provide insights and guidance for experts in the field.

Impact of the Quadriceps Angle on Health and Injury Risk in Female Athletes

The quadriceps angle, knowns as the Q-angle, is an anatomical feature of the human body that is still largely unknown and unstudied despite its initial discovery in the 1950s. The strength disparities between male and female athletes are largely determined by the Q-angle. In spite of a growing number of women participating in sports such as track, tennis, soccer, gymnastics, basketball, volleyball, swimming, and softball, studies investigating injuries in this group are scanty. Even though the Q-angle has been the subject of many studies carried out all over the world, a review of the literature regarding its effects on health and injury risk in female athletes has not yet been completed. The aim of this review is to examine the crucial role of the Q-angle in the biomechanics of the knee joint and its effect on performance and injury risk, particularly in female athletes. Furthermore, we highlight the greater likelihood of knee-related injuries seen in female athletes being caused by the Q-angle. Athletes, coaches, healthcare professionals, and athletic trainers can better comprehend and prepare for the benefits and drawbacks resulting from the Q-angle by familiarizing themselves with the research presented in this review.

Incidence and biomechanical risk factors for running-related injuries: A prospective cohort study

Background

Injuries among runners is significant, yet the contributing risk factors remain elusive. The objective of this study was to examined the incidence and biomechanical elements associated with running-related injuries.

Methods

A 24-week prospective study was carried out. Injury incidence was calculated per 1000 h of running, with participants completing bi-monthly online questionnaires. Biomechanical risk factors, encompassing plantar pressure, muscle strength of hip and knee muscles, core stability, dorsiflexion, passive hip internal rotation, lower extremity length, Q-angle, and shank-forefoot alignment, were assessed at baseline. Logistic regression was used to investigate the relationship between injury incidence and these biomechanical risk factors.

Results

Ninety-eight runners participated in the study. Injury incidence was 8.1 per 1000 h of running, with 41 runners experiencing musculoskeletal injuries during the follow-up period. The knee emerged as the most commonly affected joint, constituting 28.4 % of injuries. The Odds Ratio for hip external rotator muscle strength was .84 (95 % Confidence Interval = .71 - .99).

Conclusion

Greater force during hip external rotation was identified as a protective factor against running injuries. These findings bear significance for the formulation and implementation of preventive strategies.

Clinical assessment, treatment, and referral trends for adolescent runners seeking care at an injured runners' clinic

PURPOSE

Over a 10-year time frame, this study aimed to evaluate diagnosis, treatment, and referral trends for adolescent runners seeking care for running-related injuries (RRIs) at a clinic that specializes in running medicine.

METHODS

This study was a retrospective chart review of 392 adolescent runners (2,326 encounters) who sought care for RRIs between the years 2011 and 2021. Descriptive statistics were used to summarize clinical assessments, referrals, assistive devices, and medications prescribed or administered overall and by injury type. Chi-square analyses were used to compare proportions of services rendered across the 10-year time frame.

RESULTS

Patients most frequently received manual evaluations or special tests during clinic visits. Most visits resulted in at least one referral (91%), primarily for physical therapy or gait-training. Assistive devices and medications/supplements were offered at only 18% of patient visits. The majority of assessments (X2 = 69.7, p = 0.002), treatments (X2: 23.6-43.8, p: <  0.001-0.003), and referrals (X2 = 132, p <  0.001) were for shin injuries. Larger proportions of nutrition assessments (X2 = 40.7, p <  0.001), interventions (X2 = 26.8, p = 0.003), and referrals (X2 = 27.5, p = 0.002) were performed in or after the year 2015.

CONCLUSION

Clinic visits for shin injuries required the most clinical resources per episode of care. There were observed shifts in clinical assessment and treatment approaches to include more expanded nutritional and physiologic considerations.

What is the influence of biomechanical variables on the Y balance test performance in recreational runners?

BACKGROUND

Asymmetries and poor Y balance test (YBT) performance are associated with an increased risk of injuries in athletes. The aim of this study was to investigate the association between YBT performance with biomechanical variables in runners.

METHODS

The runners underwent the YBT, followed by the assessment of center of pressure, plank position, muscle strength (MS) of hip flexors, extensors, abductors, and external rotators, knee extensors, ankle dorsiflexion range of motion (ROM), Q angle, forefoot alignment, and passive hip internal rotation. Associations between variables were examined using multiple linear regression models with the Bayesian Information Criterion.

RESULTS

122 cases were analyzed. The R2 values were 0.38; 0.05; 0.06; and 0.15 for the anterior, posteromedial, posterolateral and composite directions models, respectively. The anterior reach in the YBT was associated with ankle dorsiflexion ROM [Sβ 95%IC: 0.43 (0.32-0.55)], passive hip internal rotation [Sβ 95%IC: 0.35 (0.24-0.47)], MS of the hip extensors [Sβ 95%IC: 0.19 (0.07-0.31)] and forefoot alignment [Sβ 95%IC: 0.14 (-0.25-0.02)]. The posteromedial and posterolateral reach were associated with MS of the hip flexors [Sβ 95%IC: 0.23 (0.09-0.37) and 0.24 (0.11-0.38)], respectively. The composite score was associated with MS of the hip flexors [Sβ 95%IC: 0.31 (0.18-0.45)], ankle dorsiflexion ROM [Sβ 95%IC: 0.24 (0.10-0.37)] and Q angle [Sβ 95%IC: 0.18 (0.04-0.31)].

CONCLUSION

YBT performance in different directions demonstrated specific associations with key biomechanical factors.

Morphology and transverse alignment of the patella have no effect on knee gait characteristics in healthy Chinese adults over the age of 40 years

Background: The influence of patella morphology and horizontal alignment on knee joint kinematics and kinetics remains uncertain. This study aimed to assess patella morphology and transverse alignment in relation to knee kinetics and kinematics in individuals without knee conditions. A secondary objective was to investigate the impact of femur and tibia alignment and shape on knee gait within this population. Patients and methods: We conducted a prospective collection of data, including full-leg anteroposterior and skyline X-ray views and three-dimensional gait data, from a cohort comprising 54 healthy individuals aged 40 years and older. Our study involved correlation and logistic regression analyses to examine the influence of patella, femur, and tibia morphology and alignment on knee gait. Results: The patellar tilt angle or the patella index did not show any significant relationships with different aspects of gait in the knee joint, such as velocity, angle, or moment (p > 0.05, respectively). Using multivariate logistic regression analysis, we found that the tibiofemoral angle and the Q angle both had a significant effect on the adduction angle (OR = 1.330, 95%CI 1.033-1.711, p = 0.027; OR = 0.475, 95%CI 0.285-0.792, p = 0.04; respectively). The primary variable influencing the knee adduction moment was the tibiofemoral angle (OR = 1.526, 95% CI 1.125-2.069, p = 0.007). Conclusion: In healthy Chinese individuals aged over 40, patella morphology and transverse alignment do not impact knee gait. However, the femoral-tibial angle has a big impact on the knee adduction moment.

Risk Factors for Running-Related Injury in High School and Collegiate Cross-country Runners: A Systematic Review

OBJECTIVE: To summarize and describe risk factors for running-related injuries (RRIs) among high school and collegiate cross-country runners. DESIGN: Descriptive systematic review. LITERATURE SEARCH: Four databases (Scopus, SPORTDiscus, CINAHL, Cochrane) were searched from inception to August 2023. STUDY SELECTION CRITERIA: Studies assessing RRI risk factors in high school or collegiate runners using a prospective design with at least 1 season of follow-up were included. DATA SYNTHESIS: Results across each study for a given risk factor were summarized and described. The NOS and GRADE frameworks were used to evaluate quality of each study and certainty of evidence for each risk factor. RESULTS: Twenty-four studies were included. Overall, study quality and certainty of evidence were low to moderate. Females or runners with prior RRI or increased RED-S (relative energy deficiency in sport) risk factors were most at risk for RRI, as were runners with a quadriceps angle of >20° and lower step rates. Runners with weaker thigh muscle groups had increased risk of anterior knee pain. Certainty of evidence regarding training, sleep, and specialization was low, but suggests that changes in training volume, poorer sleep, and increased specialization may increase RRI risk. CONCLUSION: The strongest predictors of RRI in high school and collegiate cross-country runners were sex and RRI history, which are nonmodifiable. There was moderate certainty that increased RED-S risk factors increased RRI risk, particularly bone stress injuries. There was limited evidence that changes in training and sleep quality influenced RRI risk, but these are modifiable factors that should be studied further in this population. J Orthop Sports Phys Ther 2024;54(2):1-13. Epub 16 November 2023. doi:10.2519/jospt.2023.11550.

Intrinsic and extrinsic factors contributing to running-related lower limb injuries among adolescent runners

The purpose of this study was to assess which combination of intrinsic and extrinsic factors contribute to running-related injury (RRI)among adolescent cross-country, track, and long-distance runners. We conducted a retrospective study at a hospital-affiliated sports injury prevention centre of 130 adolescent runners (F: 62.1%, M: 37.9%; cross-country: 34.1%, track: 56.1%, long-distance running: 9.8%) who underwent an Injury Prevention Evaluation between 2013 and 2021. The evaluation included a questionnaire on personal and training factors, and standardised physical assessments. We used a binomial logistic regression to assess the influence of demographics, lower extremity strength and alignment, training (running volume and intensity, weight training), and dietary factors on RRIs. There were 38 adolescent runners who reported RRIs (ankle sprains: N = 16, shin splints: N = 9, stress fractures: N = 13). Female sex (odds ratio [OR]: 4.58 [1.37, 15.37]; p = 0.01), reduced weekday hours of sleep (OR: 1.75 [1.04, 2.95]; p = 0.04), reduced hip abduction strength (OR: 1.02 [1.00, 1.04]; p = 0.05), and intention to lose weight to improve athletic performance (OR: 4.58 [1.00, 21.28]; p = 0.05) were associated with RRIs. These intrinsic and extrinsic risk factors may represent targets for injury prevention for adolescent runners.

A Comparison of Factors Associated with Running-Related Injuries between Adult and Adolescent Runners

Background

There are multiple personal and environmental factors that influence the risk of developing running-related injuries (RRIs). However, it is unclear how these key clinical factors differ between adult and adolescent runners.

Purpose

The purpose of this study was to compare anthropometric, training, and self-reported outcomes among adult and adolescent runners with and without lower extremity musculoskeletal RRIs.

Study Design

Cross-sectional study.

Methods

Questionnaire responses and clinical assessment data were extracted from 38 adult runners (F: 25, M: 13; median age: 23 [range 18-36]) and 91 adolescent runners (F: 56, M: 35; median age: 15 [range 14-16]) who underwent a physical injury prevention evaluation at a hospital-affiliated sports injury prevention center between 2013 and 2021. Participants were sub-grouped into those with (adults: 25; adolescents: 38) and those without (adults: 13; adolescents: 53) a history of self-reported RRIs based on questionnaire responses. Multivariate analyses of covariance (MANCOVA) covarying for gender were conducted to compare outcomes across groups.

Results

Adult runners had lower Functional Movement Screen™ (FMS™) scores (mean differences [MD]: -1.4, p=0.01), were more likely to report intentional weight-loss to improve athletic performance (% difference: 33.0%; p:<.001), and more frequently included resistance training into their training routines (% difference: 21.0%, p=0.01) compared to adolescents. Those with a history of RRIs were more likely to report intentional weight-loss compared to uninjured runners (% difference: 21.3; p=0.02) and had shorter single leg bridge durations than those without RRIs (RRI: 57.9±30, uninjured: 72.0±44, p=0.01).

Conclusion

The findings indicate that addressing aspects of biomechanics identified by the FMS™ and behaviors of weight loss as an effort to improve performance may represent targets for the prevention of RRIs for adult and adolescent runners, given the association with history of RRIs.

Level of Evidence

3.

Running-related injuries in middle school cross-country runners: Prevalence and characteristics of common injuries

BACKGROUND

Understanding the prevalence and factors associated with running-related injuries in middle school runners may guide injury prevention.

OBJECTIVE

To determine the prevalence of running-related injuries and describe factors related to a history of injury.

DESIGN

Retrospective cross-sectional study.

SETTING

Survey distributed online to middle school runners.

METHODS

Participants completed a web-based survey regarding prior running-related injuries, training, sleep, diet, and sport participation.

MAIN OUTCOME MEASUREMENTS

Prevalence and characteristics differentiating girls and boys with and without running-related injury history adjusted for age.

PARTICIPANTS

Youth runners (total: 2113, average age,  13.2 years; boys: n = 1255, girls: n = 858).

RESULTS

Running-related injuries were more prevalent in girls (56% vs. 50%, p = .01). Ankle sprain was the most common injury (girls: 22.5%, boys: 21.6%), followed by patellofemoral pain (20.4% vs. 7.8%) and shin splints (13.6% vs. 5.9%); both were more prevalent in girls (p < .001). Boys more frequently reported plantar fasciitis (5.6% vs. 3.3%, p = .01), iliotibial band syndrome (4.1% vs. 1.4%, p = .001) and Osgood-Schlatter disease (3.8% vs. 1.2%, p = .001). Runners with history of running-related injuries were older, ran greater average weekly mileage, ran faster, had fewer average hours of sleep on weekends, skipped more meals, missed breakfast, and consumed less milk (all p < .05). Girls with history of running-related injuries reported higher dietary restraint scores, later age of menarche, more menstrual cycle disturbances, and higher likelihood of following vegetarian diets and an eating disorder diagnosis (all p < .05). Runners with no history of running-related injuries were more likely to have participated in ≥2 years of soccer or basketball (p < .001).

CONCLUSIONS

Most middle school runners reported a history of running-related injuries and certain injuries differing by gender. Modifiable factors with the greatest association with running-related injuries included training volume, dietary restraint, skipping meals, and less sleep. Sport sampling, including participation in ball sports, may reduce running-related injury risk in this population.

Adolescent Running Biomechanics - Implications for Injury Prevention and Rehabilitation

Global participation in running continues to increase, especially amongst adolescents. Consequently, the number of running-related injuries (RRI) in adolescents is rising. Emerging evidence now suggests that overuse type injuries involving growing bone (e.g., bone stress injuries) and soft tissues (e.g., tendinopathies) predominate in adolescents that participate in running-related sports. Associations between running biomechanics and overuse injuries have been widely studied in adults, however, relatively little research has comparatively targeted running biomechanics in adolescents. Moreover, available literature on injury prevention and rehabilitation for adolescent runners is limited, and there is a tendency to generalize adult literature to adolescent populations despite pertinent considerations regarding growth-related changes unique to these athletes. This perspective article provides commentary and expert opinion surrounding the state of knowledge and future directions for research in adolescent running biomechanics, injury prevention and supplemental training.

Increase in foot arch asymmetry after full marathon completion

Long-distance running results in lowering of the foot medial longitudinal arch, but it is unknown whether the left and right arches decrease equally. This study aimed to determine whether foot arch asymmetry increases upon completion of a full marathon and to identify factors capable of explaining the degree of asymmetry of navicular height and navicular height displacement. The three-dimensional foot posture data of 74 collegiate runners were obtained using an optical foot scanner system before (PRE) and immediately after (POST) a full marathon. The navicular height and arch height ratio (normalised navicular height by foot length) of both feet significantly decreased from PRE to POST full marathon completion (44.3 ± 6.3 mm versus 40.8 ± 6.5 mm, 17.8 ± 2.5 versus 16.6 ± 2.7, respectively; p < 0.001, both). The asymmetry of the arch height ratio was significantly greater POST than PRE marathon. Multiple linear regression analysis indicated that the POST-race Asymmetry Index (AI) of navicular height was significantly predicted by the PRE-race AI of navicular height; navicular height displacement was predicted by PRE-race navicular height and the marathon time. Full marathon running induced increasing asymmetry and lowering of the medial longitudinal arch in runners.

Track distance runners exhibit bilateral differences in the plantar fascia stiffness

Human steady-state locomotion modes are symmetrical, leading to symmetric mechanical function of human feet in general; however, track distance running in a counterclockwise direction exposes the runner’s feet to asymmetrical stress. This may induce asymmetrical adaptation in the runners’ foot arch functions, but this has not been experimentally tested. Here, we show that the plantar fascia (PF), a primary structure of the foot arch elasticity, is stiffer for the left than the right foot as a characteristic of runners, via a cross-sectional study on 10 track distance runners and 10 untrained individuals. Shear wave velocity (index of tissue stiffness: SWV) and thickness of PF and foot dimensions were compared between sides and groups. Runners showed higher PF SWV in their left (9.4 ± 1.0 m/s) than right (8.9 ± 0.9 m/s) feet, whereas untrained individuals showed no bilateral differences (8.5 ± 1.5 m/s and 8.6 ± 1.7 m/s, respectively). Additionally, runners showed higher left to right (L/R) ratio of PF SWV than untrained men (105.1% and 97.7%, respectively). PF thickness and foot dimensions were not significantly different between sides or groups. These results demonstrate stiffer PF in the left feet of runners, which may reflect adaptation to their running-specific training that involves asymmetrical mechanical loading.

Youth running consensus statement: minimising risk of injury and illness in youth runners

Despite the worldwide popularity of running as a sport for children, relatively little is known about its impact on injury and illness. Available studies have focused on adolescent athletes, but these findings may not be applicable to preadolescent and pubescent athletes. To date, there are no evidence or consensus-based guidelines identifying risk factors for injury and illness in youth runners, and current recommendations regarding suitable running distances for youth runners at different ages are opinion based. The International Committee Consensus Work Group convened to evaluate the current science, identify knowledge gaps, categorise risk factors for injury/illness and provide recommendations regarding training, nutrition and participation for youth runners.

Effect of various parameters on Quadriceps angle in adult Indian population

BACKGROUND

The purpose of this study was to compare the values of quadriceps angle (Q angle) in relation to age, weight, height, gender, bilateral and postural variations, and strenuous activities on the weight bearing limbs in order to observe its variability.

MATERIALS AND METHODS

A total of 450 adult healthy volunteers (150 male students, 150 female students and 150 male labourers) were enrolled in this cross sectional study. Each volunteer had its height, weight and Q angles measured. Q angle was measured in all subjects bilaterally in both supine and standing position with the same goniometer. Comparison of Q angles and various parameters and groups were studied and tabulated. Correlation between age, weight, height and Q angles was determined by Karl Pearson's correlation coefficient.

RESULTS

Females had statistically significant higher Q angles in both knees than males of either group, and difference between males of two groups was insignificant. It was more often greater on left side (42.36%) as compared to right, both in males and females. Majority of subjects showed an increase in angle from supine to standing position. There was negative correlation between height and Q angle with both standing and supine position all three groups. Weight and age did not show significant correlation with Q angle. Physical activity did not show any significant effect on the angle.

CONCLUSION

Q angle is an important parameter to assess quadriceps muscle's function and its effect on knee. An increase in the angle is clearly associated with patellofemoral problems. Higher Q angle among females may predispose them to sports related injuries. It is important to take into consideration of such factors like sex, height, posture, side, foot rotation and muscle's relaxation while measuring and comparing the angle.

Forefoot transverse arch height asymmetry is associated with foot injuries in athletes participating in college track events

[Purpose] The association between foot injuries and foot alignment, including the transverse arch height (TAH) and asymmetry, was examined in athletes participating in college track events. [Participants and Methods] This study included 55 male athletes participating in a college track and field club. Data including demographic information and the incidence of foot injuries within a year prior to participation in this study were obtained via questionnaires. TAH and the medial longitudinal arch height during 10 and 90% loading, leg-heel alignment, and the heel angle were measured before calculating the asymmetry of each alignment parameter measured. Participants were categorized into an injury or a normal group. Unpaired t-tests were used to perform between-group comparisons for each alignment parameter measured and asymmetry. Additionally, logistic regression analysis was performed to identify factors associated with foot injuries after adjustment for demographic data. [Results] TAH asymmetry during 10 and 90% loading was significantly greater in the injury group. Further logistic regression analysis performed showed that only TAH asymmetry during 90% loading was significantly associated with foot injuries after adjustment for demographic data. [Conclusion] With regard to track events, a greater asymmetry of forefoot TAH in a weight-bearing position was observed to be associated with foot injuries.

The Epidemiology of Severe Injuries Sustained by National Collegiate Athletic Association Student-Athletes, 2009-2010 Through 2014-2015

CONTEXT

Few researchers have described the incidence of the most severe injuries sustained by student-athletes at the collegiate level.

OBJECTIVE

To describe the epidemiology of severe injuries within 25 National Collegiate Athletic Association (NCAA) sports in the 2009-2010 through 2014-2015 academic years.

DESIGN

Descriptive epidemiology study.

SETTING

Aggregate injury and exposure data from 25 NCAA sports.

PATIENTS OR OTHER PARTICIPANTS

Collegiate student-athletes in the 2009-2010 through 2014-2015 academic years.

MAIN OUTCOME MEASURE(S)

Injury data from the NCAA Injury Surveillance Program were analyzed. A severe injury (1) occurred during a sanctioned competition or practice, (2) required medical attention by an athletic trainer or physician, and (3) resulted in at least 21 days lost from sport activity or a premature end to the sport season. Injury counts, proportions, rates per 1000 athlete-exposures (AEs), rate ratios (RRs), and injury proportion ratios were reported with 95% confidence intervals (CIs).

RESULTS

A total of 3183 severe injuries were reported, for an injury rate of 0.66/1000 AEs. Wrestling had the highest severe injury rate (1.73/1000 AEs), followed by women's gymnastics (1.40/1000 AEs) and football (0.97/1000 AEs). Overall, the severe injury rate was higher in competition than in practice (RR = 4.25, 95% CI = 3.97, 4.56). Most severe injuries were reported during the regular season (69.3%, n = 2206); however, severe injury rates did not differ between the preseason and regular season (RR = 0.98, 95% CI = 0.91, 1.06). Common severely injured body parts were the knee (32.9%, n = 1047), lower leg/ankle/foot (22.5%, n = 715), and head/face/neck (11.2%, n = 358). Common severe injury diagnoses were sprains (32.9%, n = 1048), strains (16.9%, n = 538), and fractures (14.4%, n = 458). Common severe injury mechanisms were player contact (39.3%, n = 1251), noncontact (25.1%, n = 800), and surface contact (12.0%, n = 383).

CONCLUSIONS

Severe injuries occurred across many sports and by numerous mechanisms. By identifying these sport-specific patterns, clinicians' efforts can be tailored toward improving injury-prevention strategies and health outcomes.

Lower limb alignment characteristics are not associated with running injuries in runners: Prospective cohort study

There is conflicting evidence on the association between lower limb alignment characteristics and the incidence of running-related injury (RRI). Therefore, the primary aim of this study was to investigate the association between lower limb alignment characteristics and the incidence proportion of RRI in a convenience sample of recreational runners. A total of 89 recreational runners were included in this prospective cohort study. These participants had been running for at least six months and were injury-free at baseline. Lower limb alignment measurements were conducted in order to calculate lower limb discrepancy, Q-angle, subtalar angle and plantar index. All participants also answered a baseline and biweekly online surveys about their running routine, history of RRI and newly developed RRI over a period of 12 weeks. The prevalence of previous RRI and the 12-week incidence proportion of new RRI were calculated. Logistic regression analysis was performed to estimate the association between lower limb length discrepancy, Q-angle, subtalar angle and plantar ach index with the incidence proportion of RRI. The prevalence of previous RRI was 55.1% (n = 49). The 12-week incidence proportion of new RRI was 27.0% (n = 24). Muscle injuries and tendinopathies were the main types of RRI identified. The lower leg and the knee were the main anatomical regions affected. We did not find significant associations between lower limb length discrepancy, Q-angle, subtalar angle and plantar arch index and injury occurrence.

Consistency of Lower-Body Dimensions Using Surface Landmarks and Simple Measurement Tools

Caia, J, Weiss, LW, Chiu, LZF, Schilling, BK, and Paquette, MR. Consistency of lower-body dimensions using surface landmarks and simple measurement tools. J Strength Cond Res 30(9): 2600-2608, 2016-Body dimensions may influence various types of physical performance. This study was designed to establish the reliability and precision of bilateral lower-body dimensions using surface anatomic landmarks and either sliding calipers or goniometry. Fifty university students (25 men and 25 women) were measured on 2 separate occasions separated by 48 or 72 hours. A small digital caliper was used to acquire longitudinal dimensions of the feet, whereas a larger broad-blade caliper was used to measure lower-limb, hip, and pelvic dimensions. Quadriceps angle (Q-angle) was determined through surface goniometry. Data for all foot and lower-limb dimensions were both reliable and precise (intraclass correlation coefficient (ICC) ≥0.72, SEM 0.1-0.5 cm). Measures of Q-angle were also reliable and precise (ICC ≥0.85, SEM 0.2-0.4°). Findings from this investigation demonstrate that lower-body dimensions may be reliably and precisely measured through simple practical tests, when surface anatomic landmarks and standardized procedures are used. Although intertester reliability remains to be established, meticulous adherence to specific measurement protocols is likely to yield viable output for lower-body dimensions when more sophisticated methods are unavailable or inappropriate.

What are the Differences in Injury Proportions Between Different Populations of Runners? A Systematic Review and Meta-Analysis

BACKGROUND

Many runners suffer from injuries. No information on high-risk populations is available so far though.

OBJECTIVES

The aims of this study were to systematically review injury proportions in different populations of runners and to compare injury locations between these populations.

DATA SOURCES

An electronic search with no date restrictions was conducted up to February 2014 in the PubMed, Embase, SPORTDiscus and Web of Science databases. The search was limited to original articles written in English. The reference lists of the included articles were checked for potentially relevant studies.

STUDY ELIGIBILITY CRITERIA

Studies were eligible when the proportion of running injuries was reported and the participants belonged to one or more homogeneous populations of runners that were clearly described. Study selection was conducted by two independent reviewers, and disagreements were resolved in a consensus meeting.

STUDY APPRAISAL AND SYNTHESIS METHODS

Details of the study design, population of runners, sample size, injury definition, method of injury assessment, number of injuries and injury locations were extracted from the articles. The risk of bias was assessed with a scale consisting of eight items, which was specifically developed for studies focusing on musculoskeletal complaints.

RESULTS

A total of 86 articles were included in this review. Where possible, injury proportions were pooled for each identified population of runners, using a random-effects model. Injury proportions were affected by injury definitions and durations of follow-up. Large differences between populations existed. The number of medical-attention injuries during an event was small for most populations of runners, except for ultra-marathon runners, in which the pooled estimate was 65.6%. Time-loss injury proportions between different populations of runners ranged from 3.2% in cross-country runners to 84.9% in novice runners. Overall, the proportions were highest among short-distance track runners and ultra-marathon runners.

LIMITATIONS

The results were pooled by stratification of studies according to the population, injury definition and follow-up/recall period; however, heterogeneity was high.

CONCLUSIONS

Large differences in injury proportions between different populations of runners existed. Injury proportions were affected by the duration of follow-up. A U-shaped pattern between the running distance and the time-loss injury proportion seemed to exist. Future prospective studies of injury surveillance are highly recommended to take running exposure and censoring into account.

Consequences of single sport specialization in the pediatric and adolescent athlete

Pediatric and adolescent sports participation has increased with a concomitant increase in injuries. Sports have transitioned from recreational to deliberate, structured activities wherein success is determined by achievement of 'elite' status. This has led to specialization in a single sport with intensive, repetitive activity at younger ages causing physical and emotional consequences, particularly true for the growing athlete who is particularly susceptible to injury. Clinicians caring for this population must understand the epidemiology of youth sports specialization, the unique physiology/structure of this age group, and the potential physical and emotional consequences.

What are the main risk factors for running-related injuries?

BACKGROUND

Despite several studies that have been conducted on running injuries, the risk factors for running-related injuries are still not clear in the literature.

OBJECTIVE

The aim of this study was to systematically review prospective cohort studies that investigated the risk factors for running injuries in general.

DATA SOURCES

We conducted electronic searches without restriction of language on EMBASE (1980 to Dec 2012), PUBMED (1946 to Dec 2012), CINAHL (1988 to Dec 2012) SPORTDiscus (1977 to Dec 2012), Latin American and Caribbean Centre on Health Sciences Information (1985 to Dec 2012) and Scientific Electronic Library Online (1998 to Dec 2012) databases, using subject headings, synonyms, relevant terms and variant spellings for each database.

STUDY SELECTION

Only prospective cohort studies investigating the risk factors for running-related musculoskeletal injuries were included in this review. Two independent reviewers screened each article and, if they did not reach a consensus, a third reviewer decided whether or not the article should be included.

STUDY APPRAISAL AND SYNTHESIS METHODS

Year of publication, type of runners, sample size, definition of running-related musculoskeletal injury, baseline characteristics, reported risk factors and the statistical measurement of risk or protection association were extracted from the articles. A scale adapted by the authors evaluated the risk of bias of the articles.

RESULTS

A total of 11 articles were considered eligible in this systematic review. A total of 4,671 pooled participants were analysed and 60 different predictive factors were investigated. The main risk factor reported was previous injury (last 12 months), reported in 5 of the 8 studies that investigated previous injuries as a risk factor. Only one article met the criteria for random selection of the sample and only six articles included a follow-up of 6 months or more. There was no association between gender and running injuries in most of the studies.

LIMITATIONS

It is possible that eligible articles for this review were published in journals that were not indexed in any of the searched databases. We found a great heterogeneity of statistical methods between studies, which prevented us from performing a meta-analysis.

CONCLUSIONS

The main risk factor identified in this review was previous injury in the last 12 months, although many risk factors had been investigated in the literature. Relatively few prospective studies were identified in this review, reducing the overall ability to detect risk factors. This highlights the need for more, well designed prospective studies in order to fully appreciate the risk factors associated with running.

Summer training factors and risk of musculoskeletal injury among high school cross-country runners

STUDY DESIGN

Prospective cohort.

OBJECTIVES

To examine the relationship between summer training practices and risk of injury during the first month of a high school interscholastic cross-country season.

BACKGROUND

Several prospective studies have reported a high incidence of injury in adolescent cross-country runners. However, limited reports exist on the role of summer training practices and risk of injury among these runners.

METHODS

Four hundred twenty-one athletes (186 girls, 235 boys) who competed in interscholastic cross-country were followed during a cross-country season. At the start of the season, all participants completed a questionnaire regarding summer training routines. Time-loss, running-related injuries were tracked during the subsequent season. Logistic regression analysis was used to estimate the odds ratios (ORs) and 95% confidence intervals (CIs) for the risk of initial injury during the first month of the season associated with summer training variables.

RESULTS

Sixty-seven runners (15.9%) had a confirmed injury during the first month of the season, with a higher percent among girls (19.4%) than boys (13.2%) (P = .06). Overall, 60.1% of the participants ran during the summer prior to the season, with a significantly higher percent among girls (71.5%) than boys (51.1%) (P<.0001). Overall, no significant association (OR = 0.9; 95% CI: 0.5, 1.5; P = .90) was found between not running sometime during the preceding summer and increased risk of initial injury during the first month of the season. Among only the runners who ran during the summer, after adjusting for sex and prior injury, first-month injuries were more common among those who did not frequently alternate short and long mileage on different days (OR = 3.0; 95% CI: 1.4, 6.4; P = .005), and/or who ran 8 weeks or fewer (OR = 2.7; 95% CI: 1.2, 5.8; P = .01) during their summer training. Running 8 weeks or fewer (P = .03), not frequently alternating mileage on different days (P = .01), and running a higher percentage of time on predominantly hill (P = .001) and irregular terrains (P = .004) were associated with increased risk of injury for girls.

CONCLUSION

These findings suggest that injuries during the first month of the high school cross-country season may be reduced if runners who participate in summer training activities run a greater number of weeks and frequently vary their daily running mileage during the summer. For girls, training programs that reduce mileage on hills and irregular terrains may help to minimize the occurrence of running-related injury.

LEVEL OF EVIDENCE

Prognosis, level 1b-.

Bilateral assessment of knee muscle relationships in healthy adults

Asymmetric performance of flexor and extensor muscles of the knee may be a risk factor for knee injuries, especially the anterior cruciate ligament. Additionally, asymmetries in power and work may have correlations with fatigue and performance during functional tasks. Among untrained individuals, such asymmetries may be of potential interest for training prescription. Here, we investigated the bilateral performance of knee flexors and extensors muscle groups of untrained individuals. We quantified the torque-angle and torque-velocity relationships, as well as work, power and asymmetry indexes in 20 untrained male (25 ± 4 years old; height 1.74 ± 0.05 m; body mass 76 ± 9 kg). No significant asymmetry was observed for torque-angle and torque-velocity relationships, work and power output for knee flexor and extensor muscle groups (p < .05). Our results suggest that untrained male present symmetry in the knee flexion and extension bilateral performance. Changes in this behavior due to physical training must be monitored.

Patellofemoral pain syndrome

The patellofemoral pain syndrome (PFPS) is a possible cause for anterior knee pain, which predominantly affects young female patients without any structural changes such as increased Q-angle or significant chondral damage. This literature review has shown that PFPS development is probably multifactorial with various functional disorders of the lower extremity. Biomechanical studies described patellar maltracking and dynamic valgus in PFPS patients (functional malalignment). Causes for the dynamic valgus may be decreased strength of the hip abductors or abnormal rear-foot eversion with pes pronatus valgus. PFPS is further associated with vastus medialis/vastus lateralis dysbalance, hamstring tightness or iliotibial tract tightness. The literature provides evidence for a multimodal non-operative therapy concept with short-term use of NSAIDs, short-term use of a medially directed tape and exercise programmes with the inclusion of the lower extremity, and hip and trunk muscles. There is also evidence for the use of patellar braces and foot orthosis. A randomized controlled trial has shown that arthroscopy is not the treatment of choice for treatment of PFPS without any structural changes. Patients with anterior knee pain have to be examined carefully with regard to functional causes for a PFPS. The treatment of PFPS patients is non-operative and should address the functional causes.

LEVEL OF EVIDENCE

V.

Prevention of overuse sports injuries in the young athlete

The purpose of this article is to review the current theories regarding prevalence, mechanism, and prevention strategies for overuse injuries in a young athletic population. This information provides valuable insight into the state of the current evidence regarding overuse injuries in young athletes as well as the potential future directions in the development of overuse injury prevention interventions.

Características das lesões desportivas e fatores associados com lesão em iniciantes de ginástica artística do sexo feminino

A ginástica artística é uma modalidade que combina arte a gestos biomecânicos e tem se destacado entre crianças e adolescentes. Sua prática pode conduzir a lesões desportivas, por isso é importante conhecer os fatores inerentes ao traumatismo para formulação de modelos preventivos. Desse modo, objetivou-se caracterizar as lesões desportivas e verificar os fatores associados com lesão em praticantes de ginástica artística de diferentes níveis de competitividade. Foram entrevistadas 46 ginastas, com média de idade de 10,1±2,0 anos do sexo feminino, classificadas em dois níveis competitivos: iniciação e treinamento. Utilizou-se o inquérito de morbidade referida adaptado com as características da modalidade para reunir dados pessoais, de treinamento e da lesão. Foram observadas 0,3 lesões por atleta e 1,4 lesões por atleta lesionado, em que ginastas da categoria de treinamento apresentaram maior frequência de lesão (83,3%; n=10) do que as de iniciação (10,5%; n=4). Para ambos os níveis, o momento treinamento e a gravidade leve foram os mais relatados. No mecanismo, o sem contato foi mais prevalente na categoria de treinamento (90%; n=9) e o contato direto foi o mais frequente na iniciação (75%; n=3). As variáveis antropométricas e de treinamento foram consideradas fatores associados com lesão para as ginastas. Conclui-se que ginastas da categoria de treinamento possuem maior frequência de lesão. As variáveis antropométricas e de treinamento foram fatores associados com lesão. As características das lesões dependem do nível de competitividade das ginastas.

Does the change in Q angle magnitude in unilateral stance differ when comparing asymptomatic individuals to those with patellofemoral pain?

OBJECTIVE

To determine if Q angle changes in magnitude from bilateral stance when compared to unilateral stance and then if they are significantly different changes related to the presence of patellofemoral joint pain.

DESIGN

Observational correlation.

SETTING

University biomechanics laboratory.

PARTICIPANTS

60 Asymptomatic females and 12 females with patellofemoral joint pain.

MAIN OUTCOME MEASURE

Bilateral and unilateral stance Q angle.

RESULTS

Sixty females had their Q angles measured in bilateral and unilateral stance. Linear regressions showed predictive equations and positive correlations for unilateral and bilateral stance Q angles (r=0.81-0.89, p<0.001). The equations generated were used to predict unilateral Q angle from bilateral Q angle measurements in 12 patients with patellofemoral joint pain. The actual unilateral Q angle measurement of the symptomatic knee was significantly greater than that predicted for each individual (p=0.01), whilst the asymptomatic knee showed no significant difference (p=0.16).

CONCLUSION

This study showed a strong positive relationship between bilateral and unilateral stance Q angles which could be represented in a positive linear regression equation. The linear regression equation was then used to predict the effect on the Q angle of moving from a bilateral to a unilateral stance. It has been found previously that patients with patellofemoral joint pain on loading the limb in unilateral stance in activities such as walking and stair descent have increased knee valgus angle. The current study supports those findings indicating that when taking up unilateral stance patients with patellofemoral joint pain demonstrate greater than expected increase in Q angle which could increase loading on the patellofemoral joint.

Patellofemoral pain: proximal, distal, and local factors, 2nd International Research Retreat

Patellofemoral pain (PFP) is one of the most common lower extremity conditions seen in orthopaedic practice. The mission of the second International Patellofemoral Pain Research Retreat was to bring together scientists and clinicians from around the world who are conducting research aimed at understanding the factors that contribute to the development and, consequently, the treatment of PFP. The format of the 2.5-day retreat included 2 keynote presentations, interspersed with 6 podium and 4 poster sessions. An important element of the retreat was the development of consensus statements that summarized the state of the research in each of the 4 presentation categories. In this supplement, you will find the consensus documents from the meeting, as well as the keynote addresses, schedule, and platform and poster presentation abstracts.

Classification of the height and flexibility of the medial longitudinal arch of the foot

BACKGROUND

The risk of developing injuries during standing work may vary between persons with different foot types. High arched and low arched feet, as well as rigid and flexible feet, are considered to have different injury profiles, while those with normal arches may sustain fewer injuries. However, the cut-off values for maximum values (subtalar position during weight-bearing) and range of motion (ROM) values (difference between subtalar neutral and subtalar resting position in a weight-bearing condition) for the medial longitudinal arch (MLA) are largely unknown. The purpose of this study was to identify cut-off values for maximum values and ROM of the MLA of the foot during static tests and to identify factors influencing foot posture.

METHODS

The participants consisted of 254 volunteers from Central and Northern Denmark (198 m/56 f; age 39.0 ± 11.7 years; BMI 27.3 ± 4.7 kg/m2). Navicular height (NH), longitudinal arch angle (LAA) and Feiss line (FL) were measured for either the left or the right foot in a subtalar neutral position and subtalar resting position. Maximum values and ROM were calculated for each test. The 95% and 68% prediction intervals were used as cut-off limits. Multiple regression analysis was used to detect influencing factors on foot posture.

RESULTS

The 68% cut-off values for maximum MLA values and MLA ROM for NH were 3.6 to 5.5 cm and 0.6 to 1.8 cm, respectively, without taking into account the influence of other variables. Normal maximum LAA values were between 131 and 152° and normal LAA ROM was between -1 and 13°. Normal maximum FL values were between -2.6 and -1.2 cm and normal FL ROM was between -0.1 and 0.9 cm. Results from the multivariate linear regression revealed an association between foot size with FL, LAA, and navicular drop.

CONCLUSIONS

The cut-off values presented in this study can be used to categorize people performing standing work into groups of different foot arch types. The results of this study are important for investigating a possible link between arch height and arch movement and the development of injuries.

Reliability and reference values of two clinical measurements of dynamic and static knee position in healthy children

PURPOSE

The purposes of this study were to evaluate reliability of the Single-limb mini squat test (a dynamic measure of medio-lateral knee position) and the Quadriceps-angle (Q-angle) (a static measure of medio-lateral knee position), present paediatric reference values of the Q-angle, and evaluate the association between the tests.

METHODS

Two hundred and forty-six healthy children (9-16 years) were included (intra/inter-rater reliability for Q-angle (n = 37/85) and for Single-limb mini squat test (n = 33/28)). Dynamic medio-lateral knee position was assessed by the Single-limb mini squat test. Static medio-lateral knee position was evaluated by the Q-angle.

RESULTS

The reliability of the Single-limb mini squat test was found to be moderate (kappa 0.48-0.57, 95% CI 0.16-0.85, 76-79% agreement). Fair to moderate reliability (ICC 0.35-0.42, 95% CI 0.11-0.66, SEM 1.4°-1.9°, n.s.) of the Q-angle measurements was found. Reference values for the Q-angle (mean 13.5° (1.9)-15.3° (2.8)) varies with age and gender. No associations were found between dynamic and static measures.

CONCLUSIONS

The Single-limb mini squat test showed a moderate reliability and the Q-angle showed a fair to moderate reliability. A difference found for age and gender was lower than 5° and may not be clinical significant. No association were found between the two tests, indicating dynamic and static knee position being two different concepts. In a clinical perspective, we suggest that the Single-limb mini squat test is a contribution to the available tool box for evaluation of dynamic medio-lateral knee position in children, although the Q-angle may not be used before more research has been done justifying its use.

Successful rehabilitation of a recreational endurance runner: initial validation for the Bunkie test

This case report details the musculoskeletal evaluation and the successful rehabilitation of a 24-year-old female recreational distance runner who self-referred to physical therapy with an acute bout of low back pain (LBP). Her LBP was provoked during each distance run. The patient's musculoskeletal evaluation revealed core weakness, especially on the left. A recently reported functional test, the Bunkie test, was administered as part of the physical evaluation. The scores from the Bunkie test correlated with other quantitative and qualitative findings. A therapeutic exercise program emphasizing core stabilization was prescribed. The patient was able to shortly return to running pain-free.

The incidence and potential pathomechanics of patellofemoral pain in female athletes

BACKGROUND

The aims of this study were to determine the prevalence and incidence of patellofemoral pain (PFP) in young female athletes and prospectively evaluate measures of frontal plane knee loading during landing to determine their relationship to development of PFP. We hypothesized that increased dynamic knee abduction measured during preseason biomechanical testing would be increased in those who developed PFP relative to teammates who did not develop PFP.

METHODS

Middle and high school female athletes (n=240) were evaluated by a physician for PFP and for landing biomechanics prior to their basketball season. The athletes were monitored for athletic exposures and PFP injury during their competitive seasons.

FINDINGS

At the beginning of the season, the point prevalence of PFP was 16.3 per 100 athletes. The cumulative incidence risk and rate for the development of new unilateral PFP was 9.66 per 100 athletes and 1.09 per 1000 athletic exposures, respectively. All new PFPs developed in middle school athletes who demonstrated mean International Knee Documentation Committee score of 85.6+/-7.7 at diagnosis. The new PFP group demonstrated increased knee abduction moments at initial contact (95% CI: 0.32 to 4.62Nm) on the most-symptomatic limb and maximum (95% CI: 1.3 to 10.1Nm; P=0.02) on the least-symptomatic (or no symptoms) limb relative to the matched control limbs. Knee abduction moments remained increased in the new PFP group when normalized to body mass (P<0.05).

INTERPRETATION

The increased knee abduction landing mechanics in the new PFP group indicate that frontal plane loads contribute to increased incidence of PFP.

Intrarater and interrater reliability of 22 clinical measures associated with lower quarter malalignment

OBJECTIVE

The purpose of this study was to assess the intrarater and interrater reliability of a broad range of techniques commonly used to assess the lower quarter.

METHODS

A test-retest single group design was used to investigate the intrarater and interrater reliability of 22 lower quarter evaluation measures. Two raters conducted each measure twice on a total of 18 unimpaired subjects with an average age of 23.7 years. This study was conducted in the Human Performance Research laboratory in a university setting. Intraclass correlation coefficients were used to assess reliability of continuous variables, and weighted kappa was used to assess nominal or ordinal results.

RESULTS

Side differences were not found (P > .05); thus, data for right and left legs were pooled (n = 36) where applicable. Intraclass correlation coefficient and weighted kappa results ranged from a low of 0.06 to a high of 0.99. Intrarater reliability results were generally higher than interrater reliability results.

CONCLUSION

Many of the clinical measures demonstrated good overall reliability. For those tests where acceptable intrarater and interrater reliability cannot be demonstrated, additional training of raters, modification of the technique, or elimination of the technique's use should be considered.