Risk Factors For Stress Fractures Research Articles

THE RISK FACTORS OF 5TH METATARSAL STRESS FRACTURE IN FOOTBALL PLAYERS

BackgroundNo firm consensus has been established regarding the risk factors for stress fracture of the 5th metatarsal because of a lack of large-scale prospective studies.ObjectiveThe purpose of this study was...

Bone Health in Athletes.

Context:The health of the skeletal system is important for athletes young and old. From the early benefits of exercise on bones to the importance of osteoporosis prevention and treatment, bone health affects the ability to be active throughout life.Evidence Acquisition:PubMed articles dating from 1986 to 2016 were used for the review. Relevant terms such as keywords and section titles of the article were searched and articles identified were reviewed for relevance to this article.Study Design:Clinical review.Level of Evidence:Levels 1 through 4 evidence included.Results:There is strong evidence that exercise benefits bone health at every age and is a critical factor in osteoporosis prevention and treatment. Vitamin D, calcium, and hormones play vital roles in ensuring optimal bone health. When there is an imbalance between exercise and nutrition, as seen in the female athlete triad, bone health is compromised and can lead to bone stress injuries and early osteoporosis. Both of these can lead to morbidity and lost time from training and competition. Thus, early recognition and appropriate treatment of the female athlete triad and other stress fracture risk factors are vital to preventing long-term bone health problems.Conclusion:To optimize bone health, adequate nutrition, appropriate weightbearing exercise, strength training, and adequate calcium and vitamin D are necessary throughout life.

Plantar pressure asymmetry and risk of stress injuries in the foot of young soccer players

BackgroundAsymmetries in the magnitude of plantar pressure are considered a risk factor for stress fracture of the fifth metatarsal in soccer athletes. ObjectiveTo investigate the presence of plantar pressure asymmetries among young soccer athletes. DesignObservational. SettingLaboratory. ParticipantsThirty young adolescents divided into a soccer player group (n = 15) or a matched control group (n = 15). Main outcome measuresMean plantar pressure was determined for seven different regions of the foot. Data were compared between the preferred and non-preferred foot, and between the groups, during barefoot standing on a pressure mat system. ResultsHigher pressure was found in the hallux, 5th metatarsal and medial rearfoot of the non-preferred foot in the young soccer players. These asymmetries were not observed in the control group. Magnitudes of plantar pressure did not differ between the groups. ConclusionYoung soccer players present asymmetries in plantar pressure in the hallux, 5th metatarsal and medial rearfoot, with higher pressure observed in the non-preferred foot.

Non-Cognitive Personality Assessment and Risk of Injuries Among Army Trainees.

Low levels of pre-accession physical fitness and activity are risk factors for stress fractures and other overuse musculoskeletal injuries among military trainees. One dimension in the Tailored Adaptive Personality Assessment System (TAPAS), a non-cognitive personality test given to Army applicants, specifically assesses propensity to engage in physical activity. This dimension may serve as a surrogate measure for activity or fitness. The study examines the associations between TAPAS dimension scores and risk of musculoskeletal injuries. Fifteen TAPAS dimension scores for 15,082 U.S. Army trainees entering military service in 2010 were provided by the U.S. Army Research Institute for Social and Behavioral Sciences. During 2013-2015, the associations between TAPAS dimension scores (as a continuous variable) and injuries in the first 6 months of service were evaluated using logistic regression, with the measure of association being the OR. The TAPAS physical conditioning dimension was associated with musculoskeletal injuries and stress fractures among both men (musculoskeletal injury, OR=0.83, 95% CI=0.79, 0.86; stress fracture, OR=0.68, 95% CI=0.57, 0.80) and women (musculoskeletal injury, OR=0.77, 95% CI=0.70, 0.85; stress fracture, OR=0.60, 95% CI=0.43, 082). No other dimensions were both significantly and consistently associated with either injury. The TAPAS physical conditioning dimension is a strong predictor of musculoskeletal injury and stress fracture among male and female U.S. Army trainees, and may serve as a pre-accession screen for self-reported physical activity.

Epidemiology of Lower Extremity Stress Fractures in the United States Military.

To comprehensively quantify established risk factors for the development of lower extremity stress fractures within a contemporary U.S. military cohort. Using the Defense Medical Epidemiological Database, all U.S. service members diagnosed with tibia/fibula, metatarsal, other bone, femoral neck, and femoral shaft stress fractures were identified based on International Classification of Diseases, 9th Revision, Clinical Modification code from 2009 to 2012. Incidence rates (IRs) and adjusted IRs controlling for sex, race, age, rank, and branch of service were obtained with multivariate Poisson regression analysis. Between 2009 and 2012, 31,758 lower extremity stress fractures occurred among 5,580,875 person-years, for an unadjusted IR of 5.69 per 1,000 person-years. Tibial/fibular (40%) involvement was the most common. Bimodal age distribution revealed that service members under 20 years old (23.06; 95% confidence interval [CI] 22.52, 23.55) or ≥40 (6.86; 95% CI 6.65, 7.07) had greatest risk. Females were at higher risk for total lower extremity (3.11; 95% CI, 3.03, 3.18). White service members were also more at risk than Black service members (p < 0.0001). The majority of stress fractures (77.5%) occurred in junior enlisted service members, with the Army and Marines most at risk. This investigation elucidates several nonmodifiable risk factors for stress fractures in the military and may inform screening measures to reduce this significant source of disability.

The role of adaptive bone formation in the etiology of stress fracture

Stress fractures are common injuries with load-bearing activities. Stress fractures have been reported in the scientific literature for over a century; however, the etiology continues to be investigated with important distinctions made between the contributions of the tissue-level processes of bone remodeling and modeling. In response to novel repetitive loading, increased bone remodeling may serve to replace fatigue-damaged bone while at the same time creating temporary porosity. Much attention has been given to the role of remodeling in the etiology of stress fracture; however, the role of bone modeling has received less attention. Modest increases in modeling, via bone formation on the periosteal surface of long bones in response to mechanical loading, greatly increases the fatigue resistance of bone. Thus, enhancing this adaptive bone formation is a promising target for stress fracture prevention, and a focus on adaptive bone formation may reveal novel risk factors for stress fracture.

Prospective cohort study of the risk factors for stress fractures in Chinese male infantry recruits.

ObjectiveTo determine potential risk factors that could predict stress fractures over an 8-week basic military training in Chinese male infantry recruits.MethodsRecruits from three infantry units enrolled in this prospective study. At baseline, demographic data, personal history of stress fractures, mean duration of weekly exercise and smoking history were recorded on questionnaires and blood samples taken for analysis of bone turnover biomarkers and genetic factors.ResultsOf the 1516 male recruits who volunteered to participate in the study, 1398 recruits provided data for analysis. In total, 189 stress fracture cases were observed (incidence rate: 13.5%) during the 8-week training period. Recruits with stress fractures had a significantly higher incidence of prior fracture history and lower exercise level prior to enrolment compared with those without stress fractures. A significant difference in both allelic frequency and genotypic distribution of the growth differentiation factor 5 (GDF5) gene rs143383 polymorphism was observed between recruits with and without stress fractures. However, no difference in serum bone turnover biomarkers was detected between groups.ConclusionThis prospective, cohort study indicates that fracture history, lower exercise level and GDF5 rs143383 may be predictive risk factors for stress fractures in Chinese male infantry recruits.

Mechanical Risk Factors for Stress Fracture in Elite Runners

Objectives:Bone stress injuries (BSI) are responsible for significant missed competition and training in distance runners. A recent review of our institution’s injury database revealed that one-fifth of NCAA-level runners sustained one or more BSI over a three-year period. While much is known about certain risk factors for stress injury such as the Female Athlete Triad, little is known about biomechanical risk factors including dynamic loading of the foot during running differs between athletes with history of BSI and those without. The aims of this study were: 1) characterize the dynamic loading patterns of elite distance runners during athletic movement, 2) determine the difference in dynamic loading magnitude and location in runners who have history of a BSI compared to non-injured runners and 3) establish a database to be used for follow-up evaluation. We hypothesized that athletes with a history of BSI in the lower extremity apply greater dynamic loads during athletic movements compared to uninjured athletes.Methods:We recruited 40 healthy varsity distance runners (16 females, 24 males) from our institution to participate in the study. Dynamic foot loading data was collected on all athletes using a validated wireless insole pressure measurement system during a series of athletic movements (e.g., walking, running and lateral cutting). Data was collected for contact area, maximum force, peak pressure, maximum mean pressure and force-time integral at each of eleven foot regions during each athletic movement. All force and pressure data were normalized to body weight. Injury history and other potential risk factors of interest were collected by self-report questionnaire and chart review. All BSI occurred as a result of participation of running, diagnosed by a physician and confirmed with advanced imaging. Mean values were calculated for each variable and foot region in each athlete and paired t-tests were performed for injury history comparisons.Results:A total of 23 runners with a history of 1 or more lower extremity BSI (11 females, 12 males), and 17 athletes with no history of BSI (5 females, 12 males) participated. Runners with a history of BSI trended toward greater peak pressures during running activities (p = .13) compared to uninjured controls, and displayed significantly greater peak pressures in the forefoot during cutting movements (p < .05). Further, those with history of BSI in the foot and ankle displayed greater force-time integral in the forefoot during running (p = .06). In the medial forefoot, athletes with history of BSI displayed significantly greater maximum mean pressures during jump takeoff (p < .05), running (p = .05) and cutting (p < .05). We did not observe a difference in foot strike patterns or FAAM Sport scores between injured and uninjured runners. Menstrual irregularities were seen in a majority of female athletes and were not associated with BSI.Conclusion:Our findings suggest that elite runners with a history of BSI exert greater pressures and force-time integral in the forefoot and medial midfoot during running and cutting compared to uninjured athletes. The greater loads in the forefoot and medial midfoot may play a role in the incidence and recurrence of BSI in running athletes. Further study of our athlete cohort will allow elucidation of specific high pressure points in the foot that may place athletes at risk for specific BSI, and allow us to investigate the utility of preventive measures.

Bone Functionality and Division II Male and Female Collegiate Athletes from Multiple Sports

Participation in athletics is a risk factor for stress fracture however athletes are also viewed as icons of health, specifically bone health. Bone adaptation may vary depending on the type of loading; high or low impact sport. Are the tibiae of athletes involved in high impact sports (volleyball and soccer) functionally adapted compared to runners and swimmers? PURPOSE: To determine if Division II collegiate athletes had functionally adapted tibia (sufficient strength relative to body size) and whether functional adaptation can be determined from both the 25% and 50% tibial site. METHODS: No single variable indicates bone strength (Jepsen, 2013) and therefore cortical area (Ct.Ar), cortical bone mineral density (cBMD), moment of inertia (J) and bone strength (Strength-strain Index) were measured in 73 athletes (46 females and 27 males (age: 20.2 ± 1.7 yrs, body fat % 16.9 ± 7.5)) and 19 college student controls (8 females and 11 males (age: 23.3 ± 2.3 yrs, body fat % 21.1 ± 7.7)) using peripheral quantitative computed tomography (pQCT) at 25% and 50% of tibial length. Bone functionality was assessed by plotting bone strength vs loading (body weight x tibial length) and robustness (total area/length) vs loading. Based on the residuals from the regression, an athlete’s individual functionality was determined and two groups were formed (functionally adapted (FA) and under adapted (UA)). Student’s t-test detected differences. RESULTS: Height, weight, % body fat and tibial length were similar between the FA and UA groups. However, the FA female group had stronger (27%), more robust bones (23%), with larger moments of inertia (J) (33%) than the female UA group. Male FA group had similar cortical area and cBMD (P<0.05) as the male UA group but they had more robust (23%) stronger (26%) bones with larger J (32%). Both the 25% and 50% sites resulted in similar FA and UA groups and differences. Interestingly the FA and UA groups were comprised of athletes from all teams yet a majority of swimmers were found in the UA female group. CONCLUSIONS: Bone functional adaptation cannot be determined by anthropometric variables. FA groups had robust tibiae at the 25% and 50% site and larger J, allowing them to withstand the bending and torsional loads in sports. Determining bone functionality using the 25% or 50% site of the tibia yielded similar results.

Collegiate Cross Country Athlete Lower Extremity Stress Fracture Risk Factors

Collegiate Cross Country Athlete Lower Extremity Stress Fracture Risk Factors

Evaluating the Risk of a Fifth Metatarsal Stress Fracture by Measuring the Serum 25-Hydroxyvitamin D Levels.

The fifth metatarsal bone is a common site of stress fractures in soccer athletes. Although several endocrine risk factors for stress fractures have been proposed, the endocrine risks for fifth metatarsal (5-MT) stress fractures have not been evaluated. To evaluate the endocrine risks of fifth metatarsal stress fractures, we conducted a cumulative case-control study. The present study included 37 athletes, of which 18 had a history of a zone 2 or zone 3 fifth metatarsal stress fracture and 19 controls. We analyzed serum 25-hydroxyvitamin D (25-OHD), serum parathyroid hormone (PTH), as well as biochemical markers of bone turnover by univariate or multivariate analyses. Logistic regression analyses adjusted for multiple confounders revealed that insufficient serum 25-OHD levels less than 30 ng/mL (odds ratio [OR], 23.3), higher serum PTH levels (OR, 1.01), or higher serum bone-specific isoform of alkaline phosphatase levels (OR, 1.10) rather than serum tartrate-resistant acid phosphatase 5b were associated with statistically significantly increased odds of 5-MT stress fractures. A postestimation calculation demonstrated that 25-OHD levels of 10 and 20 ng/mL were associated with 5.1 and 2.9 times greater odds for 5-MT stress fractures, respectively. 25-OHD insufficiency was associated with an increased incidence of 5-MT stress fractures. This insight may be useful for intervening to prevent 5-MT stress fractures. Level III, case-control study.

Rib stress fractures in rowers

Rib stress fracture (RSF) is a relatively frequent, severe and well documented overuse injury in elite rowers. The incidence of RSF has been estimated to be approximately 9 %, but prospective studies with rigorous injury surveillance of larger groups of rowers are needed to confirm this. The burden of RSFs lies primarily in the severity as most reported cases needed 6-8 weeks of rest, rehabilitation and gradual return to rowing before a full return was possible. Anecdotal reports of non-union of RSF emphasize the necessity of “playing it safe” regarding a timely, symptom dependent return to training and competition. Since no evidence based therapy is available that can decrease healing times of stress fractures, a RSF can be a season ending injury for an elite rower. Consequently, prevention of RSF is of paramount importance. Effective prevention of sports injuries requires thorough knowledge of incidence and/or prevalence, severity, risk factors and injury mechanisms. Several potential mechanisms of injury have been suggested. The relatively limited data provided in the literature (biomechanics of ergometer rowing) may at best give hints with regards to which of the suggested and rather different mechanisms of injury that are most likely to actually induce detrimental bending forces to the ribs during rowing. The aetiology of RSF has thus been described as multifactorial also referring to the plethora of potential risk factors for stress fractures. The lack of longitudinal investigations of potential risk factors for RSF in rowing necessitates looking at evidence regarding risk factors for stress fractures in general. In particular, the recent research indicating that low energy availability is of great importance to bone health of endurance athletes seems highly relevant for elite rowers – especially lightweight rowers. Future prospective studies with continuous surveillance (i.e. internet based questionnaires) of the prevalence of RSF symptoms could elucidate the true burden of RSF. If such an investigation is combined with base-line and intermittent assessment of potential risk factors for RSF stronger evidence for cause and effect relationships could be generated. This type of information could inform effective prevention strategies in the future. Based on the currently available knowledge from biomechanical studies of ergometer rowing the implementation of dynamic ergometers could be hypothesized to reduce the risk of RSF. Moreover, some of the known risk factors for stress fractures in general might be hypothesized to also contribute to increased bone health and decreased RSF risk in elite rowers.

Hemoglobin is Positively Associated with Bone Strength in Young Adults Entering the Military

Stress fracture incidence is high during initial military training (IMT) with 2-6% of male and 8-21% of female recruits sustaining fractures. Identification and mitigation of risk factors is critical in efforts to preserve the health of military trainees and decrease injury costs. Prior reports indicate that iron deficiency anemia (IDA) is a risk factor for stress fracture in military recruits. The current study aimed to determine whether hemoglobin (Hgb), the iron-containing oxygen transport protein, was associated with bone strength in young adults entering the military. Bone density, geometry, and strength were measured using peripheral quantitative computed tomography at the 4, 14, and 66% tibia sites , and fasted blood samples collected in 165 (n=90 female [Age = 21.4 ± 2.6 y; BMI=23.9 ± 2.7], n=75 male [Age=20.0 ± 2.6 y, BMI=25.1 ± 3.3]) recruits prior to IMT. Hgb was not associated with any trabecular bone parameter including bone strength at the 4% site (r=0.11, p=0.19). However, Hgb was positively correlated with cortical content (r=0.17, p=0.04) at the 14% site and polar stress-strain index, a surrogate measure of bone strength, at the 66% site (r=0.17, p=0.05) even when controlling for sex and body weight. These findings support a potential role of iron status in cortical bone health suggesting it may be involved in suppression of bone resorption or promotion of bone formation, and provides the basis for future research exploring the effects of iron on bone metabolism in young adults. Research supported by: ORISE and USAMRMC.

The Pathophysiology, Diagnosis, and Management of Foot Stress Fractures

Introduction: There is an increasing prevalence of osteoporosis, and with it a rise in the diagnosis of stress fractures. Postmenopausal women are particularly at risk of stress fractures. This review article describes the pathophysiology of foot stress fractures and the latest diagnostic and treatment strategies for these common injuries. Discussion: There are numerous risk factors for stress fractures that have been identified in the literature. Reduced bone mineral density is an independent risk factor for delayed union. Prevention of stress fractures with training periodization and nutritional assessment is essential, especially in females. Diagnosis of stress fractures of the foot is based on history and diagnostic imaging, which include radiographs, ultrasound, therapeutic ultrasound, computed tomography, and bone scans; however, magnetic resonance imaging is still the gold standard. Treatment depends on the bone involved and the risk of nonunion, with high-risk fractures requiring immobilization or surgical intervention. Patients presenting with underlying bone mineral deficiency treated without surgery require a longer period of activity modification. Training rehabilitation protocols are described for those with low-risk stress fractures. Results: A useful algorithm is presented to guide the clinician in the diagnosis and management of such injuries.

Greater Polar Moment of Inertia at the Tibia in Athletes Who Develop Stress Fractures.

Background:Several previous investigations have determined potential risk factors for stress fractures in athletes and military personnel.Purpose:To determine factors associated with the development of stress fractures in female athletes.Study Design:Case-control study; Level of evidence, 3.Methods:A total of 88 female athletes (cross-country, n = 29; soccer, n = 15; swimming, n = 9; track and field, n = 14; volleyball, n = 12; and basketball, n = 9) aged 18 to 24 years were recruited to participate in a longitudinal bone study and had their left distal tibia at the 4%, 20%, and 66% sites scanned by peripheral quantitative computed tomography (pQCT). Patients included 23 athletes who developed stress fractures during the following year (cases). Whole body, hip, and spine scans were obtained using dual-energy x-ray absorptiometry (DXA). Analysis of covariance was used to determine differences in bone parameters between cases and controls after adjusting for height, lower leg length, lean mass, fat mass, and sport.Results:No differences were observed between cases and controls in any of the DXA measurements. Cases had significantly greater unadjusted trabecular bone mineral content (BMC), greater polar moment of inertia (PMI) at the 20% site, and greater cortical BMC at the 66% site; however, after adjusting for covariates, the differences became nonsignificant. When analyses were repeated using all individuals who had ever had a stress fracture as cases (n = 31) and after controlling for covariates, periosteal circumference was greater in the cases than the controls (71.1 ± 0.7 vs 69.4 ± 0.5 mm, respectively; P = .04).Conclusion:A history of stress fractures is associated with larger bones. These findings are important because larger bones were previously reported to be protective against fractures and stress fractures, but study findings indicate that may not always be true. One explanation could be that individuals who sustain stress fractures have greater loading that results in greater periosteal circumference but also results in the development of stress fractures.

Overuse Injuries and Burnout in Youth Sports

Overuse Injuries and Burnout in Youth Sports

Identifying Sex-Specific Risk Factors for Stress Fractures in Adolescent Runners

Adolescent females and males participating in running represent a population at high risk of stress fracture. Few investigators have evaluated risk factors for prospective stress fracture in this population. To better characterize risk factors for and incidence of stress fractures in this population, we collected baseline risk factor data on 748 competitive high school runners (442 girls and 306 boys) using an online survey. We then followed them prospectively for the development of stress fractures for a mean ± SD of 2.3 ± 1.2 total seasons of cross-country and track and field; follow-up data were available for 428 girls and 273 boys. We identified prospective stress fractures in 5.4% of girls (n = 23) and 4.0% of boys (n = 11). Tibial stress fractures were most common in girls, and the metatarsus was most frequently fractured in boys. Multivariate regression identified four independent risk factors for stress fractures in girls: prior fracture, body mass index < 19, late menarche (age menarche ≥15 yr), and previous participation in gymnastics or dance. For boys, prior fracture and increased number of seasons were associated with an increased rate of stress fractures, whereas prior participation in basketball was associated with a decreased risk of stress fractures. Prior fracture represents the most robust predictor of stress fractures in both sexes. Low body mass index, late menarche, and prior participation in gymnastics and dance are identifiable risk factors for stress fractures in girls. Participation in basketball appears protective in boys and may represent a modifiable risk factor for stress fractures. These findings may help guide future translational research and clinical care in the management and prevention of stress fractures in young runners.

Determinants of stress fracture risk in United States Military Academy cadets

BackgroundPrior studies have identified some risk factors for stress fracture in athletes and military recruits. ObjectiveTo determine whether historical factors, physical measures, biochemical variables of skeletal metabolism, genetic factors, bone density (BMD) and bone size could predict risk of stress fracture over 4years in physically fit cadets at the US Military Academy (USMA). MethodsBaseline surveys, assessments of height, weight, scores on the Army Physical Fitness Test, and peripheral BMD were obtained in all cadets (755 men, 136 women), and central BMD in a subset. Blood samples were analyzed for variables of calcium homeostasis, bone turnover, and selected hormones and genetic factors. Stress fractures were adjudicated by review of orthopedic notes and imaging reports. Results5.7% of male and 19.1% of female cadets had at least 1 stress fracture (58% metatarsal and 29% tibial), most within 3months of entry to USMA. In males, risk of stress fracture was higher in those who exercised <7h per week during the prior year (RR 2.31; CI 1.29,4.12), and in those with smaller tibial cortical area (RR 1.12; CI 1.03,1.23), lower tibial bone mineral content (RR 1.11; CI 1.03,1.20) and smaller femoral neck diameter (RR 1.35, CI 1.01, 1.81). In women, higher stress fracture risk was seen in those with shorter time since menarche (RR 1.44 per year; CI 1.19, 1.73) and smaller femoral neck diameter (RR 1.16; CI 1.01, 1.33.). ConclusionAlthough prior physical training in men, length of prior estrogen exposure in women and leg bone dimensions in both genders played a role, the maximum variance explained by all of these factors was below 10%. We conclude these factors play a minor role in the development of stress fractures in physically fit USMA cadets.

Update on stress fractures in female athletes: epidemiology, treatment, and prevention.

Stress fractures are a common type of overuse injury in athletes. Females have unique risk factors such as the female athlete triad that contribute to stress fracture injuries. We review the current literature on risk factors for stress fractures, including the role of sports participation and nutrition factors. Discussion of the management of stress fractures is focused on radiographic criteria and anatomic location and how these contribute to return to play guidelines. We outline the current recommendations for evaluating and treatment of female athlete triad. Technologies that may aid in recovery from a stress fracture including use of anti-gravity treadmills are discussed. Prevention strategies may include early screening of female athlete triad, promoting early participation in activities that improve bone health, nutritional strategies, gait modification, and orthotics.

Paper 16: Risk Factors for Stress Fractures, Orthopaedic Acute and Overuse Injuries in Female Infantry Recruits

Paper 16: Risk Factors for Stress Fractures, Orthopaedic Acute and Overuse Injuries in Female Infantry Recruits