Current concepts in the evaluation and management of stress fractures

Current concept of stress fractures with an additional category of atypical fractures: a perspective review with representative images

Stress fractures have traditionally been classified into three categories: fatigue fractures due to overuse of bone with normal elastic resistance; insufficiency fractures due to everyday physiological stress on fragile bone with poor elastic resistance; and pathologic fractures due to bone weakness involving tumors. The concept of atypical fractures has emerged and is considered a type of stress fracture. However, there has been some inconsistency in interpretation when using the traditional classification of stress fractures, and atypical femoral fractures (AFFs) can potentially be classified into subtypes: "typical" AFFs involving bone turnover suppression due to specific drugs (e.g. bisphosphonates) and fragility fractures of the bowed femoral shaft. In this article, the classification of stress fractures is redefined with the addition of atypical fractures as a fourth category, in which biological activity for fracture healing is absent, to promote consistent understanding and interpretation of clinical conditions involving stress fractures.

Identifying Factors That Contribute to Adolescent Bony Stress Injury in Secondary School Athletes: A Comparative Analysis With a Healthy Athletic Control Group

BACKGROUND

Bony stress injuries (BSIs) are common among adolescents involved in high school sports. A better understanding of factors that contribute to adolescent BSI is needed to target preventative measures.

HYPOTHESIS

Individuals who suffer a BSI will demonstrate significant differences in training methods, sleep, diet, and history of injury compared with a healthy, noninjured control group.

STUDY DESIGN

Descriptive epidemiologic study.

METHODS

Data from the National High School Stress Fracture Registry (NHSSFR), an internet-based adolescent BSI survey, were used to identify variables reported with adolescent (13-18 years of age) BSI. These findings were compared with a survey of 100 (50 males, 50 females) healthy athletic controls to identify significant differences between healthy adolescents and those with BSI.

RESULTS

A total of 346 stress fractures were reported in 314 (206 females, 108 males) athletes within the NHSSFR. Comparison with healthy control participants demonstrated multiple significant findings. In particular, body mass index was significantly lower for patients with BSI injury compared with controls (P < 0.001). Patients slept significantly less than the control group (7.2 vs 7.95 hours; F = 34.41; P < 0.001). Females also slept significantly less hours than males (7.2 vs 7.63 hours; F = 11.02; P < 0.001). Fifty-eight percent of those who reported a BSI did not engage in any weight training. Those with a BSI had significantly higher average stress ratings than control participants (1.67 vs 1.42; P < 0.001), and females also rated their stress levels significantly higher than males (1.8 vs 1.38; P < 0.001). A significant difference between patients with any BSI and control participants existed for history of "shin splints" (Pearson χ² = 28.31; P < 0.001), and females also expressed having shin pain lasting for longer than 4 weeks (Pearson χ² = 8.12; P < 0.001) and more often (Pearson χ² = 5.84; P = 0.02) than males. There was also a significant difference between patients with BSI and control subjects regarding dairy intake (2.25 vs 2.69; F = 6.43; P = 0.01).

CONCLUSION

Findings revealed significant differences between those who reported a BSI relative to healthy athletic adolescents. These differences included body mass index, prior history of shin splints, involvement in weight training, amount of sleep, daily stress, and dairy intake. Preventive measures should be developed to address these areas to reduce the incidence of BSIs in the adolescent population.

Epidemiology and Impact on Performance of Lower Extremity Stress Injuries in Professional Basketball Players

Background:

Professional basketball players in the National Basketball Association (NBA) subject their lower extremities to significant repetitive loading during both regular-season and off-season training. Little is known about the incidence of lower extremity bony stress injuries and their impact on return to play and performance in these athletes.

Hypothesis:

Stress injuries of the lower extremity will have significant impact on performance.

Study Design:

Case series.

Level of Evidence:

Level 4.

Methods:

All bony stress injuries from 2005 to 2015 were identified from the NBA. Number of games missed due to injury and performance statistics were collected from 2 years prior to injury to 2 years after the injury. A linear regression analysis was performed to determine the impact of injury for players who returned to sport.

Results:

A total of 76 lower extremity bony stress injuries involving 75 NBA players (mean age, 25.4 ± 4.1 years) were identified. Fifty-five percent (42/76) involved the foot, and most injuries occurred during the regular season (82.9%, 63/76), with half occurring within the first 6 weeks. Among players who sustained a fifth metatarsal stress fracture, 42.9% were unable to return to professional play. Players who sustained stress injuries had reduced play performance, specifically related to number of games played (P = 0.014) and number of steals per game (P = 0.004). Players who had surgery had significantly better performance at 2 years than those who were managed nonoperatively, independent of the type of injury (β = 4.561; 95% CI, 1.255-7.868).

Conclusion:

Lower extremity bony stress injuries may significantly affect both short- and long-term player performance and career length. Stress injuries result in decreased player performance, and surgical intervention results in improved performance metrics compared with those treated using conservative methods.

Clinical Relevance:

Stress injuries result in decreased player performance, and surgical intervention results in improved performance metrics.

Stress fractures: definition, diagnosis and treatment

Stress fractures were first described in Prussian soldiers by Breithaupt in 1855. They occur as the result of repeatedly making the same movement in a specific region, which can lead to fatigue and imbalance between osteoblast and osteoclast activity, thus favoring bone breakage. In addition, when a particular region of the body is used in the wrong way, a stress fracture can occur even without the occurrence of an excessive number of functional cycles. The objective of this study was to review the most relevant literature of recent years in order to add key information regarding this pathological condition, as an updating article on this topic.

Management of Low Bone Mass in Female Athletes

As female athletic participation has increased, the positive effects of exercise on health have become evident. However, with this growth in sports activity, a set of health problems unique to the female athlete has emerged. The female athlete triad and its components can occur in females of all ages in every sport. The Female Athlete Triad poses serious health risks, both short and long term, to the overall well-being of affected individuals. Sustained low energy availability can impair health, causing many medical complications within the skeletal, endocrine, cardiovascular, reproductive, and central nervous systems. With the surge of females participating in athletics within the past 10 to 15 years, it is both conceivable and likely that the prevalence of this syndrome will continue to grow. Therefore, it is imperative that appropriate screening and diagnostic measures are enacted by a multidisciplinary team of health care providers, counselors, teachers, and dieticians in order to provide the proper care to affected athletes. Initial awareness should take place within the educational confines of elementary and high schools. Screening for female athletes exhibiting risk factors for the triad should also take place at the time of sports physicals. If one component of the triad is identified, the clinician should take the time to effectively workup the other. Treatment for each component of the triad includes both pharmacological and nonpharmacological measures, with emphasis placed upon increased energy availability and overall improved nutritional health. Using this all-encompassing type of approach, sports medicine practitioners should feel empowered to continue to promote the lifelong well-being of female athletes in the years to come.

Female athlete triad and its components: toward improved screening and management

As female athletic participation has increased, the positive effects of exercise on health have become evident. However, with this growth in sports activity, a set of health problems unique to the female athlete has emerged. The female athlete triad as first described in 1992 by the American College of Sports Medicine consisted of disordered eating, amenorrhea, and osteoporosis; the definition was updated in 2007 to include a spectrum of dysfunction related to energy availability, menstrual function, and bone mineral density. For this review, a comprehensive search of databases-MEDLINE In-Process & Other Non-Indexed Citations, MEDLINE, EMBASE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials, and Scopus, from earliest inclusive dates to January 2013-was conducted by an experienced librarian with input from the authors. Controlled vocabulary supplemented with keywords such as female athlete triad, amenorrhea, oligomenorrhea, fracture, osteopenia, osteoporosis, bone disease, anorexia, bulimia, disordered eating, low energy availability was used to search for articles on female athlete triad. Articles addressing the prevalence, screening, and management of the female athlete triad were selected for inclusion in the review. This article reviews the current definitions of the triad components, epidemiology, pathophysiology, and recommended screening and management guidelines. The lack of efficacy of current screening of athletes is highlighted. Low energy availablity, from either dietary restriction or increased expenditure, plays a pivotal role in development of the triad. Athletes involved in "lean sports" (those that emphasize weight categories or aesthetics, such as ballet, gymnastics, or endurance running) are at highest risk. Treatment is centered on restoring energy availability to reverse adverse changes in the metabolic milieu. Prevention and early recognition of triad disorders are crucial to ensure timely intervention. Caregivers and physicians of female athletes must remain vigilant in education, recognition, and treatment of athletes at risk.

The ability of clinical tests to diagnose stress fractures: a systematic review and meta-analysis

STUDY DESIGN

Systematic literature review and meta-analysis.

OBJECTIVES

To evaluate the diagnostic accuracy of clinical tests to identify stress fractures in the lower limb.

BACKGROUND

Stress fractures are a bone-related overuse injury primarily occurring in the lower limb and commonly affecting running athletes and military personnel. Physical examination procedures and clinical tests are suggested for diagnosing stress fractures; however, data on the diagnostic accuracy of these tests have not been investigated through a systematic review of the literature.

METHODS

A systematic review was conducted in 8 electronic databases to identify diagnostic accuracy studies, published between January 1950 and June 2011, that evaluated clinical tests against a radiological diagnosis of lower-limb stress fracture. Retrieved articles were evaluated using the Quality Assessment of Diagnostic Accuracy Studies tool, and a meta-analysis was performed where appropriate.

RESULTS

Nine articles investigating 2 clinical procedures, therapeutic ultrasound (n = 7) and tuning fork testing (n = 2), met the study inclusion criteria. Meta-analysis was used to statistically analyze the data extracted from the ultrasound articles and demonstrated a pooled sensitivity of 64% (95% confidence interval [CI]: 55%, 73%), specificity of 63% (95% CI: 54%, 71%), positive likelihood ratio of 2.1 (95% CI: 1.1, 3.5), and negative likelihood ratio of 0.3 (95% CI: 0.1, 0.9). Tuning fork test data could not be pooled; however, sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio ranged from 35% to 92%, 19% to 83%, 0.6 to 3.0, and 0.4 to 1.6, respectively.

CONCLUSION

The results of this systematic review do not support the specific use of ultrasound or tuning forks as standalone diagnostic tests for lower-limb stress fractures. As the overall diagnostic accuracy of the tests investigated is not strong, based on the calculated likelihood ratios, it is recommended that radiological imaging should continue to be used for the confirmation and diagnosis of stress fractures of the lower limb.

LEVEL OF EVIDENCE

Diagnosis, level 1a-.J Orthop Sports Phys Ther 2012;42(9):760-771, Epub 19 July 2012. doi:10.2519/jospt.2012.4000.

Stress fractures: diagnosis and management in the primary care setting

Stress fracture represents an overuse injury of the bone resulting from excessive repetitive stress. Diagnosis in most cases is based on clinical evaluation. Plain radiographs may show characteristic changes 2 to 4 weeks from onset of symptoms. Increasingly, magnetic resonance imaging is recognized as the study of choice in the evaluation of stress injury of the bone. Most stress fractures at low-risk sites can be managed in the primary care setting with conservative measures. From a primary care perspective, orthopedic or sports medicine consultation is considered for stress fractures at high-risk sites. This article reviews general principles of diagnosis and management of stress fractures in adolescents.

Stress fractures of the base of the metatarsal bones in young trainee ballet dancers

Classical ballet is an art form requiring extraordinary physical activity, characterised by rigorous training. These can lead to many overuse injuries arising from repetitive minor trauma. The purpose of this paper is to report our experience in the diagnosis and treatment of stress fractures at the base of the second and third metatarsal bones in young ballet dancers. We considered 150 trainee ballet dancers from the Ballet Schools of "Teatro Alla Scala" of Milan from 2005 to 2007. Nineteen of them presented with stress fractures of the base of the metatarsal bones. We treated 18 dancers with external shockwave therapy (ESWT) and one with pulsed electromagnetic fields (EMF) and low-intensity ultrasound (US); all patients were recommended rest. In all cases good results were obtained. The best approach to metatarsal stress fractures is to diagnose them early through clinical examination and then through X-ray and MRI. ESWT gave good results, with a relatively short time of rest from the patients' activities and a return to dancing without pain.