Epidemiology of Stress Fracture in Police Trainees.

BACKGROUND: Military recruits and athletes have high occurrence of stress fractures, with very high incidence among military recruits. Symptomatic stress fractures can be disabling in some people. This study aims at identifying pattern and distribution of such fractures in Nepal Police trainee and assess the risk factors and demographics that may help to develop the local guidelines. METHODS: This study analysed 65 police trainees who presented to the orthopaedic Out Patient Department at Nepal Police and Province Police Hospital diagnosed as a case of stress fracture from 29 December, 2020 to 29 December, 2021. Ethical approval was obtained and different variables analysed were age, sex, Body Mass Index, location of fracture, duration of pain, method of treatment, time to heal the fracture and time to pain free mobilisation of patient. RESULTS: There were 65 trainees with 86 sites of fracture at different bones with 50.8% (33) of male population. The majority of fracture was located at tibia (58.1%) followed by pubic rami (33.7%) with potentially debilitating fracture neck of femur seen in 4.6% subjects. Mean duration of pain was 20.7±14.2 days with mean time for pain free mobilisation 42.2±17.7 days after presentation. 96.5% of those recovered with conservative treatment (activity restriction or cast). CONCLUSIONS: The location of stress fracture depends upon the type of training or activities. Modification of activities in early phase of training with early visit for medical care in case of trainees with increasing pain may decrease morbidities and complications requiring operative treatment.

Distal Femoral Stress Fractures Has High Operation Rates in Adolescent and Young Adult Athletes.

BACKGROUND: Although stress fractures of the distal femur are rare, symptoms can overlap with other peri-articular knee pathology, delaying diagnosis. Untreated stress fractures have the potential to progress into completed fractures with a higher likelihood for requiring surgery and longer recovery times in otherwise healthy adolescents and young adults. This case series represents the largest cohort of adolescent athletes with distal femoral stress fractures who presented with activity-related knee pain. METHODS: Patients treated nonoperatively and operatively for metaphyseal distal femur stress fractures at a tertiary referral center over a four-year period were retrospectively identified from the medical record. RESULTS: Eight patients (mean age 16.8 y; range 14 to 22 y; 87.5% male; mean body mass index [BMI] 20.9) with a total of 10 distal femur stress fractures were identified. All patients were involved in competitive sports or military training. There was an average of 3.8 encounters with a medical provider between presentation with activity-related knee pain and diagnosis with distal femur stress fracture. All except 1 patient (87.5%) were initially incorrectly diagnosed with another type of peri-articular knee pathology. Six stress fractures (60%) were treated conservatively with protected weight bearing, activity modification, and gradual return to activity. Four completed stress fractures (40%) required operative fixation-3 healed uneventfully, while 1 had an asymptomatic delayed union. Vitamin D insufficiency (<30 ng/mL) was identified in 7 of 8 patients (87.5%) and 3 patients (37.5%) had an underweight BMI (<18.5). The mean clinical follow-up was 13.1 weeks (range, 2.8 to 32.0 wk). CONCLUSIONS: High clinical suspicion for distal femoral stress fractures is needed to avoid misdiagnosis or delayed diagnosis in young, active individuals with activity-related knee pain refractory to conservative management. In this patient population, activity-related knee pain recalcitrant to activity modification, rest, and physical therapy warrants further workup with magnetic resonance imaging and orthopaedic evaluation. Though rare, misdiagnosis can result in catastrophic fractures with prolonged rehabilitation needs. An open line of communication and streamlined access for referral between primary care providers and orthopaedic surgeons is critical in preventing misdiagnosis and delayed treatment. Furthermore, the treatment of concomitant metabolic disorders and nutritional deficiency should not be neglected when treating distal femoral stress fractures. LEVEL OF EVIDENCE: Level-IV (case series).

Injury incidence and prevalence in elite short-course triathletes: a 4-year prospective study.

OBJECTIVE: To characterise the prevalence, incidence rate (IR) and burden of injuries in elite short-course triathletes over a 4-year training and competition period. METHODS: Fifty elite Australian triathletes were prospectively monitored for injury during four consecutive seasons (2018-2021). Injuries requiring medical attention were prospectively recorded and further subcategorised according to time loss. The IR and burden (injury IR×mean injury severity) were calculated per 365 athlete days, with sex differences in IR compared using IR ratios (IRR) from negative binomial regression models. RESULTS: Two hundred and sixty-six injuries were reported in 46 (92.0%) athletes, of which 67.3% resulted in time loss. The injury IR was 1.87 injuries per 365 athlete days (95% CI 1.70 to 2.80), and comparable between sexes (IRR 0.82, 95% CI 0.64 to 1.04, p=0.109). Most injuries (70.7%) were training related. The most frequently injured body sites were the ankle (15.8%), foot (12.4%) and lower leg (12.0%). Bone stress injuries (BSIs) were the most burdensome injury type with 31.38 days of time loss per 365 days (95% CI 24.42 to 38.34). Twenty athletes (40.0%) reported at least one bone stress injury (BSI) (range 0-3). The rate of BSIs in female athletes was three times greater compared with male athletes (IRR 2.99, 95% CI 1.26 to 7.07, p=0.013). CONCLUSION: Two-thirds of injuries reported in elite short-course triathletes resulted in time loss, with the majority occurring during training activities. Foot, ankle and other lower leg injuries had the highest incidence, with BSIs carrying the highest injury burden. The considerably higher rate of BSI observed in female athletes warrants consideration for future prevention strategies in female triathletes.

Epidemiology of bone injuries in elite athletics: A prospective 9-year cohort study.

OBJECTIVES: To describe bone injury patterns in elite track and field athletes. To investigate relationships between bone injury and athlete characteristics to inform future injury prevention strategies. DESIGN: Descriptive epidemiology study. SETTING: Elite athletics training centres across the United Kingdom and internationally, observed between 2012 and 2020. PARTICIPANTS: 207 Olympic programme senior track and field athletes. MAIN OUTCOME MEASURES: Injury number, Incidence, Severity, Burden, Time Loss. RESULTS: There were 78 fractures during the study period. Gradual repetitive bone injuries were the most common type of injury mode. The foot, pelvis and the lumbar spine were the regions with the highest number of bone stress injuries. Stress fractures had a higher burden overall compared to stress reactions. Average return to full training was 67.4 days (±73.1) for stress reactions and 199 (±205.2) days for stress fractures. There was no relationship between bone injury type and age, sex, ethnicity, side dominance or event group. CONCLUSION: Bone stress injuries in athletics have a high severity and burden warranting continued efforts to prevent their occurrence and optimize management. Age, sex, ethnicity, side dominance and event region do not have any relationship with bone injury occurrence and are therefore unlikely to increase risk in this cohort.

Consensus and Equipose in the Management of Military Trainee Femoral Neck Stress Fractures: A Survey of Military Surgeons.

BACKGROUND: Femoral neck stress fractures (FNSFs) are a unique injury pattern not commonly treated in the civilian trauma population; however, it is particularly high with military trainees engaged in basic combat training. To date, no study has surveyed a population of military orthopedic surgeons on treatment preferences for military service members (SMs) with FNSF. QUESTIONS: We aim to evaluate the extent of clinical equipoise that exists in the management of these injuries, hypothesizing that there would be consensus in the factors dictating surgical and non-surgical intervention for FNSF. PATIENTS AND METHODS: A 27-question survey was created and sent to U.S. military orthopedic surgeon members of the Society of Military Orthopaedic Surgeons. The survey was designed in order to gather the experience among surgeons in treating FNSF and identifying variables that play a role in the treatment algorithm for these patients. In addition, seven detailed, clinical vignettes were presented to further inquire on surgeon treatment preferences. Binomial distribution analysis was used to evaluate for common trends within the surgeon's treatment preferences. RESULTS: Seventy orthopedic surgeons completed the survey, the majority of whom were on active duty status in the U.S. Military (82.86%) and having under 5 years of experience (61.43%). Majority of surgeons elected for a multiple screw construct (92.86%), however the orientation of the multiple screws was dependent on whether the fracture was open or closed. Management for compression-sided FNSF involving ≥50% of the femoral neck width, tension-sided FNSF, and stress fractures demonstrating fracture line progression had consensus for operative management. Respondents agreed upon prophylactic fixation of the contralateral hip if the following factors were involved: Complete fracture (98.57%), compression-sided fracture line >75% (88.57%), compression-sided fracture line >50-75% with hip effusion (88.57%), contralateral tension-sided fracture (87.14%), and compression-sided fracture line >50-75% (84.29%). An FNSF < 50% on the contralateral femoral neck or a hip effusion was indeterminate in surgeons indicating need for prophylactic fixation. Majority of surgeons (77.1%) utilized restricted toe-touch weight-bearing for postoperative mobility restrictions. CONCLUSIONS: Consensus exists for surgical and non-surgical management of FNSF by U.S. military orthopedic surgeons, despite the preponderance of surgeons reporting a low annual volume of FNSF cases treated. However, there are certain aspects in the operative and non-operative management of FNSF that are unanimously adhered to. Specifically, our results demonstrate that there is no clear indication on the management of FNSF when an associated hip effusion is involved. Additionally, the indications for surgically treating contralateral FNSF are unclear. LEVEL OF EVIDENCE: IV.

Incidence, risk factors, and complications of acromial stress fractures after reverse total shoulder arthroplasty.

BACKGROUND: An acromial stress fracture (ASF) is an uncommon complication after reverse total shoulder arthroplasty (RTSA) that can have severe clinical consequences on shoulder function. Although patient-specific factors have been identified to influence the risk of ASF, it is unclear whether modifying these factors can minimize risk. Moreover, there is limited information on the treatment outcomes of these fractures. Therefore, the purpose of this study was to determine modifiable risk factors for ASFs and the complication and revision rates of conservatively and operatively managed ASFs. METHODS: The PearlDiver database was queried to identify a cohort of patients who underwent RTSA with minimum 2-year follow-up. Current Procedural Terminology and International Classification of Diseases codes were used to compare the demographic characteristics, comorbidities, and medication use of patients with and without ASFs. Surgical complication and revision rates were compared between operatively and conservatively treated fractures. RESULTS: The overall incidence of ASFs was 1.4%. Patient-specific factors that were independently associated with the occurrence of an ASF included osteoporosis, rheumatologic disease, shoulder corticosteroid injection within 3 months before surgery, and chronic oral corticosteroid use. Among patients with osteoporosis, the initiation of physical therapy within 6 weeks after surgery also increased the risk of ASF. Patients who underwent surgical treatment of ASFs had a revision arthroplasty rate of 7.0% compared to a rate of 3.2% among those with conservatively managed fractures. CONCLUSION: ASFs are infrequent complications that can occur after RTSA. Preoperative factors that affect the quality of bone independently increase the fracture risk. Moreover, this risk can be minimized by avoiding shoulder corticosteroid injections 3 months before surgery and delaying physical therapy exercises among patients with osteoporosis. Surgical fixation of these fractures should be reserved for instances when conservative management has failed given high rates of infection, instability, and revision shoulder arthroplasty.

A Case-Control Analysis of Bone Stress Injury on Advancement and Health Care Utilization in US Air Force Basic Military Trainees.

INTRODUCTION: Every year, approximately 35,000 recruits enter the United States Air Force Basic Military Training (BMT). Musculoskeletal problems are particularly vexing for BMT because a broad array of differentials render definitive diagnosis burdensome and while most sufferers will fully recover, healing often requires protracted training delays resulting in increased unrecoverable training costs to the program. The purpose of this study is to conduct a case-control study of basic military trainees entering service from 2012 to 2015 to assess detectable differences in demographics, retention, and health care utilization. MATERIALS AND METHODS: This is a retrospective case-control study of existing data and records obtained from existing and active information record systems for individuals who attended BMT between the years 2012 and 2015. Cohort assignment was based on incidence of first stress fracture diagnosis (i.e., having a select diagnosis code in one's medical record) relative to arrival at BMT. Health care utilization is operationalized as medical encounter frequencies and associated international classification of disease (ICD) codes occurring for all patients from BMT recruit date of arrival to 6 months post-graduation (i.e., 180 days). RESULTS: The primary dataset includes 132,359 distinct individuals, of which 129,637 (98%) had no history of stress fracture diagnosis and 1,487 (1%) of which have a diagnosis of stress fracture more than 60 days after arrival at BMT; these are assigned to the CONTROL group. There are 1,235 (0.9%) assigned to the CASE group. CASE members presented with 30.1 unique ICD-10 codes post-graduation compared to 6.3 in the CONTROL group. Six of the top thirteen ICD-10 codes were musculoskeletal in nature and all presented significantly higher rates for the CASE group. CONCLUSIONS: Trainees who suffered a bone stress injury (BSI) during the United States Air Force BMT advanced in rank on par with trainees who did not, but BSI sufferers exhibited greater health care utilization than those who did not suffer BSI. The cost to replace a trainee unable to complete BMT is considerable; however, it is also important to consider the reduction in resiliency and readiness to the Department of Defense and the financial burdens from increased health care utilization. The 2-fold increase in BSI presentation in the graduated control group reflects that more needs to be done for all populations to identify better proactive efforts to foundationally support wellness and prevention rather than accept injury as the status quo.

Cumulative Incidence of All-Cause Knee Injury, Concussion, and Stress Fracture among Transgender Patients on Gender-Affirming Hormone Therapy: An Exploratory Retrospective Cohort Study.

Previous research has shown a discrepancy in incidences of knee injuries, stress fractures, and concussions between cisgender men and women. Little is known regarding the incidence of musculoskeletal injuries among patients on gender-affirming hormone therapy (GAHT). This retrospective cohort study examines cumulative incidence of knee injuries, concussions, and stress fracture injuries among transgender patients on GAHT at one health system from 2011-2020. Using relevant ICD-9 and 10 codes, incidences of knee injury, concussion, and stress fracture were calculated. Cohorts included 1971 transgender and 3964 cisgender patients. Transgender patients had significantly higher incidence of all-cause knee injuries over the study period, 109 (5.5%) versus 175 (4.4%) (p < 0.001; OR: 2.14, 95% CI [1.17-3.92]). Subgroup analysis showed significantly higher incidence of knee injuries among cisgender men (5.6%) versus cisgender women (4.1%) (p = 0.042) and among transgender women (6.6%) versus cisgender women (4.1%) (p = 0.005). There were no significant differences between incidences of concussion and stress fracture between groups. This sample showed that patients on GAHT had increased cumulative incidences of all-cause knee injury compared to controls but similar cumulative incidences of concussion and bone-stress injuries. Transgender women on exogenous estrogen had significantly higher cumulative incidences of all-cause knee injuries compared to cisgender women.

Changes in the incidence of stress reactions and fractures among intercollegiate athletes after the COVID-19 pandemic.

PURPOSE: The purpose of this study was to characterize the impact of detraining due to the COVID-19 pandemic on incidence of bony injuries and stress fractures in collegiate athletes. METHODS: A comprehensive collegiate athletic conference injury database was queried for all in-season, sport-related bony injuries (defined as all stress reactions and fractures) that occurred across all sports from January 2016 to June 2021. The bony injury rate per 1000 athlete exposure hours (AEH) was calculated and compared between the immediate post-hiatus season and historic rates from pre-hiatus seasons (2016-2019). Injury characteristics were also compared between the pre- and post-hiatus time periods. RESULTS: A total of 868 bony injuries across 23 sports were identified. The sports with highest overall baseline bony injury rates in historic seasons were women's cross country (0.57 injuries per 1000 AEH) and men's cross country (0.32). Compared to historic pre-hiatus rates, female cross-country runners demonstrated a significantly lower bony injury incidence rate in the post-hiatus season (0.24 vs. 0.57, p = 0.016) while male swimming athletes demonstrated a statistically significant increase in bony injury rate (0.09 vs. 0.01, p = 0.015). The proportion of bony injuries attributed to repetitive trauma increased; while, the proportion of injuries attributed to running decreased between the pre- and post-hiatus seasons. CONCLUSION: Across all sports, there was no consistent trend toward increased rates of bony injury in the immediate post-hiatus season. However, female cross-country runners demonstrated lower rates of bony injury in the post-hiatus season while male swimmers demonstrated higher rates. Furthermore, bony injuries in the post-hiatus season were more likely to be the result of repetitive trauma and less likely to be from running. LEVEL OF EVIDENCE: Level III, retrospective, cross sectional study.

Pelvic insufficiency fractures and pelvic bone metastases after neoadjuvant (chemo)radiotherapy for rectal cancer.

BACKGROUND: Pelvic insufficiency fractures (PIFs) are a late complication of radiotherapy for pelvic malignancies. We evaluated the incidence, radiologic findings, clinical course, and outcome of PIFs in patients treated with neoadjuvant (chemo)radiotherapy ((C)RT) for rectal cancer. MATERIAL AND METHODS: Data of patients diagnosed with rectal cancer from a large teaching hospital treated from 2002 to 2012 were extracted from the Dutch Cancer Registry. All hospital records were reviewed for the diagnosis of PIFs or pelvic bone metastases. An expert radiologist reassessed all imaging procedures of the lower back, abdomen, and pelvis. RESULTS: A total of 513 rectal cancer patients were identified of whom 300 patients (58.5%) were treated with neoadjuvant (C)RT (long- vs. short-course radiotherapy: 91 patients [17.7%] vs. 209 [40.7%], respectively). Twelve PIFs were diagnosed initially according to hospital records and imaging reports of all 513 patients. These 12 patients were treated with neoadjuvant (C)RT. After reassessment of all pelvic imaging procedures done in this patient group (432 patients (84.2%)), 20 additional PIFs were detected in patients treated with neoadjuvant (C)RT, resulting in a 10.7% PIF rate in irradiated patients. One PIF was detected in the group of patients not treated with neoadjuvant (C)RT for rectal cancer. This patient had palliative radiotherapy for prostate cancer and is left out of the analysis. Median follow-up time of 32 PIF patients was 49 months. Median time between start of neoadjuvant (C)RT and diagnosis of PIF was 17 months (IQR 9-28). Overall median survival for patients with PIF was 63.5 months (IQR 44-120). CONCLUSION: PIFs are a relatively common late complication of neoadjuvant (C)RT for rectal cancer but are often missed or misdiagnosed as pelvic bone metastases. The differentiation of PIFs from pelvic bone metastases is important because of a different treatment and disease outcome.

Acute, isolated fractures of the metatarsal bones: an epidemiologic study.

INTRODUCTION: Although metatarsal fractures are common, the significance of previous epidemiologic studies is limited to specific fracture entities, subpopulations, or heterogeneous fracture aetiologies. The aim of the study was to assess the epidemiology of isolated metatarsal fractures in an adult population at a level-1 trauma centre. MATERIALS AND METHODS: Radiological and clinical databases were searched for a five-year period. Eligible were all patients with acute isolated metatarsal fractures over the age of 18 years with radiographs in two planes available. Stress fractures, injuries affecting Lisfranc joint stability, and concomitant injuries to other regions than the metatarsals were excluded. Data collection included general demographics, mechanism of injury, season of the trauma and fracture details. RESULTS: Out of 3259 patients, 642 patients met the inclusion criteria and were included for the analysis. The patients' mean age was 44.5 ± 18.9 years, 50.6% were female. 83.3% suffered an isolated, 16.7% multiple metatarsal fractures. Single metatarsal fractures occurred predominantly at the fifth metatarsal bone (81.3%), their frequency decreased with increasing age, with a seasonal peak during the summer. Patients suffering multiple metatarsal fractures were significantly older (51.6 ± 21.2 vs. 43.0 ± 18.1 years; p < 0.001) and the injury resulted significantly more often from a high-energy trauma (6.7% vs. 23.4%; p < 0.001). Multiple metatarsal fractures occurred evenly throughout all metatarsals but revealed a focus on female population with no seasonal differences. CONCLUSION: Single metatarsal fractures predominantly occurred at the fifth metatarsal bone and showed a seasonal, gender and age dependency. Multiple metatarsal fractures were homogeneously distributed between the different metatarsals with distinct age-dependent gender differences. LEVEL OF EVIDENCE: Level III.

Part II: Risk Factors for Stress Fractures in Female Military Recruits.

INTRODUCTION: Stress fractures (SFx) represent a significant proportion of injuries in military recruits internationally. Stress fractures disproportionately affect female recruits, a disparity that has similarly been consistently demonstrated in female athletes. Stress fractures result in medical morbidity, financial burden, and medical discharge from military service. This review presents current literature regarding SFx risk factors to identify and/or mitigate in this high-risk population. METHODS: A literature review was conducted using PubMed to find relevant articles. We utilized keywords stress fracture, military, recruits, female, risk factors, modifiable, non-modifiable, overuse, nutrition, and/or prevention. Articles older than 10 years (published before 2010) were not considered. Review articles were considered, but if a research article was cited by a review, the research was included directly. Articles with primary military data, members of the military as subjects, especially when female recruits were included, were strongly considered for inclusion in this review. RESULTS: Modifiable risk factors for SFx include nutritional deficiency, especially of iron, vitamin D, and possibly calcium, poor physical fitness, suboptimal training programming for injury development and recovery, load carriage, and military footwear. Non-modifiable risk factors include female sex, greater height, lower weight and body mass index in females but lower or higher weight and body mass index in males, lower body fat percentage, and lower bone mineral density. In addition, menstrual dysfunction, low energy availability, later age at menarche, and iron deficiency pose unique risks to female recruits. Preventive measures include leadership education, programs with recovery considerations, and risk factor screening. CONCLUSION: This review, Part II of a two-part series, guides multidisciplinary management of military recruits, especially females, who are at risk for developing SFx. Unique nuances of the military recruit require specific knowledge to reduce high incidence rates of injury internationally.

Part I: Background and Clinical Considerations for Stress Fractures in Female Military Recruits.

INTRODUCTION: Stress fractures (SFx) represent a significant proportion of musculoskeletal injuries in military recruits internationally. Incidence rates as high as 40% have been reported, varying by country and branch of military cohorts. Tibial SFx are the most common, followed by other lower extremity sites, and are related to the emphasis on running during training. SFx disproportionately affect female recruits, similarly to a disparity demonstrated in female athletes. METHODS: A literature review of articles relevant to our review was conducted using PubMed, utilizing keywords stress fracture, military, recruits, diagnosis, management, treatment, prevention, epidemiology, background, and/or female. Articles older than 10 years old (prior to 2010) were not considered. Review articles were considered, but if a research article was cited by a review, the research was included directly. Articles with primary military data, members of the military as subjects, especially when female recruits were included, were strongly considered for inclusion in this review. RESULTS: SFx can cause medical morbidity and financial burden and can require discharge from military service. SFx management in the military has cost the United States approximately $100 million annually, which may be underestimated due to lost duty hours or medical discharge with resulting compensation. However, SFx incidence rates have been demonstrated to be reducible with concerted efforts in military cohorts. CONCLUSION: This review, Part I of a two-part series, provides updated information for multidisciplinary management of SFx in female military recruits. There are many similarities to management in athletes, but unique nuances of the military recruit require specific knowledge to reduce the high incidence rates of injury.

The prevalence and effect of the sites of pain in female soccer players with medial shin pain.

BACKGROUND: Female soccer players are often diagnosed with medial shin pain, which includes tibial stress fracture, medial tibial stress syndrome, and chronic exertional compartment syndrome. As the possibility of varied sites of pain affecting sports activities has not been fully researched, an urgent discussion and evidence is required. This study investigates the prevalence and effect of sites of pain on the sports activities of female soccer players with medial shin pain. METHODS: A questionnaire survey was conducted for 196 female soccer players with medial shin pain to assess symptom duration, the effect of practice and performance, and sites of pain. The players were classified into three conditions (tibial stress fracture, medial tibial stress syndrome, or medial shin pain with neurological symptoms) and compared based on sites of pain. RESULTS: We observed that medial tibial stress syndrome had a lower impact on performance compared to that of tibial stress fracture and medial shin pain with neurological symptoms. While participants with tibial stress fracture had to suspend practice sessions more frequently, the difference in symptom duration between the classified groups was not statistically significant. The effect of sites of pain on sports activities was not significantly different in participants with medial tibial stress syndrome. CONCLUSIONS: Medial shin pain should be evaluated carefully to differentiate between medial tibial stress syndrome and medial shin pain with neurological symptoms. Restriction of sports activities may help improve the patient's condition early, regardless of the presentation.

Distribution and risk factors for stress fractures in competitive figure skaters and association with acute fractures.

INTRODUCTION: Figure skating combines esthetic components with high impact, technically demanding elements requiring high volume repetitive training. The evidence base for the sport is limited, particularly regarding stress fracture injuries. This study aims to describe the prevalence and anatomical distribution of stress fracture injuries and assess for risk factors, as well as associations with acute fractures. METHODS: An online anonymous retrospective survey of competitive figure skaters was distributed through social media networks and e-mail for completion by skaters from all three disciplines of figure skating. RESULTS: In a sample of 164 skaters from novice to Olympic level, career prevalence of stress fractures was 24.4%, most commonly affecting tibia and ankle. There was statistically significant increased risk of stress fracture in those training ≥12 times/week (33.3% vs. 17.8%; P = 0.028) but no increased risk associated with level or gender of skater. There was a higher prevalence of acute fracture in those with a history of stress fracture (45.0% vs. 21.8%; P = 0.007). CONCLUSIONS: Figure skaters are at a high risk of stress fractures, independent of the level performed at. There is a higher risk in those training more frequently and an association with additional acute fractures. Results advocate education on fracture features and bone health measures to skaters, coaches, and physicians, at all levels of the sport to facilitate early diagnosis and management.

Ultrasound Identifies First Rib Stress Fractures: A Case Series in National Collegiate Athletic Association Division I Athletes.

Isolated first rib stress fractures in athletes are thought to be rare. In this case series, 3 National Collegiate Athletic Association Division I athletes developed isolated first rib stress fractures over the span of 1 year, indicating that these injuries may occur more often than previously understood. These fractures can be easily missed because of the low incidence, lack of clinical suspicion, and vague presentation. Further, radiographs can fail to reveal such fractures. To our knowledge, this is the largest case series of athletes with first rib stress fractures presenting with vague rhomboid interscapular pain. We also demonstrated that ultrasound successfully visualized these injuries; in the hands of an ultrasonographer or clinical provider trained in musculoskeletal ultrasound, this technique offers an advantageous point-of-care screening imaging modality.

High Prevalence of Foot Insufficiency Fractures in Patients With Inflammatory Rheumatic Musculoskeletal Diseases.

OBJECTIVE: To assess the prevalence of foot insufficiency fractures (IF) in patients with rheumatic musculoskeletal disease (RMD) with foot pain. METHODS: In a retrospective design, 1752 magnetic resonance imaging (MRI) scans of consecutive patients presenting with foot pain in 2 time periods between 2016 and 2018 were evaluated. The group with IF was matched with controls with foot pain without IF. Bone mineral density (BMD) was assessed by dual-energy x-ray absorptiometry. Multivariate analyses were performed. RESULTS: A total of 1145 MRI scans of patients (median age 59 yrs, 82.9% female) with an inflammatory (65.4%) and of 607 with no inflammatory (34.6%) RMD (median age 58 yrs, 80.8% female) were available. Most patients had rheumatoid arthritis (RA; 42.2%), and others had psoriatic arthritis (22.4%), axial spondyloarthritis (11.1%), or connective tissue disease (CTD; 7.6%). Foot IF were found in 129 MRI scans of patients (7.5%). There was no difference between time periods. The prevalence of IF was highest in CTD (23%) and RA (11.4%). More patients with an inflammatory than a noninflammatory RMD had IF (9.1% vs 4.1%, respectively; P < 0.001). Using conventional radiography, IF were only detected in 25%. Low BMD and a history of fractures were more frequent in patients with IF than without (42.6% vs 16.2% and 34.9% vs 8.6%, respectively; P < 0.001). CONCLUSION: A high prevalence of foot fractures was found in MRI scans of patients with RMD, many without osteoporosis. MRI was more sensitive than radiographs to detect IF.

The incidence and risk factors for stress fracture following periacetabular osteotomy.

AIMS: The aims of this study were to characterize the incidence and risk factors associated with stress fractures following periacetabular osteotomy, and to determine their effect on osteotomy union. METHODS: We retrospectively reviewed all periacetabular osteotomies (PAOs) performed for developmental dysplasia of the hip (DDH) at one institution over a six-year period between 2012 and 2017. Perioperative factors were recorded, and included demographic and surgical data. Postoperatively, patients were followed for a minimum of one year with anteroposterior and false profile radiographs of the pelvis to monitor for evidence of stress fracture and union of osteotomies. We characterized the incidence and locations of stress fractures, and used univariate and multivariable analysis to identify factors predictive of stress fracture and the association of stress fracture on osteotomy union. RESULTS: A total of 331 patients underwent PAO during the study period with 56 (15.4%) stress fractures: 46 fractures of the retroacetabular posterior column, five cases of ischiopubic stress fracture, and five cases of concurrent ischiopubic and retroacetabular stress fractures. Overall, 86% (48/56) healed without intervention. Univariate analysis revealed that stress fractures occurred more frequently in females (p = 0.040), older patients (mean age 27.6 years (SD 8.4) vs 23.8 (SD 9.0); p = 0.003), and most often with the use of the broad Mast chisel (28.5%; p < 0.001). Multivariable analysis revealed that increasing age (odds ratio (OR) 1.04; 95% CI 1.01 to 1.07; p = 0.028) and use of the broad Mast chisel (OR 5.1 (95% CI 1.3 to 19.0) compared to narrow Ganz chisel; p = 0.038) and surgeon (p = 0.043) were associated with increased risk of stress fracture. Patients with stress fractures were less likely to have healed osteotomies after one-year follow-up (76% vs 96%; p < 0.001). CONCLUSION: Stress fracture of the posterior column may be an under-recognized complication following PAO, and the rate may be influenced by surgical technique. Consideration should be given to using a narrow chisel during the ischial cut to reduce the risk of stress propagation through the posterior column.Cite this article: Bone Joint J 2022;104-B(9):1017-1024.

Risk factors for subchondral insufficiency fracture of the femoral head in renal transplant patients.

INTRODUCTION: Risk factors associated with subchondral insufficiency fracture (SIF) of the femoral head have not been established. The aim of the present study was to determine the incidence and risk factors for SIF of the femoral head following renal transplantation (RT). MATERIALS AND METHODS: We analyzed the cases of 681 RT patients (mean age at surgery: 49.5 ± 13.6 years, 249 women, 432 men) to determine the incidence of SIF. Hip magnetic resonance imaging (MRI) was performed 6 months post-RT. The following potential predictors of SIF were evaluated: (1) patient's condition at RT: bone mineral density (BMD), pre-RT laboratory values including calcium (Ca), phosphorus (P), calcium-phosphorus product (Ca × P), and intact parathyroid hormone; the patient and donor's blood relationship; and mismatching number of human leukocyte antigens (HLAs), and (2) post-RT dosage(s) of steroid(s), the immunosuppressive regimen, and the incidence of acute rejection. RESULTS: SIF was observed in 15 hips (13 patients, 1.9%). We successfully matched 39 patients without SIF. A multivariate logistic regression analysis adjusted for cumulative dosages of steroids, revealed the following were risk factors for SIF: osteoporosis (OR: 11.4, p = 0.046), lumbar BMD (OR: 0.003, p = 0.038), pre-RT serum P (OR 2.68, p = 0.004), and pre-RT serum Ca × P (OR: 1.11, p = 0.005). CONCLUSION: Since osteoporosis, the lumbar BMD, serum P, and serum Ca × P were identified as risk factors for a post-RT SIF, these factors should be evaluated before RT for the prediction of the SIF risk.

Proportion of Navy Recruits Diagnosed With Symptomatic Stress Fractures During Training and Monetary Impact of These Injuries.

BACKGROUND: Lower extremity stress fractures result in lost time from work and sport and incur costs in the military when they occur in service members. Hypovitaminosis D has been identified as key risk factor in these injuries. An estimated 33% to 90% of collegiate and professional athletes have deficient vitamin D levels. Other branches of the United States military have evaluated the risk factors for stress fractures during basic training, including vitamin D deficiency. To the best of our knowledge, a study evaluating the correlation between these injuries and vitamin D deficiency in US Navy recruits and a cost analysis of these injuries has not been performed. Cutbacks in military medical staffing mean more active-duty personnel are being deferred for care to civilian providers. Consequently, data that previously were only pertinent to military medical providers have now expanded to the nonmilitary medical community. QUESTIONS/PURPOSES: We therefore asked: (1) What proportion of US Navy recruits experience symptomatic lower extremity stress fractures, and what proportion of those recruits had hypovitaminosis vitamin D on laboratory testing? (2) What are the rehabilitation costs involved in the treatment of lower extremity stress fractures, including the associated costs of lost training time? (3) Is there a cost difference in the treatment of stress fractures between recruits with lower extremity stress fractures who have vitamin D deficiency and those without vitamin D deficiency? METHODS: We retrospectively evaluated the electronic medical record at Naval Recruit Training Command in Great Lakes, IL, USA, of all active-duty males and females trained from 2009 until 2015. We used ICD-9 and ICD-10 diagnosis codes to identify those diagnosed with symptomatic lower extremity stress fractures. Data collected included geographic region of birth, preexisting vitamin D deficiency, vitamin D level at the time of diagnosis, medical history, BMI, age, sex, self-reported race or ethnicity, hospitalization days, days lost from training, and the number of physical therapy, primary care, and specialty visits. To ascertain the proportion of recruits who developed symptomatic stress fractures, we divided the number of recruits who were diagnosed with a stress fracture by the total number who trained over that span of time, which was 204,774 individuals. During the span of this study, 45% (494 of 1098) of recruits diagnosed with a symptomatic stress fracture were female and 55% (604 of 1098) were male, with a mean ± SD age of 24 ± 4 years. We defined hypovitaminosis D as a vitamin D level lower than 40 ng/mL. Levels less than 40 ng/mL were defined as low normal and levels less than 30 ng/mL as deficient. Vitamin D levels were obtained at the discretion of the individual treating provider without standardization of protocol. Cost was defined as physical therapy visits, primary care visits, orthopaedic visits, diagnostic imaging costs, laboratory costs, hospitalizations, if applicable, and days lost from training. Diagnostic studies and laboratory tests were incorporated as indirect costs into initial and follow-up physical therapy visits. Evaluation and management code fee schedules for initial visits and follow-up visits were used as direct costs. We obtained these data from the Centers for Medicare & Medicaid Services website. Per capita cost was calculated by taking the total cost and dividing it by the study population. Days lost from training is based on a standardized government military salary of recruits to include room and board. RESULTS: We found that 0.5% (1098 of 204,774) of recruits developed a symptomatic lower extremity stress fracture. Of the recruits who had vitamin D levels drawn at the time of stress fracture, 95% (416 of 437 [95% confidence interval (CI) 94% to 98%]; p > 0.99) had hypovitaminosis D (≤ 40 ng/mL) and 82% (360 of 437 [95% CI 79% to 86%]; p > 0.99) had deficient levels (≤ 30 ng/mL) on laboratory testing, when evaluated. The total treatment cost was USD 9506 per recruit. Days lost in training was a median of 56 days (4 to 108) for a per capita cost of USD 5447 per recruit. Recruits with deficient vitamin D levels (levels ≤ 30 ng/mL) incurred more physical therapy treatment costs than did those with low-normal vitamin D levels (levels 31 to 40 ng/mL) (mean difference USD 965 [95% CI 2 to 1928]; p = 0.049). CONCLUSION: The cost of lost training and rehabilitation associated with symptomatic lower extremity stress fractures represents a major financial burden. Screening for and treatment of vitamin D deficiencies before recruit training could offer a cost-effective solution to decreasing the stress fracture risk. Recognition and treatment of these deficiencies has a role beyond the military, as hypovitaminosis and stress fractures are common in collegiate or professional athletes. LEVEL OF EVIDENCE: Level III, prognostic study.