Personality disorders and cause-specific mortality: a nationwide study of 2 million adolescents.

BACKGROUND: Personality disorders are prevalent in 6-10% of the population, but their risk for cause-specific mortality is unclear. The aim of the study was to assess the association between personality disorders diagnosed in late adolescence and all-cause as well as cause-specific (cardiovascular-related, external-related) mortality. METHODS: We performed a longitudinal study on a historical prospective cohort based on nationwide screening prior to recruitment to the Israeli army. The study participants were 16-19-year-old persons who attended the army screening (medical and cognitive, including screening for psychiatric disorders) between 1967 and 2006. Participants were followed from 1967 till 2011. RESULTS: The study included 2 051 606 subjects, of whom 1 229 252 (59.9%) were men and 822 354 (40.1%) were women, mean age 17.36 years. There were 55 508 (4.5%) men and 8237 (1.0%) women diagnosed with personality disorders. The adjusted hazard ratio (HRs) for coronary, stroke, cardiovascular, external-related causes and all-cause mortality among men with personality disorders were 1.34 (1.03-1.74), 1.82 (1.20-2.76), 1.45 (1.23-1.71), 1.41 (1.30-1.53) and 1.44 (1.36-1.51), respectively. The absolute rate difference for all-cause mortality was 56.07 and 13.19 per 105 person-years among men and women, respectively. Among women with personality disorders, the adjusted HRs for external-related causes and all-cause mortality were 2.74 (1.87-4.00) and 2.01 (1.56-2.58). Associations were already evident within 10 years of follow-up. CONCLUSIONS: Personality disorder in late adolescence is associated with increased risk of cardiovascular, external- and all-cause mortality. Increased cardiovascular mortality is evident before the age of 40 years and may point to the importance of lifestyle education already in youth.

Trends in prehospital pain management: two decades of point-of-injury care.

BACKGROUND: Pain control in trauma is an integral part of treatment in combat casualty care. More soldiers injured on the battlefield need analgesics for pain than life-saving interventions (LSIs). Early treatment of pain improves outcomes after injury, while inadequate treatment leads to higher rates of post-traumatic stress disorder (PTSD). OBJECTIVES: To describe the experience of the Israel Defense Forces (IDF) Medical Corps with prehospital use of analgesia. METHODS: All cases documented in the IDF-Trauma Registry between January 1997 and December 2019 were examined. Data collection included analgesia administered, mechanism of injury, wound distribution, and life-saving interventions performed. RESULTS: Of 16,117 patients, 1807 (11.2%) had at least one documented analgesia. Demographics included 91.2% male; median age 21 years. Leading mechanism of injury was penetrating (52.9%). Of injured body regions reported, 46.2% were lower extremity wounds. Most common types of analgesics were morphine (57.2%) and fentanyl (27%). Over the two decades of the study period, types of analgesics given by providers at point of injury (POI) had changed. Fentanyl was introduced in 2013, and by 2019 was given to 39% of patients. Another change was an increase of casualties receiving analgesia from 5-10% until 2010 to 34% by 2019. A total of 824 LSIs were performed on 556 patients (30.8%) receiving analgesia and no adverse events were found in any of the casualties. CONCLUSIONS: Most casualties at POI did not receive any analgesics. The most common analgesics administered were opioids. Over time analgesic administration has gained acceptance and become more commonplace on the battlefield.

Cognitive and physical performance are well preserved following standard blood donation: A noninferiority, randomized clinical trial.

BACKGROUND: A walking blood bank (WBB) refers to the use of fellow combatants for battlefield blood donation. This requires pretesting combatants for infectious diseases and blood type. A fundamental prerequisite for this technique is that the donating soldier will suffer minimal physiological and mental impact. The purpose of the current study is to assess the effect of blood shedding on battlefield performance. METHODS: This is a double-blind randomized control trial. Forty Israel Defense Forces combatants volunteered for the study. Participants underwent baseline evaluation, including repeated measurement of vital signs, cognitive evaluation, physical evaluation, and a strenuous shooting test. Three weeks after the baseline evaluation, subjects were randomized to either blood donation or the control group. For blinding purposes, all subjects underwent venous catheterization for the duration of a blood donation. Repeated vital signs and function evaluation were then performed. RESULTS: Thirty-six patients were available for randomization. Baseline measurements were similar for both groups. Mean strenuous shooting score was 80.5 ± 9.5 for the control group and 82 ± 6.6 for the test group (p = 0.58). No clinically or statistically significant differences were found in tests designed to evaluate cognitive performance or physical functions. Vital signs taken multiple times were also similar between the test and control groups. CONCLUSIONS: Executive, cognitive, and physical functions were well preserved after blood donation. This study supports the hypothesis that a WBB does not decrease donor combat performance. The categorical prohibition of physical exercise following blood donation might need to be reconsidered in both military and civilian populations.

Severe obesity and cardio-metabolic comorbidities: a nationwide study of 2.8 million adolescents.

BACKGROUND: Severe obesity is rising among adolescents, but data on the prevalence of metabolic abnormalities among this group are limited. We assessed the secular trend of severe obesity and its association with major cardio-metabolic morbidities. METHODS: A total of 2,785,227 Israeli adolescents (aged 17.2 ± 0.5 years) who underwent a pre-recruitment medical examination including routine measurements of weight, height and blood pressure between 1967 and 2015 were included. In all, 230,639 adolescents with abnormally excessive BMI were classified into overweight, classes I, II, and III (severe) obesity. Logistic regression was applied to determine the association between BMI groups and prehypertension, high blood pressure and type 2 diabetes (T2DM). RESULTS: There was 45-fold increase in the prevalence of class III obesity during study period. Severe obesity was recorded in 2060 males and 1149 females, in whom nearly 35 and 43% had prehypertension or high blood pressure, respectively. Compared with adolescents with overweight, the odds ratios (ORs) for high blood pressure in classes II and III obesity groups, respectively, were 2.13 (95% CI, 2.04-2.23) and 2.86 (2.60-3.15) in males, and 2.59 (2.43-2.76) and 3.44 (3.04-3.90) in females, whereas the ORs for T2DM were 19.1 (12.3-29.6) and 38.0 (22.6-64.0) in males, and 15.1 (11.4-20.0) and 24.8 (17.2-35.7) in females. Results persisted in extensive sensitivity analyses including a longitudinal follow-up (median: males, 3.4 years; females, 4.9 years). CONCLUSIONS: Severe obesity showed a marked secular increase and was associated with significantly higher risk for abnormal blood pressure and T2DM than lower degrees of obesity, in both males and females.

Challenges in Implementing International Standards for the Field Hospital Emergency Department in a Disaster Zone: The Israeli Experience.

BACKGROUND: Medical response to world disasters has too often been poorly coordinated and nonprofessional. To improve this, several agencies, led by the World Health Organization (WHO), have developed guidelines to provide accreditation for Foreign Medical Teams (FMTs). There are three levels, with the highest known as FMT Type-3 providing outpatient as well as inpatient surgical emergency care in addition to inpatient referral care. In November 2016, the WHO certified the Israel Defense Forces Field Hospital as the first FMT Type-3. OBJECTIVES: The objectives of this article are to describe the challenges in implementing these international standards for the field hospital emergency department in a disaster zone. DISCUSSION: There are general standards for all levels of FMTs, as well as specific requirements for the FMT-3. These include a mechanism of appropriate triage, two operating suites, 40 regular beds, four to six intensive care unit beds, radiology facilities, and various staff specialties. Despite the sophistication of the field hospital, there are many challenges. Logistical challenges include constructing the hospital in a disaster zone and equipment issues. There are staff challenges such as becoming oriented to a new and difficult environment. Patient challenges include cultural differences, language barriers, and issues of follow-up. There are often ethical challenges unique to the disaster zone. CONCLUSION: By presenting the experience and challenges of the first FMT Type-3, we hope that more countries can join this initiative and improve disaster care throughout the world.

Comparison of Two Intraosseous Devices: The NIO Versus the EZ-IO by Novice Users-A Randomized Cross Over Trial.

BACKGROUND: During resuscitation in the field, intraosseous (IO) access may be achieved using a variety of available devices, often attempted by inexperienced users. AIM: We sought to examine the success rate and ease-of-use ratings of an IO device, the NIO® (New Intraosseous Persys Medical, Houston, TX, USA) in comparison to the Arrow® EZ-IO® (Teleflex Medical Research Triangle Park, NC, USA) by novice users. METHODS: We performed a randomized crossover trial. The study model was a porcine hind leg which was cut distally in order to expose the marrow. The Study population was composed of pre-graduate medical students without prior experience in IO use, all designated future field physicians. The students underwent instruction and practiced the use of both devices. After practice completion, each student attempted a single IO insertion with both devices sequentially in randomized fashion. Success was defined as a flow of fluid through the bone marrow after a single IO attempt. Investigators which determined the success rate were blinded to the used device. RESULTS: 50 users (33 males, 17 females) participated in the trial, mean age of 21.7 years (±1). NIO users were successful in 92% (46/50) attempts while EZ-IO user success rate was 88% (44/50). NIO success rates were comparable to those of EZ-IO (p = NS). Results were similar when examining only the initial device used. Median score of ease of use was 4 (5 point Likert scale) in both devices (p = NS). 54% (27/50) of the participants preferred using the EZ-IO over the NIO (p = NS). CONCLUSION: Novice users were equally successful in establishing IO access with the NIO® in comparison to the EZ-IO® in a porcine model.

[BACTERIA WITHOUT BORDERS: A HIGH CARRIAGE RATE OF ANTIBIOTIC-RESISTANT BACTERIA AMONG SYRIAN CHILDREN HOSPITALIZED IN GALILEE MEDICAL CENTER].

INTRODUCTION: As the civil war in Syria enters its fifth year, the Israeli government continues to provide humanitarian aid to Syrian civilians in Israeli hospitals. Many wounded Syrian children are treated at the Galilee Medical Center (GMC). Due to the patients' incomplete medical history and increasing infection rates in Syria, contact isolation and screening cultures for multi-drug resistant bacteria (MDR's) are conducted upon admission for all Syrian children. AIMS: To describe the rate of MDR carriage in Syrian children and compare it to hospitalized Israeli children. METHODS: Prospective collection of screening culture data of Syrian patients admitted to GMC between 6/2013-11/2014 and comparison with Israeli children admitted between 1-3/2014. Extended-spectrum beta- lactamase-producing Enterobateriaceae (ESBL), Vancomycin-resistant Enterococcus (VRE), Carbapenem-resistant Enterobacteriaceae (CRE), and Methicillin-resistant Staphylococcus aureus (MRSA) were considered MDR's. RESULTS: Of 47 pediatric Syrian patients, 41 were severely wounded. MDR's were found in 37 (79%) children; most of the isolates were ESBL+ Escherichia coli. Over half of the ESBL's were resistant to additional antibiotics such as sulfa and quinolones; no resistance to amikacin was found. In comparison, in 6 of 40 (15%) Israeli children, MDR's (all ESBL's) were found (p<0.001). CONCLUSIONS: In hospitalized Syrian children, contact isolation and screening cultures for MDR's have an important role in the prevention of nosocomial transmission and establishment of empiric antimicrobial protocols. In suspected infections in Syrian children, amikacin and carbapenems are the antimicrobials of choice. MDR's are carried to a lesser extent in Israeli children but due to their importance, further largescale research is needed.

Orthopedic Activity in Field Hospitals Following Earthquakes in Nepal and Haiti : Variability in Injuries Encountered and Collaboration with Local Available Resources Drive Optimal Response.

BACKGROUND: Field hospitals have been deployed by the Israel Defense Forces (IDF) Medical Corps in numerous disaster events. Two recent deployments were following earthquakes in Haiti in 2010 and in Nepal in 2015. Despite arrival in similar timetables, the mode of operation was different-independently in Haiti and in collaboration with a local hospital in Nepal. The pathology encountered in the two hospitals and the resultant treatment requirements were significantly different between the two events. The purpose of this study was to analyze these differences and their implications for preparation and planning of future deployments. METHODS: Data were obtained from IDF records and analyzed using SPSS™ software. RESULTS: 1686 patients were treated in Nepal versus 1111 in Haiti. The caseload in Nepal included significantly less earthquake-related injuries (26 vs. 66 %) with 28 % of them sustaining fractures versus 47 % in Haiti. Femoral fractures accounted for 7.9 % of fractures in Nepal versus 26.4 % in Haiti with foot fractures accounting for 23.8 and 6.4 %, respectively. The rate of open fracture was similar at 29.4 % in Nepal and 27.5 % in Haiti. 18.1 % of injured patients in Nepal underwent surgery, and 32.9 % of which was skeletal compared to 32 % surgical cases (58.8 % skeletal) in Haiti. 74.2 % of patients in Nepal and 34.3 % in Haiti were treated for pathology unrelated to the earthquake. CONCLUSIONS: The reasons for the variability in activities between the two hospitals include the magnitude of the disaster, the functionality of the local medical system which was relatively preserved in Nepal and destroyed in Haiti and the mode of operation which was independent in Haiti and collaborative with a functioning local hospital in Nepal. Emergency medical teams (EMTs) may encounter variable caseloads despite similar disaster scenarios. Advance knowledge of the magnitude of the disaster, the functionality of the local medical system, and the collaborative possibilities will help in planning and preparing EMTs to function optimally and appropriately. However, as this information will often be unavailable, EMTs should be capable to adapt to unexpected conditions.

Does practice make perfect? Prospectively comparing effects of 2 amounts of practice on tourniquet use performance.

INTRODUCTION: Although a lifesaving skill, currently, there is no consensus for the required amount of practice in tourniquet use. We compared the effect of 2 amounts of practice on performance of tourniquet use by nonmedical personnel. METHODS: Israeli military recruits without previous medical training underwent their standard tactical first aid course, and their initial performance in use of the Combat Application Tourniquet (CAT; Composite Resources, Rock Hill, SC) was assessed. The educational intervention was to allocate the participants into a monthly tourniquet practice program: either a single-application practice (SAP) group or a triple-application practice (TAP) group. Each group practiced according to its program. After 3 months, the participants' tourniquet use performance was reassessed. Assessments were conducted using the HapMed Leg Tourniquet Trainer (CHI Systems, Fort Washington, PA), a mannequin which measures time and pressure. RESULTS: A total of 151 participants dropped out, leaving 87 in the TAP group and 69 in the SAP group. On initial assessment, the TAP group and the SAP group performed similarly. Both groups improved their performance from the initial to the final assessment. The TAP group improved more than the SAP group in mean application time (faster by 18 vs 8 seconds, respectively; P = .023) and in reducing the proportion of participants who were unable to apply any pressure to the mannequin (less by 18% vs 8%, respectively; P = .009). CONCLUSION: Three applications per monthly practice session were superior to one. This is the first prospective validation of a tourniquet practice program based on objective measurements.

Procedural sedation and analgesia in the emergency room of a field hospital after the Nepal earthquake.

Procedural sedation and analgesia (PSA) should be a priority in the emergency care of injured children. This humanistic approach is particularly important in paediatric victims of disaster, because these patients are prone to psychological distress secondary to the traumatic event. Following the Nepal earthquake, an Israeli field hospital (IFH) was deployed in Kathmandu. We report our experience with PSA in the emergency room (ER) of the IFH. 22 children underwent surgery in the operating room and 10 underwent PSA in the ER by paediatric emergency physicians: 6 had wound debridement, 2 had fracture reduction and 2 had laceration repair. All the procedures were successfully completed in the ER and no patient required intubation or admission to the intensive care unit due to an adverse event. The present study is the first report of the practice of paediatric PSA by non-anaesthesiologists in a field hospital.

Extending a Helping Hand: A Comparison of Israel Defense Forces Medical Corps Humanitarian Aid Field Hospitals.

BACKGROUND: During the past 6 years the Israel Defense Forces Medical Corps (IDF-MC) deployed three humanitarian delegation field hospitals (HDFHs) in disaster zones around the globe: Haiti (2010), the Philippines (2013), and Nepal (2015). OBJECTIVES: To compare the activity of these HDFHs and the characteristics of the patients they served. METHODS: This retrospective study was based on the HDFHs' operation logs and patients medical records. The study population included both the staff who participated and the patients who were treated in any of the three HDFHs. RESULTS: The Philippine HDFH was a "hybrid" type, i.e., it was integrated with a local hospital. Both the Haitian and the Nepali HDFHs were the "stand-alone" type, i.e., were completely autonomic in resources and in function. The Nepali HDFH had a larger staff, departed from Israel 4 hours earlier and was active 7 hours earlier as compared to the Haitian one. In total, 5465 patients, 55% of them female, were treated in the three HDFHs. In Haiti, Nepal and the Philippines, disaster-related injuries accounted for 66%, 26% and 2% of the cases, respectively. Disaster-related injuries presented mainly in the first days of the HDFHs' activity. CONCLUSIONS: The next HDFH should be planned to care for a significant proportion of routine medical illnesses. The IDF-MC continuous learning process will enable future HDFHs to save more lives as we "extend a helping hand" to foreign populations in crisis.

SARS-CoV-2 Epidemic in the Israeli Defense Force-Lessons Learned From Our rt-PCR Screening Policy.

BACKGROUND: During the SARS-CoV-2 pandemic, multiple preventative measures were used to prevent the virus from spreading in the population. The Israeli defense force deployed further means to contain the disease, including putting units in quarantine, physical distancing and using masks, gowns and disinfectants when in contact with suspected patients. METHODS: We used reverse transcriptase-polymerase chain reaction (rt-PCR) tests to screen for patients among asymptomatic soldiers within units participating in civilian aid or in close contact with known patients, using personal protective equipment. Positive results were repeated and followed with serological testing to verify the nature of results. RESULTS: Between April and May 2020, we screened a total of 1,453 soldiers in 13 different units. We found 11 false positive results, leading to unnecessary measures until resolution, and three true positive results (0.2%). All true positive results had unreported symptoms concomitant with SARS-CoV-2 disease. These results led to the resolution of this screening policy. CONCLUSION: Screening asymptomatic army personnel in this setting with rt-PCR test for SARS-CoV-2 is not warranted and leads to unnecessary false positive results. Efforts should be directed at identifying symptomatic patients.

Pediatric ventilation in a disaster: clinical and ethical decision making.

INTRODUCTION: Medical resources may be overwhelmed in a mass disaster situation. Intensive care resources may be limited even further. When the demand for a certain resource, like ventilators, exceeds its availability, caregivers are faced with the task of deciding how to distribute this resource.Ethical dilemmas arise when a practical decision necessitates ranking the importance of several ethical principles. In a disaster area, the greatest good for the greatest number principle and the goal of equal distribution of resources may take priority over the needs of the individual. Nonetheless, regardless of the interventions available, it is a prime goal to keep the patients' comfort and dignity as much as possible. BACKGROUND: In the mass disaster of the Haiti earthquake of January 2010, The Israeli Defense Forces Medical Corps field hospital was one of the first to respond to the call for help of the Haitian people with surgical and intensive care capabilities. It was the only facility able to ventilate children and neonates in the first week after the earthquake, although this ability was relatively limited. SPECIAL ARTICLE: Five case scenarios that we confronted at the pediatric ward of the field hospital are presented: two children with respiratory compromise due to pulmonary infection, one premature baby with respiratory distress syndrome, an asphyxiated neonate, and a baby with severe sepsis of a probable abdominal origin. In normal circumstances all of them would have been ventilated but with limited resources we raised in each case the question of ventilating or not.To help in the evaluation of each case we used a decision-support tool that was previously developed for ventilator allocation during an influenza pandemic. This tool takes into account several factors, including the illness severity, prognosis, and the expected duration of ventilation. CONCLUSIONS: Applying ethical priorities to analyze the decision-making problems leads to the understanding that an individualized approach with an ongoing assessment of the patient condition and the availability of resources, rather than a strict predefined decision rule, will give patients a better chance of survival, and will assist in allocating scarce resources.

Haiti earthquake 2010: a field hospital pediatric perspective.

On January 12 2010, a 7.0-magnitude earthquake struck Haiti. The region had suffered an estimated 316,000 fatalities with approximately 300,000 injured and more than 1 million people who lost their houses. Following the quake, the Israeli Defense Force Medical Corps dispatched a field hospital unit to the capital city, Port au Prince. The hospital had a pediatric division which included pediatric emergency department, pediatric ward and neonatal unit. We elaborate on the various aspects of pediatric treatment that was provided by our hospital. A total of 363 pediatric patients (younger than 18 years) were admitted to our facility during its 10 days of operation. Out of this total, 272 pediatric patients were treated by the pediatric division, 79 (29%) were hospitalized and 57 (21%) required surgery. The pediatric team included seven pediatricians, one pediatric surgeon and six registered nurses. An electronic record and a hard copy file were created for each patient. Fifty-seven percent of the children presented with direct earthquake related injuries. Twelve patients required resuscitation and stabilization and three patients had died. The majority of injuries were orthopedic while infectious diseases accounted for most of the general pediatric diagnoses. In conclusion, operating a field hospital for a population affected by natural disaster is a complex mission. However, pediatric care has its own unique, challenging characteristics.

Comparison of the Effects of Motion and Environment Conditions on Accuracy of Handheld and Finger-Based Pulse Oximeters.

INTRODUCTION: The most common cause of preventable death on the battlefield is significant blood loss, eventually causing decrease in tissue oxygen delivery. Pulse oximeters (POs) are widely used by the Israeli Defense Forces to obtain fast and noninvasive information about peripheral oxygen saturation (SpO2). However, POs are produced by different manufacturers and therefore include different sensors and are based on distinctive algorithms. This makes them susceptible to different errors caused by factors varying from environmental conditions to the severity of injury. The objectives of this study were to compare the reliability of different devices and their accuracy under various conditions. MATERIAL AND METHODS: Six POs underwent performance analysis. The finger-based category included: MightySat by Masimo, Onyx II by Nonin, and CMS50D by Contec. The handheld category comprised: RAD5 by Masimo, 9847 model by Nonin, and 3301 model by BCI. Several environmental and physiological parameters were altered using the ProSim8 simulator by Fluke biomedical, forming unique test cases under which the devices were tested in stationary and motion conditions. RESULTS: All finger-based POs showed higher error rates of PO SpO2 and heart rate measurements in motion conditions, regardless of the manufacturer. However, newer devices in the handheld category were not affected. Results presented in Phase II showed that the SpO2 measurement error in all the devices was affected by pigmentation. However, the CMS50D, considered a low-cost device, had a significantly higher error size than other devices. In the devices that were influenced both by pigmentation and the finger cleanliness factors, the combined detected error size was clinically significant. The pigmentation, ambient light, and finger cleanliness also had a significant effect on the heart rate measurement in the CMS50D model, unlike the handheld devices, which were not affected. During Phase II, neither the Nonin nor the Masimo devices were deemed to have a significant advantage. CONCLUSION: Considering measurement limitations of POs used is extremely important. Use of handheld devices should be favored for use in motion conditions. Technologically advanced and/or recently developed devices should be preferred because of evolving algorithms, which decrease or eliminate the error factors. The "dirty finger" effect on the measurement error cannot be neglected and therefore the action of finger cleaning should be considered part of the treatment protocol.

Medical Challenges in Underground Warfare.

INTRODUCTION: Throughout history, underground systems have served military purposes in both offensive and defensive tactical settings. With the advance of underground mining, combat tactics, and weapon systems, providing medical support in the subterranean battlefield is a constantly growing challenge. This retrospective cohort study describes the Israeli Defense Force (IDF) Medical Corps experience with treating casualties from underground warfare, as recorded in the IDF Trauma Registry. METHODS: A retrospective cohort study of all casualties engaged in underground warfare, between the years 2004-2018. Medical data were extracted from the IDF Trauma Registry and tactical data were obtained from operational reports. An expert committee characterized the most prevalent challenges. Recommendations were based on a literature review and the lessons learned by the IDF experience. RESULTS: During the study period, 26 casualties were injured in the underground terrain. Of casualties, 12 (46%) due to blast injuries, 9 (35%) were due to smoke inhalation, and 5 (19%) due to crushing injuries. All were males, and the average age was 21.6 years. Ten (38%) were killed in action (died before reaching a medical facility). All 16 casualties reaching the hospital survived (Table I). The expert committee divided the most common challenges into three categories-tactical, environmental, and medical. An overview of medical response planning, common injuries, and designated combat casualty care are discussed below. As in all combat casualty care, the focus should be on safety, bleeding control, and rapid evacuation. CONCLUSION: To plan and provide medical support, a thorough understanding of operational planning is essential. This manuscript presents the evolution of underground warfare, tactical and medical implications, environmental hazards, and common casualty care challenges.

Medial tibial stress fracture diagnosis and treatment guidelines.

OBJECTIVES: To validate and make evidence based changes to the Israel Defense Forces medial tibial stress fracture diagnosis and treatment protocol. DESIGN: Prospective cohort study. METHODS: 429 Elite infantry recruits were reviewed for signs and symptoms of medial tibial stress fracture during 14 weeks of basic training. Suspicion of medial tibial stress fracture was based on the presence of pain, tenderness <1/3 the length of the tibia and a positive fulcrum and/or hop test. Recruits with suspected medial tibial stress fractures were initially treated with 10-14 days of rest. Bone scan was performed only when recruits failed to respond to the rest regimen or required immediate diagnosis. RESULTS: 31 Out of 49 recruits with a suspicion of medial tibial stress fracture underwent bone scan, including 8/26 recruits whose symptoms did not resolve after being treated clinically as stress fractures. There was a significantly greater incidence of medial tibial stress fractures when a positive hop test was present in addition to tibial pain and tenderness (p=0.0001), odds ratio 52.04 (95% CL, 2.80-967.74). Medial tibial stress fracture was found to occur when the band of tibial tenderness was ≤10cm in length. Tibial pain scores were not predictive of stress fracture. CONCLUSIONS: This validation study provides the clinician with evidence based guidelines for the clinical diagnosis and treatment of medial stress fractures and their differentiation from shin splints. An initial treatment protocol without the use of imaging was found to be effective in more than two-thirds of the cases.