Association between availability of direct access to army occupational therapy with return to duty in active-duty soldiers.

BACKGROUND: Upper extremity musculoskeletal injuries are common with active-duty Army Soldiers and result in increased limited duty days. Patient satisfaction and surgery rates improve with direct access to occupational therapy in the civilian community. PURPOSE: Examine the amount of time from initial evaluation following an upper extremity musculoskeletal injury (MSKI) to return to full duty plus occupational therapy (OT) utilization in Army Soldiers. STUDY DESIGN: Retrospective observational. METHODS: Electronic health records and profiles from 18,206 US active-duty Army soldiers with MSKI and OT evaluation between 2017-2018 were examined. Repeated measures generalized estimating equations provided the rate ratios (RRs) for OT healthcare utilization (total number of OT evaluations and treatment visits) by days to first OT evaluation and limited duty profile (total days on profile). RESULTS: Soldiers were on average 32.0 (SD = 8.9) y/o, predominantly senior enlisted (45.7%), white (58.0%), male (81.4%), 10.0 (SD = 8.4) years of service, and high school or less educated (51.3%). There were 22,617 UE MSKIs with an OT evaluation and 4936 UE MSKIs with profiles. Compared with UE MSKIs with an OT evaluation on the same day, there was a significant increase in rates of OT utilization for 1-7 days (RR: 1.4, 95% CI: 1.3, 1.5), 8-14 days (RR: 1.3, 95% CI: 1.2, 1.4), 15-30 days (RR: 1.4, 95% CI: 1.3, 1.5), 31-60 days (RR: 1.5, 95% CI: 1.4, 1.6), and +60 days later (RR: 1.6, 95% CI: 1.5, 1.7). Similar differences in rates for limited duty profiles were found. CONCLUSION: A greater number of days between diagnosis of UE MSKI and OT evaluation results in greater rates of OT utilization and longer temporary profile. Results suggest that earlier intervention by OT may decrease recovery and healthcare utilization of soldiers.

Behavioral Health-related Reasons for Permanent Duty Limitation Profiles in the U.S. Army: Population-Based Data from 2017 to 2019.

INTRODUCTION: When warfighters are unable to fight, they are formally removed from battle through temporary or permanent duty limitation profiles. This study uses a population-based data repository to characterize permanent behavioral health (BH)-related profiles across the army for an identified 2-year period. The absolute risk of a permanent duty limitation for specific BH categories was also examined. MATERIALS AND METHODS: This study utilized a retrospective population-based design to identify all new BH diagnoses across the U.S. Army. Service members identified as having a new BH diagnosis were tracked for 12 months following the diagnosis to determine the recommendation of a permanent duty limitation profile. RESULTS: From 2017 to 2018, 16% (n = 102,440) of service members received a "new" BH diagnosis. Less than 10% (9.5%; n = 9,752) of soldiers diagnosed with a BH disorder were issued a permanent BH-related duty profile within 12 months of the initial diagnosis. The absolute risk of a permanent profile was highest for soldiers diagnosed with a psychotic or delusional disorder (42%; n = 324) followed by dissociative or somatoform disorders (26%; n = 178) and eating disorders (23%; n = 108). CONCLUSIONS: Military regulations dictating medical readiness and retention standards reflect both the standards required for mission readiness and a layer of medical protection for the service member. This study provides important information on the relationship between a new BH diagnosis and the likelihood that a service member will be referred for a retirement evaluation.

Diagnosed Behavioral Health Disorders, Related Duty Limitations, and Return to Duty Time in the U.S. Army: Population-based Data, from 2017 to 2019.

INTRODUCTION: Less than half of service members with a behavioral health (BH) problem seek care. Soldiers may avoid seeking needed care because of concerns related to being placed on a duty-limiting profile and the related medical disclosures that follow. MATERIALS AND METHODS: This study used a retrospective population-based design to identify all new BH diagnoses across the U.S. Army. The relationship between diagnostic category, risk of being issued a duty limitation (profile), and time until return to full duty was also examined. Data were collected from a comprehensive data repository that includes medical and administrative records. Soldiers with a new BH diagnosis were identified from 2017 to 2018. All duty limitation profiles within 12 months of initial diagnosis were identified. RESULTS: Records for 614,107 unique service members were reviewed. This cohort was mostly male, enlisted, unmarried, and White. The mean age was 27.13 years (SD = 8.05). Soldiers with a new BH diagnosis accounted for 16.7% (n = 102,440) of the population. The most common diagnostic category was adjustment disorder (55.7%). About a quarter (23.6%) of soldiers with a new diagnosis were issued a related profile. The mean length of these profiles was 98.55 days (SD = 56.91). Of those with a new diagnosis, sex and race failed to have an effect on the odds of being placed on a profile. Overall, enlisted, unmarried, or younger soldiers had greater odds of being placed on a profile. CONCLUSION: These data provide relevant information for both the service member who seeks care and command teams seeking readiness projections.

Demographic, psychosocial, and physical fitness predictors of successful graduation from U.S. Army Ranger School.

U.S. Army Ranger School is an arduous 64-day leadership training course designed to simulate the stressors of combat. Although physical fitness has been shown to be an important predictor of successful graduation for Ranger School, psychosocial characteristics like self-efficacy and grit have not been examined. The purpose of this study is to identify personal, psychosocial, and fitness characteristics associated with successful completion of Ranger School. This study was a prospective cohort examining the association of baseline characteristics of Ranger School candidates with a primary outcome of graduation success. Multiple logistic regression was performed to determine the contribution of demographics, psychosocial, fitness and training characteristics to graduation success. Out of 958 eligible Ranger Candidates, this study obtained graduation status for 670 students, 270 (40%) of which graduated. Soldiers who graduated were younger, more likely to come from units with a higher proportion of previous Ranger School graduates, had higher self-efficacy and faster 2-mile run times. The results from this study suggest that Ranger students should arrive in optimal physical conditioning. Furthermore, training programs that optimize student self-efficacy and units with a high proportion of successful Ranger graduates may confer advantage for this challenging leadership course.

The Occupational Military Neuromusculoskeletal Injury Matrix.

INTRODUCTION: Neuromusculoskeletal injuries (NMSKIs) are the primary cause of ambulatory visits, lost duty days, and disability discharges in the U.S. Military. Methods for accurately grouping injury diagnoses are required to allow for surveillance and research identifying risk factors and prevention strategies. The CDC method of grouping these diagnoses includes only the S and T codes (Injury, poisoning, and certain other consequences of external causes) from the ICD-10-CM. However, this does not include the majority of the NMSKI depleting soldier readiness; the M (Disease of the musculoskeletal system and connective tissue) and G (Diseases of the nervous system) codes should be included as these also contain injuries. The goal was to develop a new matrix that would comprehensively capture all NMSKIs experienced by military personnel. This paper details the development of the Occupational Military Neuromusculoskeletal Injury (OMNI) Matrix and characterizes the number and rates of active duty U.S. Army injuries as measured by the OMNI compared to other matrices. MATERIALS AND METHODS: A team of researchers including physical therapists, physician assistants, occupational therapists, physicians, and epidemiologists developed the OMNI. The OMNI utilizes the commonly accepted injury definition inclusive of any anatomical complaint resulting in pain or dysfunction and categorizes injuries from the G, M, S, and T codes. The OMNI follows the CDC's matrix structure with three body region levels, each becoming more specific, and adds two levels called Description of the Injury. Additionally, the OMNI categorizes injuries as Injury Type (Acute, Overuse, Either, or Not Applicable), NMSKI-Type (NMSKI, NMSKI that could be caused by occupational/training tasks, and not an NMSKI), and a miscellaneous category that demarks injuries as Superficial, Blood Vessels, and/or Internal Organs. The different grouping methods in the OMNI provide standardization for many possible injury case definitions. The OMNI allows these injury categories to be included/excluded in a standardized fashion to meet the researchers' scientific questions. To enumerate the number of NMSKI that would be captured by the available matrices, the OMNI, the CDC's matrix, and the U.S. Army Public Health Center's (APHC) Taxonomy of Injuries were applied to active duty Army outpatient population data and all incident NMSKI diagnostic codes entered in electronic medical provider encounters for calendar years 2017 and 2018. RESULTS: Using the OMNI resulted in the capture of over 800,000 more injuries than the CDC's matrix and over 200,000 more than the APHC Taxonomy. The NMSKI rate utilizing the OMNI was 193 per 100 soldier-years in 2017 (892,780 NMSKI) compared to 23 per 100 soldier-years for the CDC's matrix, and 141 per 100 soldier-years for the APHC Taxonomy. CONCLUSION: The OMNI provides an updated standardized method of assessing injuries, particularly in occupational military injury research, that can be utilized for Military Performance Division of injury across many countries and still allow for replication of methods and comparison of results. Additionally, the OMNI has the capacity to capture a greater burden of injury beyond what is captured by other available matrices.

Characterization of Limited Duty Neuromusculoskeletal Injuries and Return to Duty Times in the U.S. Army During 2017-2018.

INTRODUCTION: Neuromusculoskeletal injuries (MSKI) are the leading cause of medical encounters, lost or limited duty days, medical evacuations, and disability in the U.S. Army. In the U.S. Army, objective MSKI incidence rate metrics can be determined through medical encounter data (M2SKIs) with International Classification of Diseases (ICD) 9 and ICD 10 codes or through documented limited duty profiles (LDPs) documenting time-loss MSKI (TLMSKI). The purpose of the current study was to characterize the population incidence of TLMSKIs among U.S. Army soldiers. MATERIALS AND METHODS: This study was approved by the Medical Research and Development Command's Institutional Review Board. This was a retrospective population-level study. The U.S. Army's eProfile system was utilized to characterize all LDPs issued during 2017-2018 and to describe the body regions injured and activities associated with these TLMSKIs. RESULTS: The incidence rate of TLMSKIs was found to be 44 and 40 TLMSKI/100 soldier-years for 2017 and 2018, respectively, which is lower than previously published incidence rates using MSKI receiving medical care. Approximately one quarter of the total active duty Army population in 2017 and 2018 recorded limited duty injuries, where those to the ankle/foot region resulted in the most LDPs and those to the knee resulted in the most lost duty days. The majority of all TLMSKIs were associated with fitness training-related activities. CONCLUSION: This descriptive study is the first to present the U.S. Army population rates for MSKIs that result in LDPs, representing key time losses when soldiers cannot participate in their military occupational and physical training tasks. This study utilizes the LDP system to calculate limited duty days instead of attempting to estimate this information from other means. The eProfile system is limited in that it combines body regions such as ankle/foot and does not allow isolation of ankle or foot independently. It is recommended that research and training programs target the identification, development, and validation of effective and scaleable strategies to maximize performance without severely reducing combat effectiveness because of training TLMSKIs.

Sex and Mental Health Disorder Differences Among Military Service Members With Patellofemoral Syndrome.

BACKGROUND: Mental health disorders are associated with persistent knee pain, but the association between these conditions has had little investigation in the military. The purpose of this study was to identify rates of mental health disorders in patients with patellofemoral pain (PFP) and determine differences by sex and whether mental health copresence influences outcomes. METHODS: Eligible patients with a new PFP diagnosis were categorized according to sex and presence of mental health disorders. Outcomes included odds of mental health disorder before/after initial PFP diagnosis based on sex, and knee-related health care use between patients with/without mental health disorders. RESULTS: In 81,832 individuals with PFP (71.1% men; mean age 33; 91.5% active duty), copresence of any mental health disorders was common (18% men; 28% women). Women had more depression and anxiety; men had more post-traumatic stress disorder and substance abuse disorders. Concurrent mental health disorders after initial PFP diagnosis resulted in higher medical costs and odds of a recurrence (OR 1.24; 95% CI 1.20, 1.28; P < .001). CONCLUSION: Mental health disorders are common in military service members seeking care for patellofemoral pain. Differences in prevalence vary by sex, and presence of mental health disorders adversely affected long-term health care outcomes.

Risk factors for injury associated with low, moderate, and high mileage road marching in a U.S. Army infantry brigade.

OBJECTIVES: Road marching is an important physical training activity that prepares soldiers for a common occupational task. Continued exploration of risk factors for road marching-related injuries is needed. This analysis has assessed the association between modifiable characteristics of physical training and injury risk. METHODS: Injuries in the previous 6 months were captured by survey from 831 U.S. Army infantry soldiers. Road marching-related injuries were reported as those attributed to road marching on foot for specified distances while carrying equipment. Frequencies, means, and relative risk ratios (RR) for road marching-related injury with 95% confidence intervals (CI) were calculated. Adjusted odds ratios (OR) and 95% CI were calculated for leading risk factors using multivariable logistic regression. DESIGN: Retrospective cohort study. RESULTS: Half (50%) of reported injuries were attributed to road marching or running. When miles of exposure were considered, injury risk during road marching was higher than during running (RRroad marching/running=1.8, 95% CI: 1.38-2.37). A higher product of road marching distance and weight worn (pound-miles per month) resulted in greater injury risk (RR≥1473 pound-miles/<1472=1.92, 95% CI: 1.17-2.41). Road marching-related injuries were associated with carrying a load >25% of one's body weight (OR>25%/1-20%=2.09, 95% CI: 1.08-4.05), having high occupational lifting demands (OR50-100+lbs/25-50lbs=3.43, 95% CI: 1.50-7.85), road marching ≥5 times per month (OR≥5 times/4 times=2.11, 95% CI: 1.14-3.91), and running <4 miles per week during personal physical training (OR0/≥10 miles/week=3.56, 95% CI: 1.49-8.54, OR1-4/≥10 miles/week=4.14, 95% CI: 1.85-9.25). CONCLUSIONS: Ideally, attempts should be made to decrease the percentage of body weight carried to reduce road marching-related injuries. Since this is not always operationally feasible, reducing the cumulative overloading from both physical training and occupational tasks may help prevent injury.

Heavy Loads and Lifting are Risk Factors for Musculoskeletal Injuries in Deployed Female Soldiers.

The purpose of this prospective cohort study was to investigate physical, occupational, and psychosocial risk factors for musculoskeletal injuries (MSI) in deployed female soldiers. Before deployment, participants completed performance testing and surveys and after deployment an additional survey detailing occupational demands and MSI. Data analyzed found 57/160 (36%) suffered 78 MSI. In unadjusted analyses, these factors increased the relative risk (RR, 95% confidence interval) of injury: wearing an average load >10% body weight (BW) (RR = 2.00, 1.31-4.57), wearing an average load >1 hour (RR = 2.44, 1.30-4.57), heaviest load worn >15% BW (RR = 5.83, 1.51-22.50), wearing a backpack (RR = 1.82, 1.23-2.80), wearing body armor >1 hour (RR = 1.62, 1.002-2.62), lifting objects weighing above 22.68 kg (RR = 1.96, 1.08-3.57), lifting objects one to two times (RR = 1.73, 1.002-2.97), carrying objects >7.62 m (RR = 2.01, 1.19-3.42), and Y Balance composite score <95.23 (RR = 1.71, 1.13-2.60). The best logistic regression model predicting MSI was average load as % BW (odds ratio [OR] = 1.04, 1.01-1.07), heaviest load as % BW (OR = 1.03, 1.01-1.05), average repetitions lifting objects (OR = 1.07, 1.01-1.14), and sit-ups (OR = 0.93, 0.93-0.99). Results indicate that risk of MSI in deployed female soldiers increased with heavier equipment worn and more repetitious lifting, although more performing more sit-ups on the fitness test before deployment reduced the risk.

Current considerations related to physiological differences between the sexes and physical employment standards.

The use of physical employment standards (PES) has helped ensure that workers have the physical attributes necessary to complete their jobs in a safe and efficient manner. However, PES used in the selection processes have not always reflected the critical physical requirements of the job tasks. Women generally have smaller anthropometric stature than men, less muscle mass, and therefore less strength, power, and endurance, particularly in the upper body. Nonetheless, these attributes in themselves are not valid grounds for exclusion from employment in physically demanding occupations. Selection standards based upon size or strength, irrespective of the job requirements, have resulted in the barring of capable women from physically demanding jobs, claims of gender bias, and costly litigations. To ensure all individuals are provided with equal access to employment, accurate characterization of the critical physical requirements of the job is paramount. This paper summarizes the existing research related to disparities between the sexes that contribute to sex differences in job performance in physically demanding occupations including physical and legal factors. Strategies for mitigating these differences in the setting of PES and the meeting of minimum employment standards are discussed. Where available, injury rates for women and men in physically demanding occupations are presented and the etiology considered. Finally, areas for further research are identified.

A history of low back pain affects pelvis and trunk coordination during a sustained manual materials handling task.

PURPOSE: The purpose of this study was to compare the coordination between the trunk and the pelvis during a sustained asymmetric repetitive lifting task between a group with a history of low back pain (LBP; HBP) and a group with no history of LBP (NBP). METHODS: Volunteers lifted a 11-kg box from ankle height in front to a shelf 45° off-center at waist height, and lowered it to the start position at 12 cycles/min for 10 min. Lifting side was alternated during the trial. Continuous relative phase was used to calculate coordination between the pelvis and trunk rotation at the beginning (Min 1), middle (Min 5), and end of the bout (Min 9). RESULTS: While there were no main effects for group, a significant interaction between time and group indicated that, in the frontal plane, the NBP group coordination was more anti-phase toward the end of the bout, with no such differences for the HBP group. Analysis of sagittal-axial (bend and twist) coordination revealed the HBP group coordination was more in-phase at the end of the bout over the entire cycle and for the lifting phase alone, with no such differences for the NBP group. CONCLUSION: Differences between groups demonstrate residual consequences of LBP in an occupational scenario, even though the HBP group was pain-free for >6 months prior to data collection. More in-phase coordination in the HBP group may represent a coordination pattern analogous to "guarded gait" which has been observed in other studies, and may lend insight as to why these individuals are at increased risk for re-injury.

Description of musculoskeletal injuries occurring in female soldiers deployed to Afghanistan.

Each year musculoskeletal injuries (MSIs) result in thousands of lost duty days and medical discharges. Women represent 15% of the Army and have higher incidence of injury than male soldiers; studies that have investigated MSIs in deployed women are lacking. Therefore, the purpose of this prospective cohort study was to investigate MSIs in women during a 9-month deployment to Afghanistan. Participants were recruited from three Brigade Combat Teams. Participants completed a demographic survey before deployment and a second survey on occupational demands and MSIs after deployment. Of the 160 women, 57 (36%) suffered 78 MSIs resulting in 1,642 days of limited duty, a median of 7 days per MSI, losing 10% of the available duty time to MSIs. Most injuries affected the knee (24%) or low back (18%). Soldiers attributed the majority of injuries (27%) to physical training and trips/falls (17%). Of the MSIs, 93% caused limitations to physical training and 76% resulted in large limitations to occupational tasks. Most MSIs (41%) resolved within 3 weeks and most (37%) occurred before the fourth month of deployment. Prevention measures should target knee and low back injuries. Physical training should be further investigated to discover modifications capable of reducing injuries.

A description of injuries in men and women while serving in Afghanistan.

Musculoskeletal injuries (MSIs) are the most common cause of ambulatory visits in the deployed setting. Research done on deployed populations have focused mostly on men. The purpose of this retrospective cohort study was to describe physical demands and MSIs among male and female soldiers in a Brigade Combat Team during a 12-month deployment to Afghanistan. Data on occupational tasks and injuries were collected from the infantry and brigade support battalions. Out of 57 women, 22 had MSIs (39%) and for the 536 men, 120 (22%) had MSIs resulting in limited duty. The average limited duty was 7.5 and 13 days/injury for women and men, respectively. The most commonly injured body region for the men was the low back (32%) and the low back (22%) and foot and ankle (22%) for women. The activity associated with MSI for women was physical training (25%) and for men it was contact with the enemy (23%). Physically demanding duties, more distance walked, and heavier average load and objects lifted all increased the risk of injury in women. Only lifting heavier weights increased the risk in men. The women appear to have less tolerance to physically demanding work such than their male counterparts.

Physical training risk factors for musculoskeletal injury in female soldiers.

Musculoskeletal injuries (MSIs) result in the most medical encounters, lost duty days, and permanent disability. Women are at greater risk of injury than men and physical training is the leading cause of injury. The purpose of this study was to investigate the demographic, body composition, fitness, and physical training risk factors for injuries in female Soldiers serving in garrison Army units over the past 12 months. Self-report survey was collected from 625 women. The ankle was the most frequently injured body region, 13%. Running was the activity most often associated with injury, 34%. In univariate analysis lower rank, older age, history of deployment, no unit runs, weekly frequency of personal resistance training, and history of injury were all associated with injury. In multivariate analysis rank, history of injury, weekly frequency of unit runs, and weekly frequency of personal resistance training were the best combination of predictors of injury. Running once or twice a week with the unit protected against MSIs, whereas participating in personal resistance training sessions once or twice a week increased the risk of MSIs. With more emphasis on running and resistance training, the U.S. Army could reduce injuries and save billions of dollars in training and health care costs.

Preliminary validation of the military low back pain questionnaire.

Soldiers must perform a variety of physical tasks that the civilian population does not. The Modified Oswestry Disability Index (M-ODI) is the most widely used measure of function in patients with low back pain but does not include military tasks. The Military Low Back Pain Questionnaire (MBQ) was developed by military Physical Therapists to include tasks such as wearing body armor. The purpose of this study was to provide preliminary evidence for the reliability, responsiveness, and validity of the MBQ in nondeployed Soldiers. The MBQ had good reliability compared to the M-ODI. The inter-rater correlation coefficient for the M-ODI was 0.79 and 0.75 for the MBQ. Cronbach's alpha was 0.75 and 0.85 for the M-ODI and MBQ, respectively. The minimal detectable change for the M-ODI was 21.03 and 22.97 for the MBQ. Responsiveness was assessed using a global rating of change; area under the curve for the M-ODI was 0.82 and 0.90 for the MBQ. The correlation between the M-ODI and the MBQ was r = 0.80 indicating good concurrent validity. The MBQ was as reliable as the M-ODI in an Army population. There were trends in the psychometrics suggesting the MBQ may be more sensitive to change than the M-ODI in this population.

A comparison of deployed occupational tasks performed by different types of military battalions and resulting low back pain.

With deployment Soldiers must now wear body armor and additional equipment while performing occupational tasks, representing a large demand that has not been considered when studying military occupations. The purpose of this study was to: (1) describe tasks required by different occupational battalions within a Brigade Combat Team; (2) establish the incidence of low back pain (LBP) in each battalion and; (3) determine which tasks predict LBP within the different battalions. This was a prospective cohort study investigating 805 Soldiers in a Brigade Combat Team deployed to Afghanistan for 1 year. Demographic, occupational, and fitness variables were recorded. There was no difference in time spent on fitness training between the battalions. Occupational tasks performed by deployed Soldiers vary in the level of physical demand between battalions. Infantry had the highest fitness score (257); wore the heaviest equipment (70 lb.); spent the most time wearing body armor (49 hours/week), performing dismounted patrol (29 hours/week), and lifting objects (35 hours/week); spent the least amount of time working at a desk (14 hours/week); but had a similar incidence of LBP (77%) compared to other battalions. History of LBP and time spent wearing body armor were the two most consistent predictors of LBP across battalion types.

Development of a measure to inform return-to-duty decision making after mild traumatic brain injury.

Mild traumatic brain injury (mTBI), a principal injury of the wars in Iraq and Afghanistan, can result in significant morbidity. To make accurate return-to-duty decisions for soldiers with mTBI, military medical personnel require sensitive, objective, and duty-relevant data to characterize subtle cognitive and sensorimotor injury sequelae. A military-civilian research team reviewed existing literature and obtained input from stakeholders, end users, and experts to specify the concept and develop a preliminary assessment protocol to address this need. Results of the literature review suggested the potential utility of a test based on dual-task and multitask assessment methods. Thirty-three individuals representing a variety of military and civilian stakeholders/experts participated in interviews. Interview data suggested that reliability/validity, clinical feasibility, usability across treatment facilities, military face validity, and capacity to challenge mission-critical mTBI vulnerabilities were important to ultimate adoption. The research team developed the Assessment of Military Multitasking Performance, a tool composed of eight dual and multitasking test-tasks. A concept test session with 10 subjects indicated preliminary face validity and informed modifications to scoring and design. Further validation is needed. The Assessment of Military Multitasking Performance may fill a gap identified by stakeholders for complex cognitive/motor testing to assist return-to-duty decisions for service members with mTBI.

A history of low back pain affects pelvis and trunk mechanics during a sustained lift/lower task.

This study compared three-dimensional trunk and pelvis range of motion (ROM) during a sustained asymmetric box lift/lower task between a group with a history of low back pain (HBP, n = 9) and a group with no history of low back pain (NBP, n = 9). Participants lifted an 11-kg box for 10 min at 12 cycles/min from ankle height in front to shelves 45 deg off-centre at waist height. Kinematic data were collected at the beginning (min1), middle (min5) and end of the bout (min9). Two-way analyses of variance were performed for all variables. Pelvis and trunk transverse ROM were similar at min1. By min9, HBP group did not change (31.9 ± 9 deg); however, ROM decreased in NBP group (21.6 ± 6 deg, p < 0.05). Therefore, despite no current pain, the HBP group demonstrated protective lifting mechanics compared to controls. Also discussed are implications for studying lifting paradigms at sub-maximal effort over longer periods of time. PRACTITIONER SUMMARY: Differences between groups over time demonstrate residual consequences of low back pain (LBP) in a manual materials handling scenario. Individuals with a history of LBP (pain free for 6 months) demonstrated more conservative lifting mechanics towards the end of the bout compared to controls with no history of LBP.

Loads worn by soldiers predict episodes of low back pain during deployment to Afghanistan.

STUDY DESIGN: Prospective cohort study. OBJECTIVE: To describe low back pain (LBP) sustained by soldiers deployed to Afghanistan and identify demographic, fitness, and occupational risk factors of LBP. SUMMARY OF BACKGROUND DATA: LBP is the most common injury in deployed soldiers. It results in lost duty days, medical evacuations, and permanent disability. Risk factors for LBP have not been investigated in this population. METHODS: This study investigated a US Army Brigade Combat Team deployed to Afghanistan for 1 year. Demographic, fitness, and occupational variables were recorded before and after deployment. Episodes of LBP were assessed using self-report data. Logistic regression was used to investigate predictors of (1) moderate or worse LBP developed during deployment and (2) all LBP developed during deployment. RESULTS: The incidence of moderate or worse LBP was 22% in the 805 soldiers studied. Soldiers with elevated risk of LBP were male, in Cavalry or Infantry units, wore body armor for more than 6 hr/d, worked at a desk for 1 to 4 hours a day, spent 5 to 8 hr/d lifting, spent more than 1 hr/wk on walking patrol, spent 21 to 40 hr/wk in a tactical vehicle, or wore equipment. The most parsimonious set of significant predictors for moderate or worse LBP included age, OR = 1.04 (1.01-1.08); fitness score, OR = 0.99 (0.989-0.999); the amount of time spent wearing body armor, OR = 1.16 (1.10-1.23); the amount of time spent on walking patrol, OR = 1.01 (1.003-1.02); and weight of the equipment worn, OR = 1.01 (1.002-1.013). The incidence of all LBP (minor or worse) was 77%. The most parsimonious set of significant predictors for all LBP included age, OR = 1.06 (1.02-1.09); fitness score, OR = 0.99 (0.985-0.997); history of LBP, OR = 2.94, (1.87-4.62); equipment weight, OR = 1.008 (1.003-1.01); and time spent wearing body armor, OR = 1.13 (1.07-1.19). CONCLUSION: This study found that being older, having lower fitness scores, wearing armor longer, and wearing heavier loads increased the risk of LBP in deployed soldiers. Units more likely to wear loads such as the Infantry and Cavalry and tasks commonly involving wearing loads such as patrolling all increased the risk of LBP as well.