Leading Musculoskeletal Injury Care
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Scholarly Activities

Research Activities

Are We Able to Determine Differences in Outcomes between Male and Female Service Members Undergoing Hip Arthroscopy: A Systematic Review — Orthopaedic Journal of Sports Medicine

Rhon D, Greenlee T, Dickens J, Wright A

Military females sustain higher rates of lower extremity injuries compared to males. This can include intra articular pathology in the hip. Females are considered to have worse outcomes following hip arthroscopy for femoroacetabular impingement and for hip labral repair. To confirm these statements, we queried the current literature.

Rhon, D., Greenlee, T., Dickens, J., & Wright, A. (2021). Are We Able to Determine Differences in Outcomes Between Male and Female Servicemembers Undergoing Hip Arthroscopy? A Systematic Review. Orthopaedic Journal of Sports Medicine. https://doi.org/10.1177/23259671211053034

Teaching it Forward: Peer-to-Peer Provider Training for Micro-Fragmented Adipose Tissue (MFAT) Injections for Meniscal Tears Across Multiple Military Treatment Facilities — AMSUS 2022

Smith M, West S, Malanga G, Hager N, Hulsopple C, Yuan X

Abstract submitted to Association of Military Surgeons of the United States 2022

The Musculoskeletal Injury Rehabilitation Research for Operational Readiness (MIRROR) organization, based out of the Department of Physical Medicine and Rehabilitation (PM&R) at the Uniformed Services University (USU), is dedicated to advancing musculoskeletal injury rehabilitative care within the Military Healthcare System (MHS) to reduce the burden of musculoskeletal injuries on operational readiness. Through its core infrastructure and inter-service collaborations, MIRROR facilitates training programs for medical education to expand and optimize treatments. Knee injuries are one of the most common musculoskeletal complaints among Active Duty military personnel. Autologous micro-fragmented adipose tissue (MFAT) has shown promise as a regenerative therapy for meniscal tears in the civilian population. MIRROR supports a randomized controlled trial (RCT) at multiple military treatment facilities (MTFs), with the objective to investigate the safety and efficacy of intrameniscal injection with autologous MFAT for symptomatic meniscal injuries in a military population. With the assistance of a peer-to-peer, two-day training program incorporating didactic cadaveric training and hands-on patient cases, clinicians at three MTFs garnered the procedural skills required to safely administer this novel intervention prior to the launch of this multi-site study.

Virtual Ultrasound-Guided Carpal Tunnel Release Training for Military Providers: Advancing Medical Education Amidst a Global Pandemic — AMSUS 2022

Smith M, West S, Persinger J, Hager N, Smith J, Miller M, Yuan X, Reece D

Abstract submitted to Association of Military Surgeons of the United States 2022

The COVID-19 pandemic has taken a significant toll on global medical education and research since March 2020, prompting a surge of virtual learning. Like other research entities, the Musculoskeletal Injury Rehabilitation Research for Operational Readiness (MIRROR) organization, based out of the Department of Physical Medicine and Rehabilitation (PM&R) at the Uniformed Services University (USU), was not spared from the pandemic’s impact on research operations and adapted to persevere, despite setbacks. At the heart of the organization’s mission, MIRROR provides clinicians and researchers with the support and infrastructure to advance musculoskeletal injury rehabilitative care by facilitating training programs for medical education. According to the Defense Medical Epidemiology Database, nearly 17,000 Active Duty service members were diagnosed with carpal tunnel syndrome (CTS) in 2016, the most common peripheral entrapment neuropathy. MIRROR currently supports a study at multiple military treatment facilities (MTFs) comparing Ultrasound-Guided Carpal Tunnel Release (USCTR) to the current standard-of-care surgical release with respect to return to duty and clinical outcomes in the military population with CTS. With the aid of an innovative virtual platform, training for this enhanced intervention continued during the pandemic, propelling MIRROR’s mission to advance military medicine.

Transforming Clinical Clerkships Using Innovative Distributed Technologies — AMSUS 2022

Persinger J, Benbassat D

Abstract submitted to Association of Military Surgeons of the United States 2022

The Department of Physical Medicine and Rehabilitation (PM&R) at the Uniformed Services University (USU) started offering a musculoskeletal (MSK) ultrasound (US) clerkship to USU medical students in 2019. It included resident didactic instruction on the fundamental principles of ultrasonography and hands-on clinical instruction using the ultrasound machine and transducers. Despite the clerkship’s tangible benefits to undergraduate medical students, it was discontinued following the 2020 pandemic’s stay-at-home orders. To ensure continued delivery of the course, the department transformed its traditional clerkship training using innovative distributed technologies.

Delayed Timing of Rehabilitation is Associated with Recurrence and Higher Healthcare Utilization After Ankle Sprain Injury in the Military Health System — AASPT 2021 and EFAS 2021

Rhon D, Fraser J, Greenlee T, Jain T, Cook C

This abstract won the American Academy of Sports Physical Therapy 2021 Annual Meeting & Scientific Conference Research Report Award.

Ankle sprains are common, disabling, and costly. Timely rehabilitation may improve outcomes compared to delayed care. Our goal was to investigate the influence of time taken to begin physical rehabilitation on injury recurrence and one-year ankle-related medical care costs.

Fractures and Chronic Recurrence Are Commonly Associated with Ankle Sprains: A 5-Year Population Level Cohort of Patients Seen in the Military Health System — EFAS 2021

Rhon D, Fraser J, Westrick R, Umlauf J, Cook C

Abstract submitted to European Foot and Ankle Society Conference

While ankle-foot injuries are ubiquitous and affect ~16% of all military service-members, granularity of the evidence in this population is lacking. Therefore, the purpose of this retrospective cohort study was to characterize ankle sprains in the US military between 2009 and 2013.

Does Surgery for Cruciate Ligament and Meniscus Injury Increase the Risk of Comorbidities at 2 Years in the Military System?

cook c, sheean a, zhou l, kyong m, rhon d

This study aims to determine whether surgery for cruciate ligament (anterior or posterior) or meniscus injury increased risks of subsequent comorbidities in beneficiaries of the Military Health System. The study was a retrospective case-control design in which individuals with cruciate or meniscus injuries were divided into two groups (surgery or none). Data were pulled 12 months prior and 24 months following each respective event and presence of comorbidities were compared between the two groups. Bivariate analyses and logistic regression were used to determine if surgery increased the odds of comorbidities. Participants included 1,686 with a cruciate ligament injury (30.1% treated surgically) and 13,146 with a meniscus injury (44.4% treated surgically). Bivariate comparisons of surgery versus nonsurgical treatment found multiple significant differences. After adjusting for covariates, a significant (p < 0.05) protective effect was seen only for meniscus surgery for concussion, insomnia, other mental health disorders, depression, and substance abuse. Surgery had no increased/decreased risk of comorbidities for cruciate ligament injuries. For meniscus injuries, surgery demonstrated a protective effect for six of the comorbidities we assessed. The treatment approach (surgery vs. nonsurgical) did not change the risk of comorbidities in those with a cruciate ligament injury. It is noteworthy that three of the six comorbidities involved mental health disorders. Although the study design does not allow for determination of causation, these findings should compel future prospective study designs that could confirm these findings.

Cook CE, Sheean AJ, Zhou L, Min KS, Rhon DI. Does Surgery for Cruciate Ligament and Meniscus Injury Increase the Risk of Comorbidities at 2 Years in the Military System? J Knee Surg. 2023 Apr;36(5):465-474. doi: 10.1055/s-0041-1736197. Epub 2021 Oct 5. PMID: 34610640.

Timing of Rehabilitation is Associated with Recurrence After Ankle Sprain Injury in the Military Health System - MHSRS 2021

Rhon D, Greenlee t, Fraser J

Abstract accepted as a poster for 2021 MHSRS

The purpose of this paper was to investigate the influence of time taken to begin physical rehabilitation after ankle sprain on injury recurrence and medical costs. Because comorbidities can influence costs, we also investigated the effect modification of select comorbidities on the relationship between the timing of rehabilitation and these outcomes (injury recurrence and injury-related costs).

Less than half of individuals that sought care for an ankle sprain received any physical rehabilitation procedures as part of their care. For patients that underwent physical rehabilitation, longer times to the first rehabilitation visit were associated with a higher risk for injury recurrence. The exception was with the isolated lateral ankle sprain group. However, the large majority of ankle sprains in the “unspecified sprain” subgroup were likely lateral ankle sprains. This was the case regardless of whether the ankle sprain was first managed in military versus civilian clinics. Longer times to rehab were also associated with greater total ankle-related medical costs for the year following the initial injury. Individuals that sought care for pain-related comorbid medical conditions in the prior year were more likely to experience a recurrent ankle sprain injury (those with anxiety and PTSD) and more likely to have increased ankle-related medical costs ( those with insomnia, sleep apnea, anxiety, PTSD, and substance abuse disorders), highlighting the potentially complex and multivariate relationships that influence recovery after injury.

This is the first study to assess the influence of timing of rehab on outcomes after ankle sprains injuries. For individuals who undergo rehab for an ankle sprain, the earlier they start rehab, the lower their likelihood of recurrence and the lower the number of downstream ankle-related visits and costs they will incur.

Antimicrobial Blue Light, Oregano Oil, and CZ Gel Manage Staphylococcus aureus Biofilms at the Skin-Implant Interface of Percutaneous Osseointegrated Prosthetics in an Ex Vivo Setup — MHSRS 2021

Ong J, Godfrey R, Peterson T, Tam J, Drake L, Navarian A, Epperson R, Isaacson B , Williams D

Abstract submitted to Military Health System Research Symposium 2021

Percutaneous osseointegrated prosthetics (POPs) are becoming available for those with limb loss as an alternative to prosthetic socket technology. POPs make it easier for amputees to attach and detach prostheses, and improve mechanical force feedback. Nevertheless, the percutaneous nature of POPs makes them susceptible to biofilm-related infection, with rates ranging as high as 30%; limiting a more widespread adoption. Infection causes skin irritation, discomfort, and may lead to deep infection if left uncontrolled. We hypothesized that antimicrobial blue light (aBL) can manage biofilm burden. However, while aBL disrupts bacterial membranes and kills cells, it may not completely eradicate biofilms as a standalone therapy. As a result, we explored the efficacy and potential synergy of oregano oil and CZ (anti-biofilm compound). Multi-day applications were tested against Staphylococcus aureus biofilms; common to POPs. These therapies may lead to more effective treatments for managing the S. aureus biofilm burden at the skin-implant interface of POPs. We built an ex vivo system using sterilized sheep skin (male/female) to simulate a POP environment translatable to an ovine model. S. aureus biofilms were grown on titanium (Ti) coupons in CDC biofilm reactors which were then used to inoculate the ex vivo skin-implant interface sites. For aBL treatment, inoculated skin samples were exposed twice daily to 405 nm aBL for 1 hour (900 J/cm2), with 6 hours between exposures; samples were covered and incubated when not treated. Oregano (10% w/v) and CZ (2% w/v) were formulated into gels. Each day, 1.5 mL of gel was aseptically applied to each sample. Samples were wrapped and incubated for 24 hours. All methods were tested at 1, 2, 3, 4, and 5-day intervals (n=8 per day). Bacteria were quantified using 10-fold dilution. Colony forming unit (CFU) counts were averaged and compared against a control set (skin inoculated with S. aureus, but not treated).

Military Orthopaedics Tracking Injuries and Outcomes Network (MOTION) — MHSRS 2021

Bradley M, Tenan M, Dickens J

Abstract submitted to Military Health System Research Symposium 2021

Musculoskeletal injuries (MSKI) remain the largest source of disability, readiness impairment, non-deployable status, and separation within the US Military.  Although MSKI are of such magnitude, severity, and cost, efforts to uniformly collect and evaluate outcomes following injury and treatment are lacking due to decentralized datasets and the migratory nature of military service members. The Military Orthopaedics Tracking Injuries and Outcomes Network (MOTION) seeks to address this issue by establishing a DoD-wide enterprise system for the reliable collection of validated health outcome measures related to musculoskeletal conditions that cause the greatest impact on readiness, disability, and well-being. MOTION is an ongoing collection of clinician data along with assessments from patients who are receiving treatment of MSKI. The target population are DEERS-eligible adults, including both active duty and non-active duty retirees and beneficiaries, who will receive treatment of an upper extremity, lower extremity, or spine MSKI. Civilian dependents may serve as a “control group.” All participants are prospectively enrolled at the time of their initial presentation to the orthopaedic or allied health clinic.  Patient reported outcomes are collected electronically at the following time points: pre-operative visit, 6-weeks post-op, 6-months, 12 months, 2 years, 5 years, 10 years, 15 years, and 20 years.

One Weak Link Affects the Chain: Incidence of Lumbar, Hip, and Ankle Injuries in Patients with Patellofemoral Pain in the MHS — MHSRS 2021

Young J, Greenlee T, Rhon D

Abstract submitted to Military Health System Research Symposium 2021

Over half of all musculoskeletal injuries incurred by service members take place in the lower extremity and lumbar spine. In the first 6 months of 2019, musculoskeletal injuries alone were attributed to 59% of limited duty days. Knee disorders are some of the most common injuries of the lower extremity, contributing to high rates of osteoarthritis in service members and veterans. What is not seen as clearly is the potential influence that knee disorders have on the genesis of adjacent joint injuries. When pain and dysfunction affect the knee, do the compensatory adjustments required to manage these symptoms increase injuries in an adjacent joint (ankle, hip, spine)? Some evidence suggests that the presence of one lower extremity disorder may be a risk factor for the development of a more proximal or distal musculoskeletal disorder. Hip strength deficits have been shown to contribute to knee and foot/ankle disorders, foot disorders can impact the knee and lumbar spine, and foot and ankle symptoms have led to knee pain in patients with knee osteoarthritis. However, it is unclear what proportion of patients with a knee disorder end up sustaining an adjacent-joint injury, or what proportion of patients with a knee disorder had an adjacent joint injury prior to their knee disorder. This information can help clinicians and research teams better understand what patients may be at risk for additional injury sequelae and can help determine the content for optimal injury prevention or risk reduction strategies for these patients. Therefore, the purpose of this study was to investigate the incidence of lumbar, hip, and ankle injuries after a diagnosis of patellofemoral pain in the Military Health System. Because some evidence has shown a relationship between the spine, hip and ankle and subsequent knee disorders, a secondary aim was to identify the incidence of lumbar, hip, and ankle injuries prior to a patellofemoral pain diagnosis.

Are We Able to Determine Differences in Outcomes Between Male and Female Service Members Undergoing Hip Arthroscopy: A Systematic Scoping Review — MHSRS 2021

Greenlee T, Wright A, Dickens J, Rhon D

Abstract submitted to Military Health System Research Symposium 2021.

Research has shown that females in the military are at increased risk (as much as 3x greater) to sustain lower extremity musculoskeletal injuries than their male counterparts. For instance, females in Army basic training have 2.2 times the incidence of lower extremity overuse injuries as males. The hip is a commonly injured joint in the lower extremity, most often by stress fractures, and particularly problematic amongst female military members. Surgical treatment of non-acute hip pain in young athletes is becoming a mainstream intervention, with an 18-fold increase from 1999 to 2009 in the United States. In the Military Health System (MHS), hip arthroscopy is rising at similar rates. Females in other settings are considered to have worse outcomes following surgical interventions for some of these injuries, such as hip arthroscopy for femoroacetabular impingement or labral repair; however, the data on the influence of female sex on outcomes after hip arthroscopy are conflicting. Females, in general, are poorly represented in exercise and sports medicine research. It is unknown whether the current body of research has been designed to reveal differences related to sex and hip arthroscopy in the military. The recent shift within the last decade to open up combat military occupations to individuals of both sexes elevates the importance of understanding sex-specific outcomes in this setting. Females make up approximately 15% of all military service members, and 10% of service members that deploy. This has led to symposiums, task forces, and calls for a greater research focus on the issue of injuries in female military service members. These calls align strongly with a push to improve research on sex disparity in general, and specifically in female athletes which is greatly lacking.

Characterizing Low Back Pain Healthcare Utilization in the Military Health Care System by Active-Duty Service Members with an Extremity Amputation — MHSRS 2021

Rhon D, Greenlee T, Farrhoki S, Young

Abstract submitted to Military Health System Research Symposium 2021.

Extremity amputation is a life-altering consequence associated with some traumatic injuries. Due to occupational hazards inherent with military service, service members are at higher risk for extremity amputation compared to their civilian counterparts. Between January 2001 and October 2017, 1705 service members with combat deployment history sustained an extremity amputation (2316 unique extremity amputations). The majority of amputations were in the lower extremity (1914 total amputations) compared to the upper extremity (402 total amputations). Unfortunately, physical disability is not limited to the loss of limb alone but also accompanied by many other medical morbidities. One of the most commonly reported is low back pain. Alteration in biomechanical, psychological, and social factors after limb amputation can contribute to the development of back pain-related symptoms and disability. Back pain with extremity amputation has been investigated in prior studies, but a more granular assessment of low-back pain-related healthcare utilization in extremity amputation and back pain has not been conducted. Characterizing the healthcare utilization provides an improved understanding of the medical burden incurred to the Military Health System by these patients specific to low back pain. The purpose of this study was to characterize back pain-related healthcare utilization in beneficiaries of the Military Health System that have undergone an amputation. A secondary aim was to assess the differences in healthcare utilization and costs between regions of amputation (upper versus lower limb).

Randomized Control Trial of combined Cryotherapy with Compression Versus Cryotherapy Alone After Arthroscopic Orthopaedic Surgery — MHSRS 2021

Anderson A, Bradley M, Dalgarno R, Lucio W, Purvis H, Kilcoyne K, Tucker C, Dickens J

Abstract submitted to Military Health System Research Symposium 2021

Cold therapy (cryotherapy) has been widely used for adjuvant treatment of postoperative pain management in orthopaedic surgery. Postoperative cryotherapy with compression is proposed as a method of reducing pain and the inflammatory response in the early postoperative period after orthopaedic arthroscopic procedures. Many devices are available, but few can guarantee temperature regulation during prolonged periods of use and therefore have been criticized. The arrival of new advanced cryotherapy devices has made it possible to test the effect of prolonged cooling on rehabilitation after arthroscopic orthopaedic procedures. Therefore, the purpose of this study was to determine the impact of cryotherapy with compression (using Game Ready®) versus cryotherapy without compression (standard of care ice packs) on 1) postoperative pain control, 2) patient reported outcomes, and 3) number and dose in morphine milligram equivalents (MME) of pain medications taken after arthroscopic surgery.

The Effectiveness of Telehealth Gait Retraining in Addition to Standard Physical Therapy Treatment for Overuse Knee Injuries in Soldiers: A Randomized Clinical Trial — MHSRS 2021

Crowell M, Brindle R, Mason J, Pitt W, Miller E, Ford K, Peel S, Goss D

Abstract submitted to Military Health System Research Symposium 2021

Each year, approximately half of all military personnel sustain a musculoskeletal injury. The majority of injuries can be classified as overuse injuries, with half of those due to exercise. Running is the most frequently reported injury producing activity and the knee is one of most injured joints. During running, a non-rearfoot strike pattern reduces loading rates and knee joint work. Thus, a gait retraining intervention to alter foot strike pattern for patients with a rearfoot strike pattern during running may improve rehabilitation outcomes for patients with overuse knee injuries. The purpose of this randomized clinical trial was to determine the effects of a telehealth gait retraining intervention on self-reported pain and function in patients with an overuse knee injury. We hypothesized that patients who underwent the telehealth intervention along with standard treatment would report greater improvements in pain intensity, condition, function, and running ability compared to patients who received only standard physical therapy treatment.

Normative Values for the Patient Reported Outcome Measures in the Shoulder within an Active Military Population — MHSRS 2021

Corey S, Davi S, Posner M, Donohue M, Slabaugh M, Robins R, LeClere L, Bradley M, Hood M, Dickens J, Cameron K

Abstract submitted to Military Health System Research Symposium 2021

Shoulder injuries are common within military populations and shoulder dislocation and subluxation injuries are a leading cause for surgical intervention impacting military readiness. Patient-reported outcome measures (PROMs) are important in clinical practice and may inform management and return to duty decisions; however, normative values for PROMs for the shoulder in young military populations are limited. The purpose of this study was to describe normative values for the Patient Reported Outcome Measurement Information System (PROMIS) Physical Function Scale, Single Assessment Numeric Evaluation (SANE), and Brief Resilience Scale (BRS) in active young military service members with and without a history of shoulder instability and to compare scores by sex at the time of accession.

Running Mechanics 6 Weeks Post Conservative Management Using Loadsols for an Active-Duty Female with Lower Leg Chronic Exertional Compartment Syndrome: A Case Study — MHSRS 2021

Velasco T, Peel S, Hulsopple C, Gornoski L, Goss D, Leggit J

Abstract submitted to Military Health System Research Symposium 2021

Chronic exertional compartment syndrome (CECS) predominantly affects highly active individuals’ lower legs, especially among military service members. The current treatment for CECS is a surgical fasciotomy of the involved lower leg compartment.  The post-surgical patient outcomes are mixed. Emerging non-surgical treatments with botulinum toxin A (BoNT-A) and gait retraining (GR) are alluring alternatives. BoNT-A may reduce compartment pressures and pain in individuals with CECS. The predominate muscle of the lower leg anterior compartment is the tibialis anterior. Using a forefoot strike pattern while running, the tibialis anterior decreases eccentric activity and anterior compartment pressure. Using gait retraining (GR) to alter foot strike patterns from rearfoot to forefoot running decreases ground reaction forces (GRF) and reduces leg pain. Published case series on these non-surgical interventions have promising results. When GR is offered as an intervention it is through supervised clinic visits or partial home-based training during a 6-week period.  These case series obtain kinetic data through instrumented treadmills, mainly in a male population. An alternative to using an instrumented treadmill are Loadsol sensors connected to a Bluetooth device and placed inside each shoe to assess kinetic data while running. The purpose of this case study was to observe foot strike patterns and review kinetic changes identified with Loadsol sensors in a female with bilateral lower extremity CECS after BoTN-A and home-based GR.

The Impact of Entry Variables on the Transition Pathway for Soldiers Enrolled in Army Recovery Care Program — MHSRS 2021

Dintaman J, Ebert M, Sorensen I, Hisle-Gorman E

Abstract submitted to Military Health System Research Symposium 2021.

The Army Recovery Care Program (ARCP), originally the Warrior Transition Program, was created in 2007 to assist in the care, recovery, and transition of Army soldiers who required case management due to complex medical conditions or injuries. Initially, the ARCP consisted primarily of wounded or injured individuals evacuated from the wars in the Middle East but gradually grew to include soldiers with non-combat related conditions requiring prolonged and multidisciplinary care. Stabilized and recovered members of the ARCP eventually transition back to the force or are medically retired if their clinical condition prohibits further military service. A limited number of participants succumb to their injury or illness or are administratively separated from the program due to non-compliance. The early ability to identify the most appropriate transition pathway for program participants is important to ensuring program resources are directed efficiently and effectively. Whether there is a relationship between the conditions prompting entry into the ARCP and the subsequent transition pathway for soldiers is unknown.

The Impact of Reason for Entry and Presenting Medical Conditions on the Length of Time in Army Warrior Care and Transition Program — MHSRS 2021

Ebert M, Sorensen I, Dintaman J, Hisle-Gorman E

Abstract submitted to Military Health System Research Symposium 2021.

The Army Warrior Care and Transition Program (WCTP), now the Army Recovery Care Program (ARCP), was launched in 2007 as a comprehensive rehabilitation program with the primary aim of assisting wounded, ill and injured soldiers to return to the fighting force, or successfully transition from the military. Since its inception, tens of thousands of Soldiers have entered the program for treatment for a broad range of physical and mental/behavioral health conditions. However, the impact of the nature of a soldier’s entry into the program, as well as the type or types of injuries sustained on the amount of time spent in the ARCP is not known. The objective is to explore the impact of how service members entered the program, the number of conditions they presented with, and what conditions they had on how much time was spent in the ARCP.

The Impact of Family, Demographic and Programmatic Differences on Length of Time in Army Warrior Care and Transition Programs — MHSRS 2021

Hisle-Gorman E, Dintaman J, Ebert M, Sorensen I

Abstract submitted to Military Health System Research Symposium 2021

An inevitable outcome of armed conflict is combat injury of service men and women. Since the initiation of conflict in Afghanistan in Oct 2001 wounded soldiers have been receiving targeted care, at Medical Centers but the formation of a formal comprehensive program was not initially available. The Army Warrior Care and Transition Program (WCTP) was launched in 2007 as a comprehensive rehabilitation program with the primary aim of assisting wounded, ill and injured soldiers to return to the fighting force, or successfully transition out of the military.  Length of time participates are in the program is an important indicators of program efficacy and cost.  The impact of programmatic, demographic and family levels factors on length of time soldiers stay in the WCTP is not known. The objective is to explore the impact of programmatic, demographic and family level factors on length of time soldiers are in the WCTP.