Return to Duty Rate of Amputee Soldiers in the Current Conflicts in Afghanistan and Iraq

Healthcare Utilization Following Hemipelvectomy or Hip Disarticulation in the Military Health System

INTRODUCTION

Amputations at the hip and pelvic level are often performed secondary to high-energy trauma or pelvic neoplasms and are frequently associated with a prolonged postoperative rehabilitation course that involves a multitude of health care providers. The purpose of this study was to examine the health care utilization of patients with hip- and pelvic-level amputations that received care in the U.S. Military Health System.

MATERIALS AND METHODS

We performed a retrospective review of all patients who underwent a hip- or pelvic-level amputation in the Military Health System between 2001 and 2017. We compiled and reviewed all inpatient and outpatient encounters during three time points: (1) 3 months pre-amputation to 1 day pre-amputation, (2) the day of amputation through 12 months post-amputation, and (3) 13-24 months post-amputation. Health care utilization was defined as the average number of encounter days/admissions for each patient. Concomitant diagnoses following amputation including post-traumatic stress disorder, traumatic brain injury, anxiety, depression, and chronic pain were also recorded.

RESULTS

A total of 106 individuals with hip- and pelvic-level amputations were analyzed (69 unilateral hip disarticulation, 6 bilateral hip disarticulations, 27 unilateral hemipelvectomy, 2 bilateral hemipelvectomies, and 2 patients with a hemipelvectomy and contralateral hip disarticulation). Combat trauma contributed to 61.3% (n = 65) of all amputations. During the time period of 3 months pre-amputation, patients had an average of 3.8 encounter days. Following amputation, health care utilization increased in both the year following amputation and the time period of 13-24 months post-amputation, averaging 170.8 and 77.4 encounter days, respectively. Patients with trauma-related amputations averaged more total encounter days compared to patients with disease-related amputations in the time period of 12 months following amputation (203.8 vs.106.7, P < .001) and the time period of 13-24 months post-amputation (92.0 vs. 49.0, P = .005). PTSD (P = .02) and traumatic brain injuries (P < .001) were more common following combat-related amputations.

CONCLUSIONS

This study highlights the increased health care resource demand following hip- and pelvic-level amputations in a military population, particularly for those patients who sustained combat-related trauma. Additionally, patients with combat-related amputations had significantly higher rates of concomitant PTSD and traumatic brain injury. Understanding the extensive needs of this unique patient population helps inform providers and policymakers on the requirements for providing high-quality care to combat casualties.

The Exploration of the GWOT Combat Amputee's Experience With Longitudinal Care: A Qualitative Study

INTRODUCTION

Contemporary advances in combat medicine have allowed greater numbers of wounded service members to survive their injuries. An estimated 1,705 combat veterans sustained major lower or upper extremity amputations between 2001 and 2017 during the Global War on Terror. This study intends to answer the following question utilizing a qualitative study design: What were the common and abnormal experiences of the Global War on Terror combat amputees relative to their mechanism of injury, perception of injury, and systems of care utilized during their recovery and rehabilitation process?.

METHODS

During the months of December 2022 and January 2023, individual semi-structured interviews were conducted with U.S. Marines that served in the Global War on Terror (total n = 10). Deductive and inductive approaches were employed to identify codes, themes, and meta-themes in the data.

RESULTS

All participants deployed to Afghanistan between the years 2010 and 2014 and were assigned to the following military occupational specialties: Explosive Ordnance Disposal technicians (total n = 2); combat engineers (total n = 2); and infantrymen (total n = 6). Analysis of data collected from interviews highlighted these key observations: (1) Themes in the combat amputee experience include support, systems of care, and mindset and (2) the themes synergistically contribute to the meta-themes mental health and pain and vice versa. As all participants were subjected to a blast mechanism of injury, it is difficult to determine if this played a role in deviating rehabilitation and recovery processes. Perception of injury and how well participants adapted to their new lifestyle, meaning how optimistic they were, appeared to play a significant role in recovery. Participants had mixed feelings about the care they had received but generally spoke favorably of military hospitals and were frustrated with the Veteran Affairs, and there was no clear consensus on their relationship with civilian health care, though most participants chose to seek most of their care through the Veteran Affairs.

CONCLUSION

Based on the research question, this study found an intricate relationship between mental health, pain, and the experiences of the participants regarding their care and rehabilitation. However, the nature of qualitative research makes it impossible to determine generalizations that can be used to create meaningful change to address improving combat amputee veteran care. Further research into long-term health outcomes based on hypotheses not evaluated in existing literature would further improve the ability of health care providers to care for this unique patient population.

Within-subject effects of standardized prosthetic socket modifications on physical function and patient-reported outcomes

Background

Among the challenges of living with lower limb loss is the increased risk of long-term health problems that can be either attributed directly to the amputation surgery and/or prosthetic rehabilitation or indirectly to a disability-induced sedentary lifestyle. These problems are exacerbated by poorly fit prosthetic sockets. There is a knowledge gap regarding how the socket design affects in-socket mechanics and how in-socket mechanics affect patient-reported comfort and function. The objectives of this study are (1) to gain a better understanding of how in-socket mechanics of the residual limb in transfemoral amputees are related to patient-reported comfort and function, (2) to identify clinical tests that can streamline the socket design process, and (3) to evaluate the efficacy and cost of a novel, quantitatively informed socket optimization process.

Methods

Users of transfemoral prostheses will be asked to walk on a treadmill wearing their current socket plus 8 different check sockets with designed changes in different structural measurements that are likely to induce changes in residual limb motion, skin strain, and pressure distribution within the socket. Dynamic biplane radiography and pressure sensors will be used to measure in-socket residual limb mechanics. Patient-reported outcomes will also be collected after wearing each socket. The effects of in-socket mechanics on both physical function and patient-reported outcomes (aim 1) will be assessed using a generalized linear model. Partial correlation analysis will be used to examine the association between research-grade measurements and readily available clinical measurements (aim 2). In order to compare the new quantitative design method to the standard of care, patient-reported outcomes and cost will be compared between the two methods, utilizing the Wilcoxon-Mann-Whitney non-parametric test (aim 3).

Discussion

Knowledge on how prosthetic socket modifications affect residual bone and skin biomechanics itself can be applied to devise future socket designs, and the methodology can be used to investigate and improve such designs, past and present. Apart from saving time and costs, this may result in better prosthetic socket fit for a large patient population, thus increasing their mobility, participation, and overall health-related quality of life.

Trial registration

ClinicalTrials.gov NCT05041998. Date of registration: Sept 13, 2021.

Should I Stay or Should I Go? Identifying Intrinsic and Extrinsic Factors in the Decision to Return to Duty Following Lower Extremity Injury

INTRODUCTION

Rehabilitation research of wounded service members (SMs) commonly focuses on physical ability to return to duty (RTD) as a measure of successful recovery. However, numerous factors or barriers may influence a SM's ability and/or desire to RTD after lower extremity musculoskeletal trauma. SMs themselves as well as the clinical care team that works with them daily, often for years at a time, both offer unique perspectives on the influential factors that weigh into decisions to RTD. The purpose of this study was to identify the intrinsic and extrinsic factors patients and clinicians recognized as influencing the decision to RTD after severe lower extremity trauma.

MATERIALS AND METHODS

Thirty-two SMs with severe lower extremity trauma (amputation and lower limb salvage) and 30 providers with at least 2 years' experience caring for SMs with similar injuries participated separately in either a SM or provider/clinician focus group. Open-ended questions on factors influencing RTD and other rehabilitation success were discussed. Data analysis consisted of qualitative transcription and participatory active sorting, followed by thematic coding and grouping of qualitative data.

RESULTS

Individual (health condition, personal traits, and career consideration), interpersonal (clinician's impact, family influence, and peer influence), health care system (systems of care, transdisciplinary rehabilitation, and innovation availability), and institutional (policy, benefits, and unit/commander) themes emerged amongst SM patients and clinicians. Expected frequently occurring themes common to both groups were the influence of the team and family unit, as well as career trajectory options after a severe injury. An unexpected theme was acknowledgment of and dissatisfaction with the recent dismantling of institutional systems that support wounded SMs. Patients placed less emphasis on severity of injury and greater emphasis on system and policy barriers than did clinicians.

CONCLUSIONS

Characterization and classification of these clinician and SM-identified factors that influence the decision to RTD after severe lower extremity trauma is expected to improve the efficacy of future rehabilitation efforts and clinical practice guidelines by providing the clinical team the knowledge necessary to recognize modifiable barriers to patient success. A better understanding of factors influencing RTD decision-making may support policies for mitigating RTD barriers, better monitoring of the changing landscape of RTD after lower extremity trauma, improving systems of health care, and/or reducing turnover and facilitating force readiness.

Occupational Therapy Practice Patterns for Military Service Members With Upper Limb Amputation

INTRODUCTION

Military Service Members (SMs) with upper limb (UL) amputation have unrestricted access to occupational therapy (OT) services. Identifying OT interventions used based on clinical rationale and patient needs can provide insight toward developing best practice guidelines. The purpose of this retrospective observational study was to identify preferred OT practice patterns for U.S. Military SMs treated in Military Treatment Facilities, who have sustained various levels of deployment-related UL amputation.

METHODS

The study sample was ascertained from the Expeditionary Medical Encounter Database housed at the Naval Health Research Center in San Diego, California. SMs with an immediate (within 24 hours of injury) deployment-related unilateral major UL amputation (partial hand and proximal), occurring between January 2001 and December 2014 were identified. SMs with concurrent major lower limb amputation (partial foot and proximal) were excluded. Frequency of OT outpatient visits and units of treatment received were quantified in 3-month increments during the first year after amputation and compared for individuals with above elbow (at or proximal to elbow joint) and below elbow (distal to the elbow joint including partial hand) amputation. This study was approved by the Naval Health Research Center Institutional Review Board.

RESULTS

A total of 29,878 encounters occurred during first year after amputation in 148 patients, who had sustained UL loss during the first year after amputation. Active treatments were included in 79.2% of all treatments, followed by manual therapy (13.7%) and modalities (13.5%). A higher number of OT encounters occurred in the above elbow amputation group-the first year of treatment with significantly higher mean number of treatments months 4 to12. A similar pattern in OT encounters was observed in the active therapy category with significantly higher mean number of treatments occurring in above elbow limb loss group in months 10 to 12.

CONCLUSION

Findings of the current study suggest SMs with UL amputation utilize OT services often within the first year after injury and those who have sustained amputation proximal to the elbow received more therapy visits than their below elbow counterparts during months 4 to 12. Prosthetic training, therapeutic activities, and therapeutic exercise can be expected to be the highest used active interventions in the first year following UL amputation. Further research is needed to determine details on types and frequency of therapy utilization and recommended therapy strategies.

The Effectiveness of the DoD/VA Mobile Device Outcomes-Based Rehabilitation Program for High Functioning Service Members and Veterans with Lower Limb Amputation

Introduction

The objective was to determine if the Mobile Device Outcomes-based Rehabilitation Program (MDORP) improved strength, mobility, and gait quality in service members (SMs) and Veterans with lower limb amputation (LLA).

Methods

Seven SMs and 10 Veterans with LLA enrolled and were trained to use a mobile sensor system, called Rehabilitative Lower Limb Orthopedic Analysis Device (ReLOAD). ReLOAD provided participants with real-time assessment of gait deviations, subsequent corrective audio feedback, and exercise prescription for normalizing gait at home and in the community. After baseline testing, prosthetic gait and exercise training, participants took ReLOAD home and completed an 8-week walking and home exercise program. Home visits were conducted every 2 weeks to review gait training and home exercises.

Results

Significant improvements in hip extensor strength, basic and high-level mobility, musculoskeletal endurance, and gait quality (P &lt; 0.05) were found at the completion of the 8-week intervention.

Conclusion

Preliminary MDORP results are promising in its ability to improve basic and high-level mobility, lower limb strength, and gait quality in a group of SMs and Veterans with LLA. In addition, “booster” prosthetic training may be justified in an effort helps maintain an active lifestyle, promotes prosthetic use, and mitigates secondary health effects.

Amputations versus Salvage: Reconciling the Differences

BACKGROUND

 There are many factors to consider when choosing between amputations versus salvage in lower extremity reconstructive surgery. Postoperative functionality and survival benefit are critical factors when deciding between limb salvage and amputation.

METHODS

 In this review, we present the evidence and the risks and benefits between these two options in the setting of the acute, trauma population and the chronic, diabetes population.

RESULTS

 The trauma population is on average young without significant comorbidities and with robust vasculature and core strength for recovery. Therefore, these patients can often recover significant function with anamputation and prosthesis. Amputation can therefore be the more desirable in this patient population, especially in the case of complete traumatic disruption, unstable patients, high risk of extensive infection, and significant nerve injury. However, traumatic lower extremity reconstruction is also a viable option, especially in the case of young patients and those with intact plantar sensation and sufficient available tissue coverage. The diabetic population with lower extremity insult has on average a higher comorbidity profile and often lower core strength. These patients therefore often benefit most from reconstruction to preserve limb length and improve survival. However, amputation may be favored for diabetics that have no blood flow to the lower extremity, recalcitrant infection, high-risk comorbidities that preclude multiple operations, and those with end stage renal disease.

CONCLUSION

 Many patient-specific factors should be considered when deciding between amputation vs. salvage in the lower extremity reconstruction population.

The Military Extremity Trauma Amputation/Limb Salvage (METALS) Study: Outcomes of Amputation Compared with Limb Salvage Following Major Upper-Extremity Trauma

BACKGROUND

Severe upper-extremity injuries account for almost one-half of all extremity trauma in recent conflicts in the Global War on Terror. Few long-term outcomes studies address severe combat-related upper-extremity injuries. This study's objective was to describe long-term functional outcomes of amputation compared with those of limb salvage in Global War on Terror veterans who sustained severe upper-extremity injuries. Limb salvage was hypothesized to result in better arm and hand function scores, overall functional status, and quality of life, with similar pain interference.

METHODS

This retrospective cohort study utilized data from the Military Extremity Trauma Amputation/Limb Salvage (METALS) study for a subset of 155 individuals who sustained major upper-extremity injuries treated with amputation or limb salvage. Participants were interviewed by telephone 40 months after injury, assessing social support, personal habits, and patient-reported outcome instruments for function, activity, depression, pain, and posttraumatic stress. Outcomes were evaluated for participants with severe upper-extremity injuries and were compared with participants with concomitant severe, lower-extremity injury. The analysis of outcomes comparing limb salvage with amputation was restricted to the 137 participants with a unilateral upper-extremity injury because of the small number of patients with bilateral upper-extremity injuries (n = 18).

RESULTS

Overall, participants with upper-extremity injuries reported moderate to high levels of physical and psychosocial disability. Short Musculoskeletal Function Assessment (SMFA) scores were high across domains; 19.4% screened positive for posttraumatic stress disorder (PTSD), and 12.3% were positive for depression. Nonetheless, 63.6% of participants were working, were on active duty, or were attending school, and 38.7% of participants were involved in vigorous recreational activities. No significant differences in outcomes were observed between patients who underwent limb salvage and those who underwent amputation.

CONCLUSIONS

Severe, combat-related upper-extremity injuries result in diminished self-reported function and psychosocial health. Our results suggest that long-term outcomes are equivalent for those treated with amputation or limb salvage. Addressing or preventing PTSD, depression, chronic pain, and associated health habits may result in less disability burden in this population.

LEVEL OF EVIDENCE

Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Cognitive Characteristics Associated With Device Adoption, Skill Retention, and Early Withdrawal From a Study of an Advanced Upper Limb Prosthesis

OBJECTIVE

The aim of the study was to examine the role of cognition in device adoption, skill retention, and withdrawal from a study of an advanced upper limb prosthesis (the DEKA Arm).

DESIGN

T tests and Wilcoxon rank-sum tests were used to compare test performance among study completers and noncompleters. Multivariable regression analyses were used to predict study withdrawal and DEKA Arm skill retention.

RESULTS

Compared with self-withdrawn participants, those who were withdrawn by study staff performed significantly worse on tests indexing processing speed, set-shifting, and memory encoding. The DEKA Arm configuration (transradial, transhumeral, shoulder-based on amputation level) was a stronger predictor of skill retention than neuropsychological test performance.

CONCLUSIONS

Frontally-mediated cognitive skills may influence the successful adoption of the DEKA Arm. The DEKA Arm configurations at higher amputation levels (e.g., shoulder) appear to be more strongly associated with prosthetic skill retention than users' cognitive status. This may be due to noncognitive user demands (e.g., device weight) statistically masking the discrete influence of cognitive status on skill retention at higher configuration levels. Neuropsychological assessment warrants consideration as a valuable tool in rehabilitation settings to assist in functional device candidacy evaluations.

Do Gait and Functional Parameters Change After Transtibial Amputation Following Attempted Limb Preservation in a Military Population?

BACKGROUND

Surgical attempts at lower limb preservation after trauma may be complicated by pain and gait disturbances, which can impact the activity level of a military service member. It is unclear how later transtibial amputation (TTA) might affect patients who elect this option after attempts at limb preservation.

QUESTIONS/PURPOSES

The purposes of the study were to compare preamputation and postamputation (1) the numeric rating scale for pain and pain medication use; (2) self-reported activity level, Four Square Step Test (FSST) results, and assistive device use; and (3) spatiotemporal variables measured with instrumented gait analysis in individuals who elected TTA after multiple attempts at limb preservation.

METHODS

Retrospective review revealed 10 patients with unilateral lower extremity injuries who underwent late TTA between 2008 and 2016. All patients had undergone multiple limb preservation attempts and had completed instrumented gait evaluations as part of their routine care before and after TTA. One patient was excluded as a result of short followup. The remaining nine patients (eight men, 29 ± 6 years) averaged five surgeries before amputation. Injuries were from improvised explosive devices (six), motorcycle accidents (two), and one training accident. Strict indications for amputation were pain, difficulties performing activities of daily living, limited physical function, and medication dependence. Data for the aforementioned purposes were collected by gait laboratory staff before and 8 to 17 months after amputation. Time to TTA after initial injury was 5 ± 3 years. At the start of the gait analysis study, pain was assessed at rest, activity level was recorded by patient report, and the FSST was administered.

RESULTS

After TTA, there was a decrease in pain scores from 4 ± 2 to 1 ± 1 and patients using narcotics decreased from four to only one patient. Self-reported walking endurance increased from 1 ± 1 mile to 7 ± 8 miles and patients able to run increased from one patient to eight with the ninth having no desire to run but bicycled. Patient FSST times improved from 12 ± 10 seconds to 5 ± 1 seconds. No patients required assistive devices after TTA. There were improvements in velocity (108 ± 16 cm/s to 142 ± 7 cm/s), stride length (129 ± 14 cm to 154 ± 8 cm), cadence (101 ± 9 steps/min to 111 ± 7 steps/min), and step width (16 ± 3 cm to 12 ± 2 cm) between pre- and postassessments. Asymmetric single-limb stance time was measured both pre- and postamputation; this did not worsen with the increase in walking velocity.

CONCLUSIONS

The findings of this study show that TTA after attempted limb preservation in a young, motivated group of service members after traumatic injuries can be successful in decreasing pain and narcotic use and can allow for high-level functional activities. Future studies will be needed to compare this cohort with patients who underwent early TTA after traumatic injury. However, we acknowledge that the resources and support structure available for this population are unique and may not be readily available to the general population.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Outcomes following limb salvage after combat hindfoot injury are inferior to delayed amputation at five years

Objectives

The surgical challenge with severe hindfoot injuries is one of technical feasibility, and whether the limb can be salvaged. There is an additional question of whether these injuries should be managed with limb salvage, or whether patients would achieve a greater quality of life with a transtibial amputation. This study aims to measure functional outcomes in military patients sustaining hindfoot fractures, and identify injury features associated with poor function.

Methods

Follow-up was attempted in all United Kingdom military casualties sustaining hindfoot fractures. All respondents underwent short-form (SF)-12 scoring; those retaining their limb also completed the American Academy of Orthopaedic Surgeons Foot and Ankle (AAOS F&A) outcomes questionnaire. A multivariate regression analysis identified injury features associated with poor functional recovery.

Results

In 12 years of conflict, 114 patients sustained 134 fractures. Follow-up consisted of 90 fractures (90/134, 67%), at a median of five years (interquartile range (IQR) 52 to 80 months).

The median Short-Form 12 physical component score (PCS) of 62 individuals retaining their limb was 45 (IQR 36 to 53), significantly lower than the median of 51 (IQR 46 to 54) in patients who underwent delayed amputation after attempted reconstruction (p = 0.0351).

Regression analysis identified three variables associated with a poor F&A score: negative Bohler’s angle on initial radiograph; coexisting talus and calcaneus fracture; and tibial plafond fracture in addition to a hindfoot fracture. The presence of two out of three variables was associated with a significantly lower PCS compared with amputees (medians 29, IQR 27 to 43 vs 51, IQR 46 to 54; p < 0.0001).

Conclusions

At five years, patients with reconstructed hindfoot fractures have inferior outcomes to those who have delayed amputation. It is possible to identify injuries which will go on to have particularly poor outcomes.

Cite this article: P. M. Bennett, T. Stevenson, I. D. Sargeant, A. Mountain, J. G. Penn-Barwell. Outcomes following limb salvage after combat hindfoot injury are inferior to delayed amputation at five years. Bone Joint Res 2018;7:131–138. DOI: 10.1302/2046-3758.72.BJR-2017-0217.R2.

Treating osteomyelitis of major limb amputations with a modified Lautenbach technique

INTRODUCTION

Major lower limb amputation significantly increases the energy cost of walking for patients. Complications such as osteomyelitis may require further surgery, and can lead to shortening of the stump. In these cases, the aim should be to treat infection without shortening the limb further. We present a series of patients with established osteomyelitis of the amputation stump, managed using a modified Lautenbach technique.

METHOD

Six patients with either above or below knee amputations, in the practice of a single orthopaedic surgeon, were studied. Ages range from 39 to 64 years, and reasons for amputation included infection, pain, and necrosis. All patients had osteomyelitis in the amputation stump confirmed on MRI.

RESULTS

At a mean follow-up of 3.75 years (range 7 months to 6 years) all six patients had no clinical or haematological evidence of infection, and had returned to independent living. Stump length was preserved in all cases, including in one patient who underwent two procedures to ensure complete debridement.

CONCLUSIONS

We believe that this case series is the largest so far published regarding this modification of the Lautenbach Procedure. This operation treats infection effectively without further loss of bone length, and no patients so far have developed significant complications.

A Unique Application of Negative Pressure Wound Therapy Used to Facilitate Patient Engagement in the Amputation Recovery Process

Amputation rates during recent military conflicts were at an all-time high, but medical treatment of those amputations and attitudes of service members to get back to duty are also surging ahead. We present the cases of an active duty rescue C130 pilot with an above-the-knee amputation and a retired army sergeant with a below-the-knee amputation. Successful rehabilitation was augmented in both cases by using negative pressure incorporated in a custom prosthetic socket to accelerate incision closure, improve self-efficacy in wound care, and self-management, ultimately leading to faster recovery times, full engagement of the rehabilitation process, and return to active duty.

Targeted Muscle Reinnervation for Transradial Amputation: Description of Operative Technique

Targeted muscle reinnervation (TMR) is a revolutionary surgical technique that, together with advances in upper extremity prostheses and advanced neuromuscular pattern recognition, allows intuitive and coordinated control in multiple planes of motion for shoulder disarticulation and transhumeral amputees. TMR also may provide improvement in neuroma-related pain and may represent an opportunity for sensory reinnervation as advances in prostheses and haptic feedback progress. Although most commonly utilized following shoulder disarticulation and transhumeral amputations, TMR techniques also represent an exciting opportunity for improvement in integrated prosthesis control and neuroma-related pain improvement in patients with transradial amputations. As there are no detailed descriptions of this technique in the literature to date, we provide our surgical technique for TMR in transradial amputations.

Rodent model for assessing the long term safety and performance of peripheral nerve recording electrodes

OBJECTIVE

In the US alone, there are approximately 185 000 cases of limb amputation annually, which can reduce the quality of life for those individuals. Current prosthesis technology could be improved by access to signals from the nervous system for intuitive prosthesis control. After amputation, residual peripheral nerves continue to convey motor signals and electrical stimulation of these nerves can elicit sensory percepts. However, current technology for extracting information directly from peripheral nerves has limited chronic reliability, and novel approaches must be vetted to ensure safe long-term use. The present study aims to optimize methods to establish a test platform using rodent model to assess the long term safety and performance of electrode interfaces implanted in the peripheral nerves.

APPROACH

Floating Microelectrode Arrays (FMA, Microprobes for Life Sciences) were implanted into the rodent sciatic nerve. Weekly in vivo recordings and impedance measurements were performed in animals to assess performance and physical integrity of electrodes. Motor (walking track analysis) and sensory (Von Frey) function tests were used to assess change in nerve function due to the implant. Following the terminal recording session, the nerve was explanted and the health of axons, myelin and surrounding tissues were assessed using immunohistochemistry (IHC). The explanted electrodes were visualized under high magnification using scanning electrode microscopy (SEM) to observe any physical damage.

MAIN RESULTS

Recordings of axonal action potentials demonstrated notable session-to-session variability. Impedance of the electrodes increased upon implantation and displayed relative stability until electrode failure. Initial deficits in motor function recovered by 2 weeks, while sensory deficits persisted through 6 weeks of assessment. The primary cause of failure was identified as lead wire breakage in all of animals. IHC indicated myelinated and unmyelinated axons near the implanted electrode shanks, along with dense cellular accumulations near the implant site. Scanning electron microscopy (SEM) showed alterations of the electrode insulation and deformation of electrode shanks.

SIGNIFICANCE

We describe a comprehensive testing platform with applicability to electrodes that record from the peripheral nerves. This study assesses the long term safety and performance of electrodes in the peripheral nerves using a rodent model. Under this animal test platform, FMA electrodes record single unit action potentials but have limited chronic reliability due to structural weaknesses. Future work will apply these methods to other commercially-available and novel peripheral electrode technologies.

Extremity War Injuries XI: Maintaining Force Readiness During an Era of Military Transition

The symposium Extremity War Injuries XI focused on issues related to the transitions in medical care that are occurring as the focus of the war on terror changes. Titled "Maintaining Force Readiness During an Era of Military Transition," this year's symposium highlighted the results of Department of Defense-funded research in musculoskeletal injury, the evolution of combat casualty care, and the readiness of the fighting force. The issues highlighted related to the force readiness of both troops and their medical support as well as the maintenance of the combat care expertise that has been developed during the last decade of conflict. As always, participants in breakout sessions addressed the research gaps in the topics discussed.

Analysis of Orthopaedic Research Produced During the Wars in Iraq and Afghanistan

BACKGROUND

Military orthopaedic surgeons have published a substantial amount of original research based on our care of combat-wounded service members and related studies during the wars in Iraq and Afghanistan. However, to our knowledge, the influence of this body of work has not been evaluated bibliometrically, and doing so is important to determine the modern impact of combat casualty research in the wider medical community.

QUESTIONS/PURPOSES

We sought to identify the 20 most commonly cited works from military surgeons published during the Iraq and Afghanistan conflicts and analyze them to answer the following questions: (1) What were the subject areas of these 20 articles and what was the 2013 Impact Factor of each journal that published them? (2) How many citations did they receive and what were the characteristics of the journals that cited them? (3) Do the citation analysis results obtained from Google Scholar mirror the results obtained from Thompson-Reuters' Web of Science?

METHODS

We searched the Web of Science Citation Index Expanded for relevant original research performed by US military orthopaedic surgeons related to Operation Iraqi Freedom and Operation Enduring Freedom between 2001 and 2014. Articles citing these studies were reviewed using both Web of Science and Google Scholar data. The 20 most cited articles meeting inclusion criteria were identified and analyzed by content domain, frequency of citation, and sources in which they were cited.

RESULTS

Nine of these studies examined the epidemiology and outcome of combat injury. Six studies dealt with wound management, wound dehiscence, and formation of heterotopic ossification. Five studies examined infectious complications of combat trauma. The median number of citations garnered by these 20 articles was 41 (range, 28-264) in Web of Science. Other research citing these studies has appeared in 279 different journals, covering 26 different medical and surgical subspecialties, from authors in 31 different countries. Google Scholar contained 97% of the Web of Science citations, but also had 31 duplicate entries and 29 citations with defective links.

CONCLUSIONS

Modern combat casualty research by military orthopaedic surgeons is widely cited by researchers in a diverse range of subspecialties and geographic locales. This suggests that the military continues to be a source of innovation that is broadly applicable to civilian medical and surgical practice and should encourage expansion of military-civilian collaboration to maximize the utility of the knowledge gained in the treatment of war trauma.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Identifying obstacles to return to duty in severely injured combat-related servicemembers with amputation

The capacity of servicemembers with amputation to return to duty after combat-related amputation and the associated disabilities remains largely unknown. The purpose of this study was to examine the disabling conditions and return to duty rates of servicemembers with amputation across all service branches following major limb amputations from September 2001 through July 2011. Pertinent medical information, military occupation status, return to duty designation, disabling conditions, and disability ratings for each servicemember were obtained from the Physical Evaluation Board Liaison Office (PEBLO). Across all service branches, 16 (2%) servicemembers were found fit for duty (Fit) and allowed to continue with their preinjury occupation. Another 103 (11%) were allowed to continue on Active Duty (COAD) in a less physically demanding role. More than half (554, 56%) were determined fully disabled (PEBLO rating > 75); the average disability rating was 73. COAD and Fit Army servicemembers had lower Injury Severity Scores than other servicemembers (17.4, p = 0.009 and 11.2, p < 0.001, respectively). Despite improvements in their care and rehabilitation, only 13% of all servicemembers with amputation are able to return to Active Duty and many have multiple disabling conditions that contribute to a very high level of disability.

Glasgow Coma Scale scores, early opioids, and 4-year psychological outcomes among combat amputees

Morphine and fentanyl are frequently used for analgesia after trauma, but there is debate over the advantages and disadvantages of these opioids. Among combat amputees, intravenous (IV) morphine (vs IV fentanyl) after injury was associated with reduced likelihood of posttraumatic stress disorder (PTSD). The previous results were based on military health diagnoses over 2 yr postinjury. The present study followed psychological diagnoses of patients with amputation for 4 yr using military and Department of Veterans Affairs health data. In-theater combat casualty records (n = 145) documented Glasgow Coma Scale (GCS) scores and/or morphine, fentanyl, or no opioid treatment within hours of injury. We found that (1) GCS scores were not significantly associated with PTSD; (2) longitudinal modeling using four (yearly) time points showed significantly reduced odds of PTSD for patients treated with morphine (vs fentanyl) across years (adjusted odds ratio = 0.40; 95% confidence interval = 0.17–0.94); (3) reduced PTSD prevalence for morphine (vs IV fentanyl; morphine = 25%, fentanyl = 59%, p < 0.05) was significant, specifically among patients with traumatic brain injury during the first 2 yr postinjury; and (4) PTSD prevalence, but not other disorders (e.g., mood), increased between year 1 (PTSD = 18%) and years 2 through 4 postinjury (PTSD range = 30%–32%).

Infection reduces return-to-duty rates for soldiers with Type III open tibia fractures

BACKGROUND

Infection is a potentially devastating complication following severe lower extremity trauma, but its impact on the outcomes of combat casualties remains unclear. We hypothesize that orthopedic infectious complications will have a negative impact on holistic patient outcome as measured by return-to-duty (RTD) and disability ratings among wounded soldiers.

METHODS

We reviewed the medical records for 115 wounded soldiers who sustained a Type III open tibia fracture and tabulated the prevalence of infectious complications. We searched the Physical Evaluation Board database to determine the disability ratings of soldiers with and without an infection and how many of each group was able to return to active duty service. The average percent disability rating and RTD rates between groups were compared using an unpaired t test and χ test, respectively.

RESULTS

Overall, 40% of our cohort had an infectious complication of their fractured limb. Twenty-one soldiers were able to RTD, while 94 could not and were medically retired. Of those medically retired, 44% had an infection. The average percent disability among soldiers with infection was 55%, compared with 47% for those who were not infected (p = 0.1407). Soldiers who experienced any type of infectious complication (p = 0.0470) and having osteomyelitis (p = 0.0335) had a lower chance of RTD compared with those who had no infection. Having a deep soft tissue infection alone showed a strong trend toward decreased RTD rate (p = 0.0558).

CONCLUSION

Infectious complications following severe lower extremity trauma significantly decrease the rate of RTD. In addition, the presence of infectious complications demonstrates a trend toward higher disability ratings in the combat wounded.

LEVEL OF EVIDENCE

Prognostic study, level III.

Biomechanical risk factors for knee osteoarthritis when using passive and powered ankle-foot prostheses

BACKGROUND

Gait compensations following transtibial amputation negatively affect sound limb loading and increase the risk of knee osteoarthritis. Push-off assistance provided by new powered prostheses may decrease the demands on the sound limb. However, their effects in a young population in the early stages of prosthetic use are still unknown. The purpose of this study was to compare limb loading between 1. passive and powered ankle-foot prostheses, 2. sound and amputated limbs, and 3. individuals with amputations in the relatively early stages of prosthetic use and controls.

METHODS

Ten young, active individuals with unilateral transtibial amputation and 10 controls underwent biomechanical gait analysis at three speeds. The peak external knee flexor and adductor moments, adductor moment's angular impulse, peak vertical ground reaction force and loading rate were calculated. Repeated measures ANOVAs compared between limbs, prostheses, and groups.

FINDINGS

The powered prosthesis did not decrease the sound limb's peak adduction moment or its impulse, but did decrease the external flexor moment, peak vertical force and loading rate as speed increased. The powered prosthesis decreased the loading rate from controls. The sound limb did not display a significantly greater risk for knee osteoarthritis than the intact limb or than controls in either device.

INTERPRETATION

In the early stages of prosthetic use, young individuals with transtibial amputation display few biomechanical risk factors for knee osteoarthritis development. However, a powered ankle-foot prosthesis still offers some benefits and may be used prophylactically to mitigate potential increases of these variables with continued prosthetic use over time.

Can an integrated orthotic and rehabilitation program decrease pain and improve function after lower extremity trauma?

BACKGROUND

Patients with severe lower extremity trauma have significant disability 2 years after injury that worsens by 7 years. Up to 15% seek late amputation. Recently, an energy-storing orthosis demonstrated improved function compared with standard orthoses; however, the effect when integrated with rehabilitation over time is unknown.

QUESTIONS/PURPOSES

(1) Does an 8-week integrated orthotic and rehabilitation initiative improve physical performance, pain, and outcomes in patients with lower extremity functional deficits or pain? (2) Is the magnitude of recovery different if enrolled more than 2 years after their injury versus earlier? (3) Does participation decrease the number considering late amputation?

METHODS

We prospectively evaluated 84 service members (53 less than and 31 > 2 years after injury) who enrolled in the initiative. Fifty-eight sustained fractures, 53 sustained nerve injuries with weakness, and six had arthritis (there was some overlap in the patients with fractures and nerve injuries, which resulted in a total of > 84). They completed 4 weeks of physical therapy without the orthosis followed by 4 weeks with it. Testing was conducted at Weeks 0, 4, and 8. Validated physical performance tests and patient-reported outcome surveys were used as well as questions pertaining to whether patients were considering an amputation.

RESULTS

By 8 weeks, patients improved in all physical performance measures and all relevant patient-reported outcomes. Patients less than and greater than 2 years after injury improved similarly. Forty-one of 50 patients initially considering amputation favored limb salvage at the end of 8 weeks.

CONCLUSIONS

We found this integrated orthotic and rehabilitation initiative improved physical performance, pain, and patient-reported outcomes in patients with severe, traumatic lower extremity deficits and that these improvements were sustained for > 2 years after injury. Efforts are underway to determine whether the Return to Run clinical pathway with the Intrepid Dynamic Exoskeletal Orthosis (IDEO) can be successfully implemented at additional military centers in patients > 2 years from injury while sustaining similar improvements in patient outcomes. The ability to translate this integrated orthotic and rehabilitation program into the civilian setting is unknown and warrants further investigation.

Initial injury severity and social factors determine ability to deploy after combat-related amputation

OBJECTIVE

While many recent publications have examined the ability of amputees to return to active duty, it remains largely unknown why few amputees deploy after amputation and many amputees do not. The purpose of this study is to examine what predictor(s) exist for whether or not an amputee will deploy after sustaining a combat-related amputation.

METHODS

All U.S. Service members who sustained major extremity amputations from September 2001 through July 2011 were analysed. Amputation level(s), mechanism of injury, time interval to amputation, age, rank, Physical Evaluation Board (PEB) disposition and ability to deploy after amputation were determined.

RESULTS

Deployment information after amputation was obtained for 953 amputees. There were 47 (5%) amputees who deployed. There were no significant differences amongst service branches for the deployment of amputees (p > 0.2). Amputees who underwent their amputation on the same day of their injury were significantly less likely to deploy after amputation than those who had their amputation on the day of injury (p = .01). Deployed amputees had significantly lower Injury Severity Scores than amputees who did not deploy (15.98 vs 20.87, p < 0.01) and officers were significantly (p < .01) more likely to deploy and the average age of amputees who deployed was significantly higher than those who did not (27.5 vs 25.1, p < .01). Lastly, those amputees who sustained a transtibial amputation were significantly more likely to deploy than all other amputation levels (p < .01). Nine out of 19 (47%) Special Forces amputees were able to deploy.

DISCUSSION

The vast majority of amputees do not able to deploy after undergoing amputation. The main predictors of deploying after sustaining a combat-related amputation appear to be: sustaining a transtibial amputation, being of senior rank or age and being a member of the Special Forces. Many of these factors appear to be non-treatment related and highlight the importance that individual and social factors play in the recovery of severe injuries.

Characterisation and outcomes of upper extremity amputations

BACKGROUND

The purpose of this study is to characterise the injuries, outcomes, and disabling conditions of the isolated, combat-related upper extremity amputees in comparison to the isolated lower extremity amputees and the general amputee population.

METHODS

A retrospective study of all major extremity amputations sustained by the US military service members from 1 October 2001 to 30 July 2011 was conducted. Data from the Department of Defense Trauma Registry, the Armed Forces Health Longitudinal Technology Application, and the Physical Evaluation Board Liaison Offices were queried in order to obtain injury characteristics, demographic information, treatment characteristics, and disability outcome data.

RESULTS

A total of 1315 service members who sustained 1631 amputations were identified; of these, 173 service members were identified as sustaining an isolated upper extremity amputation. Isolated upper extremity and isolated lower extremity amputees had similar Injury Severity Scores (21 vs. 20). There were significantly more non-battle-related upper extremity amputees than the analysed general amputation population (39% vs. 14%). Isolated upper extremity amputees had significantly greater combined disability rating (82.9% vs. 62.3%) and were more likely to receive a disability rating >80% (69% vs. 53%). No upper extremity amputees were found fit for duty; only 12 (8.3%) were allowed continuation on active duty; and significantly more upper extremity amputees were permanently retired than lower extremity amputees (82% vs. 74%). The most common non-upper extremity amputation-related disabling condition was post-traumatic stress disorder (PTSD) (17%). Upper extremity amputees were significantly more likely to have disability from PTSD, 13% vs. 8%, and loss of nerve function, 11% vs. 6%, than the general amputee population.

DISCUSSION/CONCLUSION

Upper extremity amputees account for 14% of all amputees during the Operation Enduring Freedom and Operation Iraqi Freedom conflicts. These amputees have significant disability and are unable to return to duty. Much of this disability is from their amputation; however, other conditions greatly contribute to their morbidity.

Return-to-duty rates among US military combat-related amputees in the global war on terror: job description matters

BACKGROUND

The purpose of this study was to identify the differences seen between military occupation services (MOS) in terms of amputation patterns, subsequent disabling conditions, and their ability to return to duty.

METHODS

A retrospective study of major extremity amputations sustained by US service members between October 1, 2001, and July 30, 2011, was performed. Data obtained from the amputation database, Joint Trauma Theater Database, and the Physical Evaluation Board Liaison Office included demographics, amputation location(s), Injury Severity Scores (ISSs), disabling conditions, disability ratings, and disposition status.

RESULTS

There were 1,221 major extremity amputees identified during the specified time frame, of which 899 had data regarding disabling conditions, ratings, and disposition. All service branches were represented. Personnel from the US Army (USA) Infantry were significantly (p < 0.0001) more likely to sustain an amputation than other MOS. The USA Infantry, the US Marine Corps Infantry and the USA Armor represented the top three specialties and accounted for more than 57% of all amputees. Approximately 89% of all service members did not return to duty, and the mean combined for all amputees was 76. USA Special Forces (USA SF) operators were significantly more likely to return to duty (p = 0.0022) and be found fit for duty (p = 0.0015) than all other MOS despite having a mean ISS (20) that was no different from those of other service members. No USA SF personnel were found to have posttraumatic stress disorder as a disabling condition.

CONCLUSION

All amputees, regardless of MOS, are not likely to return to active duty and especially unlikely to be found fit for duty, except for members of the USA SF. The reason(s) for the increased return to duty for USA SF personnel remains unknown but a lack of posttraumatic stress disorder may be a contributing factor.

Deployment after limb salvage for high-energy lower-extremity trauma

BACKGROUND

Many wounded warriors experienced high-energy lower-extremity trauma (HELET) that may be limb threatening. Volumetric muscle loss, posttraumatic osteoarthritis, nerve injuries, and pain may severely limit physical function. Several wounded warriors express a strong desire to return to their units and be deployed in their original military occupational specialty. We began the return-to-run (RTR) clinical pathway at our institution 2 years ago to facilitate high-performance goals such as these. It involves an energy storing ankle foot orthosis, the intrepid dynamic exoskeletal orthosis in combination with high-intensity, progression-oriented rehabilitation. We sought to determine the rate of deployment or predeployment training after participation in this noninvasive intervention.

METHODS

A retrospective analysis of the RTR database was performed to determine the rate of deployment or predeployment training among those service members who began participation in the RTR between November of 2009 and March of 2011. Medical records were reviewed for demographics, injury, surgical data, and major complications. Requests for delayed amputation were recorded, and charts were reviewed to determine if patients eventually elected to proceed with amputation or if they chose to continue with limb salvage.

RESULTS

Between November 2009 and March 2011, 87 service members completed the RTR. Of these, 17 (19.5%) have been deployed to combat or are in predeployment training. Sixteen serve in combat arms (nine Special Forces, four infantry/ranger, two combat engineers, and one gunner), and one is a member of the military intelligence community. Fifteen patients sustained their injuries as a result of HELET (four gunshot, five motor vehicle collisions, four explosions, one parachute injury, and one fall from height), one had idiopathic avascular necrosis of the talus, and one had an iatrogenic nerve injury after pelvic surgery. Six of the patients underwent circular external fixation, five received joint fusions (three ankle, two subtalar joint), and nine had major nerve injuries. Four initially desired amputation of their injured limb but have subsequently countermanded their request.

CONCLUSION

Returning to high-level physical function after HELET is challenging. After implementation of the RTR clinical pathway with the intrepid dynamic exoskeletal orthosis, 19.5% of wounded warriors treated with the RTR have been deployed or will be deployed in the coming year.

Challenges in severe lower limb injury rehabilitation

Restoration of lower limb function following severe injury is a challenge. Rehabilitation must take into account psychosocial factors and patient self-efficacy as well as functional goals. The Return to Run clinical pathway, an integrated orthotic and rehabilitation initiative, is an example of goal-oriented rehabilitation with periodic assessment aimed at restoring wounded warriors to high-level performance following severe lower extremity trauma. Objective assessment measures of surgical and rehabilitation interventions are lacking for persons with high-level performance demands, such as those required by service members. Thus, the Military Performance Laboratory at the Center for the Intrepid has established normative data for several physical performance measures, some of which are now routinely used to assess service members with severe lower extremity trauma. Patient expectations of treatment and rehabilitation are high and must be met to avoid poor outcomes attributed to nonanatomic factors.

Outcomes in lower limb amputation following trauma: a systematic review and meta-analysis

INTRODUCTION

Lower limb amputation (LLA) is life-changing surgery. Shorter residual limbs are known to place greater physiological strain on patients than longer residual limbs; however, there is ongoing debate as to whether through-knee amputations are preferable to above-knee amputations. This analysis aims to resolve this question by systematically collecting and pooling published and unpublished data on this subject.

METHODS

An exhaustive search of Medline, Embase and Recal databases was made for outcome studies of patients with lower limb amputations following trauma. Studies concerned with amputations of the upper limb or foot and ankle were excluded as were papers reporting outcomes in a population of mixed trauma and non-trauma patients. Authors of studies published in the last 10 years were contacted for unpublished details. Patients were then divided, according to amputation height, into four groups: below-knee amputation (BKA), through-knee amputation (TKA), above-knee amputation (AKA) and bilateral amputation. The primary outcome measure was Physical Component Score (PCS) of the short-form-36 measure of quality of life and secondary outcomes were pain, employment, ability to walk 500m and proportion of time that prosthesis is worn.

RESULTS

As many as 27 studies were included, representing a total of 3105 patients, 1855 with a BKA, 104 with a TKA, 888 with an AKA and 258 bilateral amputees. There was progressive and significant lowering of PCS (worsening outcomes) as unilateral amputation height became more proximal from BKA to TKA and AKA. A significantly greater proportion of patients with a BKA or a TKA were able to walk 500m than those with an AKA or bilateral amputation (p=0.0035). However, patients with a TKA wore their prosthesis significantly less, and had significantly more pain than those with an AKA.

CONCLUSION

This study describes the impact of LLA of different levels on patients' lives. The results indicate that patients with a TKA have a better physical quality of life than those with an AKA and, therefore, support the surgical strategy of maintaining maximum length and performing TKA in preference to AKA, where possible.

The outcome of British combat amputees in relation to military service

BACKGROUND

The study aim was to determine the outcome, in relation to military service in UK military combat amputees.

PATIENTS AND METHODS

Casualties were assessed at mean 2.4 years after injury and graded by a Functional Activity Assessment (FAA) ranging from 1 (fully fit) to 5 (unfit all duties) to score vocational functional outcome. ISS were calculated and the patients were categorised as having unilateral or multiple amputations. The Short Form-36 Health Survey (SF-36) was completed.

RESULTS

Of the 52, 8 patients had left the forces by medical discharge, with 44 continuing to serve. 33 of the 44 had returned to work. 50 patients had FAA grades and were at least 7.6 months post-injury. No patients were graded as FAA1, 8 as FAA2, 18 as FAA3, 19 as FAA4 and 5 as FAA5. There was a trend for the FAA score to increase with injury severity, as measured by ISS i.e. vocational functional outcome was worse with more severe injuries, although this did not reach statistical significance (p=0.095). Multiple amputee patients had significantly higher FAA grades (p<0.001) and were all FAA 4 or 5. Of the 33 patients who had returned to work, 8 were FAA2, 12 FAA3 and 12 FAA4. The mean SF-36 scores for Physical Component Summary (PCS) increased significantly from 36.4 to 43.4 (p=0.001) with rehabilitation, while Mental Component Summary (MCS) was 53.0 and remained similar at 53.6 (p=0.987). MCS scores were similar in these patients to the normal population, 50 (SD 10).

CONCLUSIONS

This study is the first to report the outcomes, with regards to return to work, of the UK military amputees injured in Afghanistan and Iraq Soldiers are surviving more severe and complex injuries than before and the majority are able to return successfully to military work. SF-36 PCS scores improve significantly with rehabilitation, and while MCS scores remain constant, the initial assessments are comparable with a normal population.