Peak tibial axial acceleration during walking is related to intact-side lower limb pain in persons with unilateral transtibial amputation.

BACKGROUND: Persons who undergo unilateral transtibial amputation are at an increased risk of secondary musculoskeletal joint pain and degeneration, which has been linked to excessive loading rates of the intact-side limb. Tibial axial acceleration, a feasible measure of loading rates with wearable sensors, would be clinically useful to relate to joint pain in persons with unilateral transtibial amputation. RESEARCH QUESTION: What is the relationship between peak tibial axial accelerations and intact-side joint pain in persons with unilateral transtibial amputation during walking? METHODS: Persons with unilateral transtibial amputation (n = 51) were separated into two groups based on the presence of intact-side limb pain (with pain: n = 16; without pain: n = 35). Tibial axial accelerations were measured with bilateral shank-mounted IMUs while participants completed three 10-meter walk tests. Peak tibial axial accelerations for each limb and between-limb symmetry were compared between groups using analysis of co-variance; significance was set at 0.05. RESULTS: Between persons with vs. without intact-side limb pain, peak tibial axial accelerations were smaller on the prosthetic side (0.64 vs. 0.81 g; p = 0.04), similar on the intact side (0.82 vs. 0.79 g; p = 0.53), and more asymmetrical between sides (intact > prosthetic) (0.81 vs. 1.03 g; p = 0.01). SIGNIFICANCE: Symmetry in peak tibial axial acceleration can assist with identifying preferential limb loading during walking and, with future research, could serve as a useful clinical target for intact-side limb unloading strategies to help mitigate secondary musculoskeletal pain in persons with unilateral transtibial amputation.

General and Pain-Associated Psychological Distress Phenotypes Among Patients With Low Back Pain in the Military Health System.

OBJECTIVE: The primary objective was to describe rates of general and pain-related psychological distress for individuals with low back pain (LBP) in the Military Health System (MHS). We identified common phenotypes defined by rates of general and pain-related psychological distress and compared phenotypes on their level of pain interference, physical function, anxiety, and depression. METHODS: We created a cohort from two completed trials assessing nonpharmacological treatment for LBP in the MHS (n = 510 total). The Optimal Screening for Prediction of Referral and Outcome Yellow Flag assessment tool identified the presence of 11 different yellow flags. Latent class analysis (LCA) used yellow flag indicators to identify common psychological phenotypes. We then compared Patient-Reported Outcomes Measurement Information Systems measures of pain interference, physical function, sleep disturbance, depression, and anxiety across phenotypes. RESULTS: LCA identified five phenotypes (percentage of the sample): low distress (32%), high distress (27%), poor pain coping and low self-efficacy (18%), low self-efficacy and acceptance (14%), and poor pain coping (10%). Highly distressed phenotypes reported higher levels of pain interference, sleep disturbance, depression, and anxiety than those with other phenotypes, whereas the low distress phenotype had significantly lower pain interference and higher physical function scores than those characterized by all other phenotypes. CONCLUSION: These phenotypes provide opportunities for clinicians and researchers to develop novel LBP treatment pathways tailored to patients with different profiles of psychological distress. Future work is needed to validate their predictive capabilities for clinical outcomes.

Foot Strike Run Retraining for Patients With Patellofemoral Chondral Defects: A Case Series.

Military service members (SMs) demonstrate high rates of patellofemoral chondral defects (PFCDs) that are difficult to diagnosis and, if untreated, result in a cascade of events eventually leading to osteoarthritis. Running is an essential occupational task for SMs; however, there is little evidence regarding techniques to maintain running ability in individuals with cartilage defects. The purpose of this case series was to assess the clinical application of foot strike run retraining in patients with PFCDs. This case series included two active duty U.S. Marine Corps SMs who presented to outpatient physical therapy with PFCD, diagnosed via MRI. Both patients attended eight foot strike run retraining sessions. Running mechanics and patient-reported outcomes were recorded pre-training, post-training, and at a 1-month follow-up visit. Both patients successfully converted their strike pattern from a rearfoot to a non-rearfoot strike pattern with training and retained this strategy at 1-month follow-up. Post-intervention, both patients demonstrated increased running tolerance, and improvements in Numeric Pain Rating Scale and Lower Extremity Functional Scale scores. Biomechanical analysis showed that both patients demonstrated a 63% to 70% reduction in average and peak vertical ground reaction force loading rates post-treatment. Modification of foot strike pattern from rear to non-rearfoot strike during running for individuals with PFCD can reduce the magnitude of impact loading, which potentially limits disease progression. These findings suggest that foot strike run retraining may be a feasible strategy to reduce pain and improve function in SMs with PFCD who are required to run for occupational responsibilities.

The Influence of Active, Passive, and Manual Therapy Interventions for Low Back Pain on Opioid Prescription and Health Care Utilization.

OBJECTIVE: The aim of this study was to explore associations between the utilization of active, passive, and manual therapy interventions for low back pain (LBP) with 1-year escalation-of-care events, including opioid prescriptions, spinal injections, specialty care visits, and hospitalizations. METHODS: This was a retrospective cohort study of 4827 patients identified via the Military Health System Data Repository who received physical therapist care for LBP in 4 outpatient clinics between January 1, 2015 and January 1, 2018. One-year escalation-of-care events were evaluated based on type of physical therapist interventions (ie, active, passive, or manual therapy) received using adjusted odds ratios. RESULTS: Most patients (89.9%) received active interventions. Patients with 10% higher proportion of visits that included at least 1 passive intervention had a 3% to 6% higher likelihood of 1-year escalation-of-care events. Similarly, with 10% higher proportion of passive to active interventions used during the course of care, there was a 5% to 11% higher likelihood of 1-year escalation-of-care events. When compared to patients who received active interventions only, the likelihood of incurring 1-year escalation-of-care events was 50% to 220% higher for those who received mechanical traction and 2 or more different passive interventions, but lower by 50% for patients who received manual therapy. CONCLUSION: Greater use of passive interventions for LBP was associated with elevated odds of 1-year escalation-of-care events. In addition, the use of specific passive interventions such as mechanical traction in conjunction with active interventions resulted in suboptimal escalation-of-care events, while the use of manual therapy was associated with more favorable downstream health care outcomes. IMPACT: Physical therapists should be judicious in the use of passive interventions for the management of LBP as they are associated with greater likelihood of receiving opioid prescriptions, spinal injections, and specialty care visits.

Post-Traumatic Osteoarthritis, Psychological Health, and Quality of Life After Lower Limb Injury in U.S. Service Members.

INTRODUCTION: The aims of this project were to assess (1) the prevalence and timing of post-traumatic osteoarthritis (PTOA) after a traumatic lower limb injury, (2) the risk of PTOA based on injury type, and (3) the association of PTOA with psychological health and quality of life (QoL). MATERIALS AND METHODS: The Wounded Warrior Recovery Project (WWRP) database and the Expeditionary Medical Encounters Dataset were queried to identify service members injured during deployment. The Military Health System Data Repository was utilized to extract medical record data to identify individuals with PTOA. Data on PTSD, depression symptoms, and QoL were extracted from the WWRP. RESULTS: Of the 2,061 WWRP participants with lower limb injuries, 124 (6%) were diagnosed with PTOA, with first PTOA diagnosis occurring 3.8 ± 3.1 years after injury. Of the injury categories identified, only fractures were associated with high odds of lower limb PTOA (adjusted odds ratio [OR] = 3.92, 95% confidence interval [CI]: 2.38, 6.44). Individuals with PTOA diagnoses reported lower QoL scores relative to those without PTOA (F(1,2057) = 14.21, B = -0.05, P < .05). Additionally, rates of PTSD and depression symptoms were high but not different between those with or without PTOA. CONCLUSIONS: Despite a low prevalence of lower limb PTOA in our study, fractures increased the risk of PTOA after deployment-related injuries. Additionally, those with PTOA reported lower QoL scores relative to those without PTOA. The findings of this study highlight the personalized needs of patients with trauma beyond just the repair of the immediate injury.

Rearfoot Strike Run Retraining for Achilles Tendon Pain: A Two-patient Case Series.

INTRODUCTION: Running-related injuries are prevalent in the military and are often related to physical fitness test training. Non-rearfoot striking while running is known to increase the risk of Achilles tendon injuries because of the high eccentric energy absorption by the elastic components of the planarflexor muscle-tendon complex. However, there is limited evidence to suggest benefits of converting runners with Achilles tendon pain to use a rearfoot strike. METHODS: This is a case series of two active-duty Service members with chronic, running-related Achilles tendon pain that utilized a natural non-rearfoot strike pattern. Both patients were trained to utilize a rearfoot strike while running through the use of real-time visual feedback from wearable sensors. RESULTS: The trained rearfoot strike pattern was retained for over one month after the intervention, and both patients reported improvements in pain and self-reported function. CONCLUSIONS: This case series demonstrated the clinical utility of converting two non-rearfoot strike runners to a rearfoot strike pattern to decrease eccentric demands on the plantarflexors and reduce Achilles tendon pain while running.

Principal components analysis of postural sway in persons with unilateral lower limb amputation: A wearable sensor approach.

Standing sway assessments can detect sensory imbalances which compromise postural control. Persons with lower limb amputation (LLA) often demonstrate impaired postural control, increasing fall risk. Here, principal features of postural sway were identified in persons with unilateral LLA using a single, commercially available wearable sensor. Sixty-one persons with LLA (n = 44 transtibial; n = 17 transfemoral) stood on a firm surface with eyes open/closed while wearing a single accelerometer mounted over the sacrum. Common parameters quantified spatiotemporal and spectral features of sway in anterior-posterior (AP) and mediolateral (ML) directions. Principal component (PC) dimensionality reduction was applied and loadings inspected to identify a reduced, non-redundant set among 14 original variables capturing 90 % variance. Six PCs described ≥ 90 % variance, with the first 3 explaining 75 %. With eyes open and closed, PC1 was loaded by variables characterizing trajectory planar size: area, jerk (i.e., sway smoothness), AP/ML RMS path distance, and AP/ML path range. With eyes open, PC2 was loaded by variables characterizing direction and spectral features: ellipse rotation, AP centroidal frequency, and ML jerk. With eyes closed, PC2 spectral loadings increased: ML centroidal frequency, ML frequency dispersion, and AP centroidal frequency. With eyes open, PC3 was loaded by ellipse rotation, jerk, ML velocity, ML centroidal frequency. With eyes closed, PC3 was loaded by ellipse rotation, ML centroidal frequency, ML frequency dispersion, and AP path velocity, characterizing off-axis error/corrections. RMS of path distance, ellipse rotation, centroidal frequency, frequency dispersion, path velocity, and jerk are a concise parameter set, derived from an accelerometer, to capture principal sway features in persons with LLA during standing balance with visual perturbations.

The association between kinesiophobia and functional limitations in service members with knee pain.

BACKGROUND: Knee diagnoses account for more than 50% of lower extremity musculoskeletal conditions in non-deployed US Service members. However, there is limited information regarding kinesiophobia in Service members with non-operative knee diagnoses. HYPOTHESES: The objectives of this study were to determine the prevalence of high levels of kinesiophobia in US military Service members with knee pain across different knee diagnoses, and to determine the relationships between kinesiophobia and lower extremity function and/or specific functional limitations in Service members with knee pain. It was hypothesized Service members with knee pain would exhibit high levels of kinesiophobia across all knee diagnoses examined, and higher levels of both kinesiophobia and pain would be associated with worse self-reported function in this population. It was also hypothesized higher levels of kinesiophobia would be associated with functional activities with high knee loading. DESIGN: Retrospective cohort study. LEVEL OF EVIDENCE: IV. METHODS: Sixty-five US Service members presenting to an outpatient physical therapy clinic were included in this study (20 females; age = 30.8 ± 7.7 years; height = 1.74 ± 0.9 m; mass = 80.7 ± 16.2 kg). Inclusion criterion was the presence of knee pain (duration = 50 ± 59 months); exclusion criterion was knee pain as a sequela of knee surgery. Data regarding demographic, pain chronicity, pain by Numeric Rating Scale (NRS), Tampa Scale of Kinesiophobia (TSK), and Lower Extremity Functional Scale (LEFS) were retrospectively obtained from patients' medical records. A high level of kinesiophobia was defined as a TSK score of greater than 37 points. Patient diagnoses included: osteoarthritis (n = 16); patellofemoral pain syndrome (n = 23); and other non-operative knee diagnoses (n = 26). Commonality analysis was utilized to determine the effects of age, height, mass, NRS, and TSK on LEFS score. Predictor values were interpreted as <1% = negligible, >1% = small; >9% = moderate, >25% = large. Additionally, exploratory item-specific analyses examined the strength of the relationships between kinesiophobia and LEFS item responses. Binary logistic regression determined if difficulty with an individual LEFS item could be predicted from either NRS or TSK score. Statistical significance was set at P < 0.05. RESULTS: High levels of kinesiophobia were identified in 43 individuals (66%). NRS and TSK explained 19.4% and 8.6% of the unique variance in LEFS, and 38.5% and 20.5% of total variance, respectively. Age, height, and mass explained negligible to small proportions of the unique variance in LEFS. TSK and NRS were independent predictors for 13/20 individual LEFS items, with odds ratios ranging from 1.12 to 3.05 (P < 0.05). CONCLUSION: The majority of US Service members in this study exhibited high levels of kinesiophobia. Kinesiophobia was significantly related to self-reported functional scores and performance on individual functional tasks in Service members with knee pain. CLINICAL RELEVANCE: Treatment strategies addressing both fear of movement and pain reduction in patients with knee pain may help optimize functional outcomes.

Weight Changes in Young Service Members After Lower Limb Amputation: Insights From Group-Based Trajectory Modeling.

INTRODUCTION: Weight gain can contribute to osteoarthritis, cardiovascular disease, low back pain, and poor health-related quality of life. Weight trajectory patterns have been described in older veterans with limb loss; however, there is limited evidence of changes in weight in younger veterans with limb loss. MATERIALS AND METHODS: Service members with unilateral or bilateral lower limb amputations (LLAs) (and without an upper limb amputation) were included in this retrospective cohort analysis (n = 931). The mean postamputation baseline weight was 78.0 ± 14.1 kg. Bodyweight and sociodemographic data were extracted from clinical encounters within electronic health records. Group-based trajectory modeling assessed weight change patterns 2 years postamputation. RESULTS: Three weight change trajectory groups were identified: 58% (542 of 931) of the cohort had stable weight, 38% (352 of 931) had weight gain (mean gain = 19.1 kg), and 4% (31 of 931) had weight loss (mean loss = 14.5 kg). Individuals with bilateral amputations were more frequently noted in the weight loss group compared with those with unilateral amputations. Individuals with LLAs because of trauma other than blasts were more frequently found in the stable weight group compared with those with amputations because of disease or a blast. Younger individuals (<20 years old) with amputations were more likely to be in the weight gain group compared with older individuals. CONCLUSIONS: More than half the cohort maintained a stable weight for two years after amputation, and more than a third experienced weight gain during the same time frame. Knowledge of underlying factors that were associated with weight gain could inform preventative strategies for young individuals with LLAs.

Relationship between phantom limb pain, function, and psychosocial health in individuals with lower-limb loss.

INTRODUCTION: The adverse influence of chronic pain on function and psychological health in the general population is well understood. However, the relationship between phantom limb pain (PLP) after limb loss with function and psychological health is less clear. The study purpose was to assess the influences of PLP presence and intensity on function and psychosocial health in individuals with lower-limb loss (LLL). METHODS: One hundred two individuals with major LLL completed a study-specific questionnaire on the presence and intensity of their PLP. The Patient-Reported Outcomes Measurement Information System -29 questionnaire was also administered. RESULTS: Of 102 participants, 64% reported PLP, with a mean intensity of 4.8 ± 2.3 out of 10. Individuals with vs. without PLP demonstrated significantly greater sleep disturbances ( p = 0.03), whereas the differences in function, fatigue, pain interference, depressive symptoms, anxiety, or ability to participate in social roles and activities were not statistically different between groups ( p > 0.05). Of note, mean scores for many of the Patient-Reported Outcomes Measurement Information System-29 short forms among the current sample were similar to the mean of the general population, minimizing the potential clinical impact of PLP on these domains. CONCLUSIONS: Our findings indicate a lack of meaningful associations between PLP presence or intensity with function, and psychosocial health among individuals with LLL. These findings conflict with previous research suggesting an adverse relationship between PLP, function, and psychosocial health after limb loss.

Comparison of clinical and biomechanical characteristics between individuals with lower limb amputation with and without lower back pain: A systematic review and meta-analysis.

BACKGROUND: Lower back pain is a debilitating condition common to individuals with lower limb amputation. It is unclear what risk factors contribute to the development of back pain. This study systematically reviewed and analyzed the available evidence regarding the clinical and biomechanical differences between individuals with amputation, with and without lower back pain. METHODS: A literature search was conducted in PubMed, Web of Science, Scopus, and CINAHL databases in November 2020 and repeated in June 2021 and June 2022. Studies were included if they reported comparisons of demographic, anthropometric, biomechanical, and other clinical variables between participants with and without LBP. Study quality and potential for reporting bias were assessed. Meta-analyses were conducted to compare the two groups. FINDINGS: Thirteen studies were included, with aggregated data from 436 participants (239 with LBP; 197 pain free). The median reporting quality score was 37.5%. The included studies enrolled participants who were predominantly male (mean = 91.4%, range = 77.8-100%) and with trauma-related amputation. Meta-analyses showed that individuals with LBP exhibited moderate (3.4 out of 10) but significantly greater pain than those without LBP. We found no between-group differences in age, height, weight, BMI, and time since amputation (p = 0.121-0.682). No significant differences in trunk/pelvic kinematics during gait were detected (p = 0.07-0.446) between the groups. INTERPRETATION: Demographic, anthropometric, biomechanical, and simple clinical outcome variables may be insufficient for differentiating the risk of developing back pain after amputation. Investigators should be aware of the existing gender bias in sampling and methodological limitations, as well as to consider incorporating psychosocial measures when studying LBP in this clinical population.

Development of overuse musculoskeletal conditions after combat-related upper limb amputation: a retrospective cohort study.

STUDY DESIGN: Retrospective cohort study INTRODUCTION: Service members who have sustained traumatic amputations are typically young and otherwise healthy. Beyond standard care, these individuals desire long, highly active, and relatively pain-free lifestyle, whether that is returning to active duty or transitioning to civilian life. Development of overuse musculoskeletal conditions could have a significant influence on quality of life for Service members with traumatic upper limb amputation. PURPOSE OF THE STUDY: Compare one-year incidence of overuse musculoskeletal injuries in Service members with different levels of combat-related upper limb amputation to Service members with minor combat-related upper limb injuries. METHODS: Service members with deployment-related upper limb injury (N = 519), 148 major upper limb amputation (55 with amputation at or above elbow, 93 with amputation below elbow) and 371 minor upper limb injury were included in the study. Outcomes of interest clinical diagnosis codes associated with overuse conditions of the upper limb, neck and upper back, lower limb, low back pain, and all regions combined, one year before and one year after injury. RESULTS: Overall, the one-year incidence of developing at least one musculoskeletal overuse condition after upper limb amputation was between 60% and 65%. Service members with upper limb amputations were 2.7 to 4.7 times more likely to develop an overuse upper limb condition, 3.6 to 3.8 times more likely to develop a neck and upper back condition, 2.8 to 4.4 times more likely to develop a lower limb condition, and 3.3 to 3.9 times more likely to develop low back pain as compared those who sustained minor combat-related injuries. No significant differences in the odds of developing a musculoskeletal condition was found between the above elbow and below elbow amputation groups. CONCLUSIONS: Incidence of secondary overuse conditions is elevated in Service members with upper limb amputation and warrants focused research efforts toward preventative and rehabilitative interventions.

Uneven Treadmill Training for Rehabilitation of Lateral Ankle Sprains and Chronic Ankle Instability: Protocol for a Pragmatic Randomized Controlled Trial.

BACKGROUND: Lateral ankle sprains (LASs) are common injuries among military service members. Approximately 40% of individuals with an LAS progress to develop chronic ankle instability (CAI), a condition that results in substantial mechanical and neurophysiological impairment and activity limitation. Since proprioceptive and balance training improve functional outcomes and prevent secondary injury following LAS, they are recommended in clinical practice. Uneven treadmills are an innovative modality that challenge the sensorimotor system while performing an ecologically valid task simulating environments frequently encountered by service members with LAS and CAI. OBJECTIVE: The aim of this study is to evaluate whether the inclusion of uneven treadmill training in standard rehabilitation can improve clinical, functional, biomechanical, and patient-reported outcomes compared with the standard of care alone in service members with LAS and CAI. The prophylactic effects of treatment on secondary injury and identification of any contributing or mediating factors that influence outcomes following treatment will also be evaluated. We hypothesize that service members receiving uneven treadmill training will demonstrate greater improvements in clinical and instrumented measures of impairment, patient-reported function, and lower risk of injury recurrence than the control group immediately post and 18 months following treatment. METHODS: A multisite, parallel randomized clinical trial will be performed among service members aged 18-49 years being treated for LAS and CAI in military treatment facilities in the United States. Participants randomly assigned and allocated to receive the experimental intervention will be provided up to 12 sessions of training on an uneven terrain treadmill over a 6-week treatment course to supplement standard rehabilitation care. Treatment intensity of the rehabilitation exercises and treadmill training will be progressed on the basis of patient-perceived intensity and treatment responses. Outcome measures will include patient-reported outcomes, functional assessments, performance measures, and biomechanical measures. Investigators collecting outcome measures will be blinded to treatment allocation. Reinjury rates and patient-reported outcomes of function will be tracked over 18 months following treatment. RESULTS: The project was funded in September 2020. Patient recruitment began in November 2021, with 3 participants enrolled as of February 2022. Dissemination of the main study findings is anticipated in 2024. CONCLUSIONS: This study will assess the impact of an innovative uneven-terrain treadmill on treatment outcomes in the rehabilitation of service members with LAS and CAI. The results of this study will be used to inform rehabilitation practices and to potentially improve functional outcomes and secondary prevention in this patient population. TRIAL REGISTRATION: ClinicalTrials.gov NCT04999904; https://clinicaltrials.gov/ct2/show/NCT04999904?term=NCT04999904. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/38442.

TIDieR-telehealth: precision in reporting of telehealth interventions used in clinical trials - unique considerations for the Template for the Intervention Description and Replication (TIDieR) checklist.

BACKGROUND: Recent international health events have led to an increased proliferation of remotely delivered health interventions. Even with the pandemic seemingly coming under control, the experiences of the past year have fueled a growth in ideas and technology for increasing the scope of remote care delivery. Unfortunately, clinicians and health systems will have difficulty with the adoption and implementation of these interventions if ongoing and future clinical trials fail to report necessary details about execution, platforms, and infrastructure related to these interventions. The purpose was to develop guidance for reporting of telehealth interventions. METHODS: A working group from the US Pain Management Collaboratory developed guidance for complete reporting of telehealth interventions. The process went through 5-step process from conception to final checklist development with input for many stakeholders, to include all 11 primary investigators with trials in the Collaboratory. RESULTS: An extension focused on unique considerations relevant to telehealth interventions was developed for the Template for the Intervention Description and Replication (TIDieR) checklist. CONCLUSION: The Telehealth Intervention guideline encourages use of the Template for the Intervention Description and Replication (TIDieR) checklist as a valuable tool (TIDieR-Telehealth) to improve the quality of research through a reporting guide of relevant interventions that will help maximize reproducibility and implementation.

Low back pain influences trunk-lower limb joint coordination and balance control during standing in persons with lower limb loss.

BACKGROUND: Balance is sustained through multi-joint coordination in response to postural perturbations. Low back pain alters postural responses; however, it is unknown how coordination between the trunk and lower extremities affects center of mass control during standing balance among persons with limb loss, particularly those with back pain. METHODS: Forty participants with unilateral lower limb loss (23 with back pain) stood with eyes open and closed on a firm surface, while wearing IMUs on the sternum, pelvis, and bilaterally on the thigh, shank, and foot. A state-space model with Kalman filter calculated sagittal trunk, hip, knee, and ankle joint angles. Fuzzy entropy quantified center of mass variability of sagittal angular velocity at the sacrum. Normalized cross-correlation functions identified coordination patterns (trunk-hip, trunk-knee, trunk-ankle). Multiple linear regression predicted fuzzy entropy from cross-correlation values for each pattern, with body mass and amputation level as covariates. FINDINGS: With eyes open, trunk-lower limb joint coordination on either limb did not predict fuzzy entropy. With eyes closed, positive trunk-hip coordination on the intact limb predicted fuzzy entropy in the pain group (p = 0.02), but not the no pain group. On the prosthetic side, inverse trunk-hip coordination patterns predicted fuzzy entropy in pain group (p = 0.03) only. INTERPRETATION: Persons with limb loss and back pain demonstrated opposing coordination strategies between the lower limbs and trunk when vision was removed, perhaps identifying a mechanism for pain recurrence. Vision is the dominant source of balance stabilization in this population, which may increase fall risk when visual feedback is compromised.

Ankle sprain bracing solutions and future design consideration for civilian and military use.

INTRODUCTION: Ankle sprains are common injuries within the civilian and military populations, with lingering symptoms that include pain, swelling, giving-way, and a high likelihood for recurrence. Numerous bracing systems are available to stabilize the ankle joint following sprains, with new design iterations frequently entering the market. Currently available braces generally include sleeve, lace-up, and stirrup designs. Sleeves provide mild compression and warmth but limited stability for the ankle, while lace-ups and stirrups appear to be more effective at preventing and treating lateral ankle sprains. AREAS COVERED: This review summarizes the use of various brace options in practice. Their major clinical benefits, and limitations are highlighted, followed by an overview of emerging concepts in brace design. Current advancements in biomechanical simulation, multifunctional material fabrication, and wearable, field-deployed devices for human injury surveillance are discussed, providing possibilities for conceiving new design concepts for next-generation smart ankle braces. EXPERT OPINION: Performance of the commercially available braces are limited by their current design concepts. Suggestions on future brace design include: (1) incorporating high-performance materials suitable for extreme environments, (2) leveraging modeling and simulation techniques to predict mechanical support requirements, and (3) implementing adaptive, customizable componentry material to meet the needs of each unique patient.

Optimizing the Impact of Pragmatic Clinical Trials for Veteran and Military Populations: Lessons From the Pain Management Collaboratory.

Pragmatic clinical trials (PCTs) are well-suited to address unmet healthcare needs, such as those arising from the dual public health crises of chronic pain and opioid misuse, recently exacerbated by the COVID-19 pandemic. These overlapping epidemics have complex, multifactorial etiologies, and PCTs can be used to investigate the effectiveness of integrated therapies that are currently available but underused. Yet individual pragmatic studies can be limited in their reach because of existing structural and cultural barriers to dissemination and implementation. The National Institutes of Health, Department of Defense, and Department of Veterans Affairs formed an interagency research partnership, the Pain Management Collaboratory. The partnership combines pragmatic trial design with collaborative tools and relationship building within a large network to advance the science and impact of nonpharmacological approaches and integrated models of care for the management of pain and common co-occurring conditions. The Pain Management Collaboratory team supports 11 large-scale, multisite PCTs in veteran and military health systems with a focus on team science with the shared aim that the "whole is greater than the sum of the parts." Herein, we describe this integrated approach and lessons learned, including incentivizing all parties; proactively offering frequent opportunities for problem-solving; engaging stakeholders during all stages of research; and navigating competing research priorities. We also articulate several specific strategies and their practical implications for advancing pain management in active clinical, "real-world," settings.

Sensitivity of a Subject-specific Ankle Sprain Simulation to Extrinsic Versus Intrinsic Biomechanical Factors.

Ankle sprains are the most common musculoskeletal injury in sport and military activity, despite existing prophylactic strategies. The purpose of this report was to develop a probabilistic simulation of lateral ankle sprains during single-limb drop landing, towards accelerating innovation in ankle sprain prevention. A deterministic, subject-specific musculoskeletal model was extended with automation and probabilistic distributions on sprain-related biomechanical factors. Probabilistic simulations were generated using traditional Monte Carlo techniques and the advanced mean value method, a more computationally-efficient approach. Predicted distributions of peak ankle joint rotations, velocities, and moments borne by supporting passive structures agreed favorably with the deterministic model and with reports of real sprain biomechanics. Parameter sensitivities identified that predictions were most strongly influenced by drop height, subtalar joint posture at contact, invertor/evertor co-activation, and passive ankle stiffness. The advanced mean value method predicted confidence bounds comparable to a 1000-trial Monte Carlo simulation, and required only 14 model evaluations and 4-min processing time. The extended probabilistic simulation may be useful to virtually test new prophylactic strategies for ankle sprains, and is made available for open-source use (https://simtk.org/projects/sprain-sim).