This Viewpoint discusses a report from the National Academies of Sciences, Engineering, and Medicine on aligning therapeutic investment with unmet need to better serve the health of the US public.

Background:This study compared outcomes at 18 months between patients who underwent transtibial amputation with and without a tibiofibular synostosis procedure. We hypothesized that complication rates would be lower in patients who did not receive a synostosis procedure compared with those who did receive a synostosis procedure, but the synostosis group would report better function.Methods:This multicenter randomized clinical trial (RCT) included patients aged 18 to 60 years who were treated without (n = 52) or with synostosis (n = 54) during transtibial amputation. Patients who refused randomization were enrolled in an observational (OBS) study (n = 93; 31 synostosis, 62 non-synostosis). There were 2 primary outcomes: operative treatment for a complication within 18 months of amputation and Short Musculoskeletal Function Assessment (SMFA) scores. The primary analyses were based on the RCT participants, and the secondary analyses were based on the treatment received by the combined RCT + OBS participants.Results:In the primary RCT analysis, the probability of >= 1 operatively treated complication was higher for the synostosis group (42%; 95% confidence interval [CI]: 29.8% to 56.2%) than the non-synostosis group (24%; 95% CI: 14.2% to 37.9%), with an absolute risk difference of 18% (95% CI: 0.31% to 36%). There were no appreciable differences in mean SMFA scores. In the secondary combined analysis, the probability of an operatively treatment complication was larger in patients who did versus did not receive a synostosis procedure (absolute risk difference: 26.1%; 95% CI: 12.0% to 40.3%). Differences in SMFA scores favored synostosis, although there were no differences in pain, prosthetic use, and satisfaction.Conclusions:The results of the primary RCT analysis supported our hypothesis of fewer complications in patients who do not undergo a synostosis procedure compared with those who undergo a synostosis procedure, but we found insufficient evidence to conclude that those in the synostosis group have better function. The trial did not reach target enrollment. The secondary combined analysis supported the primary analysis in terms of complications. In the secondary analysis, while pain, prosthetic use, and satisfaction remained similar, the SMFA scores were better for the patients who received a synostosis procedure, although the differences are of uncertain clinical importance.Level of Evidence:Therapeutic Level I. See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND:The Short Musculoskeletal Function Assessment (SMFA) is a well validated, widely used patient-reported outcome (PRO) measure for orthopaedic patients. Despite its widespread use and acceptance, this measure does not have an agreed upon minimal clinically important difference (MCID). The purpose of the present study was to create distributional MCIDs with use of a large cohort of research participants with severe lower extremity fractures. METHODS:Three distributional approaches were used to calculate MCIDs for the Dysfunction and Bother Indices of the SMFA as well as all its domains: (1) half of the standard deviation (one-half SD), (2) twice the standard error of measurement (2SEM), and (3) minimal detectable change (MDC). In addition to evaluating by patient characteristics and the timing of assessment, we reviewed these calculations across several injury groups likely to affect functional outcomes. RESULTS:A total of 4,298 SMFA assessments were collected from 3,185 patients who had undergone surgical treatment of traumatic injuries of the lower extremity at 60 Level-I trauma centers across 7 multicenter, prospective clinical studies. Depending on the statistical approach used, the MCID associated with the overall sample ranged from 7.7 to 10.7 for the SMFA Dysfunction Index and from 11.0 to 16.8 for the SMFA Bother Index. For the Dysfunction Index, the variability across the scores was small (<5%) within the sex and age subgroups but was modest (12% to 18%) across subgroups related to assessment timing. CONCLUSIONS:A defensible MCID can be found between 7 and 11 points for the Dysfunction Index and between 11 and 17 points for the Bother Index. The precise choice of MCID may depend on the preferred statistical approach and the population under study. While differences exist between MCID values based on the calculation method, values were consistent across the categories of the various subgroups presented. LEVEL OF EVIDENCE:Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND:The purpose of this study was to compare 18-month clinical and patient-reported outcomes between patients with severe lower-limb injuries treated with a transtibial amputation or a hind- or midfoot amputation. Despite the theoretical benefits of hind- and midfoot-level amputation, we hypothesized that patients with transtibial amputations would report better function and have fewer complications. METHODS:The study included patients 18 to 60 years of age who were treated with a transtibial amputation (n = 77) or a distal amputation (n = 17) and who were enrolled in the prospective, multicenter Outcomes Following Severe Distal Tibial, Ankle, and/or Foot Trauma (OUTLET) study. The primary outcome was the difference in Short Musculoskeletal Function Assessment (SMFA) scores, and secondary outcomes included pain, complications, amputation revision, and amputation healing. RESULTS:There were no significant differences between patients with distal versus transtibial amputation in any of the domains of the SMFA: dysfunction index [distal versus transtibial], 31.2 versus 22.3 (p = 0.13); daily activities, 37.3 versus 26.0 (p = 0.17); emotional status, 41.4 versus 29.3 (p = 0.07); mobility, 36.5 versus 27.8 (p = 0.20); and bother index, 34.4 versus 23.6 (p = 0.14). Rates of complications requiring revision were higher for distal amputations but not significantly so (23.5% versus 13.3%; p = 0.28). One distal and no transtibial amputees required revision to a higher level (p = 0.18). A higher proportion of patients with distal compared with transtibial amputation required local surgical revision (17.7% versus 13.3%; p = 0.69). There was no significant difference between the distal and transtibial groups in scores on the Brief Pain Index at 18 months post-injury. CONCLUSIONS:Surgical complication rates did not differ significantly between patients who underwent transtibial versus hind- or midfoot amputation for severe lower-extremity injury. The average SMFA scores were higher (worse), although not significantly different, for patients undergoing distal compared with transtibial amputation, and more patients with distal amputation had a complication requiring surgical revision. Of note, more patients with distal amputation required closure with an atypical flap, which likely contributed to less favorable outcomes. LEVEL OF EVIDENCE:Therapeutic Level III . See Instructions for Authors for a complete description of levels of evidence.

Policy PointsTraditional approaches to addressing motor vehicle crashes are yielding diminishing returns. A comprehensive strategy known as the Safe Systems approach shows promise in both advancing safety and equity and reducing motor vehicle crashes.In addition, a range of emerging technologies, enabled by artificial intelligence, such as automated vehicles, impairment detection and telematics hold promise to advance road safety.Ultimately, the transportation system will need to evolve to provide the safe, efficient, and equitable movement of people and goods without reliance on private vehicle ownership, towards encouraging walking, bicycling and the use of public transportation.

Background: There are no standards for reliably measuring the quality of prosthetic fit and alignment which is important for evaluation and improvement of clinical care for patients with transtibial amputation. Objectives: The purpose of this study was to develop an instrument to quantitatively assess prosthetic fit and alignment in patients with transtibial amputation. Study Design: Prospective cohort study. Methods: The fit and alignment assessment (ProFit) included 39 items for assessments of skin quality, stance and gait, and radiographic characteristics that could be feasibly captured in clinic using photographs, video, and radiographs. Data were collected on adults aged 18-60 years treated with transtibial amputation and followed up for 18 months at 1 of 27 US hospitals. One hundred thirteen assessments were conducted by 6 prosthetists using an online platform. Items demonstrating reliability and face validity were included in the ProFit score for subsequent validation testing. Validation measures included 18-month patient-reported function (Short Musculoskeletal Function Assessment), tests of physical performance, patient-reported pain (Brief Pain Inventory), satisfaction with prosthesis (Orthotics Prosthetics Users Survey), prosthesis use, and walking activity. Results: The ProFit score included 10 of 39 items that demonstrated high inter-rater reliability and face validity. A higher ProFit score correlated with worse function on all domains of the Short Musculoskeletal Function Assessment except arm and hand and with worse performance on the 4-Square Step Test, Shuttle Run, and Illinois Agility Test. ProFit scores did not correlate with the Brief Pain Inventory, Orthotics Prosthetics Users Survey, prosthesis use, or walking activity. Conclusions: The ProFit score can be used by researchers and clinicians to measure the quality of socket fit and prosthetic alignment. Future prospective validation is necessary to verify the promising results observed in ProFit development and establish clinical utility.

(Abstracted from N Engl J Med 2022;387:385–388) This article presents the report of a blue-ribbon commission selected by the Commonwealth Fund. The first author of this report, Margaret Hamburg, is the chairman of the commission.

In current clinical practice, weight-bearing is typically restricted for up to 12 weeks after definitive fixation of lower extremity periarticular fractures. However, muscle atrophy resulting from restricting weight-bearing has a deleterious effect on bone healing and overall limb function. Antigravity treadmill therapy may improve recovery by allowing patients to safely load the limb during therapy, thereby reducing the negative consequences of prolonged non-weight-bearing while avoiding complications associated with premature return to full weight-bearing. This article describes a multicenter randomized controlled trial comparing outcomes after a 10-week antigravity treadmill therapy program versus standard of care in adult patients with periarticular fractures of the knee and distal tibia. The primary hypothesis is that, compared with patients receiving standard of care, patients receiving antigravity treadmill therapy will report better function 6 months after definitive treatment.

Summary: Limited data are available on the longer-term physical and psychosocial consequences after major extremity trauma apart from literature on the consequences after major limb amputation. The existing literature suggests that although variations in outcome exist, a significant proportion of service members and civilians sustaining major limb trauma will have less than optimal outcomes or health and rehabilitation needs over their life course. The proposed pilot study will address this gap in current research by locating and consenting METRC participants with the period of 5–7 years postinjury, identifying potential participation barriers and appropriate use of incentives, and conducting the follow-up examination at several data collection sites. The resulting data will inform the primary objective of refining and developing specific hypotheses to determine the design, scope, and feasibility of the main long-term consequences of major extremity trauma. Three METRC enrollment centers will contact past participants to achieve the goal of completing an interview, select patient-reported outcomes, perform a medical record review, and conduct an in-person clinic visit that will consist of a physical examination, blood draw, and x-ray of the study injury area. If successful, it will be possible to design studies to further examine these effects and develop future therapeutic interventions.

Background: Modern external ring fixation has been hypothesized to reduce complications requiring hospital readmission compared with internal fixation when treating patients with high-energy open tibial shaft fractures. In this study, the 1-year probability of a major limb complication was compared between external and internal fixation of severe open tibial fractures. Methods: This multicenter randomized clinical trial included patients 18 to 64 years of age with severe open tibial shaft fractures randomly assigned to either modern external ring fixation (n = 127) or internal fixation (n = 133). The primary outcome was a major limb complication within 365 days after randomization; these complications included amputation, infection, a soft-tissue problem, nonunion, malunion, and a loss of reduction/implant failure. Results: Of 260 randomized patients, 254 were included in the final analysis. Their mean age (standard deviation) was 39 (13) years; 214 (84%) were men. The probability of at least 1 major limb complication was higher for external fixation (62.1% [95% confidence interval (CI): 53.4% to 70.8%]) than internal fixation (43.7% [95% CI: 35.5% to 52.9%]), with a risk difference of 18.4% (95% CI: 5.8% to 30.4%); p = 0.005). The most notable difference was in loss of reduction/implant failure, the rate of which was higher for external fixation (risk difference: 14.4% [95% CI: 7.0% to 21.6%]; p = 0.002). There was no appreciable difference in the probability of deep infection between external fixation (26.1%) and internal fixation (29.7%) (risk difference: -3.5% [95% CI: -14.8% to 7.8%]; p = 0.54). There were also no appreciable differences in the probabilities of amputation, nonunion, soft-tissue problems, malunion, or fracture healing between the groups. Conclusions: These results argue against routine use of modern external ring fixation for the treatment of these severe open tibial fractures.

Background: Supplemental perioperative oxygen is a low-cost intervention theorized to reduce the risk of surgical site infections, but its effect among patients undergoing surgery for a tibial plateau, tibial pilon, or calcaneal fracture is unknown. We aimed to determine the effectiveness of a high fraction of inspired oxygen (FiO(2), 80%) versus low FiO(2) (30%) in reducing surgical site infections in these patients. Methods: A randomized controlled trial was conducted at 29 U.S. trauma centers. We enrolled 1,231 patients who were 18 to 80 years of age and had a tibial plateau, tibial pilon, or calcaneal fracture and were thought to be at elevated risk for infection based on their injury characteristics. Patients were randomized to receive 80% FiO(2) (treatment group) or 30% FiO(2) (control group) in the operating room and for up to 2 hours in the recovery room. The primary outcome was a composite of either deep surgical site infection (treated with surgery) or superficial surgical site infection (treated with antibiotics alone) within 182 days following definitive fixation. Secondary outcomes included these surgical site infections at 90 and 365 days after surgery. Results: The modified intention-to-treat analysis included 1,136 patients with 94% of expected follow-up through 182 days. Surgical site infection occurred in 40 (7.0%) of the patients in the treatment group and 60 (10.7%) of the patients in the control group (relative risk [RR], 0.65; 95% confidence interval [CI], 0.45 to 0.96; risk difference [RD], -3.8%; 95% CI, -7.2% to -0.4%; p = 0.03). The treatment intervention demonstrated a similar effect at 90 days (RR, 0.59; 95% CI, 0.37 to 0.93) and 365 days (RR, 0.62; 95% CI, 0.44 to 0.87). Secondary analyses demonstrated that the effect was driven by a reduction in superficial surgical site infections. Conclusions: Among tibial plateau, pilon, or calcaneal fracture patients at elevated risk for surgical site infection, a high perioperative FiO(2) lowered the risk of surgical site infection. The findings support the use of this intervention, although the benefit appears to mostly be in reduction of superficial infections.

Objectives: To compare outcomes in patients with open tibia shaft fractures based on defect size. Design: Retrospective review. Setting: Eighteen trauma centers. Population: The study included 132 patients with diaphyseal tibia bone defects >1 cm and ≥50% cortical loss treated with intramedullary nail. Outcomes: The primary outcome was number of secondary surgeries to promote healing (bone graft, revision fixation, or bone transport). Additional outcomes included occurrence of secondary surgeries (bone graft, infection, amputation, and flap failure) and proportion healed at one year. Results are compared by “radiographic apparent bone gap” of <2.5 or ≥2.5 cm. Results: The estimated conditional probability of bone grafting within one year given graft-free at 90 days was 44% and 47% in the <2.5 cm and ≥2.5 cm groups, respectively. An estimated infection risk of 14% was observed in both groups [adjusted hazard ratio (HR) 0.98, 95% confidence interval (CI): 0.33–2.92], estimated amputation risk was 9% (<2.5 cm) and 4% (≥2.5 cm) (unadjusted HR 0.66, 95% CI: 0.13–3.29), and estimated flap failure risk (among those with flaps) was 10% and 13%, respectively (unadjusted HR 1.71, 95% CI: 0.24–12.25). There was no appreciable difference in the proportion healed at one year between defect sizes [adjusted HR: 1.07 (95% CI, 0.63–1.82)]. Conclusions: Larger size bone defects were not associated with higher number of secondary procedures to promote healing or a lower overall one-year healing rate. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Objective: Time to care is a determinant of trauma patient outcomes, and timely delivery of trauma care to severely injured patients is critical in reducing mortality. Numerous studies have analyzed access to care using prehospital intervals from a Carr et al. meta-analysis of studies from 1975 to 2005. Carr et al.'s research sought to determine national mean activation and on-scene intervals for trauma patients using contemporary emergency medical services (EMS) records. Since the Carr et al. meta-analysis was published, the National Highway Traffic Safety Administration (NHTSA) created and refined the National Emergency Medical Services Information System (NEMSIS) database. We sought to perform a modern analysis of prehospital intervals to establish current standards and temporal patterns.Methods: We utilized NEMSIS to analyze EMS data of trauma patients from 2016 to 2019. The dataset comprises more than 94 million EMS records, which we filtered to select for severe trauma and stratified by type of transport and rurality to calculate mean activation and on-scene intervals. Furthermore, we explored the impact of basic life support (BLS) and advanced life support (ALS) of ground units on activation and on-scene time intervals.Results: Mean activation and on-scene intervals for ground transport were statistically different when stratified by rurality. Urban, suburban, and rural ground activation intervals were 2.60 ± 3.94, 2.88 ± 3.89, and 3.33 ± 4.58 minutes, respectively. On-scene intervals were 15.50 ± 10.46, 17.56 ± 11.27, and 18.07 ± 16.13 minutes, respectively. Mean helicopter transport activation time was 13.75 ± 7.44 minutes and on-scene time was 19.42 ± 16.09 minutes. This analysis provides an empirically defined mean for activation and on-scene times for trauma patients based on transport type and rurality. Results from this analysis proved to be significantly longer than the previous analysis, except for helicopter transport on-scene time. Shorter mean intervals were seen in ALS compared to BLS for activation intervals, however ALS on-scene intervals were marginally longer than BLS.Conclusions: With the increasing sophistication of geospatial technologies employed to analyze access to care, these intervals are the most accurate and up-to-date and should be included in access to care models.

Background: Studies have suggested that patient-centered collaborative care in the early phases of recovery may assist providers and patients in managing the multifactorial consequences of injury and may lead to better outcomes. This cluster-controlled trial, conducted at 12 U.S. Level-I trauma centers, was designed to evaluate the impact of the Trauma Collaborative Care (TCC) program on 1-year outcomes following severe musculoskeletal injury. Methods: Patients with high-energy orthopaedic trauma requiring surgical fixation were prospectively enrolled. Six sites implemented the TCC intervention as well as the Trauma Survivors Network (TSN), and the other 6 sites provided the standard of care. Participants were followed for 1 year, and a composite primary outcome measure composed of the Short Musculoskeletal Function Assessment (SMFA) Dysfunction Index, Patient Health Questionnaire-9 (PHQ-9), and Posttraumatic Stress Disorder Checklist (PCL) was assessed. A 2-stage, Bayesian hierarchical statistical procedure was used to characterize treatment effects. Sensitivity analyses were conducted to account for an error in the delivery of the intervention. Results: There were 378 patients enrolled at 6 trauma centers implementing the TCC program, and 344 patients enrolled at 6 trauma centers providing usual care. Patient utilization of treatment components varied across the intervention sites: 29% of patients in the intervention group received all 5 key components (TSN handbook education, peer visits, recovery assessment, and calls before and after recovery assessment). Posterior estimates of the intention-to-treat effect suggested that the intervention did not have an appreciable effect: the odds of the composite outcome for the TCC group increased by 5% (95% credible interval, -40% to 63%). The estimates of the effect of receiving all 5 key intervention components were similar. Conclusions: Despite prior work showing early positive effects, this analysis suggests that the TCC program as delivered did not have positive effects on patient outcomes at 1 year. It is not known whether programs that improve compliance or target specific subgroups would better meet the psychosocial needs of trauma survivors.

Background: Severe lower extremity trauma among working-age adults is highly consequential for returning to work; however, the economic impact attributed to injury has not been fully quantified. The purpose of this study was to examine work and productivity loss during the year following lower extremity trauma and to calculate the economic losses associated with lost employment, lost work time (absenteeism), and productivity loss while at work (presenteeism). Methods: This is an analysis of data collected prospectively across 3 multicenter studies of lower extremity trauma outcomes in the United States. Data were used to construct a Markov model that accumulated hours lost over time due to lost employment, absenteeism, and presenteeism among patients from 18 to 64 years old who were working prior to their injury. Average U.S. wages were used to calculate economic loss overall and by sociodemographic and injury subgroups. Results: Of 857 patients working prior to injury, 47.2% had returned to work at 1 year. The average number of productive hours of work lost was 1,758.8/person, representing 84.6% of expected annual productive hours. Of the hours lost, 1,542.3 (87.7%) were due to working no hours or lost employment, 71.1 (4.0%) were due to missed hours after having returned, and 145.4 (8.3%) were due to decreased productivity while working. The 1-year economic loss due to injury totaled $64,427/patient (95% confidence interval [CI], $63,183 to $65,680). Of the 1,758.8 lost hours, approximately 88% were due to not being employed (working zero hours), 4% were due to absenteeism, and 8% were due to presenteeism. Total productivity loss was higher among older adults (≥40 years), men, those with a physically demanding job, and the most severe injuries (i.e., those leading to amputation as well as Gustilo type-IIIB tibial fractures and type-III pilon/ankle fractures). Conclusions: Patients with severe lower extremity trauma carry a substantial economic burden. The costs of lost productivity should be considered when evaluating outcomes.

Objectives: Assess the burden and co-occurrence of pain, depression, and posttraumatic stress disorder (PTSD) among service members who sustained a major limb injury, and examine whether these conditions are associated with functional outcomes. Design: A retrospective cohort study. Setting: Four U.S. military treatment facilities: Walter Reed Army Medical Center, National Naval Medical Center, Brooke Army Medical Center, and Naval Medical Center San Diego. Patients/Participants: Four hundred twenty-nine United States service members who sustained a major limb injury while serving in Afghanistan or Iraq met eligibility criteria upon review of their medical records. Intervention: Not applicable. Main Outcome Measurements: Outcomes assessed were: function using the short musculoskeletal functional assessment; PTSD using the PTSD Checklist and diagnostic and statistical manual criteria; pain using the chronic pain grade scale. Results: Military extremity trauma and amputation/limb salvage patients without pain, depression, or PTSD, were, on average, about one minimally clinically important difference (MCID) from age- and gender-adjusted population norms. In contrast, patients with low levels of pain and no depression or PTSD were, on average, one to 2 MCIDs from population norms. Military extremity trauma and amputation/limb salvage patients with either greater levels of pain, and who experience PTSD, depression, or both, were 4 to 6 MCIDs from population norms. Regression analyses adjusting for injury type (upper or lower limb, salvage or amputation, and unilateral or bilateral), age, time to interview, military rank, presence of a major upper limb injury, social support, presence of mild traumatic brain injury/concussion, and combat experiences showed that higher levels of pain, depression, and PTSD were associated with lower one-year functional outcomes. Conclusions: Major limb trauma sustained in the military results in significant long-term pain and PTSD. Overall, the results are consistent with the hypothesis that pain, depression, and PTSD are associated with disability in this population. Level of Evidence: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Background: Selecting the best treatment for patients with severe terminal lower-limb injury remains a challenge. For some injuries, amputation may result in better outcomes than limb salvage. This study compared the outcomes of patients who underwent limb salvage with those that would have been achieved had they undergone amputation. Methods: This multicenter prospective observational study included patients 18 to 60 years of age in whom a Type-III pilon or IIIB or C ankle fracture, a Type-III talar or calcaneal fracture, or an open or closed blast/crush foot injury had been treated with limb salvage (n = 488) or amputation (n = 151) and followed for 18 months. The primary outcome was the Short Musculoskeletal Function Assessment (SMFA). Causal effect estimates of the improvement that amputation would have provided if it had been performed instead of limb salvage were calculated for the SMFA score, physical performance, pain, participation in vigorous activities, and return to work. Results: The patients who underwent limb salvage would have had small differences in most outcomes had they undergone amputation. The most notable difference was an improvement in the SMFA mobility score of 7 points (95% confidence interval [CI] = 2.0 to 10.7). Improvements were largest for pilon/ankle fractures and complex injury patterns. Conclusions: Amputation should be considered a treatment option rather than a last resort for the most complex terminal lower-limb injuries.

Objective To examine the effect of severe lower extremity trauma on meeting Physical Activity Guidelines for Americans (PAGA) 18 months after injury and perform an exploratory analysis to identify demographic, clinical, and psychosocial factors associated with meeting PAGA. Design Secondary analysis of observational cohort study. Setting A total of 34 United States trauma centers Participants A total of 328 adults with severe distal tibia, ankle and mid- to hindfoot injuries treated with limb reconstruction (N=328). Interventions None. Main Outcome Measures The Paffenbarger Physical Activity Questionnaire was used to assess physical activity levels 18 months after injury. Meeting PAGA was defined as combined moderate- and vigorous-intensity activity ≥150 minutes per week or vigorous-intensity activity ≥75 minutes per week. Results Fewer patients engaged in moderate- or vigorous-intensity activity after injury compared with before injury (moderate: 44% vs 66%, P<.001; vigorous: 18% vs 29%; P<.001). Patients spent 404±565 minutes per week in combined moderate- to vigorous-intensity activity before injury compared with 224±453 minutes postinjury (difference: 180min per week; 95% confidence interval [CI], 103-256). The adjusted odds of meeting PAGA were lower for patients with depression (adjusted odds ratio [AOR], 0.45; 95% CI, 0.28-0.73), women (AOR, 0.59; 95% CI, 0.35-1.00), and Black or Hispanic patients (AOR, 0.49; 95% CI, 0.28-0.85). Patients meeting PAGA prior to injury were more likely to meet PAGA after injury (odds ratio, 2.0; 95% CI, 1.20-3.31). Conclusions Patients spend significantly less time in moderate- to vigorous-intensity physical activity after injury. Patients with depression are less likely to meet PAGA. Although the causal relationship is unclear, results highlight the importance of screening for depression.

OBJECTIVE:To evaluate the diagnostic performance of perfusion pressure (PP) thresholds for fasciotomy.DESIGN:Prospective observational study.SETTING:Seven Level-1 trauma centers.PATIENTS/PARTICIPANTS:One hundred fifty adults with severe leg injuries and ≥2 hours of continuous PP data who had been enrolled in a multicenter observational trial designed to develop a clinical prediction rule for acute compartment syndrome (ACS).MAIN OUTCOME MEASUREMENTS:For each patient, a given PP criterion was positive if it was below the specified threshold for at least 2 consecutive hours. The diagnostic performance of PP thresholds between 10 and 30 mm Hg was determined using 2 reference standards for comparison: (1) the likelihood of ACS as determined by an expert panel who reviewed each patient's data portfolio or (2) whether the patient underwent fasciotomy.RESULTS:Using the likelihood of ACS as the diagnostic standard (ACS considered present if median likelihood ≥70%, absent if <30%), a PP threshold of 30 mm Hg had diagnostic sensitivity 0.83, specificity 0.53, positive predictive value 0.07, and negative predictive value 0.99. Results were insensitive to more strict likelihood categorizations and were similar for other PP thresholds between 10- and 25-mm Hg. Using fasciotomy as the reference standard, the same PP threshold had diagnostic sensitivity 0.50, specificity 0.50, positive predictive value 0.04, negative predictive value 0.96.CONCLUSION:No value of PP from 10 to 30 mm Hg had acceptable diagnostic performance, regardless of which reference diagnostic standard was used. These data question current practice of diagnosing ACS based on PP and suggest the need for further research.LEVEL OF EVIDENCE:Diagnostic Level I. See Instructions for Authors for a complete description of levels of evidence.

The detailed study of prehospital injury death is critical to advancing trauma and emergency care, as circumstance and causality have significant implications for the development of mitigation strategies. Though there is no true 'Golden Hour,' the time from injury to care is a critical element in the analysis matrix, particularly in patients with severe injury. Currently, there is no standard method for the assessment of time to definitive care after injury among prehospital deaths. This article describes a methodology to estimate total prehospital time and distance for trauma patients transported via ground emergency medical services and helicopter emergency medical services using a geographic information system. Data generated using this method, along with medical examiner and field investigation reports, will be used to estimate the potential survivability of prehospital trauma deaths occurring in five US states and the District of Columbia as part of the Multi-Institutional Multidisciplinary Injury Mortality Investigation in the Civilian Pre-Hospital Environment study. One goal of this work is to develop standard metrics for the assessment of total prehospital time and distance, which can be used in the future for more complex spatial analyses to gain a deeper understanding of trauma center access. Results will be used to identify high priority areas for research and development in injury prevention, trauma system performance improvement, and public health.