Blast-induced lower extremity fractures with arterial injury: prevalence and risk factors for amputation after initial limb-preserving treatment

Upper-Extremity Vascular Exposures for Trauma: Comparative Performance Outcomes for General Surgeons and Orthopedic Surgeons

INTRODUCTION

As combat-related trauma decreases, there remains an increasing need to maintain the ability to care for trauma victims from other casualty events around the world (e.g., terrorism, natural disasters, and infrastructure failures). During these events, military surgeons often work closely with their civilian counterparts, often in austere and expeditionary contexts. In these environments, the primary aim of the surgical team is to implement damage control principles to avert blood loss, optimize oxygenation, and improve survival. Upper-extremity vascular injuries are associated with high rates of morbidity and mortality resulting from exsanguination and ischemic complications; however, fatalities may be avoided if hemorrhage is rapidly controlled. In austere contexts, deployed surgical teams typically include one general surgeon and one orthopedic surgeon, neither of which have acquired the expertise to manage these vascular injuries. The purpose of this study was to examine the baseline capabilities of general surgeons and orthopedic surgeons to surgically expose and control axillary and brachial arteries and to determine if the abilities of both groups could be increased through a focused cadaver-based training intervention.

METHODS

This study received IRB approval at our institution. Study methods included the use of cadavers for baseline assessment of procedural capabilities to expose and control axillary and brachial vessels, followed by 1:1 procedural training and posttraining re-assessment of procedural capabilities. Inferential analyses included ANOVA/MANOVA for within- and between-group effects (P < .05). Effect sizes were calculated using Cohen's d.

RESULTS

Study outcomes demonstrated significant differences between the baseline performance abilities of the two groups, with general surgeons outperforming orthopedic surgeons. Before training, neither group reached performance benchmarks for overall or critical procedural abilities in exposing axillary and brachial vessels. Training led to increased abilities for both groups. There were statistically significant gains for overall procedural abilities, as well as for critical procedural elements that are directly associated with morbidity and mortality. These outcomes were consistent for both general and orthopedic surgeons. Effect sizes ranged between medium (general surgeons) and very large (orthopedic surgeons).

CONCLUSION

There was a baseline capability gap for both general surgeons and orthopedic surgeons to surgically expose and control the axillary and brachial vessels. Outcomes from the course suggest that the methodology facilitates the acquisition of accurate and independent vascular procedural capabilities in the management of upper-extremity trauma injuries. The impact of this training for surgeons situated in expeditionary or remote contexts has direct relevance for caring for victims of extremity trauma. These outcomes underscore the need to train all surgeons serving in rural, remote, expeditionary, combat, or global health contexts to be able to competently manage extremity trauma and concurrent vascular injuries to increase the quality of care in those settings.

American Association for the Surgery of Trauma-World Society of Emergency Surgery guidelines on diagnosis and management of peripheral vascular injuries

The peripheral arteries and veins of the extremities are among the most commonly injured vessels in both civilian and military vascular trauma. Blunt causes are more frequent than penetrating except during military conflicts and in certain geographic areas. Physical examination and simple bedside investigations of pulse pressures are key in early identification of these injuries. In stable patients with equivocal physical examinations, computed tomography angiograms have become the mainstay of screening and diagnosis. Immediate open surgical repair remains the first-line therapy in most patients. However, advances in endovascular therapies and more widespread availability of this technology have resulted in an increase in the range of injuries and frequency of utilization of minimally invasive treatments for vascular injuries in stable patients. Prevention of and early detection and treatment of compartment syndrome remain essential in the recovery of patients with significant peripheral vascular injuries. The decision to perform amputation in patients with mangled extremities remains difficult with few clear indicators. The American Association for the Surgery of Trauma in conjunction with the World Society of Emergency Surgery seeks to summarize the literature to date and provide guidelines on the presentation, diagnosis, and treatment of peripheral vascular injuries. LEVEL OF EVIDENCE: Review study, level IV.

Utility of the Mangled Extremity Severity Score in Predicting Amputation in Military Lower Extremity Arterial Injury

BACKGROUND

Effective amputation prediction may help inform appropriate early limb salvage efforts in military lower extremity (LE) arterial injury. The Mangled Extremity Severity Score (MESS) is the most commonly applied system for early amputation prediction but its utility in military trauma is unknown.

METHODS

Retrospective cohort study of Iraq and Afghanistan casualties with LE arterial injury who underwent a vascular limb salvage attempt. Retrospectively assessed MESS was statistically explored as an amputation predictor and MESS component surrogates (mechanism, vascular injury characteristics, tourniquet use, and transfusion volume) were used to characterize limb injuries by presenting characteristics and evaluated for amputation prediction.

RESULTS

A total of 439 limbs were included with 99 (23%) amputations, 29 (7%) within 48 hr of injury. Median MESS was 5 (interquartile range 4-6) among salvaged limbs and 7 (5-9) among amputations (P < 0.0001). An MESS cutoff of ≥7 had a better receiver operating characteristic sensitivity/specificity profile (area under the curve 0.696 overall, 0.765 amputation within 48 hr) than MESS ≥8 (0.593, 0.621), but amputation rates were only 43% for MESS ≥7 and 50% for ≥8. MESS ≥7 was significantly associated with age, polytrauma, blast or crush mechanism, fracture, tourniquet use, distal (popliteal/tibial) and multiple arterial injuries, and massive transfusion. Amputation was significantly associated with polytrauma, blast or crush mechanism, fracture, and massive transfusion; however, 83 casualties had all 4 characteristics with an amputation rate of only 46%.

CONCLUSIONS

In combat casualties with arterial injury, LE amputation after attempted vascular limb salvage is inadequately predicted by existing scoring systems or the presenting characteristics available in this registry. Limb loss is predominantly late and likely because of factors not projectable at initial presentation.

Predictors and timing of amputations in military lower extremity trauma with arterial injury

INTRODUCTION

Military lower extremity arterial injuries present threats to life and limb. These injuries are common and limb salvage is a trauma system priority. Understanding the timing and predictors of amputation through the phases of casualty evacuation can help inform future limb salvage efforts. This study characterizes limbs undergoing amputation at different operationally relevant time points.

METHODS

A retrospective cohort study of casualties with lower extremity arterial injuries undergoing initial vascular limb salvage in Iraq and Afghanistan was undertaken. Amputations were grouped as having been performed early (in theater at Role 2 or 3) or late (after evacuation to Role 4 or 5). Further distinction was made between late and delayed (after discharge from initial hospitalization) amputations.

RESULTS

Four hundred fifty-five casualties met inclusion criteria with 103 amputations (23%). Twenty-one (20%) were performed in theater and 82 (80%) were performed following overseas evacuation. Twenty-one (26% of late amputations) were delayed, a median of 359 days from injury (interquartile range, 176-582). Most amputations were performed in the first 4 days following injury. Amputation incidence was highest in popliteal injuries (28%). Overall, amputation was predicted by higher incidence of blast mechanism and fracture and greater limb and casualty injury severity. Early amputations had higher limb injury severity than late amputations. Delayed amputations had greater incidence of motor and sensory loss and contracture than early amputations.

CONCLUSION

Casualty and limb injury severity predict predictors and timing of amputation in military lower extremity arterial injury. Amputation following overseas evacuation was more common than in-theater amputation, and functional loss is associated with delayed amputation. Future limb salvage efforts should focus on postevacuation and rehabilitative care.

LEVEL OF EVIDENCE

Epidemiologic study, level III.

High-Level Performance After the Return to Run Clinical Pathway in Patients Using the Intrepid Dynamic Exoskeletal Orthosis

BACKGROUND

Severe ankle and foot injuries in the US military can result in high-level functional limitation, lost duty days, and medical discharge.

OBJECTIVE

To assess the effectiveness of the Return to Run Clinical Pathway (RTR) in returning patients with lower extremity fractures who utilized the Intrepid Dynamic Exoskeletal Orthosis (IDEO) to high-level mobility.

METHODS

Thirty servicemembers with lower extremity fractures who utilized the IDEO unilaterally and completed the RTR at Naval Medical Center San Diego were included in this retrospective operational review. The Comprehensive High-level Activity Mobility Predictor (CHAMP) and all subtests were completed prior to and after completion of the RTR as part of routine clinical care. An analysis of covariance (ANCOVA) was used to compare CHAMP scores before and after the RTR.

RESULTS

Significant improvements were found in the T test (mean change, faster by 5.3 seconds; 95% confidence interval: 3.6, 7.1 seconds; P = .03) and total CHAMP score (mean change, 4.2 points; 95% confidence interval: 3.0, 5.3 points; P<.05). No significant changes were noted in the single-legged stance subtest, the Edgren sidestep test, or the Illinois agility test.

CONCLUSION

The RTR led to improvements in high-level, multidirectional mobility in IDEO users with a history of fractures. Applicability of the intervention used in this study requires further validation before widespread use.

LEVEL OF EVIDENCE

Therapy, level 4. J Orthop Sports Phys Ther 2019;49(7):529-535. Epub 13 Feb 2019. doi:10.2519/jospt.2019.8763.

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 of Soft Tissue Reconstruction for Traumatic Lower Extremity Fractures with Compromised Vascularity

Traumatic lower extremity fractures with compromised arterial flow are limb-threatening injuries. A retrospective review of 158 lower extremities with traumatic fractures, including 26 extremities with arterial injuries, was performed to determine the effects of vascular compromise on flap survival, successful limb salvage and complication rates. Patients with arterial injuries had a larger average flap surface area (255.1 vs 144.6 cm2, P = 0.02) and a greater number of operations (4.7 vs 3.8, P = 0.01) than patients without vascular compromise. Patients presenting with vascular injury were also more likely to require fasciotomy [odds ratio (OR): 6.5, confidence interval (CI): 2.3–18.2] and to have a nerve deficit (OR: 16.6, CI: 3.9–70.0), fracture of the distal third of the leg (OR: 2.9, CI: 1.15–7.1) and intracranial hemorrhage (OR: 3.84, CI: 1.1–12.9). After soft tissue reconstruction, patients with arterial injuries had a higher rate of amputation (OR: 8.5, CI: 1.3–53.6) and flap failure requiring a return to the operating room (OR: 4.5, CI: 1.5–13.2). Arterial injury did not correlate with infection or overall complication rate. In conclusion, arterial injuries resulted in significant complications for patients with lower extremity fractures requiring flap coverage, although limb salvage was still effective in most cases.

Do inflammatory markers portend heterotopic ossification and wound failure in combat wounds?

BACKGROUND

After a decade of war in Iraq and Afghanistan, we have observed an increase in combat-related injury survival and a paradoxical increase in injury severity, mainly because of the effects of blasts. These severe injuries have a devastating effect on each patient's immune system resulting in massive upregulation of the systemic inflammatory response. By examining inflammatory mediators, preliminary data suggest that it may be possible to correlate complications such as wound failure and heterotopic ossification (HO) with distinct systemic and local inflammatory profiles, but this is a relatively new topic.

QUESTIONS/PURPOSES

We asked whether systemic or local markers of inflammation could be used as an objective means, independent of demographic and subjective factors, to estimate the likelihood of (1) HO and/or (2) wound failure (defined as wounds requiring surgical débridement after definitive closure, or wounds that were not closed or covered within 21 days of injury) in patients sustaining combat wounds.

METHODS

Two hundred combat wounded active-duty service members who sustained high-energy extremity injuries were prospectively enrolled between 2008 and 2012. Of these 200 patients, 189 had adequate followups to determine the presence or absence of HO, and 191 had adequate followups to determine the presence or absence of wound failure. In addition to injury-specific and demographic data, we quantified 24 cytokines and chemokines during each débridement. Patients were followed clinically for 6 weeks, and radiographs were obtained 3 months after definitive wound closure. Associations were investigated between these markers and wound failure or HO, while controlling for known confounders.

RESULTS

The presence of an amputation (p < 0.001; odds ratio [OR], 6.1; 95% CI. 1.63-27.2), Injury Severity Score (p = 0.002; OR, 33.2; 95% CI, 4.2-413), wound surface area (p = 0.001; OR, 1.01; 95% CI, 1.002-1.009), serum interleukin (IL)-3 (p = 0.002; OR, 2.41; 95% CI, 1.5-4.5), serum IL-12p70 (p = 0.01; OR, 0.49; 95% CI, 0.27-0.81), effluent IL-3 (p = 0.02; OR, 1.75; 95% CI, 1.2-2.9), and effluent IL-13 (p = 0.006; OR, 0.67; 95% CI, 0.50-0.87) were independently associated with HO formation. Injury Severity Score (p = 0.05; OR, 18; 95% CI, 5.1-87), wound surface area (p = 0.05; OR, 28.7; 95% CI, 1.5-1250), serum procalcitonin ([ProCT] (p = 0.03; OR, 1596; 95% CI, 5.1-1,758,613) and effluent IL-6 (p = 0.02; OR, 83; 95% CI, 2.5-5820) were independently associated with wound failure.

CONCLUSIONS

We identified associations between patients' systemic and local inflammatory responses and wound-specific complications such as HO and wound failure. However, future efforts to model these data must account for their complex, time dependent, and nonlinear nature.

LEVEL OF EVIDENCE

Level II, prognostic study. See the Instructions for Authors for a complete description of levels of evidence.