Ultrasound Imaging in Diagnosis and Management of Lower Limb Injuries: A Comprehensive Review.

Medical imaging tests are widely used to diagnose a broad spectrum of lower-limb injuries. Among these modalities, ultrasound (US) imaging has gained significant traction as a valuable diagnostic instrument for assessing conditions primarily affecting muscles, tendons, ligaments, and other soft tissues. However, there are important dilemmas related to the indications and possibilities of US in lower-limb injuries. Conflicting findings and approaches raise questions regarding the validity, accuracy, and usefulness of the US in that area. This narrative review attempts to summarize the current state of knowledge regarding US imaging of lower-limb injuries. The study provides a detailed discussion of the existing literature and contemporary insights on the diagnosis of lower-limb injuries using US examination, and draws attention to the role of the US in interventional procedures and monitoring of the healing process. The characteristics of normal muscles, tendons, and ligaments in US imaging are presented, along with the most commonly documented conditions affecting these tissues. Furthermore, the benefits and justifications for employing US in interventional procedures are discussed, ranging from platelet-rich plasma injections to physiotherapeutic treatments like percutaneous electrolysis. The study was further augmented with US pictures depicting various lower-limb injuries, mainly affecting young athletes. This article aims to review the role of US imaging in the diagnosis and management of common lower-limb injuries.

Cost-effectiveness analysis of routine computed tomography angiography (CTA) for lower extremity penetrating trauma.

BACKGROUND: Routine evaluation with CTA for patients with isolated lower extremity penetrating trauma and normal ankle-brachial-indices (ABI) remains controversial. While prior literature has found normal ABI's (≥0.9) and a normal clinical examination to be adequate for safe discharge, there remains concern for missed injuries which could lead to delayed surgical intervention and unnecessary morbidity. Our hypothesis was that routine CTA after isolated lower extremity penetrating trauma with normal ABIs and clinical examination is not cost-effective. METHODS: We performed a decision-analytic model to evaluate the cost-effectiveness of obtaining a CTA routinely compared to clinical observation and ABI evaluation in hemodynamically normal patients with isolated penetrating lower extremity trauma. Our base case was a patient that sustained penetrating lower extremity trauma with normal ABIs that received a CTA in the trauma bay. Costs, probability, and Quality-Adjusted Life Years (QALYs) were generated from published literature. RESULTS: Clinical evaluation only (no CTA) was cost-effective with a cost of $2056.13 and 0.98 QALYs gained compared to routine CTA which had increased costs of $7449.91 and lower QALYs 0.92. Using one-way sensitivity analysis, routine CTA does not become the cost-effective strategy until the cost of a missed injury reaches $210,075.83. CONCLUSIONS: Patients with isolated, penetrating lower extremity trauma with normal ABIs and clinical examination do not warrant routine CTA as there is no benefit with increased costs.

Clinical validation of the "Straight-Leg-Evaluation-Trauma-Test" (SILENT) as a rapid assessment tool for injuries of the lower extremity in trauma bay patients.

PURPOSE: Clinical assessment of the major trauma patient follows international validated guidelines without standardized trauma-specific assessment of the lower extremities for injuries. This study aimed to validate a novel clinical test for lower extremity evaluation during trauma resuscitation phase. METHODS: This diagnostic, prognostic observational cohort study was performed on trauma patient treated at one level I trauma center between Mar 2022 and Mar 2023. The Straight-Leg-Evaluation-Trauma (SILENT) test follows three steps during the primary survey: inspection for obvious fractures (e.g., open fracture), active elevation of the leg, and cautious elevation of the lower extremity from the heel. SILENT was considered positive when obvious fracture was present and painful or pathological mobility was observed. The SILENT test was compared with standardized radiographs (CT scan or X-ray) as the reference test for fractures. Statistical analysis included sensitivity, specificity, and receiver operating characteristic testing. RESULTS: 403 trauma bay patients were included, mean age 51.6 (SD 21.2) years with 83 fractures of the lower extremity and 27 pelvic/acetabular fractures. Overall sensitivity was 75% (95%CI 64 to 84%), and overall specificity was 99% (95%CI 97 to 100%). Highest sensitivity was for detection of tibia fractures (93%, 95%CI 77 to 99%). Sensitivity of SILENT was higher in the unconscious patient (96%, 95%CI 78 to 100%) with a near 100% specificity. AUC was highest for tibia fractures (0.96, 95%CI 0.92 to 1.0) followed by femur fractures (0.92, 95%CI 0.84 to 0.99). CONCLUSION: The SILENT test is a clinical applicable and feasible rule-out test for relevant injuries of the lower extremity. A negative SILENT test of the femur or the tibia might reduce the requirement of additional radiological imaging. Further large-scale prospective studies might be required to corroborate the beneficial effects of the SILENT test.

Microvascular reconstruction for complex lower-extremity trauma in pregnancy.

Microvascular reconstruction in pregnancy is rare. We report a case of complex distal lower-extremity trauma in early pregnancy reconstructed with a microvascular free muscle flap. A 30-year-old female with 13 weeks gestation had a crush avulsion of the distal left leg with medial malleolar fracture; she had two sessions of debridement, joint stabilising external fixator frame, and a vaccum assisted closure dressing application. Two weeks later, a right latissimus muscle flap was harvested. Flap was transferred to the debrided leg defect. The thoracodorsal vessels were anastomosed end to end to the anterior tibial artery and the concomitant vein. The flap was immediately revascularised. Continuous post-operative heparin infusion was administered. The muscle was covered with split-thickness skin graft 48 hrs later. Healing and post-operative recovery were uneventful. This report suggests that careful surgical and anesthetic techniques, along with a balanced post-operative anticoagulation protocol, can achieve satisfactory microvascular reconstruction in pregnancy.

Lower Extremity Sandblast Injury: A Rarely Seen Injury Mechanism in the Civilian Population.

Blast injuries are both complex and rare in the civilian population. This combination can often lead to missed opportunities for early, effective intervention. This is a case report of a 31-year-old male who suffered a lower extremity blast injury while using an industrial sandblaster. This blast injury presented as a closed degloving, or Morel-Lavallee lesion, which can easily be mistreated and lead to infection and further disability. Following assessment, identification, and confirmation of the Morel-Lavallee lesion via radiographic imaging, this patient underwent debridement surgery, wound vac therapy, and antibiotic treatment before being discharged home with no major physiologic or neurologic deficits. The purpose of this report is to highlight the importance of assessing for closed degloving injuries when presented with blast injury traumas in the civilian trauma setting, and outlines the process utilized for assessment and treatment.

Location of Hamstring Injuries Based on Magnetic Resonance Imaging: A Systematic Review.

CONTEXT: Hamstring muscle injury location using magnetic resonance imaging (MRI) is not so well described in the literature. OBJECTIVE: To describe the location of hamstring injuries using MRI. DATA SOURCES: PubMed, Web of Science, Scopus, SPORTDiscus, Cochrane Library. STUDY SELECTION: The full text of studies, in English, had to be available. Case reports and reviews were excluded. Included studies must report the location of hamstring injuries using MRI within 8 days of the acute injury. STUDY DESIGN: Systematic review. LEVEL OF EVIDENCE: Level 4. DATA EXTRACTION: A first screening was conducted based on title and abstract of the articles. In the second screening, the full text of the remaining articles was evaluated for the fulfillment of the inclusion criteria. RESULTS: From the 2788 references initially found in 5 databases, we included 34 studies, reporting a total of 2761 acute hamstring injuries. The most frequent muscle head involved was the long head of the biceps femoris (BFLH) (70%), followed by the semitendinosus (ST) (15%), generally associated with BFLH. The most frequent tissue affected was the myotendinous junction (MTJ) accounting for half the cases (52%). Among all lesions, the distribution between proximal, central, and distal lesions looked homogenous, with 34.0%, 33.4% and 32.6%, respectively. The stretching mechanism, while only reported in 2 articles, represented 3% of all reported mechanisms, appears responsible for a specific lesion involving the proximal tendon of the semimembranosus (SM), and leading to a longer time out from sport. CONCLUSION: BFLH was the most often affected hamstring injuries and MTJ was the most affected tissue. In addition, the distal, central, and proximal locations were homogeneously distributed. We also noted that MRI descriptions of hamstring injuries are often poor and did not take full advantage of the MRI strengths. SYSTEMATIC REVIEW REGISTRATION: Before study initiation, the study was registered in the PROSPERO International prospective register of systematic reviews (registration number CRD42018107580).

An assessment of the diagnosis, treatment, and outcomes of lower extremity stress fractures in pediatric and adolescent populations.

OBJECTIVES: To present one of the first descriptive case series of pediatric and adolescent lower extremity stress injuries, their management, and outcomes in athletes and non-athletes. METHODS: The IRB-approved retrospective study included patients under 18 years at a tertiary children's hospital who were diagnosed with a lower extremity stress fracture/reaction. Demographic data, mechanism of injury, physical exam, radiographic findings, treatment, & outcomes were collected. Descriptive statistical analysis was conducted. RESULTS: Ninety-seven patients with stress injuries on clinical exams and on radiographs or MRI were included. The average age when diagnosed was 11.7 years (range 1.1-18 years) and the most common injuries were to the tibia (n = 33, 28.4%) and the least common involved were the cuneiforms (n = 4, 3.4%). Patients under the age of 14 were more likely to experience cuboid and calcaneal stress injuries (mean age 5.5 and 8.3 years respectively). Nineteen patients (19.6%) had high-risk stress fractures, with the average age of 14.9 years versus 11.6 for those with low risk (p-value = 0.01) and return to activity time being 15 weeks compared to 10.5 (p-value = 0.027). The most common forms of treatment were controlled ankle motion (CAM), walker boots (58.6%), and physical therapy (PT) (38.1%). The mean Lower Extremity Function Score of the patient population was 73.8, indicating no clinically important difference from full functionality. CONCLUSION: Lower extremity stress injuries in this cohort were most seen in the tibia, although patients younger than 14 had a high number of cuboid and calcaneal stress injuries. Those with high-risk stress fractures were older and took longer to recover from when compared to low-risk injuries. Treatment is commonly conservative, with CAM boots and PT being the most frequently utilized interventions and serving as a successful approach to treatment, with patients returning to activity at an average of 11.4 weeks, which is comparable to similar studies.

MRI classification of calf injuries - a reliability study and correlation with return to play in professional rugby players.

OBJECTIVE: To assess the validity and reliability of the calf injury classification system proposed by the Olympic Park group which focuses on connective tissue structure integrity on MRI. MATERIALS AND METHODS: A retrospective study analysing calf muscle group injuries in an English Premiership professional rugby union club using the MRI classification proposed by the Olympic Park group. Classification on MRI examinations of 28 calf injuries sustained over a 6-year period was performed by three independent musculoskeletal radiologists to determine the inter-observer variability and correlation of the grade of injury with return-to-full-training (RTFT) time. RESULTS: RTFT time ranged from 5 to 110 days (mean = 40.1, SD = 26.4) following calf muscle injury. The Olympic Park classification injury grade demonstrated moderate to strong correlation with RTFT time (Spearman's rank correlation coefficient, 0.661-0.715, p < 0.01). RTFT time was statistically different between different injury grades (one-way ANOVA, p < 0.01). Inter-observer agreement of the overall grade between radiologist pairs was fair to moderate (weighted kappa 0.406-0.583). CONCLUSION: The Olympic Park classification system demonstrates moderate to strong correlation with time to RTFT following calf injury. Inter-observer reliability is fair to moderate.

Dual energy CT angiography for lower extremity trauma: comparison with conventional CT.

PURPOSE: To determine if rapid switching dual-energy CT (rsDECT) provides improvements in vascular attenuation, subjective diagnostic quality, and detection of vascular injuries compared to conventional CT in trauma patients undergoing lower extremity CT angiography. MATERIALS AND METHODS: The IRB approved this HIPAA-compliant retrospective study. Informed consent was waived. Thirty-nine patients with acute lower extremity trauma including gunshot wounds (19 patients), falls (6 patients), motor vehicle accidents (5 patients), stab wounds (4 patients), pedestrian struck (2 patients), and unspecified trauma (3 patients) who underwent IV contrast-enhanced rsDECT angiography of the lower extremities on a rapid-kilovoltage-switching dual-energy CT scanner (Revolution CT, GE Healthcare) from 6/4/2019 to 1/14/2021 were studied. 7 patients were initially positive for vascular injury on conventional CT, while 32 patients were negative. Blended CT reconstructions simulating conventional 120 kVp single-energy CT, and rsDECT reconstructions (50 keV monoenergetic and iodine density maps) were reviewed. Region of interest contrast density measurements were recorded on conventional and 50 keV reconstructions at multiple levels from the distal aorta to the ankles and compared using Wilcoxon signed-rank tests. Vascular contrast density of 150 HU was used as a minimum cutoff for diagnostically adequate opacification. Images were interpreted by consensus for subjective image quality and presence of injury on both conventional and DECT reconstructions by two fellowship-trained abdominal radiologists blinded to clinical data, and compared using the paired McNemar test. RESULTS: Density measurement differences between conventional and rsDECT at every level of the bilateral lower extremities were statistically significant, with the average difference ranging from 304 Hounsfield units (HU) in the distal aorta to 121 HU at the ankles (p < 0.0001). Using a cutoff of 150 HU, 9.5% (93/976) and 3.1% of vascular segments (30/976) were considered non-diagnostic in the conventional and rsDECT groups, respectively, a reduction of 67.7% (p < 0.0001). Subjective image quality between conventional and rsDECT was not statistically significant, but there were 7 vascular segments out of a total of 976 segments across 3 different patients out of a total of 39 patients in which diagnostic quality was upgraded from non-diagnostic on conventional CT to diagnostic on rsDECT, all of which showed suboptimal bolus quality on conventional CT (unmeasurable in 4/7 and ranging from 56-146 HU in the remaining 3). Similarly, rate of injury detection was identical between conventional CT (15/39 patients) and DECT (15/39 patients). CONCLUSIONS: Vascular contrast density is statistically significantly higher with rsDECT compared to conventional CT, and subjective image quality was upgraded from non-diagnostic on conventional CT to diagnostic on rsDECT in 7 vascular segments across 3 patients. CLINICAL RELEVANCE: rsDECT provides greater vascular contrast density than conventional CT, with potential to salvage suboptimal examinations caused by poor contrast opacification.

Whole body CT for trauma reduces emergency department time for patients with lower extremity fractures.

BACKGROUND: Whole body CT in the setting of trauma has been shown to improve patient outcomes and decrease mortality in the emergency department (ED). Our institutional WBCT protocol allows for easy inclusion of the lower extremities, circumventing the need for diagnostic radiographs of the lower extremities. We hypothesized that this WBCT protocol would decrease time in the ED, reduce time to ED discharge, and decrease the number of lower extremity radiographs obtained in this patient population. PURPOSE: To assess patient throughput in the ED by determining total time in the ED, number of lower extremity radiographs, cost of radiographs, and total cost of imaging before and after the implementation of a WBCT protocol for trauma. METHODS: The trauma registry from an urban level 1 trauma center was searched for blunt trauma patients 6 months before and 6 months after the implementation of a WBCT protocol for trauma. Time between admission and discharge from the ED, total number of radiographs, total radiographs cost, total cost of ED imaging, and radiation dose estimations before and after WBCT implementation were calculated. RESULTS: There was a statistically significant decrease in time in the ED (76 min, p = 0.033) and number of lower extremity radiographs (decreased by 2 per patient, p < 0.01) following the implementation of the WBCT for trauma protocol. The cost of radiographs was decreased by 28.5% (p = 0.013) but the total cost of ED imaging was increased by approximately 4 × (p < 0.0001). Calculated effective radiation dose to the lower extremities increased by a factor of 1.9 × after implementation of WBCT for trauma. CONCLUSIONS: Implementation of a WBCT protocol for trauma resulted in statistically significant decreased time in the ED and decreased the number of radiographs at the expense of increased imaging costs and radiation exposure.

Imaging Review of Hockey-related Lower Extremity Injuries.

Hockey is a fast-paced contact sport with a high incidence of injuries. Although injuries are more frequent among elite players, recreational hockey injuries are a common issue faced by primary care and emergency physicians. Lower extremity injuries in hockey are particularly important because they account for approximately a third of all injuries and > 60% of all overuse injuries. This pictorial review provides the general and specialty trained radiologist with a knowledge of the patterns of lower extremity injury that occur in ice hockey.

Navigating the complexity of calf injuries in athletes: a review of MRI findings.

The calf muscle group is a common area for injury within the professional athlete population. Anatomical and biomechanical differences between the different component muscles vary their individual predispositions to and patterns of injury. However, there is a common unifying factor: injuries involving tendinous components have greater clinical implications with regards to rehabilitation, potential intervention, length of time to return to play, and re-injury rates. As such, accurate understanding of the underlying anatomy and subsequent interpretation of the injury patterns carry significant clinical ramifications. Ultrasound is a useful tool but has limitations, particularly when assessing soleus. As such, magnetic resonance imaging remains the workhorse in calf injury investigation.

Assessment of muscle volume using magnetic resonance imaging (MRI) in football players after hamstring injuries.

Muscle injuries of the hamstrings are among the most frequent in football and a main cause for significant time away from training and competition. The purpose of this study was to prospectively evaluate the loss of muscle volume in recreational football players three and six weeks after initial trauma. We hypothesized that significant muscle volume loss occurs within 6 weeks after the initial injury event. Twenty recreational football players (mean-age=25 ± 4years; mean-height=181 ± 8cm; mean-weight=81 ± 10kg) with type3a (minor partial muscle tear) and type3b (moderate partial muscle tear) injuries were included. Muscle volume was determined using established methods for the hamstrings and the quadriceps femoris muscle within 3 days and after 3 and 6 weeks following the initial injury. The injured hamstrings lost 6.5% (mean=64 cm3(95%CI=31-98 cm3), p<0.001), the healthy hamstrings lost 2.1% (mean=21 cm3(3-44 cm3),p=0.096) of muscle volume after six weeks. The quadriceps in the injured leg lost 3.8% (mean=78 cm3(51-104 cm3), p<0.001) and 4.5% (83 cm3 (45-121 cm3), p<0.001) in the healthy leg. Muscle volume loss inversely correlated with activity levels in the healthy leg for the quadriceps (r=0.96 (0.90-0.98); R2=0.92; p<0.001) and the hamstrings (r=0.72 (0.40-0.88); R2=0.51; p<0.001), as well as the quadriceps in the injured leg (r=0.70 (0.37-0.87); R2=0.49; p<0.001), but not the injured hamstrings. Muscle volume ratio of hamstrings to quadriceps in the control limb was 0.52 ± 0.06 and 0.53 ± 0.06 in the injured leg. The rehabilitation period of six weeks did not have a relevant negative or a positive effect on ratios. Significant muscle volume loss in the upper thigh occurs in recreational soccer players within three, and within six weeks after a hamstring injury and lies between 2% and 7%.

Predicting Noncontact Lower Limb Injury Using Lumbar Morphology in Professional Australian Football and Rugby League Players.

INTRODUCTION: Noncontact lower limb injuries are common within the Australian Football League (AFL) and National Rugby League (NRL). Smaller (<8.5 cm2) lumbar multifidus at the fifth vertebra (LM L5) and larger (>8.2 cm2) quadratus lumborum (QL) cross-sectional area (CSA) have been associated with increased noncontact lower limb injury risk in AFL players. These associations have not been explored in an NRL cohort. This study will attempt to replicate previous research findings by confirming that muscle morphology is associated with noncontact lower limb injury. METHODS: AFL (n = 87) and NRL (n = 151) players underwent LM L2-L5 and QL CSA ultrasound measures during preseason. Each club's medical staff reported all noncontact lower limb injuries sustained in the subsequent regular season. LM and QL CSA, age, body mass index, and noncontact lower limb injuries were analyzed using multivariable logistic regression. RESULTS: Seventy-two players sustained a noncontact lower limb injury in the 2020 regular season (AFL = 21, NRL = 51). The multivariable logistic regression (odds ratio (OR) = 1.36; 95% confidence interval (CI), 1.02-1.85; P = 0.038) identified AFL players with larger QL CSA at increased risk of sustaining a noncontact lower limb injury during the regular season, but no relationship was found for LM CSA and noncontact lower limb injuries in the AFL (OR = 1.01; 95% CI, 0.36-2.78; P = 0.591) or NRL (OR = 0.63; 95% CI, 0.29-1.33; P = 0.149). CONCLUSIONS: AFL players who sustained regular season noncontact lower limb injuries had larger QL CSA in preseason tests. No significant associations between either LM L5 CSA or LM L5 to QL ratio and regular season noncontact lower limb injuries were found.

Free gracilis end-to-side microanastomosis to a peronea arteria magna: a case report.

BACKGROUND: Complex orthoplastic lower limb trauma in individuals with multiple injuries requires considerable resources and interdisciplinary collaboration for good outcomes. We present the first reported end-to-side free flap microanastomosis for lower limb trauma reconstruction involving a peronea arteria magna without radiographic collaterals. CASE PRESENTATION: A 55-year-old Caucasian gentleman involved in road traffic collision sustained an open tibial fracture on the anteromedial distal third of the left lower leg with local degloving and a subtotal right foot and ankle degloving. Both injuries were reconstructed with free tissue transfer. A left lower limb peronea arteria magna successfully received a free gracilis muscle flap by end-to-side microanastomosis and perfusion of the foot was preserved. This rare anatomical variant and its anatomy is reviewed, as well as a description of the suggested preoperative planning and technique for reconstruction. CONCLUSIONS: Successful free flap reconstruction may be performed to a lower limb with a peronea arteria magna recipient as the lone vessel supplying the foot in trauma, although preoperative counseling of the risks, benefits, and options are essential. LEVEL OF EVIDENCE: Level V, case report.

Intratendinous hamstring injuries: sequential MRIs as a tool to reduce the risk of reinjury in elite sport.

Hamstring injuries are the most common muscle injuries in elite football. Injuries involving the intramuscular tendon are considered more significant, with longer return to play (RTP) times and an increased risk of reinjury. MRI is the gold standard investigation for muscle injuries, but initial findings cannot accurately determine RTP times. The role of MRI in monitoring muscle and tendon healing is not well described. We present three cases of hamstring injuries with intramuscular tendon involvement, illustrating the changes seen on MRI during progressive tendon healing and describing how we utilised this information to inform safe rehabilitation progression. We conclude that intramuscular hamstring tendon healing can be accurately seen on sequential MRI scans and that this information, when combined with traditional rehabilitation markers in and elite sport environment, can be utilised by clinicians to determine the earliest but safe RTP.

Quantification of immobilization-induced changes in human calf muscle using speed-of-sound ultrasound: An observational pilot study.

ABSTRACT: Short-term immobilization leads to fatty muscular degeneration, which is associated with various negative health effects. Based on literature showing very high correlations between MRI Dixon fat fraction and Speed-of-Sound (SoS), we hypothesized that we can detect short-term-immobilization-induced differences in SoS.Both calves of 10 patients with a calf cast on one side for a mean duration of 41 ±â€Š26 days were examined in relaxed position using a standard ultrasound machine. Calf perimeters were measured for both sides. A flat Plexiglas-reflector, placed vertically on the opposite side of the probe with the calf in-between, was used as a timing reference for SoS. SoS was both manually annotated by two readers and assessed by an automatic annotation algorithm. The thickness values of the subcutaneous fat and muscle layers were manually read from the B-mode images. Differences between the cast and non-cast calves were calculated with a paired t test. Correlation analysis of SoS and calf perimeter was performed using Pearson's correlation coefficient.Paired t test showed significant differences between the cast and non-cast side for both SoS (P < .01) and leg perimeter (P < .001). SoS was reduced with the number of days after cast installment (r = -0.553, P = .097). No significant differences were found for muscle layer thickness, subcutaneous fat layer thickness, mean fat echo intensity, or mean muscle echo intensity.Short-term-immobilization led to a significant reduction in SoS in the cast calf compared to the healthy calf, indicating a potential role of SoS as a biomarker in detecting immobilization-induced fatty muscular degeneration not visible on B-mode ultrasound.

Incidence and clinical impact of lower extremity vascular injuries in the setting of whole body computed tomography for trauma.

PURPOSE: The aims of this study are to determine the incidence of lower extremity fractures and/or vascular injuries in the setting of whole body computed tomography (WBCT) for trauma and to determine lower extremity injury outcomes in this patient population. METHODS: This is a retrospective observational study performed at a large urban Level 1 trauma center. Our institutional trauma registry was queried for patients who were evaluated with WBCT and lower extremity CT angiography (CTA) as a part of their initial imaging evaluation over a 43-month period. Patients with lower extremity fractures and/or vascular injuries were identified. Those patients with both lower extremity vascular injury and fracture were then analyzed to determine the physical relationship of the fracture to the vascular injury. Physical exam findings were extracted from the medical record. Interventions and long-term outcomes were determined from the medical record. RESULTS: A total of 370 patients met the inclusion criteria, with 98% experiencing blunt trauma. Of these, 290 (78.4%) were positive for lower extremity injury, including 266 (71.9%) with isolated fractures, 2 (0.6%) with isolated vascular injury, and 22 (5.9%) with vascular injury associated with long bone fracture. Of the 22 patients with combined fracture and vascular injury, 8 received vascular intervention and 10 had long-term complications as a result of their injuries. Physical exam findings were insufficient to diagnose 57% of the vascular injuries. CONCLUSIONS: The inclusion of lower extremity CTA as part of a WBCT imaging exam for trauma allows for the identification of vascular injuries that otherwise may have gone undetected or resulted in delayed diagnosis. Clinically occult lower extremity vascular injuries may be associated with poor outcomes.

Morel-Lavallée lesions (internal degloving injuries) of the lower extremity in the pediatric and adolescent population.

PURPOSE: To describe the largest case series of lower extremity traumatic internal degloving injury, i.e. Morel-Lavallée lesion (MLL) in the pediatric and adolescent population, its treatment and outcomes. METHODS: Retrospective review of patients under 18 years who presented with MLL to a tertiary children's hospital. Demographic, clinical, radiographic, treatment and outcomes data were collected. Descriptive statistical analysis was conducted. RESULTS: 38 patients having MLL with mean age 14.6 years were classified into two groups: hip/thigh MLL (nine patients) and lower leg MLL (29). Most common cause of lower leg and hip/thigh MLL was sports injury (79.3%) and motor vehicle accident (MVA) (33%) respectively. Most implicated sports were football and baseball. Primary care physicians/pediatricians were the initial treating providers for 63% of patients. Imaging modality of choice was magnetic resonance imaging (MRI) for lower leg MLLs (72.4%) and ultrasonography (US) for hip/thigh MLL (66.7%). Twenty-five (65.8%) patients were treated with conservative management, 12 (31.6%) with minimally invasive methods and 1 (2.6%) needed surgical management. Average return to normal activities took 14.3 and 9.1 weeks for hip/thigh and lower leg MLL, respectively. Twenty-four patients with adequate documentation demonstrated lower extremity functional score (LEFS) and pain level of 74/80 (92.5%) and 0.7/10, respectively, at mean 12.5 months follow-up. CONCLUSION: In contrast to adult injury literature, pediatric MLLs are more common in the leg/knee than hip/thigh region and caused mostly by sports injuries. Primary care physicians are the initial treating providers for the majority of the patients. Intervention is more often needed in the hip/thigh MLLs as opposed to non-operative management for lower leg injuries. This large case series on MLL in the pediatric population demonstrates differences in the management of hip and thigh lesions when compared to the management of the knee and leg lesions in the majority of these patients. Non-operative management in the majority of these lesions provided overall satisfactory outcomes.