Impact of ligation versus repair of isolated popliteal vein injuries on Deep Vein Thrombosis and Pulmonary Embolism incidence in trauma patients: a meta-analysis.

BACKGROUND: Traumatic injuries affecting the veins in the lower extremities have been correlated with both mortality and severe complications. Venous injuries are recognized as a contributing factor to the development of venous thromboembolism, commonly treated through procedures involving either vein ligation or repair. Despite previous efforts, substantial uncertainty remains when it comes to choosing between the execution of ligation versus various reparative techniques. The aim of this study was to evaluate the short-term results of surgically treating traumatic venous injuries through repair compared to ligation, specifically examining the resulting impacts on trauma patients in relation to DVT and PE occurrences. METHOD: A comprehensive search strategy was employed until August 10, 2023, to systematically explore Scopus and PubMed databases. Following the removal of duplicates, two researchers independently assessed the titles and abstracts of the identified studies. Only studies meeting the project's requirements and inclusion criteria, as evaluated through their full texts, were included in our investigation. Our study exclusively focused on original articles, specifically those involving human trauma patients with isolated popliteal vein injuries. Excluded from consideration were review articles, meta-analyses, cellular and molecular research, animal studies, case reports, case series, letters to the editor, posters, duplicates, and publications in languages other than English. The implementation of this systematic review and meta-analysis conformed to the standards delineated in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). RESULT: Conducting a thorough search, the inquiry identified 248 records. The assessment of titles and abstracts led to 51 studies that had the potential for eligibility. After reviewing the full texts of the chosen studies, 4 studies involving 1521 patients constituted the ultimate findings. CONCLUSION: We concluded that the ligation procedure had a higher incidence of pulmonary embolism compared to the repair of vein injuries, while the repair procedure had a higher incidence of deep vein thrombosis than ligation. Additional large-scale randomized controlled trials are still necessary to further support the findings of this meta-analysis.

Injury to the Popliteal Artery and Vein During Open Fibular Collateral Ligament Reconstruction: A Case Report.

CASE: We present a case involving a 26-year-old male who sustained an iatrogenic injury to the right popliteal artery and vein during open fibular collateral ligament reconstruction. The lesions were repaired immediately and required subsequent procedures on postoperative day 1. CONCLUSIONS: Iatrogenic vascular injuries during knee surgery can be devastating for patients and may lead to increased medical costs, unexpected hospital admissions, and additional surgical procedures. Surgeons should scrutinize preoperative imaging to identify the anatomic location of the popliteal artery and vein, which may be at risk during posterolateral knee reconstruction.

Adult Human Vein Grafts Retain Plasticity of Vessel Identity.

BACKGROUND: The spiral saphenous vein graft is an excellent choice for venous reconstruction after periphery vein injury, but only few cases have been reported. We implanted a segment of a single saphenous vein into both the popliteal vein as a venous vein graft and into the popliteal artery as an arterial vein graft at the same time in a trauma patient; we then had an extraordinary opportunity to harvest and examine both patent venous and arterial vein grafts at 2 weeks after implantation. METHODS: A spiral saphenous vein graft was made as previously described and implanted into the popliteal vein and artery as interposition grafts; because of the patient's serious injuries, an amputation was performed at day 18 after vascular reconstruction. The grafts were harvested, fixed, and examined using histology and immunohistochemistry. RESULTS: Both grafts were patent, and there was a larger neointimal area in the venous graft compared to the arterial graft. There were CD31- and vWF-positive cells on both neointimal endothelia, with subendothelial deposition of α-actin-, CD3-, CD45-, and CD68-positive cells. There were fewer cells in the venous graft neointima compared to the arterial graft neointima; however, there were more inflammatory cells in the neointima of the venous graft. Some of the neointimal cells were PCNA-positive, whereas very few cells were cleaved caspase-3 positive. The venous graft neointimal endothelial cells were Eph-B4 and COUP-TFII positive, while the arterial graft neointimal endothelial cells were dll-4 and Ephrin-B2 positive. CONCLUSIONS: The spiral saphenous vein graft remains a reasonable choice for vessel reconstruction, especially in the presence of diameter mismatch. Both the venous and arterial grafts showed similar re-endothelialization and cellular deposition; the venous graft had more neointimal hyperplasia and inflammation. At an early time, endothelial cells showed venous identity in the venous graft, whereas endothelial cells showed arterial identity in the arterial graft. CLINICAL RELEVANCE: Veins can be used as venous or arterial vein grafts but venous grafts have more neointimal hyperplasia and inflammation; vein grafts acquire different vessel identity depending on the environment into which they are implanted.

Anatomical Considerations of Infrageniculate Popliteal Artery Puncture: Alternative Pathway for Retrograde Access After Failed Re-entry.

BACKGROUND: A distal approach in endovascular procedures for revascularization of lowers limbs can be considered in case of no re-entry in subintimal recanalization. The aim of this study is to evaluate the feasibility of a medial approach to the infrageniculate popliteal artery (IPA) using existing computed tomography (CT) scan simulation and punctures performed on cadavers. METHODS AND RESULTS: CT angiographies of lower extremities were used to simulate IPA puncture and puncture trajectory. Tissues damaged during the trajectory between the puncture site and the access-related injuries were analyzed. Anatomical punctures on cadaverous model were also performed. Corpses were placed in supine position, the hip in slight flexion (40°) and abduction (external rotation of 60°). A 16 G needle was used for the IPA puncture. Twelve CT angiography simulations were made. Of these 12 simulations, 9 revealed an isolated lesion of the popliteal vein and 2 isolated lesions of the tibial nerve. A lesion of the tibial nerve and the popliteal vein on the same simulation was once observed. Damage to the medial gastrocnemius muscle could not be avoided in each case. Ten punctures were performed on cadavers with technical success. There were 6 popliteal vein lesions, 3 tibial nerve lesions, and 1 case without lesion. In all cases, damage to the medial gastrocnemius muscle was seen. CONCLUSIONS: This medial approach was feasible and is accompanied by trauma of elements of the popliteal pedicle. Preoperative CT angiography could anticipate best site of puncture and potential access-related injury.

Outcomes and Predictors of Popliteal Artery Injury in Pediatric Trauma.

BACKGROUND: Popliteal artery injury (PAI) is a rare occurrence in pediatric patients with significant consequences. Delays in diagnosis lead to severe complications such as lifelong disability and limb loss. We sought to identify outcomes and clinical predictors of PAI in the pediatric trauma population. METHODS: The Pediatric Trauma Quality Improvement Program (2014-2016) was queried for patients ≤17 years old with PAI. Patient demographics and outcomes were characterized. A comparison of patients sustaining blunt versus penetrating PAI was performed. A multivariable logistic regression analysis was used to identify predictors of PAI. RESULTS: From 119,132 patients, 58 (<0.1%) sustained a PAI with 74.1% from blunt trauma. Most of the patients were male (75.9%) with a median age of 15 and median Injury Severity Score of 9. A majority of the patients were treated with open repair (62.1%) in comparison to endovascular repair (10.3%) and nonoperative management (36.2%). The rates of open and endovascular repair and nonoperative management were similar between blunt and penetrating PAI patients (P = not significant). Concomitant injuries included popliteal vein injury (PVI) (12.1%), posterior tibial nerve injury (3.4%), peroneal nerve injury (3.4%), and closed fracture/dislocation of the femur (22.4%), patella (25.9%), and tibia/fibula (29.3%). Overall complications included compartment syndrome (8.6%), below-knee amputation (6.9%), and above-knee amputation (3.4%). The overall mortality was 3.4%. Patients with PAI secondary to penetrating trauma had a higher rate of concomitant PVI (26.7% vs. 7%, P = 0.04) and posterior tibial nerve injury (13.3% vs. 0%, P = 0.02) but a lower rate of closed fracture/dislocation of the patella (0% vs. 34.9%, P = 0.008) and tibia/fibula (0% vs. 39.5%, P = 0.004) compared to patients with PAI from blunt trauma. Predictors for PAI included PVI (odds ratio [OR] 296.57, confidence interval [CI] = 59.21-1,485.47, P < 0.001), closed patella fracture/dislocation (OR 50.0, CI = 24.22-103.23, P < 0.001), open femur fracture/dislocation (OR 9.05, CI = 3.56-22.99, P < 0.001), closed tibia/fibula fracture/dislocation (OR 7.44, CI = 3.81-14.55, P < 0.001), and open tibia/fibula fracture/dislocation (OR 4.57, CI = 1.80-11.59, P < 0.001). PVI had the highest association with PAI in penetrating trauma (OR 84.62, CI = 13.22-541.70, P < 0.001) while closed patella fracture/dislocation had the highest association in blunt trauma (OR 52.01, CI = 24.50-110.31, P < 0.001). CONCLUSIONS: A higher index of suspicion should be present for PAI in pediatric trauma patients presenting with a closed patella fracture/dislocation after blunt trauma. PVI is most strongly associated with PAI in penetrating trauma. Prompt recognition of PAI is crucial as there is a greater than 10% amputation rate in the pediatric population.

Analysis of Limb Outcomes by Management of Concomitant Vein Injury in Military Popliteal Artery Trauma.

BACKGROUND: Despite aggressive limb salvage attempts, military popliteal artery injuries are associated with high amputation rates. Combined arterial and venous injuries present a management dilemma for military surgeons in austere settings, and the impact of vein injury management strategy on limb outcomes is not clear. METHODS: Military casualties sustaining combined ipsilateral popliteal artery and vein injuries from 2003 to 2016 were identified from a military vascular injury database. Limbs were grouped based on whether venous ligation or repair was initially performed. The primary outcome was secondary amputation; the secondary outcomes included limb and vascular/graft complications. RESULTS: Fifty-six limbs were included; of which, 27 (48%) were managed with vein ligation and 29 (52%) with repair. Veins were repaired primarily in 13 (45%) cases with the remainder being treated with interposition grafts. Median injury severity score was higher in the ligation group (19 vs 15, P = 0.09), but vascular and concomitant limb injury characteristics were similar. Amputation rates did not differ by vein treatment (45% repair vs. 41% ligation, P = 0.76), and this held with injuries above and below the knee considered independently. Most (71%) amputations were performed <30 days from injury. Amputation was indicated more frequently for vascular repair failure in the ligated group (55% vs 15%, P = 0.04). Four graft infections were all in the repair group (P = 0.07 vs ligation). Arterial graft complications were more frequent with vein repair (45%) than ligation (30%), but this did not reach significance (P = 0.24). Only one deep vein thrombosis was diagnosed in each group (P = 0.96). CONCLUSIONS: Type of management of concomitant popliteal vein injury was not associated with early or late amputation in this series of military popliteal artery injuries. Vein injury management may have had implications for the development of arterial graft and limb complications, however. Surgical decision-making regarding popliteal vein treatment should balance short-term contingencies with long-term limb salvage issues.

Impact of ligation versus repair of isolated popliteal vein injuries on in-hospital outcomes in trauma patients.

BACKGROUND: Popliteal vascular injuries are common and frequently associated with limb loss. Although many studies have evaluated the treatment and outcomes of popliteal artery injuries (PAI), there is little available evidence regarding popliteal venous injuries (PVI). As such, substantial debate remains regarding the benefit of repair over ligation of PVI. The objectives of this study were to compare in-hospital outcomes of repair versus ligation of isolated PVI, as well as to determine nonvascular factors associated with worse outcomes. METHODS: Patients in the National Trauma Databank from 2007 to 2014 with at least one PVI were evaluated. First, patients with concomitant PVI and PAI were compared with patients with isolated PVI. Second, outcomes were compared between ligation and repair of isolated PVI. To limit the impact of concomitant injuries and focus on the impact of venous injury management, we defined isolated PVI as cases without concomitant PAI and with Abbreviated Injury Scale severity score of less than 3 for all body regions other than lower extremity. Patients dead on arrival and those with less than 18 years of age were excluded. The primary outcomes were in-hospital mortality, amputation, and in-hospital amputation-free survival (AFS). Secondary outcomes included lower extremity compartment syndrome, fasciotomy, acute kidney injury, pulmonary embolism, deep venous thrombosis, and inferior vena cava filter placement. RESULTS: Overall, 1819 patients (0.03%) had a PVI and after exclusion 1213 met the criteria for initial analysis. Of those, 308 had isolated PVI, and 905 had combined PVI and PAI. Patients with combined PVI and PAI had higher rates of amputation (15.2% vs 6.8%; P < .001), fasciotomy (64.5% vs 30.8%; P < .001), compartment syndrome (14.8% vs 8.8%; P = .006), and a lower AFS (82.9% vs 91.8%; P < .001) than patients with isolated PVI. There was no difference in in-hospital mortality, amputation, or in-hospital AFS between ligation and repair of isolated PVI. On multivariable logistic regression of isolated PVI, ligation was not independently associated with in-hospital AFS, amputation, or mortality. CONCLUSIONS: Ligation of isolated PVI was not an independent predictor of in-hospital mortality, lower extremity amputation, or in-hospital AFS. Ligation also did not result in higher rates of fasciotomy, acute kidney injury, or pulmonary embolism.

All-Inside Lateral Meniscal Repair via Anterolateral Portal Increases Risk of Vascular Injury: A Cadaveric Study.

PURPOSE: To compare the distance from the device tip to the neurovascular structures during an all-inside medial and lateral meniscal repair using anteromedial and anterolateral portals in a fresh-frozen cadaveric study. METHODS: Ten fresh-frozen cadaveric knees were studied. The popliteal artery, popliteal vein, and tibial nerve were identified after dissection via a posterior approach. An all-inside meniscal repair device was set to a 20-mm depth limit and inserted into a fixed point in the posterior horn at the meniscocapsular junction. This was performed for medial and lateral menisci via anteromedial and anterolateral arthroscopic portals. The distances between the device tip and the neurovascular structures were measured. We performed t tests to determine statistical significance. RESULTS: The distance between the device and popliteal artery was significantly closer when aimed at the posterior horn of the lateral meniscus via the anterolateral portal (4.7 ± 2.3 mm) versus the anteromedial portal (13.0 ± 8.0 mm, P = .010). The distance to the popliteal vein was closer via the anterolateral portal (6.7 ± 2.9 mm) versus the anteromedial portal (13.9 ± 5.8 mm, P = .004). For medial meniscal repair, the distance to the popliteal artery was significantly closer via the anteromedial portal (12.8 ± 11.3 mm) versus the anterolateral portal (23.8 ± 7.7 mm, P = .022). The distance to the popliteal vein was closer via the anteromedial portal (16.5 ± 11.3 mm) versus the anterolateral portal (28.3 ± 8.2 mm, P = .017). No significant difference was found in the distance to the tibial nerve when aimed at either meniscus via either portal. CONCLUSION: For all-inside meniscal repair, the popliteal vein is at risk and the popliteal artery is at high risk of injury when the posterior horn of the lateral meniscus is repaired via an anterolateral working portal. CLINICAL RELEVANCE: The popliteal artery and vein are at risk of injury when the posterior horn of the lateral meniscus undergoes all-inside repair via the anterolateral portal. Surgeons need to be aware of the risks when performing this repair.

Popliteal neurovascular bundle is safe during inside-out repair of medial meniscus without a safety incision.

PURPOSE: There is a theoretical risk of injury to neurovascular structures during inside-out meniscal repair without a safety incision, although there are limited studies assessing this risk. This simulation study on archival MRI films was performed to assess the risk for the popliteal neurovascular bundle and the peroneal nerve during passage of needles for inside-out meniscus repair without a "safety incision", thereby defining a "safe zone" of the menisci that can be safely repaired using this technique. METHODS: Archival MRI scans (n = 50) were retrieved and axial sections through the menisci were used for simulation. The needle passage was simulated for different points on the posterior horn and body of lateral and medial menisci at "half-hour" intervals using clock method (15° intervals) with three different portals and two different needle cannulas, resulting in six different scenarios of needle passage for each point on the meniscus. The distance of the needle in each scenario was measured from popliteal vessels (n = 50) and peroneal nerve (n = 10). The value "mean-3SD" was calculated for positive means and "Mean + 3SD" was calculated if the mean was negative. An additional 2 mm was defined as "safe distance". Thus, simulation models in which the mean - 3SD was less than 2 mm (or mean + 3SD was greater than - 2 mm for negative means) were labelled as "unsafe". RESULTS: Needle passage through medial meniscus at and medial to 1 o'clock position for a right knee (or 11 o'clock position for a left knee) was safe, irrespective of the portal and needle type. For the lateral meniscus, only the equatorial region was found to be safe with this method. CONCLUSIONS: The popliteal neurovascular bundle is safe during the inside-out medial meniscal repair without a safety incision. For the terminal-most part of the posterior horn, the AM portal and the straight cannula should be avoided. However, this method without safety incision cannot be recommended for lateral meniscus because of the risk to the popliteal vessels and the peroneal nerve. Instead, the inside-out method with a safety incision, or an all-inside method should be used for lateral meniscus. LEVEL OF EVIDENCE: III.

[Degenerative alterations of the afferent artery in long-functioning arteriovenous fistula]. / Degenerativnye izmeneniia privodiashchei arterii pri dlitel'no funktsioniruiushchem arteriovenoznom svishche.

Discussed in the article is the literature data on the background, causes, and mechanisms of the development of degenerative aneurysmatic transformation of the afferent artery in a long-functioning arteriovenous fistula. This is followed by presenting two own clinical case reports concerning the development of pronounced dilatation of arteries during 13 and 25 years of the existence of posttraumatic arteriovenous anastomoses, with a detailed description of the variants of surgical treatment of these patients.

[Post-traumatic concomitant popliteal artery pseudoaneurysm and arteriovenous fistula]. / Fistule artérioveineuse poplitée post-traumatique associée à un faux anévrysme.

Popliteal injuries are well known to be serious with a high rate of mortality due to damage caused to popliteal vessels. Pseudoaneurysm formation and arteriovenous fistulas are well-known complications of arterial injury, but are rarely concomitant. Diagnosis is usually done by computed tomography (CT) angiography. Treatment strategies consist of surgery or endovascular management. We report the surgical treatment of two cases of popliteal arteriovenous fistula associated with pseudoaneurysm complicating stab wounds.

Arteriovenous Fistula Formation After Intra-articular Injection Following Total Joint Arthroplasty.

Intra-articular joint capsule injection is a common method used to control postoperative pain as a result of primary total knee arthroplasty (TKA). It is generally considered a safe practice and is highly effective in reducing the need for postoperative opioid administration as well as decreasing recovery time through early mobilization. However, any injection into the posterior knee space has the potential to injure the vascular structures surrounding the knee. Iatrogenic formation of an arteriovenous fistula is a rare complication after TKA, and there are no reported cases of arteriovenous fistula formation as a direct result of intra-articular injection. This case report describes this complication that occurred several days after TKA. The patient had acute pain and swelling in the treated leg. An arteriovenous fistula of the popliteal artery and vein was identified with bilateral Doppler ultrasound and confirmed by angiogram. The most likely inciting event for the formation of the arteriovenous fistula was intra-articular injection of bupivacaine, which likely pierced the popliteal artery and vein, allowing the formation of the patent channel. The patient was treated successfully with stent placement through interventional radiology. Orthopedic surgeons performing intra-articular injections of the knee should refamiliarize themselves with the anatomy and location of the popliteal artery, use smaller-gauge needles, and aspirate the syringe before the injection to decrease the risk of iatrogenic damage to the vasculature or fistula formation. [Orthopedics.2016; 39(5):e976-e979.].

Popliteal vein repair may not impact amputation rates in combined popliteal artery and vein injury.

INTRODUCTION: This study aimed to determine the incidence, management, and outcomes of popliteal artery injury, popliteal vein injury, and concomitant popliteal artery injury and vein injury. METHODS: A retrospective analysis was completed using the 2000-2010 Nationwide Inpatient Sample utilizing International Classification of Diseases-9 codes to select patients with isolated popliteal artery injury (904.41), isolated popliteal vein injury (904.42), and isolated concomitant popliteal artery and vein injury (958.92). Variables included demographics, procedure type, and outcome during hospital course. Statistical analysis was with chi-square, Fisher exact test, and multivariate analysis. RESULTS: A total of 2216 patients presented with injury to the popliteal system; 71% (1568) presented with isolated popliteal artery injury, 14% (306) with isolated popliteal vein injury, and 15% (342) with concomitant popliteal artery and vein injury. Amputation was significantly increased in popliteal artery injury and concomitant popliteal artery and vein injury (P < 0.001) as compared to popliteal vein injury. Ligation of the vein was more common in concomitant popliteal artery and vein injury when compared to popliteal vein injury (P < 0.05). The rate of amputation was 9.8% for popliteal artery injury, significantly greater than for popliteal vein injury (0.7%, P < 0.001) but not different than for concomitant popliteal artery and vein injury (8.2%, P = NS). CONCLUSION: Evidence-based management of popliteal vasculature may increase rates of limb salvage. Within the limitations of the data set used, conclusions appear to be that patients with popliteal vein injury or concomitant popliteal artery and vein injury may be managed with vein ligation without increased amputation rates as compared to popliteal artery injury.

Popliteal artery dissection presented 12 hours after admission for a Salter III fracture of proximal tibia.

A 16-year-old boy sustained a salter III fracture of the upper tibia following a motorcycle accident. Except for well localized knee pain, the patient did not have any other symptom. Repeated clinical examination did not reveal any absent peripheral pulse. Given the state of the fracture, anatomical reduction and screw fixation was planned in the operating room.  Twelve hours after admission the patient was taken to the operating room. During the period preceding surgery he continued to have normal vascular clinical examinations. Further clinical assessment was performed in the operating room and remained to be normal. However after induction and upon extension of the lower limb, peripheral pulses in the affected side were abruptly lost. Urgent vascular exploration of the area showed a popliteal artery dissection necessitating a bypass graft to restore blood flow.  We present a review of the literature alongside a case report showing how popliteal artery pathology in a similar context can present late and be for a period of time clinically undetectable.

Management of traumatic popliteal vascular injuries in a level I trauma center: A 6-year experience.

INTRODUCTION: Popliteal vascular trauma remains a challenging entity, and carries the greatest risk of limb loss among the lower extremity vascular injuries. Operative management of traumatic popliteal vascular injuries continues to evolve. We aim at describing our experience with such complex injuries, with associated patterns of injury, diagnostic and therapeutic challenges, and outcomes. METHODS: From January 2006 to September 2011, 191 adult trauma patients presented to an urban level I trauma center in Miami, Florida with traumatic lower extremity vascular injuries. Variables collected included age, gender, mechanism of injury, and clinical status at presentation. Surgical data included vessel injury, technical aspects of repair, associated complications and outcomes. RESULTS: Forty-seven (24.6%) patients were diagnosed with traumatic popliteal vascular injuries. Mean age was 38.1 ± 16.1 years, and the majority of patients were males (43 patients, 91.4%). There were 21 (44.7%) penetrating injuries, and 26 (55.3%) blunt injuries. Vascular repair with saphenous venous interposition graft and PTFE (polytetrafluoroethylene) grafting were performed in 36 (70.7%) and 2 (3.9%) patients, respectively. Blunt popliteal injuries were significantly more associated with major tissue loss, and length of hospital and intensive care unit (ICU) stays. The risk for amputation is increased with longer ICU stays and the use of PTFE grafting for vascular repair. The overall mortality rate in this series was 8.5%. CONCLUSIONS: Blunt popliteal vascular injuries are associated with increased morbidity compared to penetrating trauma. Early restoration of blood perfusion, frequent use of interposition grafts with autogenous saphenous vein, and liberal use of fasciotomies play important role to achieve acceptable outcomes.

Hybrid treatment of arteriovenous fistula between popliteal vessels / Tratamento híbrido para fístula arteriovenosa entre vasos poplíteos

The authors describe treatment of a patient who presented an arteriovenous fistula between the popliteal vessels more than 20 years after a gunshot wound. The patient underwent endovascular treatment using Viabahn (Gore®) stent grafts, but, because of the large disparity in popliteal artery diameters proximal and distal of the fistula, the endovascular treatment was unsuccessful. The superficial femoral artery was then banded around the stent graft that was deployed previously. This improvised strategy allowed an open surgical approach to be performed far from the fistula site, reducing the risks of operating in a region with anatomic distortions and significant enlargement of the surrounding venous structures, which would certainly have increased the likelihood of iatrogenic injuries.

Os autores descrevem o tratamento de um paciente portador de fístula arteriovenosa entre vasos poplíteos com mais de 20 anos de evolução, após ferimento por projétil de arma de fogo. O paciente foi submetido a tratamento endovascular pelo implante de stents revestidos Viabahn (Gore®), porém o mesmo não foi bem sucedido devido à diferença de diâmetro entre a artéria poplítea proximal e a distal à fístula. A artéria femoral superficial foi submetida à cerclagem com fios de sutura ao redor do stentgraft previamente implantado. Esse recurso de improvisação permitiu uma abordagem distante do sítio da fístula, diminuindo os riscos do acesso cirúrgico em uma região com distorções anatômicas e vasos sanguíneos ectasiados, o que certamente acarretaria maior risco de lesões iatrogênicas.

Trap gun: an unusual firearm, aimed at wild animals but causing a silent epidemic of human fatalities.

Among a variety of uncommon firearms of different origin used worldwide, the trap gun used in Sri Lanka is underreported. This is an illegal, locally made, smooth-bore, long-barreled, muzzle-loading firearm with a victim-activated simple trigger mechanism. It is mainly used to protect crops and livestock from the potential harm by wild animals. Trap gun is mounted horizontally on pegs of sticks fixed to the ground. Miscellaneous metal pieces are used as ammunition. A small metal container filled with powdered matchstick heads/firecrackers covered by the striker surface of the matchstick box is used as the percussion cap. A metal hammer is set to hit the percussion cap. Through a lever mechanism, the hammer is kept under tension. The lever mechanism is connected to a trigger cord, which runs across the animal path. The first passerby, a human being or a wild animal, who accidentally trips the trigger cord and activates the trigger mechanism is critically injured. This characteristically damages the lower limbs of the human being. This communication highlights a death due to trap gun injury. The injury pattern caused by trap gun could overlap with that of shotgun and rifled firearm. A meticulous autopsy could sort it out.

Giant iliac vein aneurysm secondary to long standing traumatic popliteal arteriovenous fistula.

A 48-year-old man presented with a traumatic arteriovenous fistula (AVF) in the left popliteal space, due to a bullet injury 20 years back. A computed tomographic (CT) angiography revealed an AVF in the left popliteal space with an associated large iliac vein aneurysm (9.2 x 9.0 cms). Primary repair of the AVF was done. A Doppler scan showed marked reduction in the size of the aneurysm, 4 months after surgery. Cases associated with a venous aneurysm distant from the site of AVF are rare and there are only 7 cases reported in the international literature.