Unusual approach to popliteal vein bypass graft stenosis following failed angioplasty in popliteal entrapment syndrome.

Popliteal artery entrapment syndrome (PAES) is where the popliteal artery is compressed-typically by the medial head of the gastrocnemius muscle. PAES is typically treated surgically with popliteal artery release with or without bypass. Graft stenosis is a recognised complication of vein grafts. These are normally treated endovascularly. Endarterectomy of venous graft stenosis may be a useful tool in selected cases, where an endovascular approach was unsuccessful. Long-term follow-up of graft stenosis endarterectomy will allow us to determine effectiveness of this method of treatment where other options have failed.

[An overview of treatment options for a rare disease, aneurysm of the popliteal vein, in connection with a case]. / Egy ritka kórkép, a vena poplitea aneurysma kezelési lehetoségeinek áttekintése egy eset kapcsán.

INTRODUCTION: Popliteal vein aneurysm is a rare, but potentially life-threatening condition that can lead to deep vein thrombosis and/or pulmonary embolism. It is often asymptomatic, but symptoms may include pain, post-thrombotic syndrome or chronic venous insufficiency. An experienced physician may be able to detect a palpable mass in the popliteal fossa. Duplex ultrasound is the first line of diagnosis. CT or MR venography play a role in the diagnosis. OBJECTIVE: To review the international literature, explain the possible treatment options, and present our case. CASE REPORT: A 62-year-old female patient had a recurrent pulmonary embolism while on direct-acting oral anticoagulant therapy. Duplex ultrasound and MR angiography were performed and confirmed a partially thrombosed aneurysm of the right popliteal vein. Aneurysm resection and venorrhaphy were performed as treatment. At follow-up, ultrasound showed adequate flow in the deep venous system. 6 months later, the control MR angiography showed good flow without stenosis. There were no postoperative complications. Discussion and literature review: The pathomechanism of the disease remains unclear. Treatment options are conservative therapy and/or surgical intervention, but there is no consensus regarding the therapy of symptomatic or asymptomatic cases. There is no clear statement regarding the method and duration of postoperative anticoagulant therapy. CONCLUSION: In the case of recurrent pulmonary embolism, the possibility of a popliteal vein aneurysm should be considered. Ultrasound is a non-invasive, widely available initial diagnostic tool. In addition to conservative treatment, the possibility of surgical intervention can be considered. The surgical procedure described in our case was successful. Orv Hetil. 2023; 164(39): 1544-1549.

Renal replacement therapy via popliteal vein for exhausted vascular access in emergency: A case report.

A 59 year-old man was admitted as his left antecubital arterio-venous fistula was thrombosed, and hemodialysis could not be succeeded for the last two sessions. It was a brachio-basilic fistula without transposition, which also required thrombectomy 8 months ago, and had been created 18 months before. He had multiple catheter insertions during the period of 6 years. Following the failed catheter insertions from both jugular and femoral veins, an ultrasound-guided venography via the left popliteal vein demonstrated the intact left popliteal and femoral vein with well-developed collaterals at the level of occluded left iliac vein. A temporary hemodialysis catheter was placed through the popliteal vein with an antegrade manner under ultrasound guidance in prone position, which effectively worked during hemodialysis sessions afterwards. Transposition of basilic vein was performed. Following the wound recovery, arterialized basilic vein has started to be used effectively for hemodialysis, and the popliteal catheter was displaced.

Cystic Adventitial Disease of the Popliteal Vein: A Case Report.

Venous cystic adventitial disease (VCAD) is a rare vascular anomaly located in the common femoral vein in most cases. We describe the case of a 59-year-old female patient with right leg edema who was misdiagnosed with deep vein thrombosis of the lower extremity at another hospital. Magnetic resonance angiography revealed a round mass in the popliteal vein, with a narrow lumen. Considering the location of the lesion, absence of a history of deep venous thrombosis and trauma, and clinical manifestations, the diagnosis is likely a popliteal vein adventitial cyst. Segmental popliteal vein resection and reconstruction were performed using a cylindrical great saphenous vein graft. No joint connection was found during the operation, and the postoperative pathology confirmed VCAD.

Popliteal vein reflux is associated with increased rates of thrombotic complications after small saphenous vein closure procedures.

BACKGROUND: Venous insufficiency in the small saphenous vein (SSV) is significantly less common than venous insufficiency in the great saphenous vein; the impact of popliteal vein reflux on SSV closure procedural outcomes has yet to be studied. METHODS: A retrospective analysis was performed on 150 SSV closure procedures from 2015 to 2019. Preoperative demographic analysis was performed, after which univariate analyses were performed for postoperative occlusion rates and combined rates of endothermal heat-induced thrombus (EHIT) and endovenous foam-induced thrombus (EFIT). RESULTS: The cohort had a mean age of 58 years, and 116 (77%) were female. Fifty-four patients had C2 disease, 76 had C3 disease, 15 had C4 disease, 1 had C5 disease, and 4 had C6 disease. Twenty-three patients (15.3%) were noted to have popliteal vein reflux on their initial venous insufficiency ultrasound study, compared with 127 (84.6%) who did not. Treatment modalities included 84 radiofrequency ablations (56.0%), 37 polidocanol endovenous microfoam (24.6%), and 29 laser ablations (19.3%). When comparing patients with popliteal vein reflux with those without, there was no significant difference in the occlusion rates at their immediate postoperative visit (99.2% vs 95.6%) or at their 6-month postoperative visit (92.1% vs 91.3%). EHIT/EFIT was noted in 4 of the 23 patients with popliteal vein reflux compared with 4 of the 127 patients without popliteal vein reflux (17.3% vs 3.1%; P = .01). All eight instances of EHIT/EFIT were classified as either arteriovenous fistula class I or II EHIT or EFIT, and all were successfully treated without progression to deep vein thrombosis. CONCLUSIONS: The presence of popliteal vein reflux has no impact on postoperative occlusion rates at 6 months; however, it is associated with a significantly increased rate in EHIT and EFIT. Patients should be counseled on this increased risk should they undergo SSV treatment with known popliteal vein reflux.

Contemporary management and outcomes of peripheral venous aneurysms: A multi-institutional study.

OBJECTIVE: Extremity venous aneurysms result in the risk of pulmonary embolism (PE) and chronic venous insufficiency. At present, owing to the rarity of these aneurysms, no consensus for their treatment has been established. The purpose of the present study was to review the presentation, natural history, and contemporary management of extremity venous aneurysms. METHODS: We performed a retrospective, multi-institutional review of all patients with extremity venous aneurysms treated from 2008 to 2018. A venous aneurysm was defined as saccular or fusiform with an aneurysm/vein ratio of >1.5. RESULTS: A total of 66 extremity aneurysms from 11 institutions were analyzed, 40 of which were in a popliteal location, 14 iliofemoral, and 12 in an upper extremity or a jugular location. The median follow-up was 27 months (range, 0-120 months). Of the 40 popliteal venous aneurysms, 8 (20%) had presented with deep vein thrombosis (DVT) or PE, 13 (33%) had presented with pain, and 19 had been discovered incidentally. The mean size of the popliteal venous aneurysms presenting with DVT or PE was larger than that of those presenting without thromboembolism (3.8 cm vs 2.5 cm; P = .003). Saccular aneurysm morphology in the lower extremity was associated with thromboembolism (30% vs 9%; P = .046) and fusiform aneurysm morphology with a thrombus burden >25% (45% vs 3%). Patients presenting with thromboembolism were more likely to have had a thrombus burden >25% in their lower extremity venous aneurysm compared with those who had presented without thromboembolism (70% vs 9%). Approximately half of all the patients underwent immediate intervention, and half were managed with observation or antithrombotic regimen. In the non-operative cohort, three patients subsequently developed a DVT. Eight patients in the medically managed cohort went on to require surgical intervention. Of the 12 upper extremity venous aneurysms, none had presented with DVT or PE, and only 2 (17%) had presented with pain. Of the 66 patients in the entire cohort, 41 underwent surgical intervention. The most common indication was the absolute aneurysm size. Nine patients had undergone surgery because of a DVT or PE, and 11 for pain or extremity swelling. The most common surgery was aneurysmorrhaphy in 21 patients (53%), followed by excision and ligation in 14 patients (35%). Five patients (12%) had undergone interposition bypass grafting. A postoperative hematoma requiring reintervention was the most common complication, occurring in three popliteal vein repairs and one iliofemoral vein repair. None of the patients, treated either surgically or medically, had reported post-thrombotic complications during the follow-up period. CONCLUSIONS: Large lower extremity venous aneurysms and saccular aneurysms with thrombus >25% of the lumen are more likely to present with thromboembolic complications. Surgical intervention for lower extremity venous aneurysms is indicated to reduce the risk of venous thromboembolism (VTE) and the need for continued anticoagulation. Popliteal aneurysms >2.5 cm and all iliofemoral aneurysms should be considered for repair. Upper extremity aneurysms do not have a significant risk of VTE and warrant treatment primarily for symptoms other than VTE.

A Popliteal Vein Aneurysm Accompanied by Lower Persistent Sciatic Vein.

Popliteal venous aneurysms (PVAs) are rare. Surgical treatment is recommended because of the risk of deep vein thrombosis and fatal pulmonary embolism. A persistent sciatic vein (PSV) is also a rare anomaly. We report a case of a PVA accompanied by a lower PSV. A 70-year-old man was admitted due to left leg heaviness. He had undergone ablation of both great saphenous veins 6 years prior to the admission. Duplex ultrasound showed a PVA on his left leg, which was 3.2 × 2.4 cm in size. The patient was treated with tangential aneurysmectomy with lateral venorrhaphy. His symptom gradually resolved. He received warfarin at a therapeutic range for 3 months. Duplex ultrasound at 6 months later showed no evidence of any recurrent aneurysm or venous reflux. His follow-up has revealed no complications for 18 months. Surgical treatment and perioperative therapeutic anticoagulation are recommended for treating PVAs. Tangential aneurysmectomy with venorrhaphy is the most common and the simplest surgical method.

Pulmonary embolism secondary to popliteal vein aneurysm: case report and literature review.

Aim: Aneurysms are rarely detected in the popliteal vein as only a few cases have been reported in the literature so far. However, such aneurysms can be fatal due to thromboembolic complications or rupture. Case presentation: A 47-year-old male who had multiple bilateral pulmonary embolisms secondary to saccular right popliteal vein aneurysm discovered by lower limb duplex ultrasound and successfully treated with tangential aneurysmectomy with venorrhaphy. Conclusion: Popliteal vein aneurysm should be ruled out as a cause of pulmonary embolism, and medical treatment should be started rapidly, but surgical management remains the gold standard.

Cannulation of the popliteal vein as an intraoperative emergency access in prone position: A case report.

Many surgeries have to be performed in the prone position. Access to central vessels is very limited in this position. This requires forward planning with regard to the placement of a central venous catheter. Emergency situations or unexpected intraoperative events in prone position are challenging, as a conventional central venous access is not possible. We describe the cannulation of the popliteal vein in such a case. We report the case of a patient with severe intracerebral hemorrhage who was transferred to our emergency department where his clinical condition rapidly deteriorated. Due to the surgical approach, a prone position was necessary and preoperative central venous cannulation was not possible. We therefore performed an alternative vascular access in prone position using a ultrasound-guided cannulation of the popliteal vein. The cannulation of the popliteal vein described here can be carried out as a quick and easy feasible alternative in emergency situations in prone position. The ultrasound-guided catheter insertion succeeded without any problems and there was no evidence of a deep vein thrombosis after the intervention.

Early Results of Popliteal Vein External Banding for Treatment of Chronic Venous Insufficiency.

BACKGROUND: Chronic venous insufficiency (CVI) encompasses a myriad of clinical manifestations including lower extremity swelling and pain, ulcerations and chronic skin changes such as stasis dermatitis, and lipodermatosclerosis. CVI effects greater than 25 million Americans and has a significant socioeconomic and psychosocial impact. Treatment of CVI varies depending on the etiology. For those patients with deep venous reflux, restoration of the deep venous valvular system is critical. Popliteal vein external banding is a novel technique to treat deep venous reflux. Our study aims to retrospectively review the early outcomes for the largest U.S. series of patients undergoing popliteal vein external banding. METHODS: Patients with C4, C5, and C6 disease with underlying deep venous reflux were treated with external banding of the popliteal vein. Basic demographic, ultrasound, and procedural data were collected. Patients were seen in clinic and underwent post procedure duplex. Procedure-specific complications were also assessed. The primary outcome was improvement of symptoms or wound healing. RESULTS: Twelve patients were identified. Seventy-five percent of patients had a history of DVT on the ipsilateral extremity and 66.7% (n = 6) of those patients had previous common or external iliac vein stenting for post-phlebitic syndrome. 58.3% of patients had active ulcerations (C6) at the time of popliteal vein banding and the mean VCSS score was 12.7, consistent with advanced venous disease. Patients were followed for a mean 8.62 months. Of the 8 patients that had active ulcers (C6), 75% completely healed with a mean time to healing of 3.3 months. 91.6% of patients reported clinical improvement in their symptoms (i.e., reduction in edema/swelling, pain or improvement in size of ulcer). Three patients had post-operative wound complications and 1 required oral antibiotic for associated cellulitis. CONCLUSION: Popliteal vein external banding represents a viable treatment modality for patients with venous insufficiency secondary to deep venous reflux. It is technically easier than most deep venous reconstructive options and may have an important role in the multimodal treatment of patients with advanced CVI.

Safety and feasibility report on nonimplantable endovenous valve formation for the treatment of deep vein reflux.

OBJECTIVE: Definitive treatment techniques for symptomatic deep venous reflux have been relegated to complex and invasive open surgery which is rarely performed today. The BlueLeaf System provides an endovenous method for the formation of deep venous valves without an implant, avoiding the complications associated with permanent foreign materials. The system has the adaptability to form valves within the femoral and popliteal veins at multiple levels in a single procedure. The aim was to determine the midterm safety and efficacy of this novel device in an early feasibility study. METHODS: Feasibility of endovenous deep venous valve formation was assessed in patients with chronic venous insufficiency (Clinical, Etiologic, Anatomic, Pathophysiologic [CEAP] 4-6). Follow-up was completed through 1 year, assessing vein patency and reflux time (RT) with duplex ultrasound examination. Venous clinical improvement was evaluated using the revised Venous Clinical Severity Scale. RESULTS: Of the 14 patients, 13 (93%) had successful formation of at least one monocuspid valve, with a mean number of 1.4 valves (range, 0-3 valves) per patient. There were no device-related serious adverse events during the index procedure. There were no deep venous thromboses reported at any time point, including 10 patients through the 1-year follow-up. In patients with at least one valve formed, site reported duplex ultrasound examination measured the average RT in the popliteal vein below valve formations, was 3.0 ± 1.0 seconds at baseline, 3.9 ± 3.1 seconds at 30 days, and 3.6 ± 2.1 seconds at 360 days. The revised Venous Clinical Severity Scale improved in all 13 successfully treated patients, decreasing from 15.0 ± 6.0 at baseline to 11.6 ± 5.5 at 30 days, 10.7 ± 5.3 at 210 days, and 9.4 ± 5.0 at 360 days (P = .0002; baseline to 360 days). Among the five patients with an ulcer who reached the 360-day follow-up visit, all (100%) healed at least one ulcer. Two patients (40%) healed all ulcers and three patients (60%) had a decrease in ulcers number but remained at C6 at 360 days. The five patients with a total of nine active ulcers at baseline had four active ulcers at 360 days. CONCLUSIONS: The BlueLeaf System holds promise as a minimally invasive means to safely form fully autogenous deep venous valves. Reconstructed deep veins remained patent, without deep venous thrombosis and symptomatic improvement was consistently observed; however, a decrease in the RT was not. Incremental device design improvements have been undertaken to improve valve function. The results of these iterations await further clinical evaluation.

Closed plication is a safe and effective method for treating popliteal vein aneurysm.

BACKGROUND: Popliteal vein aneurysms are a rare vascular anomaly first reported in the 1980s. Degeneration of elastic fibers and smooth muscle cell reduction, possibly secondary to inflammation, are implicated as integral steps in the development of these aneurysms. Given the rarity of this clinical entity, significant controversy exists regarding ideal treatment strategies, including the role of observation, medical management with anticoagulation, and surgical intervention. Retrospective reviews have demonstrated a failure rate of >40% with anticoagulation alone, with patients often presenting with pulmonary embolism. This has prompted our institutional preference for surgical management once the aneurysm is identified. Surgical management involves tangential repair with lateral venorrhaphy most commonly, followed in prevalence by aneurysm resection and end-to-end anastomosis either primarily or with vein interposition. Herein, we report our results with venous plications, through both closed and open techniques. METHODS: We performed a retrospective review of prospectively collected data for 10 patients undergoing popliteal vein plication for treatment of popliteal vein aneurysms. Patient-level characteristics and operative details were examined from periprocedural and follow-up records. RESULTS: We identified 10 patients undergoing popliteal vein plication, including 9 closed plications and 1 open plication. The average aneurysm size at presentation was 2.35 ± 0.69 cm for closed plication and 4.74 cm for the one open plication. After treatment, the average popliteal vein size was significantly reduced to 1.12 ± 0.45 cm for the closed plications (P < .001 from preprocedural size) and 1.13 cm for the open plication with 100% primary patency. Average follow-up for patients treated with closed plication was 35.0 ± 25.2 months, during which seven (78%) patients had a stable, normal popliteal vein size. One patient with recurrence was diagnosed with Klippel-Trénaunay syndrome. The other had degeneration of the popliteal vein cranial to the previous repair at 39 months after the original operation that required additional plication. The open plication patient experienced a hematoma requiring washout and resulting in a transient peroneal mononeuropathy. There was one case of cellulitis after closed plication but no hematomas within this group. CONCLUSIONS: Closed plication demonstrated favorable primary patency rates and low recurrence rates, avoiding technical issues or need for early institution of systemic anticoagulation associated with tangential repair and venorrhaphy or resection methods. Closed plication represents an attractive option in patients without luminal thrombus to limit the risk of these postoperative complications and obviates the need for bypass conduit and postoperative anticoagulation.

Popliteal Venous Aneurysm With Pulmonary Embolism: A Case Report.

Popliteal venous aneurysm (PVA) is defined as an increase in the diameter of the popliteal vein, twice its normal dimension. Herein, we report a case of right PVA with severe pulmonary embolism in a 75-year-old woman who presented with sudden chest tightness and dyspnea. Clinical examination revealed hypotension and hypoxemia. Radiographic investigations revealed extensive pulmonary embolism and right fusiform PVA. Following thrombolysis, her blood pressure and oxygen saturation normalized. However, she developed right calf swelling, and angiography revealed a thrombus in the right PVA, which was managed by catheter-directed thrombolysis. Thereafter, a vascular bypass was performed using the left great saphenous vein as a conduit to treat recurrent thrombosis. Subsequent venography indicated a patent vein graft, acceptable blood flow velocity, no thrombosis residue, and no significant thrombosis. Follow-ups at 3, 6, and 12 months revealed satisfactory outcomes. In conclusion, if the systemic condition is conducive, a surgical resection and reconstruction of the popliteal vein is recommended for the treatment of PVAs.

Early Results of Supporting Free Flap Coverage of Mangled Lower Extremities with Long Saphenous Arteriovenous Loop Grafts.

BACKGROUND: The ability to salvage the mangled lower extremity is both technically challenging and time consuming. It requires the collaborative efforts among multiple surgical specialties in addition to comprehensive post-traumatic wound follow-up. Our institution has integrated a dynamic effort among these specialists in the planning and facilitating a successful limb salvage program with creation of a mangled extremity algorithm. An integral part in this process is the vascular inflow to prepare coverage for large tissue defects lacking adequate recipient targets. Utilization of long saphenous arteriovenous (AV) loop has been cited with minimal data available using larger inflow vessels in the acute trauma setting. We performed a retrospective review and describe our early experience using our protocol with AV loop creation with free flap reconstruction to salvage traumatic leg injuries. Using the data, we sought to develop a mangled extremity protocol for trauma centers to guide mangled limb salvage. METHODS: Since June 2016, 398 patients were admitted to our level II trauma facility with isolated traumatic wounds to the lower extremities. Thirty-one limbs were deemed mangled in which 21 received primary amputations due to multiple factors. Ten patients admitted from the trauma service with isolated mangled lower extremities injuries were identified for review. All 10 patients sustained severe crush injuries with large soft tissue defects and decreased perfusion for healing but deemed salvageable by multispecialty assessment. Mangled extremity severity scores were tabulated. Patients age ranged from 21-44 years, with 8 men and 2 women. Repeated debridements until successful sterilization of the wounds were accomplished. Ten long saphenous vein AV loops were anastomosed to the at or above knee popliteal vessels for free flap reconstruction. All patients were followed post-AV loop creation for vascular complications and wound assessments. RESULTS: All 10 patients had sterilization of the wounds with repair of the fracture site before vascular reconstruction. Mean debridement to surgical site sterilization was 4.3 washouts (range 2-7). Successful AV loop creation with long saphenous vein was completed in 100% of patients without vascular complications nor steal events. Free flap tissue transfers directly connected to the loop were completed using 6 rectus abdominis, 3 latissimus dorsi, and 1 anterior thigh graft within 10 days of its creation. Patency rates of the AV loop was 100% with 10 successful flap transfers and 90% amputation free survival. One flap did not survive due to recurrent bacterial infection of the hardware. The 9 patients with successful procedures reached preoperative ambulatory status within 3 months after their final surgery. At 24 months follow-up, 90% amputation free survival is still maintained. CONCLUSIONS: Although a small patient cohort, utilization of long saphenous vein AV loop is successful as a bridge to free flap transfer for isolated mangled lower extremities. Development and incorporation of our mangled extremity protocol to guide limb salvage has proven successful in our early experience. Long-term data need to be complied to assess patency of the free flap transfer and quality of life outcomes.

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.

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.