Anatomic variations of popliteal artery: Evaluation with 128-section CT-angiography in 1261 lower limbs

Incoherent optical fluctuation flowmetry for detecting limbs with hemodynamically significant stenoses in patients with type 2 diabetes

INTRODUCTION

The development of new highly accurate, inexpensive and accessible methods for the detection of lower-extremity peripheral artery disease (LE-PAD) in diabetic patients is required. The aim of this study was to evaluate the accuracy of a new incoherent optical fluctuation flowmetry (IOFF) method in detecting legs with hemodynamically significant stenoses compared to ankle brachial index (ABI) and transcutaneous oximetry (TcPO2) in patients with diabetes mellitus (DM).

MATERIALS AND METHODS

Patients were recruited into 2 groups. Group 1 included patients with DM without LE-PAD and/or diabetic foot syndrome; Group 2 included patients with DM and LE-PAD. All patients underwent the following measurements: ultrasound (reference method), ABI, TcPO2, and the new IOFF method.

RESULTS

The new IOFF method showed a sensitivity of 79.5% and a specificity of 89.8% in detecting limbs with hemodynamically significant stenosis (AUC 0.890, CI 0.822-0.957). TcpO2 allows the diagnosis of LE-PAD with 69.2% sensitivity and 86.2% specificity (AUC 0.817, CI 0.723-0.911). Using a standard ABI cut-off of less than 0.9, the sensitivity and specificity for this parameter were 34.5% and 89.7%, respectively. Increasing the diagnostic cut-off of the ABI on the study group to 0.99 improved sensitivity to 84.6% and specificity to 78% (AUC,0.824 CI 0.732-0.915).

CONCLUSIONS

The new IOFF technique has demonstrated high sensitivity and specificity in the detection of LE-PAD in patients with DM. The high accuracy, rapid measurement, and potential availability suggest that the new IOFF method has a high potential for clinical application in the detection of PAD.

Popliteal artery branching variations on computed tomography angiography of 1542 lower limbs and its associated factors

BACKGROUND

The identification of popliteal artery branching variation is of anatomical importance for surgical and endovascular procedures in the posterior region of the knee and below.

PURPOSE

To evaluate the variations and associated factors of popliteal artery branching by computed tomography angiography (CTA).

MATERIAL AND METHODS

CTA of the lower extremities of 1542 lower limbs in 771 patients (513 men and 258 women) were retrospectively reviewed to assess the popliteal artery branching patterns. The patient's sex, side of lower limbs, and population were recorded and evaluated for their association with popliteal artery branching patterns. P < 0.05 was considered to indicate statistical significance.

RESULTS

Variations in the branching of the popliteal artery were recorded in 9.3% of patients. The three most common variations were found to be hypoplastic-aplastic posterior tibial artery (PT) (3.6%), trifurcation (2.0%), and hypoplastic-aplastic anterior tibial artery (0.8%). A new pattern was detected in 2 (0.1%) cases, which were described as double PTs. Statistically significant differences were noted in the proportion of variation branching between the male and female groups (odds ratio = 1.52; 95% confidence interval = 1.07-2.16; P = 0.02).

CONCLUSION

The findings on popliteal variational branching patterns in the present study were in conformance to previous reports. Our study identified a novel variation of popliteal artery branching, which has not been mentioned in the literature so far. Sex was found to be an associated factor of branching variation.

A comparative analysis of anatomical variations of popliteal artery and its branches in concomitant aneurysmal disease

OBJECTIVES

Open or endovascular treatment of popliteal artery aneurysms (PAAs) is still debated. Data about the popliteal artery anatomy and its branches are essential to plan a surgical approach. The aim of this study was to report the anatomical variations of the popliteal artery and its branches in a population with aneurysmal disease and compare them with a standard population with non-aneurysmal disease.

METHODS

A retrospective review of consecutive patients who underwent surgical PAA repair in our center between January 2011 and December 2020 was performed. One-hundred-forty-six limbs in 128 patients underwent PAA treatment (Group 1). Computed tomography angiography images using a 128-section configuration were reviewed for anatomical variations of the popliteal artery and its branches. A control population of 178 limbs in 89 patients with non-aneurysmal disease was used to compare the outcomes (Group 2). All limbs were classified according to Kim's classification. The two groups were analyzed and compared by means of nonparametric Pearson chi-square test.

RESULTS

Both groups were homogeneous in terms of demographics, risk factors, and clinical presentation. In Group 1, the limbs with PAA were classified as type IA, 133 (91.1%); type IB, 2 (1.4%); type IC, 0; type IIA1, 1 (0.7%); type IIA2, 1 (0.7%); type IIB, 4 (2.7%); type IIC, 0; type IIIA, 3 (2.1%); type IIIB, 0; and type IIIC, 2 (1.4%). In Group 2 the limbs with non-aneurysmal disease were classified as type IA, 163 (91.6%); type IB, 5 (2.8%); type IC, 1 (0.6%); type IIA1, 1 (0.6%); type IIA2, 3 (1.7%); type IIB, 2 (1.1%); type IIC, 0; type IIIA, 3 (1.7%); type IIIB, 0; and type IIIC, 0. No difference in terms of anatomy of the popliteal artery and its branches was found between the two groups (P = NS).

CONCLUSIONS

Knowledge of anatomical variations of the popliteal artery and its branches is mandatory in case of the surgical approach. Anatomy in PAA patients is not different. Studies with larger population size are needed to validate these outcomes.

Anomalous Posterior Tibial Artery Course-Anatomic Considerations for the Posterolateral Ankle Approach: A Case Report

CASE

We report a unique anatomical case of an anomalous course of the posterior tibial artery found on dissection during the posterolateral approach to the ankle. To the best of our knowledge, no such case has been documented.

CONCLUSION

The vascular bundle consistent with that of the posterior tibial artery and vein was encountered in the far lateral aspect of the deep posterior compartment, which suggests physicians should proceed with caution when performing the posterolateral approach to the ankle so as to avoid iatrogenic injury of this named anatomic structure.

Lupus Anticoagulant and Anticardiolipin Antibody IgG are Associated with Increased Atherosclerosis at the Suprainguinal Elastic and Infrainguinal Muscular Arteries in the Abdomen and Lower Extremities

Purpose

Whether antiphospholipid antibodies (aPLs) cause atherosclerosis in certain arteries with specific compositions and locations remains unknown. We investigated the relationship between aPLs and their association with locations of atherosclerosis in the arteries of the abdomen and lower extremities.

Methods

Of 2273 patients, 697 who underwent computed tomography angiography of the abdomen and lower extremities and aPL evaluation were included. Atherosclerosis distribution score (ADS) was employed to quantify atherosclerosis severity. Multiple linear regression analysis was performed using the ADS of the suprainguinal elastic and infrainguinal muscular arteries as dependent variables and all aPLs, conventional risk factors of atherosclerosis, and coagulation-related factors as independent variables.

Results

In the suprainguinal elastic and infrainguinal muscular arteries, common risk factors for higher ADS were age, smoking, hypertension, higher glycated hemoglobin, male sex, decreased protein S, and increased homocysteine. Lupus anticoagulant (LA) and increased triglyceride level in the suprainguinal elastic arteries and anticardiolipin antibody (aCL) immunoglobulin (Ig)G, longer alcohol consumption duration, and increased fibrinogen level in the infrainguinal muscular arteries were also risk factors for higher ADS.

Conclusion

LA and aCL IgG were associated with atherosclerosis in the suprainguinal elastic and infrainguinal muscular arteries, respectively. aPLs could predict the location of atherosclerosis.

Analysis of the running position of the popliteal artery and branching level of the anterior tibial artery detected by magnetic resonance imaging to avoid vessel injury during surgery around the knee joint

Background

Vessel injuries during total knee arthroplasty or high tibial osteotomy are rare but have serious complications. This study aimed to analyze the running position of the popliteal artery (PA) and branching level of the anterior tibial artery (ATA), using magnetic resonance imaging (MRI). This analysis might be helpful in avoiding unnecessary vessel injury.

Methods

In total, 105 patients (41 men and 64 women), whose running position of the PA and branching level of the ATA could be detected by preoperative MRI, were included in this study. We configured zones A, B, C, and D to be 5–10, 15–20, 25–30 and 35–40 mm distal from the lateral tibial plateau in the axial view, respectively. First, the distance between the posterior cortex of the tibia and anterior border of the PA was measured. Second, the PA position from the medial border of the tibia was measured. This measured value was divided by the transverse diameter of the tibia, and multiplied by 100 to obtain the PA position from the medial border of the tibia. Third, the branching level of ATA was measured from the joint line. Subsequently, each value was compared between men (the M group) and women (the W group).

Results

The distance between the posterior cortex of the tibia and the anterior border of the PA was 5.5 ± 1.9, 10.4 ± 2.4, 12.5 ± 2.3 and 12.5 ± 2.3 (mm; mean ± SD) in zones A, B, C, and D, respectively. Comparing both groups, this distance was significantly larger (more separated posteriorly) in zones C and D in the M group. The PA position from the medial border of the tibia was 51.7 ± 6.5, 52.7 ± 8.2, 56.7 ± 10.5 and 66.8 ± 14 (%; mean ± SD) in zones A, B, C, and D, respectively. On comparing the two groups, this position was significantly larger (more laterally shifted) in zone D in the W group. The branching level of the ATA was not detected within 40 mm distal to the joint line in 92 patients (87.6%). However, it was detected within 40 mm (mean 32.5 mm; range 20–38) in 12 patients (11.4%). Among them, 11 were women. Only one woman had an aberrant branching pattern: the ATA bifurcated at the joint level.

Conclusion

The PA positioned closest at the joint level, gradually separated and shifted laterally towards the distal side. The distance between the posterior cortex of the tibia and the anterior border of the PA was closer in women than in men in zones C and D. Although a difference of 2 mm is small, the risk of PA injury can be considered to be higher in women than in men. Furthermore, ATA injury is also a concern during retraction of the tibialis anterior muscle posteriorly, and the descending cut of the tibial tuberosity, particularly in women.

Reporting lower extremity CT angiography for treatment planning

Diagnostic radiologists play an important role in the evaluation of patients presenting with signs and symptoms of lower extremity peripheral vascular disease, including critical limb ischemia in both acute and chronic settings, and intermittent claudication. The complications associated with tissue and/or limb loss related to acute limb ischemia and critical limb ischemia of the lower extremity make rapid diagnosis and early intervention critical in the management of these patients. Computed tomography angiography (CTA) is an effective, widely available, easily reproducible, non-invasive imaging modality that offers a rapid and accurate means to diagnose and grade the extent of vascular disease. However, CTA run-off reports are usually dictated in free text form, and referring and treating physicians may be unsure whether an anatomic structure has been evaluated if it has not been specifically mentioned in the report. In this article, the vascular anatomy and anatomic variants of the lower extremity, the most common lower extremity vascular pathologies are reviewed and clinically important CTA imaging findings are outlined. This provides a framework for radiologists to accurately evaluate lower extremity vascular pathologies and convey clinically relevant imaging findings for management by vascular surgeons or interventional radiologists.

Peroneal artery safe zone in the posterolateral approach to the distal tibia: A CT angiogram based anatomical study

OBJECTIVES

The posterolateral approach to the distal tibia is commonly used for stabilisation of ankle fractures as it allows good visualisation and direct reduction of the posterior distal tibia and malleolar fragments. This approach can also be used for internal fixation of an associated lateral malleolus fracture. The aim of our study is to describe the surgical anatomy of the peroneal artery (PA) in relation to the tibial plafond and the distal fibula; thereby suggesting a safe zone during proximal dissection of posterolateral approach.

METHODS

Using Computed Tomography Angiographic (CTA) study, the course of the PA in relation to the tibial plafond and distal fibula was analysed in 142 lower limbs (bilateral limbs of 71 adult patients; 43 males and 28 females). Axial, coronal, and sagittal CT sections were cross-linked to specify the position of the PA. The PA course was identified and the level of its distal bifurcation over the tibia was marked. Perpendicular measurements were made from this point to the tibial plafond and tip of distal fibula.

RESULTS

The PA bifurcated distally at mean 58.3±24.2mm (SD) (range: 37.0-115.0mm) proximal to the right tibial plafond and mean 81.9±24.4mm (range: 54.0-137.0mm) from the right distal fibular tip. In the contralateral side, the PA bifurcated at mean 57.9±23.3mm (range: 36.0-125.0mm) proximal to the left tibial plafond and 81.8±23.9mm (range: 54.0-147.0mm) from the left distal fibular tip. The difference between the right and the left side of distal bifurcation point diameter of the same patient was assessed, range (0.0-58.0mm) with median 2.0mm and IQR 10.0mm. Three different PA vasculature patterns were identified.

CONCLUSIONS

It is important for surgeons to be aware of the surgical anatomy of PA to avoid inadvertent injury during posterolateral approach to distal tibia. The PA may bifurcate as close as 36mm from the tibial plafond with possible variation bilaterally. Therefore, special attention needs to be considered by the operating surgeon while dissecting in this region due to the wide anatomical variation in vasculature. However, once the PA is mobilised, any fixation modality including posterior buttress plate could be safely performed.

Prevalence and characteristics of the aberrant anterior tibial artery: a single-center magnetic resonance imaging study and scoping review

Background

Planning surgical procedures of the lower leg benefits from considering the possibility of an aberrant anterior tibial artery (AATA), but previously published data on the frequency of this anatomic variant shows heterogeneity. We assessed the prevalence of AATA in a Latin American cohort using magnetic resonance imaging (MRI) and compared these with other studies reported in the literature.

Methods

We retrospectively included consecutive patients who had undergone multiplanar knee MRI at a radiology department in Lima, Peru. The MRI protocol included coronal T1 weighted, axial, sagittal and coronal proton density fat-saturated (PDFS) and sagittal T2 weighted images.

Two experienced radiologists assessed all images and were blinded to each other’s findings. The frequency of the AATA was compared to previous cohorts. A scoping review was undertaken to provide an overview of previously published data on the prevalence of ATAA.

Results

We analyzed 280 knee MRI examinations of 253 patients (median age 41 years (IQR 31–52), 53.8% male). The aberrant anterior tibial artery variant was present in 8 of 280 (2.9%) evaluated knees, resulting in a prevalence of 3.2% in our study population. The PDFS sequence in the axial or sagittal orientation was most effective to identify AATA. The frequency of AATA in the reviewed literature using different radiological modalities ranged from 0.4 to 6% (median 1%, IQR (0.5–2.3%).

Conclusions

The AATA is a frequent vascular variant that can be detected by MRI in the preparation of invasive interventions of the lower leg.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04801-9.

The congenital popliteal vasculature patterns in fibular free flap reconstruction by means of surgical anatomy in cadavers

Fibular free flap (FFF) is frequently used for reconstruction requiring vascularized bone. Thus, understanding its vasculature variation is crucial. This study investigates the popliteal artery branching variations in Thai cadavers and compares them with previous studies. One hundred and sixty-two legs from 81 formalin-embalmed cadavers were dissected. The popliteal artery branching patterns were classified. The previous data retrieved from cadaveric and angiographic studies were also collected and compared with the current study. The most common pattern is type I-A (90.7%). For the variants, type III-A was the majority among variants (6.2%). Type IV-A, hypoplastic peroneal artery, was found in one limb. A symmetrical branching pattern was found in 74 cadavers. Compared with cadaveric studies, type III-B and III-C are significantly common in angiographic studies (p = 0.015 and p = 0.009, respectively). Type I-A is most common according to previous studies. Apart from this, the prevalence of type III-A variant was higher than in previous studies. Furthermore, type III-B and III-C are more frequent in angiographic studies which might be from atherosclerosis. Thus, if the pre-operative CTA policy is not mandatory, the patients at risk for atherosclerosis and population with high variants prevalence should undergo pre-operative CTA with cost-effectiveness consideration.

Popliteal artery: Anatomical study and review of the literature

BACKGROUND

The frequency of appearance of anatomical variability in the terminal division of the popliteal artery (PA) is different according to the type of sample used, and ranges from 2% to 21%. The PA locates 1,01 cm behind to the lateral meniscus, which makes it vulnerable during surgical procedures. Iatrogenic injury of the PA or its terminal branches increases if anatomical variables are present. Our aim was to describe and review the branching pattern of the PA in a body-donors to science sample to determine the influence of the sample used (body-donors vs imaging test).

METHODS

A sample consisting of 260 popliteal regions, corresponding to 130 corpses (66 women, 64 men), have been dissected. Multivariate analysis was carried out.

RESULTS

The terminal division of the PA was classified as follows: Pattern 1: the PA divided into the anterior tibial (ATA) and the posterior tibial arteries (PTA) at the level or distal to the lower border of the popliteal muscle (PM) (94.7%). Pattern 2: the PA bifurcated into the ATA and PTA, proximal to the lower border of the PM (3.3%). Pattern 3: the PA divided at the same level into the ATA, PTA and PEA. (2%). No significant differences between gender and side of the limb could be find.

CONCLUSIONS

We propose a classification that encloses three identifiable groups only. This will allow clinicians to bear in mind these variables easily, at the same time avoiding injuries during surgical procedures such as lateral meniscus repair.

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.

Popliteal Artery Branching Variations: A Study on Multidetector CT Angiography

Determining the branching pattern of the popliteal artery (PA) is an important step in planning some radiological and surgical procedures. The aim of this study was to investigate the course and morphology of the terminal branches of the popliteal artery using multidetector computed tomography (MDCT) angiography, and also to determine possible role gender in branching pattern. Three-hundred forty lower extremity MDCT angiography images for 170 patients (118 M, 52 F), who were between 20–80 years old, were examined. Popliteal artery branching types were grouped as percentage incidences. TPT diameters and lengths in Type IA extremities were compared based on gender and right or left side. Anterior tibial artery (ATA), posterior tibial artery (PTA) and peroneal artery dominance rates were calculated. 5000 times measurement data was mixed so that the cascade mean filter values were calculated for the right and left TPT length each time. It was observed that Type IA was the most common branching pattern (89.4%). The variational pattern incidence was 10.6% and the most common category was Type III (4.1%). The most common pattern was Type IB (3.2%). Variational pattern was 2 times more prevalent in females when compared to the males. The mean TPT diameter was 4.5 mm (2.7–7.3 mm) and there was no difference based on gender and the right-left side. The most common dominant artery for the right and left legs was PTA in both genders. The cut-off values calculated for the right and left TPT independent of gender were 31.30 ± 2.40 and 28.36 ± 2.58, respectively. Three new subtypes were identified as short (S ≤ 2 cm), standard (N = 2–4 cm) and long (L ≥ 4 cm) in Type IA, since it is in a wide variational range although it is a typical PA branching pattern.

Endovascular treatment of diabetic foot ischemic ulcer - Technical review

This article is a technical review of the common techniques used in the treatment of lower-limb occlusive arterial disease associated with diabetes. The techniques described here reflect the author’s own practice and are methods that the author finds helpful in avoiding complications and in making the technical aspects of the procedures easier.

Variations in terminal branches of the popliteal artery: cadaveric study

INTRODUCTION

Identifying the branching pattern of the popliteal artery (PA) is a vital step in planning radiological and surgical procedures involving the anterior and posterior tibial and fibular arteries. The aim of this study was to characterize the course and morphology of the terminal branches of the PA.

MATERIALS AND METHODS

The anatomical variations in the branching patterns of the anterior and posterior tibial and fibular arteries were examined in 100 lower limbs fixed in a 10% formalin solution. A dissection of the popliteal region of the leg was carried out according to a pre-established protocol, using traditional techniques. Morphometric measurements were then obtained twice by two researchers.

RESULTS

In most cases (72%) the PA divides to form the anterior tibial artery (ATA) and a common junction for the posterior tibial and fibular arteries (type I), which further splits into the fibular artery and the posterior tibial artery (PTA). This type was subdivided into two subgroups according to whether the ATA (subgroup a) or the common junction of the posterior tibial and fibular arteries (subgroup b) had the larger diameter. Other identified variations included division of the PA into the ATA and PTA-8% (type II), trifurcation-12% (type III), the division of the PTA into the ATA and FA-8% (type IV), and aplasia of the PTA-8% (type IV).

CONCLUSION

Although the typical PA branching type was observed, it can be classified further into two additional sub-types based on the diameter of the ATA and the common junction of the posterior tibial and fibular arteries.

Differentiation of chronic total occlusion and subtotal occlusion of the femoropopliteal artery-role of retrograde flow sign and collateral circulation on CT angiography images

Objective:

To study the value of a retrograde flow sign and the collateral circulation on CT angiography (CTA) for the differential diagnosis of chronic total occlusion from subtotal occlusion of the femoropopliteal artery (FPA).

Abstract

50 patients with obstruction of the FPA underwent CTA and digital subtraction angiography examinations of the lower limbs. The frequency of a retrograde flow sign and collateral circulation on CTA in chronic total and subtotal occlusion was noted and analyzed, with the results of digital subtraction angiography as a standard to judge total or subtotal occlusion. The decreasing CT value from the distal to proximal direction on CTA suggests the existence of retrograde flow.

Results:

There were significant differences in the occurrence rates of a retrograde flow sign on CTA in the chronic total and subtotal obstruction groups (X² = 13.1, p < 0.05), as well as a collateral circulation sign (X² = 13.5, p < 0.05). Employing both the retrograde flow sign and the collateral circulation sign to diagnose chronic total obstruction of the FPA had a sensitivity of 92.3% and specificity of 89.8%.

Conclusion:

The retrograde flow sign combined with a collateral circulation sign is of great clinical value for differentiation of chronic total stenosis from severe stenosis (subtotal occlusion) of the FPA.

Advances in knowledge:

A retrograde flow sign combined with a collateral circulation sign is of great clinical value to differentiate between chronic total stenosis and severe stenosis (subtotal occlusion) of the FPA.

Evaluation of popliteal artery branching patterns and a new subclassification of the 'usual' branching pattern

PURPOSE

To determine the frequency of popliteal artery branching variations in a wide study cohort and to investigate the relationship between these variations and infrapopliteal peripheral arterial disease (PAD). A subclassification was proposed for the most encountered type I-A, utilizing tibio-fibular trunk (TFT) length.

METHODS

A total number of 1184 lower extremity digital subtraction angiography (DSA) studies of 669 patients were evaluated. Following exclusion, 863 lower extremity DSA studies (431 right, 432 left) of 545 patients were enrolled. Popliteal artery branching type, patency of anterior tibial artery (ATA), fibular artery (FA) and posterior tibial artery (PTA) in each extremity and TFT length for type I-A extremities were recorded. Percentages of branching patterns, mean length and cut-off value of TFT and incidence of PAD in different types of branching were calculated.

RESULTS

Type I-A was the most common type of branching (81.3%). Frequency of branching pattern variation was 18.7%, the most common variation category was category III (12.2%) and the most common variation type was type III-A (5.6%). ATA and PTA had higher percentages of PAD in extremities with variant branching types. Cut-off value of 3 cm for TFT length was proposed in order to subclassify type I-A.

CONCLUSIONS

Our study cohort presents a higher incidence of popliteal artery branching variations. Some branching variations might have effect on the involvement pattern of the infrapopliteal arteries by PAD. We propose a subclassification for type I-A; type I-A-S (TFT < 3 cm) and type I-A-L (TFT ≥ 3 cm) which might have impact on interventional procedures.