GAE Anatomy Considerations

Genicular Artery Embolization: A Review of Essential Anatomic Considerations

Given the nature of this featured article, a pictorial summary rather than a text summary is provided here.

Take away point

Genicular artery embolization is increasingly recognized as a safe and effective treatment option for symptomatic knee osteoarthritis and recurrent hemarthrosis after total knee arthroplasty. Genicular arteries are an essential contributor to vascular supply for the knee joint and demonstrate considerable variability.

Reference

Liu, S., Swilling, D., Morris, E.M., Macaulay, W., Golzarian, J., Hickey, R. and Taslakian, B., 2023. Genicular Artery Embolization: A Review of Essential Anatomic Considerations. Journal of Vascular and Interventional Radiology.

Click here for abstract

Study design

Review

Funding Source

None

Setting

Academic

Figure

Figure 1 A schematic diagram showed the descending genicular artery (1), saphenous branch (2), articular branch (3), superior lateral genicular artery (4), superior medial genicular artery (5), middle genicular artery (6), inferior lateral genicular artery (7), inferior medial genicular artery (8), and anterior tibial recurrent artery (9).



Figure 2 A 61-year-old person with osteoarthritis. Digital subtraction angiography (DSA) from the superficial femoral artery. Frontal view showed the descending genicular artery (1), saphenous branch (2), articular branch (3), superior lateral genicular artery (4), superior medial genicular artery (5), medial sural artery (S), inferior lateral genicular artery (7), and inferior medial genicular artery (8).



Figure 3 A 50-year-old person with osteoarthritis. Angiographic findings of the descending genicular artery. In the frontal view, the descending genicular artery arose medially from the superficial femoral artery and bifurcated into an articular branch (1) and common trunk of the muscular branch (2) and saphenous branch (3). The articular branch ramified into a subsegmental articular branch (4) supplying the patellofemoral space and a subsegmental articular branch (5) supplying the medial tibiofemoral joint space.



Figure 4 A 50-year-old person with osteoarthritis. Variant descending genicular artery branching pattern with angiography performed from the superficial femoral artery. The descending genicular artery bifurcated into a saphenous (1) and articular branch (2) with an inverted “Y” shape. The muscular branch (3) arose directly from the superficial femoral artery.



Figure 5 A 68-year-old person with osteoarthritis. Digital subtraction angiography (DSA) of the superior lateral genicular artery in the frontal projection showed a cutaneous branch (1), superficial patellar branch (2), deep branch (3), articular branch (4), middle genicular artery arising from a common trunk with the superior lateral genicular artery (5), and collateralization with the inferior lateral genicular artery (6).



Figure 6 A 61-year-old person with osteoarthritis. There was a common origin of the superior medial genicular artery (1) and middle genicular artery (2). The superior medial genicular artery ran along the medial femoral condyle toward the medial tibiofemoral joint.



Figure 7 A 68-year-old person with osteoarthritis. Angiography performed from the articular branch of the descending genicular artery when there was an absent or diminutive superior medial genicular artery demonstrated branches (white arrows) supplying territory usually perfused by the superior medial genicular artery and retrograde opacification of the superior lateral genicular artery branches (black arrows).



Figure 8 A 68-year-old person with osteoarthritis. Variant origin location of the inferior lateral genicular artery (ILGA). The inferior medial genicular artery (1) and ILGA (2) shared a common trunk off the popliteal artery near the joint line. The ILGA gave off a muscular (3) and fibular branch (4).



Figure 9 A 67-year-old person with osteoarthritis. Angiography of the inferior medial genicular artery (1) showed supply of the medial tibiofemoral joint with hypervascularity prior to embolization.



Figure 10 A 67-year-old person with osteoarthritis. Course of the middle genicular artery with a variant origin. The middle genicular artery (1) shared a common trunk with the superior lateral genicular artery (2) and coursed inferiorly.



Figure 11 A 68-year-old person with osteoarthritis. There was robust collateralization between the anterior tibial recurrent artery (1) and inferior lateral genicular artery (2).



Figure 12 A 75-year-old person with osteoarthritis. There was a common origin (1) of the sural artery (2) and inferior lateral genicular artery (3) arising off the posterior aspect of the popliteal artery. There was also a variant origin of the inferior medial genicular artery (4) arising from the tibioperoneal trunk.



Figure 13 A 61-year-old person with osteoarthritis. Robust collateralization of the genicular arteries. Injection from the inferior medial genicular artery (1) showed collateralization with the articular branch of the descending genicular artery (2).



Figure E1 A 68-year-old person with osteoarthritis. Digital subtraction angiography (DSA) from the superficial femoral artery. Lateral view showed the sural artery (1), superior lateral genicular artery (2), common trunk of the inferior medial genicular artery and inferior lateral genicular artery (3), inferior medial genicular artery (4), and inferior lateral genicular artery (5). A = anterior; P = posterior.



Figure E2 A 50-year-old person with osteoarthritis. Angiographic findings of the descending genicular artery. In the lateral view, the articular branch (1) coursed anteriorly. The saphenous branch (2) was, by comparison, more posterior and ran with the distribution of the saphenous nerve. The saphenous branch extended inferiorly with collateralization to the cutaneous branches of the inferior medial genicular artery (3). A = anterior; P = posterior.



Figure E3 A 50-year-old person with osteoarthritis. Descending genicular artery branching pattern with angiography performed from the descending genicular artery. The articular branch (1) was lateral to the saphenous branch (2). A diminutive muscular branch (3) supplying the vastus medialis arose from the proximal articular branch. Numerous cutaneous branches (open arrows) that extended to the skin originated from the saphenous branch.



Figure E4 A 67-year-old person with osteoarthritis. Digital subtraction angiography (DSA) of the superior lateral genicular artery in the lateral view showed the musculocutaneous branch (1), cutaneous branch (2), articular branch supplying the patellofemoral joint (3), and reflux into the sural (4) and popliteal (5) arteries. A = anterior; P = posterior.



Figure E5 A 67-year-old person with osteoarthritis with no identifiable superior medial genicular artery on angiography from the popliteal artery. Angiography from the superior lateral genicular artery demonstrated cross midline continuation of the superior lateral genicular artery to supply the superior medial genicular artery territory (circle). Additionally, there was retrograde opacification of the inferior lateral genicular artery (1).



Figure E6 A 68-year-old person with osteoarthritis. Variant origin location and angulation of the inferior lateral genicular artery. Low origin of the inferior lateral genicular artery (1) from the distal segment of the popliteal artery with collateral branches (2) to the superior lateral genicular artery (3).



Figure E7 A 50-year-old person with osteoarthritis. Angiographic findings of the inferior medial genicular artery. Injection of the inferior medial genicular artery (1) demonstrated retrograde opacification of the descending genicular artery’s articular (2) and saphenous (3) branches.



Figure E8 A 61-year-old person with osteoarthritis. Course of the middle genicular artery with a variant origin. The middle genicular artery (1) shared a common trunk with the superior medial genicular artery (2) and coursed inferiorly to enter the posterior aspect of the tibiofemoral joint. A = anterior; P = posterior.



Figure E9 Room setup with patient positioned on the fluoroscopy table with the target knee at the isocenter. The nontreatment knee was positioned as close to the edge of the table as the patient could tolerate comfortably to reduce overlap on various angulation and artifact during cone-beam computed tomography (CT). (a, b) The procedure table was set up perpendicular to the fluoroscopy table at the level of the groin access so that the used microcatheter and wire could be easily rested on the table. (c) The proceduralist stood on the cranial or caudal side of the table depending on the laterality of the target knee. A separate smaller embolization stable was set up to help avoid contamination of the equipment with embolic material (not shown).



Figure E10 A 75-year-old person with osteoarthritis. There was a common origin (1) of the sural artery (2) and inferior lateral genicular artery (3) arising off the posterior aspect of the popliteal artery. There was also a variant origin of the inferior medial genicular artery (4) arising from the tibioperoneal trunk. A = anterior, P = posterior.



Figure E11 A 61-year-old person with osteoarthritis. Robust collateralization of the genicular arteries. Injection from the inferior lateral genicular artery (1) showed collateralization with the articular branch of the descending genicular artery (2).

Commentary

This review discusses the genicular arteries and advises avoiding certain branches during genicular artery embolization (GAE) when possible. However, there are limitations to consider. While some outcomes of embolizing cutaneous branches are described, there's limited data on the clinical implications or chronic effects of nontarget embolization. Anatomic descriptions are based partly on cadaveric data, which may not fully represent GAE patients. The inflammatory state in GAE patients may lead to larger branch sizes and altered anatomy. Furthermore, genicular artery anatomy might change in patients who undergo GAE for hemarthrosis after total knee arthroplasty. Despite these limitations, understanding knee vascular supply is crucial for successful GAE and reducing nontarget embolization risk. Practicing good clinical technique by embolizing distal to tissue-supplying branches and assessing anastomoses presence may help minimize adverse events.

Glenohumeral Artery Embolization: the next frontier of MSK embolization?

Transarterial Embolization for Adhesive Capsulitis of the Shoulder: Midterm Outcomes on Function and Pain Relief

Clinical question

Is transarterial embolization for adhesive capsulitis of the shoulder safe and effective?

Take away point

Transarterial embolization for adhesive capsulitis of the shoulder is safe, effective, and with long-lasting clinical improvements.

Reference

Lanciego, C., Puentes-Gutierrez, A., Sánchez-Casado, M., Cifuentes-Garcia, I., Fernández-Tamayo, A., Dominguez-Paillacho, D., Ciampi-Dopazo, J.J. and Marquina-Valero, M.A., 2024. Transarterial Embolization for Adhesive Capsulitis of the Shoulder: Midterm Outcomes on Function and Pain Relief. Journal of Vascular and Interventional Radiology, 35(4), pp.550-557.
Click here for abstract

Study design

Prospective, observational, descriptive study

Funding Source

None

Setting

Academic

Figure

Figure 4(a) Pre-embolic angiogram in the late arterial phase showed areas of hyperemia in territories dependent on the thoracoacromial and anterior humeral circumflex arteries (white arrowheads). (b) Postembolic angiogram showed resolution of the hyperemia after embolization with imipenem/cilastatin sodium (black arrowheads).

Summary

Adhesive capsulitis, commonly known as frozen shoulder, is a condition characterized by pain and progressive loss of both active and passive shoulder mobility, leading to functional disability. While most cases respond to conventional treatments such as physical therapy and medication, about 30% of cases remain refractory to these interventions, resulting in chronic symptoms. Recent studies have explored the role of increased vascularization in adhesive capsulitis and have evaluated the effectiveness of transarterial embolization (TAE) in treating refractory cases by occluding arterioles to reduce inflammation and pain.

This prospective study, conducted from January 2018 to May 2023, involved embolizing arterioles in patients with MRI-compatible adhesive capsulitis and persistence of symptoms for more than 3 months who had not responded to standard treatment. Participants were selected based on clinical and magnetic resonance imaging criteria. Exclusion criteria included patients under 18, those with systemic diseases, shoulder fractures, or a history of shoulder surgery. The embolization procedures were carried out by experienced interventional radiologists and involved arteriography to identify the hypervascular arterial supply to the shoulder capsule (early vascular filling, hyperemia, anomalous vessels, or early venous return,), followed by selective catheterization and embolization using small amounts (0.2–0.4 mL) of suspended microparticles (10–70 μm) formed by diluting a mixture of 500-mg imipenem (IMP) and 500-mg cilastatin sodium (CS) (Aurovitas, Teramo, Italy) in 5–10 mL of iodinated contrast. Embolization endpoint was complete or nearly complete stasis. Safety was assessed by recording adverse events, and effectiveness was measured by improvements in pain and range of motion over a 6-month period post-procedure followed by monthly interview by rehabilitation physicians.

The study included 20 patients, with 60% being women, 95% right-handed, and 30% having diabetes. Significant improvements were noted in shoulder mobility and function, as well as reductions in various types of pain, especially nocturnal pain. No significant adverse events were reported, and most patients experienced sustained benefits, with 70% reporting cessation of analgesic use during long-term follow-up. However, diabetic patients had a less favorable long-term response as they continue to require analgesics.

Musculoskeletal embolization, aiming to break the circle of hypervascularization, pain, and inflammation, is emerging as a potential treatment for inflammatory musculoskeletal conditions refractory to conventional therapy. This study's findings support the safety and effectiveness of TAE, with significant improvements in pain and shoulder mobility observed early on and maintained over time. The use of IMP/CS as an embolic agent appears to be safe, with a low rate of adverse events. While the study adds valuable information to the field, limitations such as a small sample size and lack of a control group suggest a need for larger, multicenter studies with longer follow-up periods to further validate the long-term effectiveness and establish TAE as a standard treatment option for adhesive capsulitis.

Commentary

This article presents a study investigating the use of transarterial embolization as a treatment for adhesive capsulitis (frozen shoulder), which is a condition causing pain and restricted movement in the shoulder. The results suggest that embolization is a safe procedure that can offer significant relief from pain and functional disability in patients with adhesive capsulitis. Clinicians and healthcare professionals could benefit from understanding the potential of transarterial embolization as an alternative treatment for adhesive capsulitis, particularly in cases where standard therapies are ineffective. However, to integrate this knowledge into clinical practice, additional information such as standardized protocols, long-term outcomes validation, comparison with other treatments, and specific considerations for patient selection (e.g., the impact of diabetes on treatment efficacy) would be valuable. Trans-arterial embolization may be considered in the management pathway of shoulder adhesive capsulitis.

Combating Steal: Percutaneous Interventions for Dialysis Access Steal Syndrome

Percutaneous Management of Dialysis Access Steal Syndrome: Interventions and Outcomes from a Single Institution’s 20-Year Experience

Clinical question

To evaluate the outcomes of percutaneous interventions in Dialysis Access Steal Syndrome and assess their safety and effectiveness .

Take away point

Percutaneous interventions in patients with Dialysis Access Steal Syndrome was demonstrated to provide symptomatic improvement, and decrease the need for follow up surgical intervention.

Reference

Rigsby DC, Clark TWI, Vance AZ, Chittams J, Cohen R, Mantell MP, Kobrin S, Trerotola SO. Percutaneous Management of Dialysis Access Steal Syndrome: Interventions and Outcomes from a Single Institution's 20-Year Experience. J Vasc Interv Radiol. 2024 Apr;35(4):601-610. doi: 10.1016/j.jvir.2023.12.566. Epub 2024 Jan 1. PMID: 38171415.

Click here for abstract

Study design

Retrospective single institutional study

Funding Source

None reported

Setting

Academic: Perelman School of Medicine, University of Pennsylvania

Figure

Figure 1. Flow diagram describing patient progression from initial dialysis access steal syndrome (DASS) evaluation by a referring surgeon to interventional radiology (IR) percutaneous study with or without intervention to follow-up. DRAE = distal radial artery embolization.

Summary

 
Dialysis access steal syndrome (DASS) occurs when blood flows preferentially through the dialysis access circuit, depriving downstream tissues of oxygen-rich blood. This can lead to pain, ulcers, and tissue loss in the ipsilateral limb in up to 10% of dialysis patients. Known risk factors for DASS include older age, female sex, diabetes mellitus, coronary artery disease and peripheral arterial disease. Fistulography is recommended for initial diagnostic workup of DASS and can define the vascular anatomy and assess the degree of intervention required. Percutaneous interventions like distal radial artery embolization and minimally invasive ligation endoluminal-assisted revision percutaneous banding procedure can be performed and are described as the percutaneous equivalents to open surgeries, which include surgical access banding, distal revascularization with interval ligation, and distal radial artery ligation. Access ligation, which is the definitive treatment, is used sparingly due to the importance of maintaining hemodialysis access. Data on the clinical performance of percutaneous interventions is limited.

This study used data from a single institution over a period of 20 years. A retrospective chart review was performed for the 212 patients with 286 fistulograms meeting the inclusion criteria. Patient symptoms were recorded, flow through the access was quantified using a flow measurement (ReoCath, Transonic) catheter and categorized via the 2019 Kidney Disease Outcomes Quality Initiative. Each case fell into one of two categories: diagnostic fistulogram alone or undergoing fistulogram plus intervention. Technical success of the procedure was measured by reporting standards published by the Society of Interventional Radiology and clinical success by any reported improvement in DASS symptoms at the next follow up visit. Patients with severe ischemic tissue loss who received prompt surgical intervention were excluded.

The authors used a multiple logistic regression model to analyze the data, investigating the associations between DASS intervention and major adverse events, access preservation, and follow up surgery. Access was considered not preserved if follow up visit notes contained any indication of access abandonment or takedown. Covariates that were used in the regression model were female sex, upper arm access location, graft access type, diabetes mellitus, coronary artery disease and peripheral arterial disease. Odds ratios were also adjusted for correlation among multiple within-patient events using the robust Huber-White procedure.

Fistulograms revealed that 45% of patients had percutaneously treatable causes of DASS. Previous studies have reported anywhere from 20%-83% of patients having treatable causes of steal, but only about 33% of those patients underwent fistulograms before surgery. Two patients experienced adverse events that included a left common femoral artery hematoma and chest pain that required a 2-day hospital admission. The DASS interventions in this study demonstrated high rates of technical (94.0%) and clinical (54.2%) success that were consistent with similar modalities performed by vascular surgery. Analysis identified that the intervention group had 60% lower odds of follow up surgery and 70% lower odds of undergoing access revision surgery. Hemodialysis access preservation rate did not differ between the intervention and nonintervention groups, at an encouraging 88.0%.

There are limitations to this study that are due to its design, as a retrospective review it is unable to determine causality. The restriction to a single center also decreases the generalizability of the results to a broader population. There was a lack of complete follow up data due to an absence of standardized follow up intervals. This was mentioned by the authors that the true clinical success rate could be anywhere from 44% to 54% if all patients that were lost to follow up were accounted for.

Commentary

With an increasing prevalence of people receiving hemodialysis access, this study adds a large patient cohort to the Interventional Radiology literature on percutaneous management of DASS. Their analysis, which revealed that percutaneous interventions provided comparable outcomes to surgical interventions while maintaining a minimal side effect profile, was well designed and appropriately accounted for possible confounding variables. The implication was that Interventional Radiology can play a bigger role in the management algorithm of DASS and percutaneous interventions should be considered the first-line treatment for DASS. As the authors correctly noted, further research focusing on establishing causality through randomized control trials and investigating possible unintended consequences of percutaneous venous outflow optimization will elucidate the roles of percutaneous DASS interventions better.

Post Author

Anthony M. Camargo, BA
MD candidate, Class of 2025
University of Massachusetts Chan Medical School
@anthonymcamargo