Yan Epelboym

Knee osteoarthritis (KOA) is a serious disease and a leading cause of disability. Genicular artery embolization (GAE) is emerging as a minimally invasive option for refractory pain treatment; determining the optimal patient profile for this intervention continues to be a primary focus of current clinical trials. Current patient selection often relies on self-reported symptom scores and radiographs, which fail to capture the biological heterogeneity of KOA. The purpose of this review is to summarize imaging and biochemical markers that may optimize patient selection and predict outcomes for GAE. Magnetic resonance imaging-based biomarkers enable detailed assessment of bone marrow lesions and inflammatory burden. Phenotypes characterized by mild-to-moderate synovitis are associated with improved response to GAE. Biochemical markers such as CTX-II and hyaluronic acid reflect overall disease activity in osteoarthritis, while inflammatory mediators and angiogenic factors are linked to synovial inflammation and pain mechanisms. Post-GAE reductions in circulating vascular endothelial growth factor and interleukin-1 receptor antagonist were observed alongside sustained pain relief, suggesting that angiogenic and inflammatory processes may contribute to symptom improvement after embolization, although this evidence is currently limited and requires further validation. Integrating imaging phenotypes with molecular endotypes can offer a more precise framework for selecting GAE candidates and predicting outcomes.

Adhesive capsulitis (AC) is a common cause of chronic shoulder pain for which transcatheter arterial embolization (TAE) is emerging as a minimally invasive therapy. This intervention targets neovascularization associated with chronic inflammation in AC. This review aims to summarize the vascular anatomy of the shoulder relevant to embolization. We report on data from cadaveric, diagnostic imaging, and embolization studies evaluating axillary artery branches, their variants, and angiographic blush patterns in AC embolization. The shoulder's arterial supply arises primarily from the axillary artery and thyrocervical trunk, which form extensive anastomoses. Angiographic studies of patients undergoing TAE demonstrate a hyper vascular blush in symptomatic regions and include characterization of the arterial branches perfusing these regions. Detailed knowledge of the vascular anatomy of the shoulder and its variants is valuable to understand, so as to perform TAE in a safe and effective manner.

Knee osteoarthritis (OA) is a major cause of pain and disability. Genicular artery embolization (GAE) is a promising alternative for patients unresponsive to conservative treatment or unsuitable for total knee replacement. GAE may alleviate knee pain by reducing synovitis and by causing ischemia to pathologic knee nerves. However, outcomes vary based on baseline MRI and radiographic findings, making patient selection challenging. Recently, reduction in synovitis on contrast-enhanced MRI has been associated with pain relief post-GAE. Novel OA phenotypes (inflammatory, cartilage, bone, and atrophic) can aid in patient selection by using imaging and molecular biomarkers. Moreover, imaging features such as cartilage defects, bone marrow lesions, and synovitis may predict symptomatic outcomes. This review explores OA pathophysiology, focusing on radiographic, biochemical, and imaging biomarkers in evaluating GAE for knee OA treatment.