Joint Embolization

Background and indications

Joint embolization (or articular neovessel embolization) is a recent technique that extends the principle of genicular artery embolization (GAE) to joints beyond the knee. Pathological synovial neovascularization, associated with chronic inflammation, is a pain mechanism common to osteoarthritis and inflammatory joint conditions.

Joints that can benefit from this technique include the hip, shoulder (adhesive capsulitis or frozen shoulder), elbow, ankle, and wrist. Embolization is offered after failure of conservative treatments (physiotherapy, injections, medical therapy) and can be an alternative to surgery (arthroplasty, arthroscopy).

Pre-procedure assessment

Assessment includes recent imaging (radiographs, MRI with Doppler sequences or post-gadolinium showing synovitis and neovascularization), pain assessment (VAS, specific functional scores), and treatment history.

Procedure

Under local anesthesia, a microcatheter is introduced through the femoral or radial artery. Under fluoroscopic guidance, arteries feeding the inflammatory synovium of the targeted joint are identified and embolized in a super-selective manner with small microspheres (75 µm). The goal is to reduce pathological neovascularization while preserving normal joint vasculature. The procedure takes approximately 45 to 90 minutes.

Results and scientific evidence

For adhesive capsulitis (frozen shoulder), a study of 25 patients showed significant improvement in pain and joint mobility after embolization, with mean VAS score decreasing from 72 to 18 mm at 6 months (Okuno et al., Journal of Vascular and Interventional Radiology, 2017; DOI: 10.1016/j.jvir.2017.02.038). For hip osteoarthritis, initial series show promising results with a 60-75% response rate.

Risks and complications

Complications are similar to GAE: transient skin discoloration (5-10%), transient local pain (< 5%). Major complications are exceptional with super-selective catheterization and small microspheres.

Recovery

Return to activities is possible the following day. Improvement is progressive over 2 to 8 weeks. Rehabilitation is encouraged in parallel. Follow-up at 1, 3, and 6 months.

Practical information

The procedure is performed as an outpatient or short inpatient stay depending on the case. It is performed by a specialized interventional radiologist.