This release outlines interim results from a small clinical trial proposing a new treatment — geniculate artery embolization (GAE) — to reduce the pain in patients with osteoarthritis (OA) of the knee. The study was presented at the Society of Interventional Radiology’s annual meeting.
The main concerns with this report are the small study size (just 13 patients) and the brief duration of the study. Outcomes include results only through 1 month after the procedure. Almost half of the patients didn’t complete the 1-month follow-up assessment. The study didn’t include a control group. The release also ignored the potential risks of the procedure and its costs.
Knee pain from osteoarthritis is a growing problem among the aging population and new approaches to reduce this type of pain could improve the quality of life for many older patients. Any non-opioid or non-surgical approach which can match the success of knee replacement surgery in resolving pain and improving function would be an advance in caring for people with disabling osteoarthritis of the knee. But this release, and the extremely early stage of this research, goes too far in its claims of benefit. Larger trials of greater duration will be needed before this new invasive approach can be seen as a ready alternative to current treatments.
This release doesn’t mention anything about the cost of this new procedure although interventional radiography procedures are normally complex and expensive. The release is remiss in not pointing out that GAE is likely to be more costly than other standard treatments for knee OA such as corticosteroid injections, exercise regimens and weight loss.
Although the release reports improvement in physical function and decreasing pain based on standard measurements, it’s impossible to use this preliminary report to make any clinical recommendations. Successfully demonstrating the value of this procedure as an effective approach to resolve pain and improve function in an individual with painful OA of the knee will require a longer period of followup and a comparison with control groups including a sham needle insertion group and a group receiving a corticosteroid injection in the knee.
The release doesn’t discuss the potential harms associated with this procedure. The procedure is complex involving the catheterization of “very small arteries or capillaries within the lining of the knee,” and carries inherent risks of penetrating those blood vessels. Potential complications include bleeding at the puncture site and pain. Long-term complications have yet to be determined but could include failure of the intervention to address the symptoms of knee OA, worsening of the pain in some individuals, and osteonecrosis (a bone disease that results from loss of blood supply to the bone). Also yet to be established is the period of time it takes for healing to occur within the joints after the procedure.
According to the release only eight of the 13 participants were assessed at the 1 month follow-up. This represents a loss of more than one-third of the original group of study participants and introduces a potential for significant bias of outcomes in those who completed the study.
The study needs to be followed up with a randomized, long term trial.
The release does point out that a randomized controlled clinical trial that began in February 2018 is intended to provide further data on on the procedure.
The release doesn’t engage in disease mongering.
The release doesn’t note how the study was funded.
The release mentions medications and specifically opioids as one treatment for knee OA. According to the American Academy of Orthopaedic Surgeons, alternatives also include exercise, over-the-counter anti-inflammatory medications such as ibuprofen and naproxen sodium, and corticosteroid injections.
The release is confusing for readers on this point. The release suggests that GAE is an intervention already in current use when it states:
“Interventional radiologists perform GAE for knee pain by inserting catheters through a pinhole-sized incision, blocking the very small arteries or capillaries within the lining of the knee, reducing the inflammation caused by osteoarthritis. As an outpatient treatment, GAE does not require open surgery or physical therapy, and takes 45-90 minutes to perform.”
However, further down in the release its noted that the procedure has “only been used in a clinical trial setting.”
The release doesn’t claim novelty. It states that the research “builds on the growing international research around GAE and osteoarthritis.”
The headline and sub-head (touting “long-term relief”) claim benefits that aren’t supported by the evidence reported on this small, brief study.