Novel transcatheter arterial embolization for treatment of knee osteoarthritis: a randomized sham-controlled clinical trial

Osteoarthritis (OA) is the most common joint disease resulting in severe
morbidity and, of all joint diseases, incurs the most years lived with
disability and highest costs on a population level.
There are no definite or disease-modifying treatment options for OA: current
therapies are purely symptomatic, temporary and oftentimes ineffective, or
entail major joint replacement surgery in end-stage OA.
Joint replacement, however, has limited durability, carries risks of
complications, and can be impossible in case of comorbidities. The most
frequently affected joint by OA is the knee. It is critical to identify novel
therapies to decrease the significant morbidity of knee OA, while delaying the
time to joint replacement for as long as possible, because survival rates of
knee prosthesis are higher when performed at older age.

An increasing body of literature suggests that periarticular soft tissues, such
as synovium, fat pad, and joint capsule that are affected by inflammatory
processes, are likely sources of pain in knee OA.

Since pain is the predominant symptom of OA, there is a need for novel
therapies for knee OA that reduce pain by targeting the inflammation of
periarticular soft tissues.

The main objective is to assess whether transcatheter arterial embolization of
neovessels in patients with symptomatic knee OA results in significant pain
reduction after 4 months compared to sham treatment.

We hypothesize that novel transcatheter arterial embolization of neovessels is
a feasible, effective, and safe treatment for patients with symptomatic
radiographic knee OA, resulting in significant improvement of pain symptoms in
a period of 4 months follow-up compared to placebo.

Secondary objectives are:
1) to assess whether reduction of neovessels is related to pain relief,
2) to explore whether decrease of inflammation is a mediating factor between
neovessel reduction and pain relief,
3) to assess whether transcatheter arterial embolization reduction of
neovessels decreases peripheral and central pain
sensitization and
4) to assess whether transcatheter arterial embolization improve the outcome
at 1, 4, 8 and 12 months compared to placebo
of the: ICOAP, painDETECT, EQ-5D-5L and NRS questionnaires.

Double-blinded randomized placebo-controlled clinical trial

One group (n=29) undergoes transcatheter arterial embolization of neovessels
around the knee and the other group (n=29) undergoes placebo- embolization.

Participants of this study will undergo a blood test for determining the kidney
function, 5 questionnaires (Knee injury and Osteoarthritis Outcome Score,
Measure of Intermittent and Constant Osteoarthritis Pain, painDETECT, Numeric
rating scale (for pain severity, stiffness, and swollenness in the knee) and
the EQ-5D-5L questionnaire ) will be filled in at 5 different time points.

Pain pressure threshold testing using an algometer will be performed at the
same 5 time points.

MRI of the knee with a contrast agent and a duration of approximately 45
minutes will be performed at baseline, 1 and 4 months follow-up.

These measurements will result in five additional hospital visits. All travel
expenses made due to these visits will be reimbursed.

The intervention arm undergoes Digital Subtraction Angiography (DSA) during the
intervention.
Therefore, this study arm is at risk for infections of site access,
subcutaneous haemorrhage and dissection of the femoral artery.

The radiation exposure is expected to be around 4 mSv.

Only the intervention group will undergo embolization of neovessels. A
potential risk of embolization is non-target embolization.