Micro-embolisation to improve pain & function in early stage knee osteoarthritis24 month pilot study results

Steve Landers1, Rachael Hely1, Richard Page2,3, Andrew Hely1. Benjamin Harrison1, Nicholas Maister1, Stephen Gill1,2,3

1Barwon Medical Imaging, Barwon Health; 2Barwon Centre for Orthopaedic Research & Education (B-CORE); 3Deakin University, School of Medicine

BACKGROUNDSymptomatic knee osteoarthritis (OA) is a common and disablingdisease. OA has no known cure and treatment is directed towardsmodifying symptoms. In late stage OA, symptoms can be successfullytreated with arthroplasty, but early stage OA management can bechallenging.

OA is accompanied by angiogenesis, which is blood vessel outgrowthfrom pre-existing vasculature (Figure 1A).

Blocking the flow of blood in these neovessels via micro-embolization is an emerging treatment option for OA. One single-arm study has previously demonstrated large improvements in painand function in participants following micro-embolisation.

AIMS1. Investigate the safety and feasibility of micro-embolisation in

people with mild knee OA2. Investigate effects of micro-embolisation on pain, function and

quality of life at 1, 6, 12 & 24 months

METHODSStudy Design: single-arm prospective pilot studyStudy site: Barwon HealthParticipants: 10 people with symptomatic early stage knee OA whohad failed traditional conservative managementIntervention: transcatheter arterial embolisation in the angiographysuite at Barwon Medical Imaging (see Image). A microcatheter wasinserted into the femoral artery at the groin and passed to the knee.Iodinated contrast agent was inserted to reveal neovasculature onangiogram. Embolic particles were inserted to block neovessels andreturn vasculature to its normal state. The procedure took 60-120minutes. Participants were discharged home after 4 hours ofobservation.Primary outcome: proportion of ‘responders’ at 12 months. Aresponder fulfils at least two criteria:1. Pain improved >20% from baseline and absolute change >10 points

on a 0-100 interval scale2. Function improved >20% from baseline and absolute change >10

points on a 0-100 interval scale3. Patient’s global assessment of ‘moderately better’ or ‘much better’

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RESULTSTechnical success: neovessels were identified and embolised in all participantsSafety: no adverse events occurred. No osteonecrosis (bone death) was observed on 24 month MRI.Follow up: 10 participants to 12 months; 8 participants to 24 months

CONCLUSIONSPost-procedural improvements provide evidence that micro-embolisation might be an effective symptomatictreatment technique for people with early stage knee osteoarthritis. Evaluating the procedure with moreadvanced study designs is warranted to produce higher quality evidence regarding this novel procedure; arandomised, placebo-controlled, assessor and participant blinded study is now underway (a world-first).

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Physical Performance

Chair stand testSix minute walk test