APEX Webinar Recap Featuring Dr. Walter Sussman l April 2026
Osteoarthritis (OA) has long been viewed as a cartilage problem. But what if we’ve been focusing on only half the picture?
In a recent APEX educational webinar, Dr. Walter Sussman, board-certified PM&R and Sports Medicine specialist, explored one of the most exciting shifts in regenerative medicine today - treating the osteochondral unit, including subchondral bone, through intraosseous delivery of autologous biologic therapies.
The result? A fresh framework for understanding joint pain, patient selection, and long-term outcomes in OA care.
Traditional OA treatment often centers on cartilage loss, narrowing joint space, and symptom management with injections or medication.
But Dr. Sussman emphasized that subchondral bone plays a critical role in:
MRI imaging frequently reveals bone marrow lesions (BMLs) even when X-rays appear relatively normal.
“If we’re not looking for these lesions, we may be missing half the picture.” - Dr. Walter Sussman
Dr. Sussman shared a highly practical clinical framework:
Symptoms:
Often responds well to:
Symptoms:
These patients often experience limited improvement with traditional intra-articular injections and may be stronger candidates for intraosseous biologic treatment targeting the subchondral bone.
BMLs are more than imaging findings, they may be powerful predictors of disease progression.
Dr. Sussman reviewed studies showing:
Larger BMLs correlate with painful knees
Presence of BMLs increases likelihood of OA progression
Extensive lesions may predict progression to total knee arthroplasty
One study cited showed patients with larger lesions were up to 13x more likely to require knee replacement.
This was one of the most compelling parts of the webinar.
Studies comparing intra-articular vs intraosseous biologic injections demonstrated:
Patients receiving combined intra-articular + intraosseous PRP demonstrated greater pain reduction than joint injections alone.
BMAC delivered intraosseously showed improved functional outcomes over intra-articular treatment.
Some patients demonstrated:
Perhaps most impressive: 82% of patients receiving intraosseous BMAC avoided total knee replacement at 15 years.
Dr. Sussman addressed a common question: should clinicians recommend PRP or BMAC?
His perspective:
Another valuable takeaway: consider OA as a whole-joint disease.
When meniscal pathology coexists with BMLs, combining:
may provide stronger outcomes than isolated treatment alone.
By understanding the role of the osteochondral unit and targeting the pain-generating subchondral bone, clinicians may unlock new options for patients who have historically had few.
“There are breadcrumbs in the literature showing us how we should be practicing.” - Dr. Walter Sussman
Watch the on-demand replay of the APEX Webinar featuring Dr. Walter Sussman to learn how intraosseous biologic therapies are reshaping osteoarthritis care and patient outcomes.
You can also explore the APEX Resource Library for additional clinical education, webinar replays, treatment insights, and regenerative medicine resources designed to support providers in advancing patient care.
Clinicians interested in advancing their regenerative medicine skills can participate in immersive training programs at the XCELL Learning Center in Clearwater, Florida.
Programs include:
Hands-on procedural training
Cadaver-based workshops
Faculty-led education from leaders in orthobiologics
Explore upcoming training opportunities designed to support responsible adoption of regenerative medicine, visit: xclearningcenter.com
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Hernigou, P., et al. Subchondral bone or intra-articular injection of bone marrow concentrate mesenchymal stem cells in bilateral knee osteoarthritis: what better postpone knee arthroplasty at fifteen years? A randomized study. Int Orthop. 2021;45(2):391-399. doi: 10.1007/s00264-020-04687-7
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