ORTHOBIOLOGIC DIGEST™
Updated: 6 days ago
ORTHOBIOLOGIC DIGEST™
September 14, 2026
Research. Evidence. Perspective.
Curated by Deborah Westergaard, MD
Orthobiologic medicine is moving quickly. Every week, new studies, media stories and social-media claims appear about PRP, bone marrow concentrate, stem cells, joint preservation and regenerative medicine.
Some are genuinely exciting. Some raise more questions than they answer. And sometimes an interesting piece of science becomes a much bigger claim by the time it reaches social media.
In the Orthobiologic Digest™, I select research and stories that I think matter, explain what they actually show in plain language, and then give you my perspective as a physician whose practice has evolved from decades of interventional spine and joint care to a current focus on orthobiologic treatments, joint preservation and helping patients avoid surgery when appropriate.
This week, we're looking at five stories.
1. Can We Really Regenerate a Degenerated Spinal Disc?
The science behind a viral image
A dramatic illustration has been circulating on social media showing a severely collapsed cervical disc returning almost to normal after an injection of “hydrogel & cells.”
The science behind disc regeneration is real and genuinely exciting. But the illustration communicates considerably more than current human evidence has demonstrated.
Mayo Clinic researchers are studying cells combined with injectable hydrogels for degenerative disc disease. Another study by Cherif and colleagues tested an injectable material called NPgel, alone and with bone-marrow progenitor cells, in naturally degenerated human discs.
Researchers reported encouraging improvements in disc height, MRI signal, mechanical properties and biological activity.
But there is a critical distinction:
These were human discs, not humans being treated.
The discs had been removed from the body and studied in a mechanically loaded laboratory system. There were no patients demonstrating relief of cervical radiculopathy, reversal of foraminal stenosis or avoidance of cervical fusion.
Dr. Westergaard's Perspective
A more hydrated disc is not necessarily a restored spine. I am genuinely excited about this research. But disc degeneration develops over years, and the entire functional spinal unit changes with it. As disc height decreases, the facets remodel, osteophytes can develop, endplates change, the annulus deteriorates and the neural foramina may narrow. A disc also isn't an inner tube that simply needs to be reinflated. Normal nucleus pressure depends upon a mechanically competent annulus and endplate system. I find this technology particularly interesting as a potential earlier-stage intervention, before severe structural remodeling has occurred. Demonstrating improved hydration or disc height in experimental tissue, however, is very different from demonstrating that we can restore a severely degenerated spinal segment in a living patient. We should continue the research without allowing the promise to outrun the evidence.
2. Treating More Than the Disc: BMAC for Degenerative Discs and Vertebral Endplates
Study: Combined Subchondral, Intradiscal and Peridiscal BMAC Injections for Advanced Degenerative Discs and Endplates with Modic Changes: Retrospective Pilot Case Series
Source: Pain Medicine Case Reports, 2026
What the Study Found
This pilot study looked at 13 patients with chronic low-back pain, degenerative disc disease and Modic changes, which are MRI changes involving the vertebral endplates and adjacent bone.
Rather than treating the degenerative disc alone, investigators used bone marrow aspirate concentrate, or BMAC, in several components of the degenerative spinal segment. BMAC was placed into the disc, into the adjacent subchondral vertebral/endplate region, and around the disc.
Average pain decreased from 7.3 out of 10 to 2.1, an improvement of approximately 73%. All 13 patients achieved at least 50% pain reduction, and 12 of 13 reported being satisfied or very satisfied. Follow-up ranged from four to 15 months, with no major procedure-related complications reported.
It is a small retrospective case series, so larger controlled studies are needed. What makes it particularly interesting to me is the concept of treating the disc and the diseased bone immediately adjacent to it together.
Dr. Westergaard's Perspective
I've been waiting for a study like this. What interests me most isn't simply the approximately 73% reduction in pain. Thirteen patients is a small study, and I look forward to larger prospective randomized controlled trials. What excites me is where the investigators treated. They didn't approach degenerative disc disease as though the disc exists by itself. They treated both the disc and the adjacent vertebral/subchondral bone. Conceptually, this reminds me of the work of Dr. Philippe Hernigou in knee osteoarthritis. His long-term research has examined treating diseased subchondral bone beneath an arthritic knee rather than focusing exclusively on the inside of the joint. While attending an IOF meeting in 2025, I had an opportunity during a break to introduce myself to Dr. Hernigou and briefly discuss his research. The possibility of applying a similar subchondral concept to the spine came up. I remember walking away thinking, this makes biological sense. I wish we had the clinical studies to support doing it. That's why I was particularly interested to see this paper. I think the concept could ultimately go further. Degenerative disc disease occurs within a functional spinal unit. The facet joints, supporting ligaments and paraspinal musculature may also contribute to pain and abnormal mechanics. I would be very interested in future controlled studies examining a comprehensive approach addressing the disc, vertebral/subchondral bone and, when clinically appropriate, the posterior elements of the functional spinal unit. This research moves in a direction I have been hoping to see: away from treating the disc in isolation and toward treating the degenerative spinal segment as an interconnected biological and mechanical system.
Read the original study:
3. Treating the Bone Beneath the Joint: Long-Term BMC Outcomes in Ankle Osteoarthritis
Study: Intraosseous Bone Marrow Concentrate and Long-Term Procedure-Free Survival in Bilateral Non-Traumatic Ankle Osteoarthritis: A Contralateral-Controlled Study
Authors: Philippe Hernigou, Christopher J. Centeno, Dustin R. Berger, Ehren Dodson and Matthew B. Murphy
Source: Medicina, 2026
What the Study Found
This study examined patients with osteoarthritis in both ankles, creating an interesting opportunity to compare outcomes within the same individual.
One ankle received intraosseous bone marrow concentrate, targeting the subchondral bone beneath the joint surface, while the contralateral ankle provided a comparison.
The contralateral design is particularly interesting because each patient provides his or her own comparison, helping reduce some of the variability encountered when entirely different groups of patients are compared.
Most importantly, the investigators looked at long-term procedure-free survival, not simply whether pain improved for several months.
The BMC-treated ankles demonstrated substantially better long-term procedure-free survival.
That gets much closer to the question patients interested in joint preservation actually ask:
Can I preserve my own joint and delay or avoid more invasive procedures?
Dr. Westergaard's Perspective
I think subchondral bone treatment is becoming an important part of the evolution of joint preservation. What I particularly like about this study is the outcome the investigators chose. They weren't simply asking whether patients reported less pain several months after an injection. They looked at long-term procedure-free survival. To me, that is a much more meaningful joint-preservation endpoint. Patients want to know whether they can remain active, preserve their own joint and potentially delay or avoid more invasive procedures. I think we're seeing an important trend in orthobiologics: moving beyond treating only the inside of the joint and recognizing the importance of the subchondral bone supporting the joint surface. We have seen this concept developed through Dr. Philippe Hernigou's work in knee osteoarthritis. Now we're seeing it examined in the ankle, and earlier in this issue we discussed research applying a related concept to the vertebral endplates in degenerative spine disease. Cartilage, subchondral bone and the surrounding mechanical structures don't function independently. If our objective is truly joint preservation rather than temporary symptom control, we may need to treat the joint as an interconnected biological and mechanical system. I have tremendous respect for the work of Dr. Philippe Hernigou, Dr. Christopher Centeno and Matthew Murphy in advancing this area of research. Through my affiliation and training with Regenexx, I am fortunate to have access to treatment protocols informed by this body of work, and that knowledge helps inform the joint-preservation strategies available to my patients. I think this study adds important long-term evidence supporting the concept that subchondral bone is a therapeutic target in osteoarthritis and reinforces the direction in which joint-preservation medicine is evolving.
Read the full study: Medicina — Intraosseous Bone Marrow Concentrate and Long-Term Procedure-Free Survival in Ankle Osteoarthritis
4. “100 Million Stem Cells” for Knee Arthritis: Does More Mean Better?
Source: Cell Grand Clinic, Osaka, Japan
What the Article Describes
A Japanese clinic is marketing a knee-osteoarthritis treatment involving approximately 100 million culture-expanded cells.
The clinic describes obtaining a small amount of the patient's adipose tissue, isolating adipose-derived mesenchymal stromal/stem cells and then culture-expanding them outside the body for approximately seven weeks before injecting them into the knee.
There is legitimate research investigating culture-expanded adipose-derived cells for knee osteoarthritis.
But “100 million” is a cell dose, not an outcome.
More cells don't automatically mean greater clinical benefit. Cell viability, phenotype, culture conditions and biological activity matter in addition to raw cell count.
The regulatory environment is also different. A culture-expanded cellular product such as this would generally require an FDA-regulated drug/biologic development pathway in the United States rather than being offered as a routine same-day orthobiologic procedure.
Dr. Westergaard's Perspective
I find the science of culture-expanded adipose-derived cells interesting, but for me the more important question is what structures are actually being treated. This appears to be an intra-articular treatment. The cells may influence cartilage and the synovial environment, but that isn't the same as addressing the entire degenerative joint. Cartilage doesn't function by itself. It interacts with synovial fluid and the subchondral bone beneath it, while the entire joint depends upon bone, menisci, ligaments, tendons and muscles for normal mechanics. We have substantial long-term research supporting the importance of the subchondral compartment in joint preservation, particularly with bone-marrow-based approaches. I don't believe we yet have comparable long-term evidence for injecting culture-expanded adipose-derived cells into subchondral bone, and I would not assume that simply increasing the number of cultured cells solves that problem. For an American patient considering traveling internationally for a “100 million stem cell” knee injection, I would first ask: Have we adequately evaluated the entire knee and identified all of the structures contributing to its degeneration? Evidencei nformed autologous orthobiologic options are already available in the United States when appropriately indicated. My priority would be choosing the right biological treatment for the right tissue rather than choosing treatment based primarily on the largest cell number being advertised. The goal isn't to inject the biggest number of cells. It's to identify what's wrong with the knee and treat the appropriate targets.
Read the original article: Cell Grand Clinic — Knee Regenerative Medicine Alternatives
5. An NFL Player Tried PRP and Still Needed Surgery. Did PRP Fail?
Source: NBC Sports / ProFootballTalkPatient: Indianapolis Colts wide receiver Alec Pierce
What Happened
Alec Pierce dealt with a persistent left ankle problem during the 2025 NFL season.
After the season, he received a PRP injection in January 2026, reportedly in hopes of resolving the persistent problem and avoiding surgery.
Ultimately, Pierce underwent ankle surgery in March.
At first glance, the story seems straightforward:
PRP didn't work, so the athlete needed surgery.
But the public reporting leaves out almost everything we would need to evaluate that conclusion medically.
The reports don't tell us Pierce's precise diagnosis. We don't know which structure was injected, what PRP formulation was used, whether the procedure was image-guided, or what pathology ultimately required surgery.
A subsequent report that Pierce received a second PRP injection was corrected by the Colts. According to the team's general manager, Pierce received only the original January injection.
So what does this episode actually establish?
PRP did not eliminate Pierce's eventual need for ankle surgery.
It does not tell us why.
Dr. Westergaard's Perspective
The way a story like this can be interpreted publicly is simply: “PRP didn't work. But medically, we aren't given enough information to reach that conclusion.We don't know the diagnosis. We don't know what structure was treated. We don't know what PRP preparation was used, where it was placed or whether the injection was image-guided. We also don't know what pathology ultimately led to surgery. There is even the possibility that a different orthobiologic strategy, potentially including bone marrow concentrate for an appropriate osseous or subchondral lesion, might have been considered. But we simply don't have enough clinical information to know whether that would have been appropriate in this particular case. Sometimes surgery is the right treatment. Sometimes an orthobiologic treatment is appropriate. And sometimes a treatment may help without eliminating the eventual need for surgery. The fact that an athlete received PRP and later underwent surgery does not, by itself, tell us whether PRP works or doesn't work. It tells us why diagnosis, patient selection, biologic formulation and accurate treatment targeting matter.
Read the original coverage:
This Week's Takeaway
These five stories may seem very different, but I see a common thread running through all of them:
The details matter.
A more hydrated disc is not necessarily a restored spine.
Treating a degenerative disc without considering the adjacent vertebral bone may overlook an important part of the disease.
A higher platelet concentration doesn't automatically guarantee a better tendon outcome.
Cartilage cannot be considered independently of the bone supporting it.
One hundred million cells is a dose, not proof of a better result.
And the fact that an athlete received PRP and later underwent surgery tells us almost nothing unless we understand the pathology, treatment and therapeutic goal.
Orthobiologics is moving beyond the idea of simply injecting something into the place that hurts.
The more interesting question is increasingly:
What structures are contributing to the disease, what biology is occurring in those tissues, and how can we treat the entire functional unit while preserving as much normal anatomy as possible?
That is where I believe joint and spine preservation is heading.
And that is what I will continue watching as the evidence develops.
Deborah Westergaard, MD Orthobiologic Digest™
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