01 · Seed
NanoATi · Evidence by component
What supports each part of NanoATi?
NanoATi can begin with a tendon-derived tenocyte Seed or an accessible hair-derived fibroblast-rich Seed, then adds collagen support and an autologous signal. Human component evidence and the remaining gaps are labelled precisely.
Reviewed byProfessor Paul Lee MBBch, FRCS (Tr & Orth), PhDCartilage and joint preservation expertiseQuick answer
There is no direct human trial of the complete NanoATi protocol. Human autologous-tenocyte studies support the tendon-derived cell concept, while human hair-follicle research supports an alternative donor niche; neither proves the same-day Seed. Collagen and platelet-rich-fibrin evidence remains related, mixed and partly indirect.
Verified across three networks
Trusted by patients on Doctify, Google and Top Doctors
A transparent evidence map
Three components. Three evidence questions.
Each part is assessed against the tendon target. Evidence for one component is never presented as proof of the complete protocol.
02 · Soil
Type-I collagen scaffold
03 · Signal
Platelet-rich fibrin
01 · Seed
Autologous tenocyte or fibroblast-rich micrografts
Professor Lee can select a small direct tendon sample to retain tissue-specific tenocytes, or a hair-follicle-bearing dermal sample as an accessible fibroblast-rich source. The tissue is mechanically processed on the day rather than culture-expanded.
How directly does the evidence apply?
Human autologous-tenocyte studies establish that tendon-derived cells can be harvested and delivered to resistant human tendinopathy, including a reported partial-thickness rotator-cuff case. Human hair-follicle research establishes an accessible multipotent dermal cell niche. Neither route has been tested as Professor Lee’s same-day mechanically processed NanoATi Seed.
Target-tissue evidenceHuman pilot clinical study involving 20 patients with chronic lateral epicondylitis.
Autologous tenocytes for resistant human tendinopathy
Wang A et al. American Journal of Sports Medicine. 2013;41(12):2925–2932.
Tenocytes expanded from a small patellar-tendon biopsy were delivered under ultrasound guidance; the study reported improved pain, function, grip strength and MRI appearance at 12 months.
Why it belongs here: Direct human evidence for autologous tendon-cell harvest and injection, but it used culture-expanded tenocytes, a different tendon and not the same-day combined NanoATi protocol.
Read the published sourceTarget-tissue evidenceHuman clinical case report in an elite gymnast.
Autologous tenocytes in a partial rotator-cuff tear
Wang A et al. BMJ Case Reports. 2013;2013:bcr2012007899.
A partial-thickness rotator-cuff tear was treated with ultrasound-guided autologous tenocyte implantation; symptoms and MRI appearance improved and the athlete returned to national competition.
Why it belongs here: Shoulder-specific human experience with tendon-derived cells, but a single case using culture expansion—not evidence for the complete NanoATi technique.
Read the published sourceMechanistic evidenceHuman hair-follicle cell isolation and laboratory differentiation study.
Multipotent cells from human hair follicles
Bajpai VK et al. Stem Cell Research. 2012;8(1):74–84.
Human hair-follicle-derived mesenchymal cells were highly proliferative and most clones demonstrated differentiation across two or three tested lineages.
Why it belongs here: Human donor-niche evidence for the hair-derived option, but not tenocyte differentiation, same-day micrografts or a tendon treatment outcome.
Read the published source02 · Soil
Injectable type-I collagen scaffold
A three-dimensional type-I collagen framework used to support local retention and organisation around the delivered micrografts.
How directly does the evidence apply?
Tendon is predominantly type-I collagen. A small human pilot combined tendon-derived cells with a different type-I collagen scaffold during rotator cuff repair. Professor Lee currently selects ChondroFiller as the injectable Soil, but its published product evidence is in cartilage, not tendon.
Indirect evidenceSmall clinical pilot involving 18 surgical patients.
Tendon-derived cells with a type-I collagen scaffold in rotator cuff repair
Human pilot study. 2022. PMID: 34976729.
The study explored tendon-derived cells carried on a type-I collagen scaffold during rotator cuff repair.
Why it belongs here: Biologically relevant but indirect: a different scaffold, a surgical procedure and a different cell-processing pathway.
Read the published source03 · Signal
Autologous platelet-rich fibrin
An autologous fibrin and platelet preparation used to provide a local matrix and platelet-derived biological signals.
How directly does the evidence apply?
The Vivostat PRF system selected by Professor Lee has been tested in tendon surgery, but the randomised rotator-cuff pilot did not show improvement. This exact-platform evidence is important precisely because it is not positive, and it cannot support a promise for NanoATi.
Mixed evidenceRandomised pilot study involving 28 patients.
Vivostat PRF during massive rotator cuff repair
Antuña S et al. Acta Orthopaedica Belgica. 2013;79(1):25–30.
The study did not show better clinical or structural outcomes with PRF; retears occurred in both groups.
Why it belongs here: Exact-platform tendon evidence, but as an adjunct to surgery rather than non-operative NanoATi—and the result was negative.
Read the paper (PDF)Mixed evidenceRandomised controlled trial involving 79 patients.
Platelet-rich fibrin matrix in rotator cuff repair
Rodeo SA et al. American Journal of Sports Medicine. 2012;40(6):1234–1241.
The platelet-rich fibrin matrix did not improve tendon-to-bone healing or clinical outcomes.
Why it belongs here: Relevant caution from another PRF preparation; it does not directly test ArthroZheal or NanoATi.
Read the published sourceThe combined protocol
Clinical innovation, with the evidence boundary kept visible
NanoATi is Professor Lee’s clinician-developed technique for combining tendon- or hair-derived autologous micrografts, collagen support and an autologous signal. In its standard form it is delivered percutaneously without an operation. The protocol should be evaluated through its own prospectively recorded outcomes rather than borrowing certainty from adjacent studies.
Progress sometimes begins by bringing established biological principles together before the combination has a mature evidence base of its own. Years of research, operating experience and familiarity with the component parts provide a serious basis for innovation. They are also the reason to state the remaining uncertainty precisely, rather than hide it behind a broad claim.
Questions about the NanoATi evidence
Is there direct human evidence for the NanoATi Seed?
Human studies have harvested and injected culture-expanded autologous tenocytes, including a reported partial rotator-cuff tear, and human laboratory work supports the multipotency of hair-follicle-derived cells. Neither donor route has been tested as Professor Lee’s same-day mechanically processed NanoATi Seed.
Why use a type-I collagen scaffold in tendon?
The rationale is that tendon is predominantly type-I collagen and ChondroFiller provides an injectable type-I collagen framework. That is an extrapolation from biology and from other scaffold research: ChondroFiller’s published clinical product evidence is in cartilage, not tendon.
What does the ArthroZheal tendon evidence show?
The exact Vivostat PRF platform has been assessed during rotator cuff surgery, but a small randomised pilot did not demonstrate improved outcomes. That negative result is shown because a balanced evidence page must include evidence that does not support benefit.
Does the biological injection replace tendon rehabilitation?
No. Progressive mechanical loading remains central to tendon recovery. The loading plan is part of the pathway and the clinical outcome should be judged by strength, function and task tolerance as well as symptoms.
Still have more specific concerns?
Free Discovery CallOptions that our doctors may discuss include NanoACi, ChondroFiller, Mytocel MSK, joint replacement, established conservative care or surgery, depending on examination and imaging.
Discuss the evidence, limitations and alternatives
Professor Lee can explain how the evidence applies to your tendon, where the rationale is extrapolated and whether this pathway is proportionate.