Woman gardening comfortably with her granddaughter

Cartilage regeneration · Professor Lee technique

The cartilage operationtaken out of the operation.

NANO ACi is Professor Paul Lee’s one-stage cartilage regeneration technique: the patient’s own cartilage micrografts as the seed, ChondroFiller collagen as the soil and platelet-rich fibrin as the signal, prepared and delivered through one needle with image-guided precision.

One planned sessionNo laboratory cell cultureNeedle-deliveredSeed · Soil · Signal
Discuss your caseExplore the cartilage hub

Clinical plate 01 · Cartilage surface and joint load

Cartilage damage changes how a joint surface carries load

Articular cartilage creates a smooth, low-friction surface and spreads load into the bone beneath it. Damage can appear as softening, roughening, thinning, local injury or more established osteoarthritic wear.

Three anatomical knee illustrations showing healthy articular cartilage, early-to-moderate thinning and fibrillation, and advanced diffuse cartilage wear with narrowing of the joint space
Healthy surfaceThinning and rougheningAdvanced wear

Mechanical question

Map the pattern of cartilage loss while assessing alignment, stability, meniscus and subchondral load.

Regenerative opportunity

Create and retain a cartilage-specific repair environment at the clinically defined joint surface.

01Define the tissue before the technique

What happens in the session

One pathway, coordinated around the patient

NANO ACi is designed as one point-of-care pathway. The sequence matters: establish that cartilage is the correct target, prepare each biological role, deliver accurately and protect the new environment while the joint adapts.

Medical illustration of the NANO ACi pathway from clinical and MRI assessment through tissue harvest and point-of-care micrograft preparation to biological combination, image-guided knee delivery and protected recovery
The pathway is planned around the pattern of cartilage damage; the illustration shows the clinical sequence, while the stage notes below explain each decision.

  1. Stage 01

    Select target tissue

    Map the joint

    Examination and imaging define whether pain is being driven by cartilage, bone, alignment, instability, meniscus or inflammation—and whether regeneration is a credible option at all.

  2. Stage 02

    Harvest seed

    Autologous tissue source

    Autologous auricular-cartilage micrografts prepared through Mytocel MSK provide the chondrogenic starting material.

  3. Stage 03

    Prepare soil

    Build the local environment

    ChondroFiller native Type I collagen provides the three-dimensional soil at the cartilage target.

  4. Stage 04

    Add signal

    Supply the biological instruction

    ArthroZheal platelet-rich fibrin provides the patient-derived biological signal.

  5. Stage 05

    Deliver precisely

    Deliver and protect the target

    The complete preparation is delivered under image guidance, then protected through a recovery plan matched to the joint and its pattern of cartilage damage.

  6. Stage 06

    Protect and measure recovery

    Let cartilage biology meet the mechanical plan

    Professor Lee describes the treatment session as approximately 30 minutes; the assessment, preparation and recovery plan extend beyond that treatment-room time.

The biological integration

Seed · Soil · Signal

The organising logic stays constant. The clinical meaning changes with the source tissue, target anatomy and mechanics of repair.

Detailed medical cutaway of cartilage and subchondral bone showing a locally retained repair environment with magnified cellular seed, supporting matrix soil and molecular signal

Seed

Autologous auricular-cartilage micrografts prepared through Mytocel MSK provide the chondrogenic starting material.

Soil

ChondroFiller native Type I collagen provides the three-dimensional soil at the cartilage target.

Signal

ArthroZheal platelet-rich fibrin provides the patient-derived biological signal.

Same method · different target

Medical illustration atlas comparing the distinct anatomy and damage patterns of articular cartilage, tendon, meniscus and bone

NANO ACi

Cartilage

Cartilage wear or damage

NANO ATi

Tendon

Disrupted collagen fibres

NANO AMi

Meniscus

Load-sharing tear

NANO AOi

Bone

Trabecular defect

The idea behind NANO ACi

Paul did not invent another box. He redesigned the operation.

In his book Regeneration Made Simple, Professor Lee describes the moment that changed his approach: standing in theatre while a liquid collagen scaffold set inside a joint. The material needed time and an accurate target. It did not need a general anaesthetic, an incision or a theatre team simply because that was how the operation had always been organised.

He applied the same question to every stage. Could cells be prepared at the point of care instead of grown in a laboratory? Could the patient’s own blood provide the physiological medium? Could the three parts be delivered together in one sitting? NANO ACi is the surgical answer to those questions.

“The innovation is not something I added. The innovation is the surgery I took away.”

Movement is the meaningful outcome

Cartilage matters when the knee has to bend and take weight

A cartilage plan is not judged by an impressive treatment name. It is judged by whether the joint can become quieter, more reliable and more useful through the bending and loading that ordinary life requires.

Woman bending comfortably to tie a walking shoe before a park walk
NANO ACi is considered within a joint-preservation plan; no single image represents or guarantees an individual result.

Where it may fit

A joint still worth saving

NANO ACi is designed for the difficult space between symptom management and joint replacement. Assessment considers the pattern of cartilage loss, bone, alignment, stability, meniscus, inflammation, age, activity and the patient’s goals.

  • • A cartilage problem that is meaningful enough to treat.
  • • A joint whose mechanics and biology can still support preservation.
  • • A patient who understands that recovery and outcome remain individual.

Where it may not fit

When another answer is more honest

A regenerative label does not make every painful joint suitable. Uncorrected instability, severe malalignment, infection, uncontrolled inflammation or a joint already beyond meaningful preservation may require a different operation—or joint replacement.

Professor Lee’s PRRR framework considers Preserve, Repair, Regenerate and Replace as choices in sequence, not as competing ideologies.

Evidence, stated plainly

Evidence for the parts is not automatically evidence for the whole

Autologous micrografting, collagen scaffolds and platelet-rich fibrin each have a clinical and scientific literature. NANO ACi combines those roles in a newer, surgeon-designed protocol. Professor Lee’s NANO ACi 100 programme follows the first 100 patients prospectively so the complete technique is judged by its own outcomes.

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FAQ

Questions about NANO ACi

The short answers patients usually need before deciding whether an assessment is worthwhile.

NANO ACi stands for Non-Arthroscopic, Needle-Delivered, One-Stage Autologous Chondrogenic Injection. Each word describes how Professor Lee has redesigned the cartilage procedure.
No. It is Professor Lee’s surgical technique: a defined way to select, prepare, combine and precisely deliver three biological roles. Mytocel MSK, ChondroFiller and ArthroZheal are the tools used within that technique.
Three very small samples of the patient’s own auricular cartilage are taken from the bowl of the ear. Mytocel Autologous Micrografting Technology mechanically prepares that tissue into a micrograft solution at the point of care.
No. Traditional ACI and MACI use a staged pathway that harvests cartilage, grows cells in a laboratory and returns them during a later operation. NANO ACi is designed as a one-stage, point-of-care and needle-delivered technique.
No. The three components have relevant evidence in their own right, while the exact combined NANO ACi protocol is newer. Professor Lee assesses the whole joint and records prospective outcomes; no individual result can be guaranteed.
Continue Reading

Understand the complete cartilage pathway

Cartilage repair and regeneration

Cartilage repair and regeneration

Compare NANO ACi with established cartilage repair, Mytocel MSK and ChondroFiller.

Read more

Mytocel MSK

Mytocel MSK

See how the patient’s own tissue is prepared into autologous micrografts at the point of care.

Read more

Joint repair and regeneration

Joint repair and regeneration

Follow the tissue-specific family from cartilage to tendon, meniscus and bone.

Read more

Can this joint still be saved?

Begin with the whole joint, not the name of a treatment

cartilage patternalignmentstabilitybonepatient goals

Professor Lee’s assessment is designed to decide whether NANO ACi, another repair pathway or replacement is the right next step.

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