The CartiHeal™ Agili-C™ implant is an FDA-approved option for repairing damaged cartilage in the knee, including in knees that already have mild to moderate arthritis. It is a small, porous scaffold made from aragonite, a natural form of calcium carbonate, that is placed into the damaged area so the body can regrow cartilage and the bone beneath it. Dr. Andrew Dold, a board-certified, fellowship-trained sports medicine surgeon in Frisco, Texas, offers CartiHeal Agili-C alongside the full range of cartilage repair and transplant procedures.
- FDA approved in 2022 for cartilage and osteochondral (cartilage and bone) defects in the knee
- For damaged areas of about 1 to 7 square centimeters
- Approved for knees with no, mild or moderate arthritis (Kellgren-Lawrence grade 0 to 3)
- Single surgery; no donor tissue and no cells grown in a lab
- Gradually absorbed by the body and replaced by your own tissue
What is CartiHeal Agili-C?
Agili-C, made by Smith+Nephew, is a cell-free, off-the-shelf implant. It has two layers: one that sits in the bone and one that sits at the level of the cartilage. Its porous structure, made from purified aragonite derived from coral, acts as a framework that the body’s own cells grow into, rebuilding both the cartilage surface and the bone underneath. Over time the implant is absorbed; according to the manufacturer, it is largely resorbed within about 18 months.
Because it treats both cartilage and the bone beneath it, it can be used for cartilage defects from injury, wear or osteochondral lesions.
Who is a candidate?
- Knee pain from a cartilage or osteochondral defect seen on MRI (ICRS grade 3 or higher)
- A damaged area of about 1 to 7 square centimeters
- No arthritis, or mild to moderate arthritis (not severe, bone-on-bone arthritis)
- Symptoms that have not improved with non-surgical treatment
Agili-C is not appropriate for knees with severe arthritis, very deep bone defects (more than about 8 mm), defects without healthy surrounding bone, or active infection. Problems such as poor leg alignment, an unstable kneecap, a torn ACL or a damaged meniscus may need to be treated as well, sometimes at the same time. For severe arthritis, osteotomy or knee replacement may be better options.
What does the research show?
Agili-C was approved by the FDA in March 2022 based on a randomized clinical trial of 251 patients that compared it with the standard treatments of microfracture or debridement (cleaning up damaged cartilage). At two years, patients treated with Agili-C had about twice the improvement in knee pain and function scores (KOOS) compared with the standard-treatment group. As with any procedure, individual results vary, and Dr. Dold will discuss what is realistic for your knee.
What happens during the procedure?
The procedure is typically outpatient. The knee is first examined with an arthroscope (a small camera) to confirm the size and location of the damage. The implant is then placed through a small open incision: the damaged area is prepared, a precisely sized hole is made, and the implant is press-fit into place just below the level of the surrounding cartilage. Larger areas may need more than one implant.
Recovery
Recovery is gradual because new cartilage and bone take time to form. As a general guide, physical therapy starts within the first couple of weeks, crutches are used for a period to protect the knee, and most patients regain normal walking and motion over about 3 months. Many notice meaningful improvement by about 6 months, and return to higher-impact activities and sports often takes 9 to 12 months. Dr. Dold will give you a specific rehabilitation plan based on the size and location of your repair and any other procedures performed.
Watch Dr. Dold explain CartiHeal Agili-C
Latest research: 5-year results
Since this page was first written, longer follow-up from the pivotal U.S. and international trial has been published. At 5 years, patients treated with Agili-C continued to show significantly greater improvement in knee pain and function than those treated with microfracture or debridement, with about three in four patients meeting the trial’s responder definition. Benefits were seen regardless of lesion location and in both women and men. Independent cohort studies and a systematic review of more than 500 patients report similar improvements and low failure rates. The pivotal trial was funded by the manufacturer, and long-term data beyond 5 years are still limited.
Why see Dr. Dold
- Board certified by the American Board of Orthopaedic Surgery, with subspecialty certification in Sports Medicine
- Sports medicine and arthroscopy fellowship at NYU Langone / Hospital for Joint Diseases; orthopedic residency at the University of Toronto
- Fellow of the American College of Surgeons (FACS), the American Academy of Orthopaedic Surgeons (FAAOS), the American Orthopaedic Association (FAOA) and the Royal College of Surgeons of Canada (FRCSC)
- Published research on knee ligament and meniscus surgery, including The Posteromedial Corner of the Knee (JAAOS, 2017) and transtibial meniscal root repair (KSSTA, 2017)
- Team physician and surgical consultant to Rugby Canada; has cared for professional and Olympic athletes from the NFL, NBA, NHL, MLS, PGA Tour, Major League Rugby and USA Gymnastics
- D Magazine Best Doctors (Collin County), 2019–2026 · Rated 4.9 on Google
Frequently asked questions
What is CartiHeal Agili-C?
An FDA-approved implant made from aragonite, a natural form of calcium carbonate, that is placed into a damaged area of knee cartilage in a single surgery. It acts as a scaffold for the body to regrow cartilage and the bone beneath it, and is gradually absorbed.
Is CartiHeal FDA approved?
Yes. The Agili-C implant received FDA premarket approval in March 2022 for cartilage and osteochondral defects in the knee.
Can CartiHeal be used if I have arthritis?
It is approved for knees with no, mild or moderate arthritis (Kellgren-Lawrence grade 0 to 3). It is not used for severe, bone-on-bone arthritis.
How is CartiHeal different from microfracture?
Microfracture makes small holes in the bone so marrow can form repair tissue. Agili-C places a scaffold that supports regrowth of both cartilage and the bone beneath it, and in the trial used for FDA approval it showed greater improvement than microfracture or debridement at two years.
How is CartiHeal different from MACI?
MACI requires two surgeries: one to collect cartilage cells, which are grown in a lab, and a second to implant them. Agili-C is an off-the-shelf implant placed in a single surgery, with no donor tissue or lab-grown cells.
How long is recovery after CartiHeal?
Physical therapy starts early, most patients regain normal walking and motion over about 3 months, and return to higher-impact activities and sports often takes 9 to 12 months. Your plan depends on your repair.
Is CartiHeal covered by insurance?
Coverage varies by insurance plan, so it is worth checking with your insurer before surgery.
Research cited on this page
- Altschuler N, Zaslav KR, Di Matteo B, et al. Aragonite-based scaffold versus microfracture and debridement for the treatment of knee chondral and osteochondral lesions: results of a multicenter randomized controlled trial. Am J Sports Med. 2023;51(4):957-967. PubMed
In 251 patients at 26 centers, including knees with mild to moderate arthritis, the implant group improved about twice as much on the KOOS score at 2 years. 77.8% vs 33.6% had a large improvement, and failure rates were 7.2% vs 21.4%. - Altschuler N, Zaslav KR, Di Matteo B, et al. Five-Year Follow-up of a Multicenter Randomized Controlled Trial Comparing an Aragonite-Based Scaffold With Microfracture and Debridement for Chondral and Osteochondral Knee Lesions. Am J Sports Med. 2026;54(6):1376-1385. PubMed
Five-year follow-up of the pivotal trial: KOOS improvement remained significantly greater with the implant (22.6-point difference), with a 74.7% responder rate. - Conte P, Anzillotti G, Crawford DC, et al. Differential analysis of the impact of lesions’ location on clinical and radiological outcomes after the implantation of a novel aragonite-based scaffold to treat knee cartilage defects. Int Orthop. 2024;48(12):3117-3126. PubMed
Trial analysis: the implant outperformed microfracture/debridement regardless of lesion location up to 4 years, with more defect filling on MRI. - Kon E, De Caro F, Dasa V, et al. Female patients report comparable results to males after the implantation of an aragonite-based scaffold for the treatment of knee chondral and osteochondral defects: a gender-based analysis of a RCT at 4 years’ follow-up. J Orthop Traumatol. 2025;26(1):17. PubMed
Trial analysis: women and men had comparable results with the implant through 48 months, both better than controls. - McKeeman JD, Jain N, Wang N, et al. Aragonite-Based Scaffolds Are Effective Osteochondral Graft Substitutes for Osteochondral Defects of the Knee: A Systematic Review. Arthrosc Sports Med Rehabil. 2025;7(5):101215. PubMed
Systematic review of 526 patients: improved patient-reported outcomes and low failure rates at 12 to 78 months. - de Caro F, Vuylsteke K, Van Genechten W, et al. Acellular Aragonite-Based Scaffold for the Treatment of Joint Surface Lesions of the Knee: A Minimum 5-Year Follow-Up Study. Cartilage. 2024;15(4):399-406. PubMed
Cohort with minimum 5-year follow-up: KOOS improved from 45 to 86, with one failure. - Kon E, Di Matteo B, Verdonk P, et al. Aragonite-Based Scaffold for the Treatment of Joint Surface Lesions in Mild to Moderate Osteoarthritic Knees: Results of a 2-Year Multicenter Prospective Study. Am J Sports Med. 2021;49(3):588-598. PubMed
Multicenter study in mild to moderate knee arthritis: significant improvement in all KOOS subscales at 24 months. - Van Genechten W, Vuylsteke K, Struijk C, et al. Joint Surface Lesions in the Knee Treated with an Acellular Aragonite-Based Scaffold: A 3-Year Follow-Up Case Series. Cartilage. 2021;13(1_suppl):1217S-1227S. PubMed
Prospective study in young, active patients: KOOS pain improved by about 41 points at 36 months. - Kon E, Robinson D, Verdonk P, et al. A novel aragonite-based scaffold for osteochondral regeneration: early experience on human implants and technical developments. Injury. 2016;47 Suppl 6:S27-S32. PubMed
First-in-human study: the tapered implant design lowered the revision rate to 0% versus 10.5% with the earlier cylindrical design. - Amin NH, Faucett SC, Qin C, et al. Clinical Experience With an Aragonite-Based Scaffold Implant for Knee Cartilage Repair: A Multicenter Case Series. Cureus. 2025;17(6):e86127. PubMed
U.S. clinical experience: pain scores improved from 6.6 to 3.9 after implantation. - Boffa A, Solaro L, Poggi A, et al. Multi-layer cell-free scaffolds for osteochondral defects of the knee: a systematic review and meta-analysis of clinical evidence. J Exp Orthop. 2021;8(1):56. PubMed
Review: multi-layer cell-free scaffolds show short- to mid-term clinical benefit with few failures. - Kluyskens L, Debieux P, Wong KL, et al. Biomaterials for meniscus and cartilage in knee surgery: state of the art. J ISAKOS. 2022;7(2):67-77. PubMed
Review comparing cartilage biomaterials including Agili-C; results support individualized use and standardized evaluation.
CartiHeal and Agili-C are trademarks of Smith+Nephew. Dr. Dold is a consultant for Smith+Nephew.
Medically reviewed by Andrew P. Dold, MD, FAOA, FAAOS, FACS, FRCSC. Last reviewed October 2026. This page is general information, not medical advice. Individual results vary.
