Clinical Decision-Making: When Is Multi-Focal MACI Knee Cartilage Repair Ideal? Skip to content

Clinical Decision-Making: When Is Multi-Focal MACI Knee Cartilage Repair Ideal?

Runner experiencing knee pain

MACI offers the flexibility to treat cartilage defects in multiple areas of the knee, and surgeons sometimes turn to the MACI procedure to treat patients with multi-focal knee cartilage damage.

What to consider in your clinical decision-making process?

The “Problem List”

When making clinical decisions, Dr. Seth Sherman, an orthopedic surgeon, says he always starts by developing a “problem list” for each patient. This is usually informed by bi-lateral weightbearing X-rays of the patient as well as an MRI, which helps guide the decision-making process for surgical vs. non-surgical treatments.

When to Choose Surgery

Surgery might be warranted, for example, if the MRI reveals intra-articular loose bodies of knee cartilage. Dr. Sherman might choose surgery and then during the arthroscopy he can remove the loose bodies and also prepare for the MACI procedure by measuring any chondral defects and taking a MACI biopsy.

The Case for Treating Multi-Focal Cartilage Defects with MACI

If a patient has multi-focal, unipolar chondral defects, and is young1 and healthy, Dr. Sherman might also choose to pursue MACI. This could be the case, for example, with patella and lateral femoral chondral defects in the same knee of a patient experiencing patellar instability and/or pain.

How Common are Multiple Cartilage Defects?

Treatment of multiple cartilage defects represents about 30% of cases, according to a study of the first 1,000 patients to undergo the MACI knee cartilage repair procedure.2

Find more information on best practices for MACI knee cartilage repair here.

Please see below for full indication and ISI.

References 1. MACI has not been studied in patients younger than 18 or over 55 years of age. 2. Carey J, Remmers A, Flanigan D. Use of MACI (Autologous Cultured Chondrocytes on Porcine Collagen Membrane) in the United States. The Orthopaedic Journal of Sports Medicine. [Internet]. 2020 August;8(8):1-7

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MACI repairs knee cartilage using your patient’s own chondrocytes

Indication and Important Safety Information

Important Safety Information

MACI is contraindicated in patients with a known history of hypersensitivity to gentamicin, other aminoglycosides, or products of porcine or bovine origin. MACI is also contraindicated for patients with severe osteoarthritis of the knee, inflammatory arthritis, inflammatory joint disease, or uncorrected congenital blood coagulation disorders. MACI is also not indicated for use in patients who have undergone prior knee surgery in the past 6 months, excluding surgery to procure a biopsy or a concomitant procedure to prepare the knee for a MACI implant.

MACI is contraindicated in patients who are unable to follow a physician-prescribed post-surgical rehabilitation program.

The safety of MACI in patients with malignancy in the area of cartilage biopsy or implant is unknown. Expansion of present malignant or dysplastic cells during the culturing process or implantation is possible.

Patients undergoing procedures associated with MACI are not routinely tested for transmissible infectious diseases. A cartilage biopsy and MACI implant may carry the risk of transmitting infectious diseases to healthcare providers handling the tissue. Universal precautions should be employed when handling the biopsy samples and the MACI product.

Final sterility test results are not available at the time of shipping. In the case of positive sterility results, health care provider(s) will be contacted.

To create a favorable environment for healing, concomitant pathologies that include meniscal pathology, cruciate ligament instability and joint misalignment, must be addressed prior to or concurrent with the implantation of MACI.

Local treatment guidelines regarding the use of thromboprophylaxis and antibiotic prophylaxis around orthopaedic surgery should be followed. Use in patients with local inflammations or active infections in the bone, joint, and surrounding soft tissue should be temporarily deferred until documented recovery.

The MACI implant is not recommended during pregnancy. For implantations post-pregnancy, the safety of breast feeding to infant has not been determined.

Use of MACI in pediatric patients (younger than 18 years of age) or patients over 65 years of age has not been established.

The most frequently occurring adverse reactions reported for MACI (≥5%) were arthralgia, tendonitis, back pain, joint swelling, and joint effusion.

Serious adverse reactions reported for MACI were arthralgia, cartilage injury, meniscus injury, treatment failure, and osteoarthritis.

Please see Full Prescribing Information for more information.


MACI® is an autologous cellularized scaffold product that is indicated for the repair of single or multiple symptomatic, full-thickness cartilage defects of the adult knee, with or without bone involvement.

MACI® (autologous cultured chondrocytes on porcine collagen membrane) is an autologous cellularized scaffold product that is indicated for the repair of single or multiple symptomatic, full-thickness cartilage defects of the adult knee, with or without bone involvement.

MACI is intended for autologous use and must only be administered to the patient for whom it was manufactured. The implantation of MACI is to be performed via an arthrotomy to the knee joint under sterile conditions.

The amount of MACI administered is dependent upon the size (surface in cm2) of the cartilage defect. The implantation membrane is trimmed by the treating surgeon to the size and shape of the defect, to ensure the damaged area is completely covered, and implanted cell-side down.

Limitations of Use

Effectiveness of MACI in joints other than the knee has not been established.

Safety and effectiveness of MACI in patients over the age of 55 years have not been established.