Time Matters: Why it's Important to Avoid Delays Between Biopsy and Knee Cartilage Repair Surgery Skip to content

Time Matters: Why it's Important to Avoid Delays Between Biopsy and Knee Cartilage Repair Surgery

Image of a knee cartilage lesion as it gets larger over time

Research finds “time matters” when it comes to delays between patient biopsy and MACI implantation surgery.

The study, “Time Matters: Knee Cartilage Defect Expansion and High-Grade Lesion Formation while Awaiting Autologous Chondrocyte Implantation” by Dr. David Flanigan and a team of researchers, shows that patients undergoing cell-based surgery experienced new cartilage defects and progression in existing cartilage defects during delays between cartilage biopsy and chondrocyte implantation.
 

The Study Findings

The study examined consecutive knee ACI and MACI cases by a single surgeon (128 knees in 111 patients).

Chart displaying the demographics and cartilage defect characteristics of patients participating in the study. Locations of high-grade cartilage defects at time of biopsy included medial femoral condyle, lateral femoral condyle, trochlea and patella. The medial femoral condyle defects were most numerous.

The mean time between cartilage biopsy and implantation was 155 days. In that time, patients’ cartilage defects expanded a mean of 0.6 cm2. Further, 16.2 percent of patients experienced new high-grade cartilage defects.

Chart displaying study results. The mean time between cartilage biopsy and implantation was 155 days. The average size of the primary defect at time of biopsy was 4.50 cm 2. In the time between biopsy and implantation primary defect size grew a mean of 0.6 cm2.  For every month (30 days) the implantation procedure was delayed, patients experienced a mean increase in defect size 0.11 cm2. New high-grade defects formed in 16.2 percent of patients.

Of those patients who developed a new high-grade cartilage defect, the most common new defect location was the patella.

Chart displaying the distribution of lesions in new high-grade cartilage defects from the “Time Matters” study. The patella was the most common location.

 

Who’s at Greatest Risk?

The study found that patients who were male, had smaller initial defect sizes, and longer time between surgeries were at greater risk for defect expansion.

Man experiencing knee cartilage pain.

Why Do Delays Occur?

Delays between biopsy and implantation can be affected by several variables, including chondrocyte processing, insurance approval, patient factors (preference for timing, deductibles, life events, etc.) and surgeon scheduling.
 

How Should you Advise Patients on Surgery Schedules?

Surgeons, patients, insurance, and industry should coordinate efforts to expedite the time between biopsy and implantation to prevent further deterioration of the knee joint and obtain better patient outcomes, the study authors wrote.

Please see below for full indication and ISI.

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Indication and Important Safety Information

Important Safety Information

Contraindications: MACI is contraindicated in patients with a known history of hypersensitivity to gentamicin, other aminoglycosides, products of porcine or bovine origin; in patients with severe osteoarthritis of the knee, inflammatory arthritis, inflammatory joint disease, or uncorrected congenital blood coagulation disorders; 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; or in patients unable to cooperate with a physician-prescribed post-surgical rehabilitation program.

Warnings and Precautions:
  • Malignancy: The risk of MACI in patients with malignancy in the area of cartilage biopsy or implant is unknown. Expansion of malignant or dysplastic cells present in biopsy tissue during manufacture and subsequent implantation may be possible.
  • Transmissible infectious diseases: Because patients undergoing procedures associated with MACI are not routinely tested for transmissible infectious diseases, cartilage biopsy and MACI implant may carry risk of transmitting infectious diseases.
  • Presurgical Comorbidities: Local inflammation or active infection in the bone, joint, and surrounding soft tissue, meniscal pathology, cruciate ligament instability, and misalignment should be assessed and treated prior to or concurrent with MACI implantation.
  • Product Sterility: Final sterility test results are not available at the time of shipping.

Adverse Reactions: 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.

Specific Populations:
  • Use of MACI in pediatric patients (younger than 18 years of age) or in patients over 65 years of age has not been established.
  • The MACI implant is not recommended during pregnancy. For implantations post-pregnancy, the safety of breastfeeding to an infant has not been determined.

To report negative side effects, contact Vericel Corporation at 1-800-453-6948 or FDA at 1-800-FDA-1088 (1-800-332-1088) or www.fda.gov/medwatch.

Please see Full Prescribing Information.

Indication

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

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

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.