MACI, which stands for Matrix Induced Chondrocyte Implantation, is an FDA-approved regenerative therapy procedure.  It uses your own cells to create durable repair tissue for knee cartilage damage.  The MACI procedure will help you reduce your knee pain, improve functionality, and provide long-lasting results.

Who Is MACI For?

Many common knee injuries are caused by wear and tear on the cartilage between the bones of the knee. Repetitive movements – like running or impact-related damage from sports injuries – can destroy your knees’ cartilage over time.  This wear & tear can lead to pain and a loss of range of motion. 

MACI Candidates for Cartilage Restoration Include Patients Are:

  • Between the ages of 17-55 with a single or multiple cartilage lesion without a diagnosis of arthritis
  • Have significant knee pain in the front of your knee that limits your ability to play sports or perform daily activities of your job or driving a car
  • Have Patellar instability with a cartilage defect (including the kneecap coming off its track and subluxing or dislocating).
  • Dissatisfied with the results of previous cartilage treatments you have had for your knee pain
  • Willing to dedicate yourself to a rehabilitation program following surgery

Conditions that MACI Could Help With Include:

  • Cartilage damage from repetitive action
  • Cartilage damage from trauma / traumatic events
  • Patella defect
  • Trochlea defect
  • Lateral femoral condyle defect w/ bone involvement defect

Daniel Romanelli, MD, FAAOS, is the only Board Certified Orthopedic Surgeon in the Rio Grande Valley that uses the MACI Procedure to repair common knee injuries with the patient’s own cartilage.

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How MACI Works

During an arthroscopic procedure of the knee, a sample of cartilage cells (about the size of two Tic Tacs) is removed from the patient’s knee and sent to a lab, where they are then embedded on a collagen membrane. After about 2-3 weeks, the cartilage cells then regenerate and form a repair tissue that is able to fill the cartilage defect.

Then, the surgeon will implant the membrane back into the knee, where the new cartilage tissue forms over time.

Full recovery — which includes a gradual return to easy daily activities, followed by moderate moves, such as walking or pool running, and then full sports functioning, such as running — takes nine to 12 months following surgery.

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What Happens After MACI Surgery?

The following is a general timeline of what to expect after MACI surgery:

  • Week 1: Very limited, light weight-bearing movements on crutches 
  • Weeks 2-3:  Gradual increase of weight, flexibility, and mobility with crutches
  • Weeks 4-6 : Work toward full weight-bearing movements and full range of motion
  • Weeks 7-12:  Full weight-bearing movement and range of motion without crutches
  • Months 3-6: Work toward full rehabilitation and strength building.
  • Months 6-9:  Walk 3-4 miles without symptoms and return to low-impact recreational activities
  • Months 9-12: Return to normal, pre-surgery activity levels