The MACI Procedure 

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, leading to pain and a loss of range of motion.

Tennessee Orthopaedic Clinics Dr. Mike Casey uses the MACI Procedure for knee surgery to repair common knee injuries with the patient’s own cartilage with great success.

MACI – Matrix Associated Chondrocyte Implantation – helps patients recover their lost knee function and eliminate pain by using a patient’s own cartilage to grow new cartilage, which is used to repair the damaged knee. 

Cartilage acts as a cushion between the bones, making sure joints move smoothly and without pain. When cartilage is damaged, joints may click, pop, hurt, and not move as they should.

Because cartilage cannot heal on its own, cartilage-based injuries will worsen over time if left untreated. If conservative treatments have not relieved your knee pain, you may be a candidate for MACI surgery.

Once you and your surgeon determine you are candidate for MACI, a small biopsy will be taken from the cartilage in your knee.

The biopsied cartilage is sent to a lab where it will be used to grow new, healthy cartilage for 4-6 weeks. This new batch of bio-identical cartilage is called the MACI membrane.

Your surgeon will cut the MACI membrane to fit the area where your damaged cartilage was removed. The MACI membrane will be inserted and glued into place. Once placed, the new cartilage will adhere to the damaged area and fill in and repair the injured area. The film will dissolve away on its own.

Every MACI patient we treat follows a custom-created rehabilitation program, beginning the day of your 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

MACI Procedure Locations