Describe the cartilage defects, patient characteristics, and clinical outcomes for adult patients treated with MACI® (autologous cultured chondrocytes on porcine collagen membrane) for cartilage restoration to the patella.
Following institutional review board approval, data were collected for patients treated by 10 surgeons between Jan 2017 and Sep 2019. Patient demographics, cartilage defect characteristics, and concomitant surgical procedures were summarized with descriptive statistics. All patient demographics and cartilage defect characteristics were entered in the database although collection of final clinical and patient reported outcomes is ongoing.
A total of 136 patients that received MACI treatment to the patella were available for analysis. The population was predominantly female (68%), mean age of 32 years, and BMI of 26.4 kg/m2. A majority of patients had undergone multiple previous knee surgeries. The most common prior surgical procedures, aside from chondroplasty/abrasion arthroplasty done at the time of the cartilage biopsy, were cartilage debridement (65%), loose body removal (15%), and meniscectomy (13.2%).
The average MACI treated patellar defect was 4.6 cm2. Approximately 20% of patients had a bipolar trochlear defect treated with MACI, and 17% of patients also had a MFC defect treated with MACI. The mean non-patella defect size was 4.4 cm2. At the time of MACI implantation, 46% of patients had a concomitant tibial tubercle osteotomy and 32% underwent medial patellofemoral ligament repair/reconstruction.
Two patients where the largest treated defect was the patella were considered treatment failures due to graft failure and requirement for major revision (both patients received osteochondral allografts with concomitant TTO within 2 years of MACI surgery).
This is the first multicenter report of patient and cartilage defect characteristics for patients receiving MACI implantation in the patella. Clinical and patient-reported outcomes will be included in the final presentation.