Technique of all arthroscopic autologous chondrocyte implantation (ACI) for the treatment of cartilage defects in the knee

Abstract

All arthroscopic treatment of deep cartilage defects in the knee for reconstruction of the articular surface. Focal cartilage defects of the knee (ICRS ≥ grade3) from asize of 2.5 cm2 and more. Osteoarthritis (Kellgren-Lawrence > grade2), osseus defect situation, cartilage lesion of the opposing articular surfaces (ICRS > grade2), instability, malalignment (>3-4°), inflammatory joint diseases. First procedure (cell harvesting): Treatment of additional pathologies, preparation of the cartilage defect, harvesting of osteochondral cylinders for cell culture. Second procedure (cell implantation): Dry arthroscopy, cleaning and drying of the already prepared defect, implantation of the in situ crosslinking cartilage cell suspension. First procedure (cell harvesting): Early functional treatment with weight bearing as tolerated. Second procedure (cell implantation): No drains, extension brace for 4days, then free range of motion, partial weight bearing for 4weeks in patellofemoral implantation and for 8weeks in tibiofemoral implantation, continuous passive motion beginning in postoperative week2, cycling from postoperative week9. In the literature, results for ACI in the knee are reported to be good, especially for larger cartilage defects. Arthroscopic techniques should lead to adecrease of complications and perioperative morbidity. No technique-specific complications occurred in our cohort. From 2012-2015, 98patients were treated using the above mentioned technique, whereby 62patients were retrospectively evaluated after 31.0 ± 14.8 (12.5-61.4) months. In 15patients (28%) additional procedures were performed (7anterior cruciate ligament reconstructions, 3correction osteotomies and 5medial patellofemoral ligament reconstructions). Average cartilage defect size was 4.7 ± 2.8 cm2, in 18patients (29%) more than one cartilage defect was treated. The subjective IKDC and total KOOS scores resulted in 66 ± 10 and 73 ± 19points.