[Matrix-associated autologous chondrocyte transplantation (MACT). Minimally invasive technique in the knee].
OBJECTIVE
Repair of localized cartilage defects in the knee.


METHODS
Localized partial or full-thickness cartilage defects in the knee or osteochondral lesions (osteochondritis dissecans [OD]).


METHODS
Generalized cartilage defects, osteoarthritis, bacterial and rheumatoid arthritis, uncorrected axis deformities, ligament instability, patella instability, meniscectomy.


METHODS
Two-step procedure. 1. Diagnostic arthroscopy and cartilage biopsy for cell cultivation. 2. Minimalized arthrotomy. Defect debridement. Autologous cancellous bone grafting in OD. Glueing of the cell-loaded scaffold into the defect.


METHODS
Early functional rehabilitation with knee orthosis. Partial weight bearing (20 kg) for 6 weeks.


RESULTS
50 patients (24 female, 26 male, age 14-44 years, mean 30.3 years) with 58 focal cartilage defects (III-IV degrees) of the knee in the medial (n = 32) or lateral condyle (n = 5), patella (n = 14) and/or trochlea (n = 7) underwent matrix-associated autologous chondrocyte implantation (MACI). The mean follow-up was 24 months (21-29 months). The mean defect size was 4.1 cm2(1.6-6.1 cm2). The Lysholm Score improved from 57.3 to 87.4 points, the DGKKT (German Society of Autologous Cartilage and Bone Cell Transplantation) Score from 55.3 to 85.5 points. Pain on a visual analog scale (VAS) diminished from 5.5 to 2.1, while subjective function enhanced from 4.5 to 7.6. All scores were significant (p < 0.01; t-test). In eleven patients (twelve defects), a second-look arthroscopy revealed a mostly fibrocartilaginous regenerative tissue in 41.7% (5/12) and a mixed fibrous/hyaline regenerative tissue in 33.4% (4/12). 54% (27/50) of the patients estimated their result as excellent, 28% (14/50) as good, 16% as fair, and 2% (1/50) as poor.
Anders
Sven
S
Orthopädische Klinik für die Universität Regensburg, Asklepios Klinikum Bad Abbach, Bad Abbach. s.anders@asklepios.com
Schaumburger
Jens
J
Schubert
Thomas
T
Grifka
Joachim
J
Behrens
Peter
P
D000293:Adolescent; D000328:Adult; D001182:Arthroscopy / Q000379:methods*; D019902:Chondrocytes / Q000637:transplantation*; D005109:Extracellular Matrix / Q000637:transplantation*; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000601:surgery*; D008297:Male; D019060:Minimally Invasive Surgical Procedures / Q000295:instrumentation* / Q000379:methods*; D010007:Osteochondritis / Q000601:surgery*; D016896:Treatment Outcome; D055815:Young Adult