Orthopedic surgeon Sverre Løken has in his thesis shown that patients treated with Autologous Chondrocyte Implantation (ACI) in the knee improved their joint function but they did not obtain normal cartilage and they did not regain normal muscle strength.
Articular cartilage is a highly specialized tissue developed for load distribution and low friction movement.
Cartilage injuries often affect young people and can make sports participation impossible and can lead to work disability at young age.
In this thesis, supervised by professor Lars Engebretsen, analyses of the repair tissue following ACI showed a fibrous repair tissue different from normal hyaline cartilage.
Cartilage injuries in approximately 2/3 of the knees
In a study of almost 1,000 patients who underwent arthroscopy of the knee, cartilage injuries were detected in approximately 2/3 of the knees, while deep cartilage injuries down to the subchondral bone and with an area of more than 2 cm2 were found in about 6%.
When the patients diagnosed with a cartilage injury were re-examined after 6-7 years, the knee function had improved both in patients who had undergone cartilage repair and in patients who had not been treated for their cartilage injury. However, in both groups knee function was still impaired.
Stem cells are "mother cells" that can develop into more specialized cells. Mesenchymal stem cells can differentiate into cartilage cells and also other cell types.
In a part of this thesis cartilage injuries in rabbits were treated with a biomaterial (hyaluronan scaffold) supplemented with autologous mesenchymal stem cells cultivated from the rabbit’s bone marrow. Defects treated with stem cells did not show a significantly better repair compared to defects treated without cells (empty biomaterial).
Further studies are needed to design the optimal way to stimulate stem cells to produce normal articular cartilage in an injured area.
Read more about Sverre Løkens projects.
Head: Professor Olav Reikerås, Ortopedisk avdeling, Klinikk for hode, bevegelse og rekonstruktiv kirurgi, Universitetet i Oslo
1. opponent: Professor Mats Brittberg, Cartilage Research Unit, Kungsbacka Hospital, Sahlgrenska akademin, University og Gothenborg, Sweden
2. opponent: Professor Jón Karlsson, Department of Orthopaedics, Sahlgrenska akademin, University og Gothenborg, Sweden
3. opponent: Professor Ellen-Cecilie Treu Røe, Avdeling for fysikalsk medisin og rehabilitering, Klinikk for hode, bevegelse og rekonstruktiv kirurgi, University of Oslo, Norway
14.15 - 15.00 Trial lecture (April 8)
10.15 - 13:15 PhD presentation and defense (April 9)