class="h4">Background
A s
caffold for treatment of deep osteo
chondral defe
cts should be stable, integrate well, and provide a surfa
ce for
chondro
cytes. To meet these demands, a biphasi
c s
caffold of allogenous sterilized bone with a
collagen surfa
ce was developed. Integration was tested in the sheep model.
class="h4">Material and methods
Cartilage chips were taken from the nonweight-bearing area of the left knee of 12 sheep and cultured. After 4聽wk a second procedure followed and defects of 9.4-mm diameter at the weight-bearing area of the medial femoral condyle of the right knee were created. The sterilized scaffold was inserted and the cultured autologous chondrocytes were dripped onto the surface. After 6聽wk, 3聽mo, and 6聽mo the animals were sacrificed; the explanted femoral condyles were evaluated macroscopically and using histologic, immunohistochemical, and electronmicroscopic methods.
class="h4">Results
After 6聽wk the level of the surface was well preserved, after 3聽mo parts of the scaffold were sintered but after 6聽mo the surface was continuous. Full integration of the allogenous bone could be observed after 6聽mo. The surface of the scaffold after 6聽wk consisted of bone, but after 3聽mo some chondrocytes and after 6聽mo a continuous chondral layer could be detected.
class="h4">Conclusions
The biphasic scaffold of allogenous bone and collagen proved to be stable and sufficiently integrated in the short- and midterm interval. Whether the chondrocytes on the surface had been derived from implanted chondrocytes or the scaffold with its surface was sufficiently chondroconductive must be answered in further investigations.
