OBJECTIVETo look into the character of the expression of collagen type II and transforming growth factor beta1 (TGF-beta1), basic fibroblast growth factor (bFGF) in the apical articular process cartilages of adolescent idiopathic scoliosis (AIS) and congenital scoliosis (CS) patients.

METHODSThe articular processes of 22 AIS and 18 CS were collected. The techniques of HE staining, immunohistochemistry and in situ hybridization were adopted in this research. By comparing the apical processes with the end processes, the convex processes with the concave processes, the AIS processes with CS processes, the pathological changes of the articular process cartilages of these patients and the distribution of collagen type II and TGF-beta1, bFGF in them were studied. The images of immunohistochemistry and in situ hybridization were input into the image analysis system and were analyzed semi-quantitatively. The SAS software (8.01) was adopted, and P < 0.05 was defined as the significant level.

RESULTSThe expression of collagen type II and TGF-beta1, bFGF in AIS was similar to CS: the concave sides of apexes were higher than the convex sides. The comparisons had statistical significance. There was no statistical significance between upper and lower end vertebrae in convex and concave sides, between convex and concave sides in upper and lower end vertebrae. The apical vertebrae were significantly higher than the ipsilateral sides of upper or lower end vertebrae for collagen type II. There was no statistical difference of the expression at the concave, convex, upper, lower end vertebrae between AIS and CS.

CONCLUSIONSThe cartilages of the apical processes show some signs of regression and hypoplasia in scoliosis. The concave side is more severe than the convex side. Increase of collagen type II and TGF-beta1, bFGF in the concave sides of apical processes in scoliosis may be the results of reconstruction of extracellular matrix and the compensation reactions which are caused by abnormal biomechanical forces such as compressive stresses. Compressive stress on the concave sides has more influences on the expression of collagen type II than tensile stress on the convex sides.