ABSTRACT
<p><b>OBJECTIVE</b>To compare the cell viability of chondrocytes between the anterior and the posterior spinal growth plates in adolescent idiopathic scoliosis (AIS) by proliferation and apoptosis labelling.</p><p><b>METHODS</b>Seventeen AIS patients (4 male and 13 female, mean age 13.6 years old, ranged from 10 to 17 years old) were recruited in this study. Growth plates were harvested during anterior and posterior surgery. PCNA (proliferating cell nuclear antigen) and TUNEL (terminal deoxynucleotide transferase-mediated nick end labeling) were used for proliferation and apoptosis labeling on chondrocytes respectively.</p><p><b>RESULTS</b>In AIS, the distribution of the proliferating nests were denser and more parallel in anterior column than those in posterior under microscope observation. In the proliferative and hypertrophic zone the PCNA index and PCNA/TUNEL ratio were higher in the anterior column than those in the posterior column (P < 0.05 and P < 0.01 respectively). While in resting zone the differences were not so significant.</p><p><b>CONCLUSION</b>In adolescent idiopathic scoliosis the growth viability of chondrocytes is more vigorous in anterior spinal column than in the posterior column.</p>