OBJECTIVETo 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.

METHODSSeventeen 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.

RESULTSIn 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.

CONCLUSIONIn adolescent idiopathic scoliosis the growth viability of chondrocytes is more vigorous in anterior spinal column than in the posterior column.

Adolescent ; Apoptosis ; Cell Proliferation ; Cell Survival ; Child ; Chondrocytes ; cytology ; Female ; Growth Plate ; pathology ; Humans ; Immunohistochemistry ; In Situ Nick-End Labeling ; Male ; Scoliosis ; pathology ; physiopathology ; Spine ; growth & development ; pathology

OBJECTIVETo evaluate the trabecular bone micro-structure from different sites of spine in adolescent idiopathic scoliosis patients. The target site consisted of the bilateral facet joints from apical vertebrae and from end vertebrae.

METHODSNine AIS patients with mean age 14.9 years (range 12-17 years) and mean Cobb angle 56 degrees (ranged 48 degrees-84 degrees) were recruited into this study. Corrective surgery was indicated to these patients, and facet joint biopsies were collected during decortications for spinal fusion. Biopsy consents were obtained from patients. Bone specimens were fixed with routine histology procedures and scanned by micro computer tomography (muCT40, Scanco Medical, Switzerland). Ten pairs of facet joint were harvested from apical vertebrae and 12 pairs from end vertebrae. Three-dimensional reconstructed images with the resolution of 20 microm were achieved for histomorphometric analysis.

RESULTSThe values of BV/TV (0.268 vs. 0.354, P < 0.05), TbTh (0.20 vs. 0.24, P < 0.05), TbSP (0.66 vs. 0.56, P < 0.05) and BS/BV (12.7 vs. 10.4, P < 0.05) between convex and concave side at the apex area were significantly different. No difference was found in any structural parameters between left and right side at end area, and upper thoracic (T5, 6) and thoracolumbar (T12, L1).

CONCLUSIONDue to asymmetric compression and tension shared between convex and concave side, more bone and thicker and more profound trabecular bones are observed in the concave side than in the convex side, which seems to resist the progression of spinal curvature. This finding suggests that the provocative factors which cause the progression of the curve in certain patients may not lie in the bone component of spine.

Adolescent ; Child ; Female ; Humans ; Scoliosis ; diagnostic imaging ; pathology ; physiopathology ; Tomography, X-Ray Computed ; Zygapophyseal Joint ; pathology ; physiopathology