並列タイトル等発育期分離すべりモデルラットにおける下位椎体変形修復の骨化様式
一般注記Study design: A study using rat spondylolisthesis models.
Objective: To elucidate the mechanism for correction of vertebral rounding deformity.
Summary of Background Data: Vertebral rounding deformity is the strongest risk factor for high-grade slippage associated with spondylolisthesis in adolescents. We previously reported that inadequate endochondral ossification of the anterior upper corner of the vertebral growth plate in response to mechanical stress could be the pathological mechanism of vertebral rounding deformity.
Methods: We created a model of spondylolisthesis using 4-week-old rats. They were divided into a tail suspension group that underwent tail suspension to decrease mechanical stress starting at 2 weeks postoperatively and a ground control group with no intervention. Radiographs and micro-computed tomography scans were obtained once weekly for 6 weeks postoperatively. The lumbar spines were then harvested for histological analysis. Immunohistochemical studies detected types I, II, and X collagen in the growth plate cartilage. Bone histomorphometrical analysis was also performed.
Results: Radiological and histological evidence in the ground control group showed progress the rounding deformity with time as previously reported. Formation of normal cancellous bone was observed radiologically over time in the tail suspension group, indicating correction of rounding deformity. Histologically, the site showing radiological evidence of correction was derived from cartilage tissue. After starting tail suspension, the growth plate stained positive for type X collagen and the corrected site stained for types II and X collagen in a mosaic pattern. Chondrocytes expressing types I and II collagen and tartrate-resistant acid phosphatase-positive cells were also present at the corrected site. Histomorphometrically, more endochondral bone was detected at the corrected site than in the posterior aspect of the normal growth plate.
Conclusion: Correction of vertebral rounding deformity was associated with improvement of chondrocyte differentiation, furthermore, there is possible involvement of a third mechanism, namely transchondroid bone ossification.
It is possible to correct the rounding deformity of the vertebral body associated with isthmus slippage by decrease the load on the vertebral body in pediatric patients. In addition to improved chondrocyte differentiation and promotion of redifferentiation, there is possible involvement of a third mechanism, namely transchondroid bone ossification.
著作権情報This the final peer-reviewed manuscript is made available under the CC-BY-NC 4.0 license (http://creativecommons.org/licenses/by-nc/4.0/)
関連情報（DOI）10.1097/BRS.0000000000003779
連携機関・データベース国立情報学研究所 : 学術機関リポジトリデータベース（IRDB）（機関リポジトリ）