脊髓空洞源性脊柱侧凸椎旁肌超微结构的比较观察

Comparison of ultrastructure of paravertebral muscles in scoliosis secondary to syringomyelia

目的比较观察脊髓空洞源性脊柱侧凸患者椎旁肌超微结构病理改变的特征,探讨脊柱侧凸的发生机制。方法全部病例分为三组:脊髓空洞源性脊柱侧凸(SS)组12例,青少年特发性脊柱侧凸(AIS)组5例,非脊柱侧凸(NS)组2例。术中切取患者两侧骶棘肌组织,分别进行光镜和电镜观察。结果SS组有2例患者出现小群性肌萎缩,1例发生周围神经脱髓鞘,7例可见靶纤维或靶样纤维。与AIS组相比,SS组患者骶棘肌的超微结构明显异常。表现为肌质网普遍扩张,线粒体肿胀形成髓鞘样结构,胞质内散在脂滴增多,肌原纤维间糖原聚集,糖原湖形成。结论脊髓空洞源性脊柱侧凸患者存在椎旁肌失神经支配现象,椎旁肌超微结构的异常以胞浆中细胞器为主,而肌原纤维的病变较轻。SS患者椎旁肌超微结构的异常程度明显比AIS严重,这可能与其椎旁肌发生失神经支配有关。

Objective To evaluate the ultrastructural features of paravertebral muscles by electron microscopic examination,and investigate the pathogenesis of scoliosis secondary to syringomyelia. Methods This series included 12 cases with scoliosis secondary to syringomyelia （SS）, 5 cases with adolescent idiopathic scoliosis （AIS）, and 2 without scoliosis （NS）. Paravertebral muscles of all the patients were observed under light and electron microscope, Results In SS group, grouping atrophy of muscular fibers occurred in 2, demyelination of peripheral nerves in 1, and target or torget-like fibers in 7. The ultrastructural changes of paravertebral muscles in SS group were as follows： diffusive sarcoplasmic reticulum dilatation, mitochondria swelling and myelin figure forming, lipid granule increasing and hepatin conglomeration, which were more severe than those in MS group. Conclusion Denervation of paravertebral muscles is present in patients with scoliosis secondary to syringomyelia. The ultrastructural changes are apt to occur in cytoplasmic organelles rather than in myofibrillae. More severe ultrastructural abnormity in SS in contrast to AIS attributes to the denervation of paravertebral muscles.