Türk Nöroşirürji Dergisi 1999 , Vol 9 , Num 3
PARAVERTEBRAL MUSCLE HERNIATION: A MODEL FOR THE HISTOPATHOGENESIS OF PERIDURAL FIBROSIS
Bilgehan BİLGE1, Serhat ERBAYRAKTAR2, Alp KILIÇALP3, Arif ÖSÜN2, Ümit ACAR2
1Özel Yücelen Hastanesi, Bodrum Muğla
2Dokuz Eylül Üniversitesi Tıp Fakültesi Nöroşirürji Anabilim Dalı, İzmir
3Dokuz Eylül Üniversitesi Tıp Fakültesi Patoloji Anabilim Dalı, İzmir
In this study, we tried to investigate the histological changes that occur in the paravertebral muscles, when a portion of it is under compression in the event of herniation through the lamina defect during the postoperative period. For this task, we used 15 rats. In all, a retraction lasting 20 minutes was applied onto the left paravertebral muscles as the control group (Group 1). While a herniation neck was formed with the ligature of a portion of the right paravertebral muscles in 8 rats (Group Ü), a pedicled muscle flap was transposed into a laminotomy defect in the other 7 rats (Group ÜI).The histological examination of the muscle biopsies of the third group revealed similar findings with the second group. They exhibited local ischemiae in the first day, coagulation necrosis in the seventh day, and fibrous healing at the end of the sixth week. These findings suggest that the paravertebral muscles may demonstrate the features of a local ischemiae with subsequent necrosis, and a fibrotic healing which is very close to the neural structures, when a portion of it is compressed within a surgically created lamina defect. So, we may explain the high incidence of peridural fibrosis after narrow laminotomy procedures with the fibrosis of the herniated and compressed part of paravertebral muscles. The fact that the myofibroblasts dominate the histologic appearance in peridural fibrosis, may support the validity of this mechanism. Anahtar Kelimeler : Adhesion, discectomy, peridural fibrosis, scarring