Preventing peridural fibrosis with nonsteroidal anti-inflammatory drugs

Peridural fibrosis is one of the more frequent complications of lumbar surgery. Nonsteroidal anti-inflammatory drugs inhibit the inflammatory and fibroblastic response. We performed lumbar laminectomies in 24 rabbits, divided into two groups. The experimental group received 5 mg/kg/day of aceclofenac for 7 days and the control group received 1 cm3 of physiological saline. The samples were stained using immunohistochemical methods. The cellular populations in the inflammatory reaction and the thickness of the fibrous membrane were quantified. The mean of the fibrous area was always less in the rabbits of the experimental group compared to controls (47% less at 2 weeks and 41% less at 4 weeks). We observed an 8% decrease in the number of fibroblasts with antivimentin monoclonal antibodies in the experimental group. In this model, aceclofenac inhibits the presence of inflammatory cells in the fibrous scar in the early stages and reduces the extension of adhesions without adverse reactions

Estudo de membrana biológica em ratos na prevenção de fibrose pós laminectomia Inhibition of peridural fibrosis after laminectomy using biological sheet in rat model

Os autores investigaram a aplicação de uma membrana biológica, constituída de cortical óssea bovina descalcificada, em cirurgias de coluna vertebral de ratos, com o intuito de tratar o defeito ósseo minimizando ou impedindo a herniação do tecido muscular para dentro do canal raquidiano pós laminectomia, inibindo a formação de fibrose pós-operatória e avaliando a biocompatibilidade do material. O estudo foi feito utilizando-se de ratos Wistar-EPM, que após intervalos de 8, 16 e 24 semanas, foram sacrificados, sendo removidas as peças cirúrgicas para análise anatomopatológica. A membrana biológica evitou a herniação do tecido muscular para o canal raquidiano, sendo totalmente reabsorvida em todas as peças analisadas, demonstrando sua biocompatibilidade e favorecendo a neoformação óssea e evitando aderências.<br>The prevention of fibrosis after lumbar and thoracic laminectomies by avoiding herniation of muscular tissue was studied using Wistar-EPM rats with a biological membrane made of decorticated bone of bovine material. The rats were sacrified after eight, sixteen and twenty four weeks and the materal was sent to anatomopathological study. This membrane proved to be biocompatible and its efficacy was seen by allowing formation of bone and preventing muscular tissue invasion of the epidural space and avoiding adherences

Prevention of epidural scarring after microdiscectomy: a randomized clinical trial comparing gel and expanded polytetrafluoroethylene membrane

A randomized clinical trial compared two materials used to prevent epidural scarring after microdiscectomy. To determine whether ADCON®-L Gel (ALG) or Preclude Spinal Membrane® (PSM) was more effective in preventing scarring, reducing pain, and improving quality of life postoperatively. Postdiscectomy syndrome may result from epidural scarring. Various materials have been used in attempts to prevent this problem, but none have provided optimal results. Previous laboratory and clinical studies have found ALG and PSM to be effective, but none compared the two materials. Thirty-one patients undergoing primary microdiscectomy were randomly assigned to receive either ALG or PSM. Postoperatively, patients were evaluated by magnetic resonance imaging (MRI), with contrast, for volume and rostral–caudal extent of scar tissue and nerve root involvement. Back and leg pain and quality of life were assessed by neurologic examinations and standardized patient surveys. Findings at any reoperations were recorded. Results in the PSM (n = 18) and ALG (n = 13) groups were compared statistically. No operative or postoperative complications occurred. Two patients in each group required reoperation. MRI at 6 months showed no, mild or mild-moderate scarring in most patients, with no significant differences between the ALG and PSM groups in scar volume and extent or nerve root involvement. Neurologic examinations and patient surveys showed substantial reductions in pain over time in both groups but no significant differences between groups. PSM was easy to see and remove at reoperation. PSM and ALG are equally effective in preventing epidural scarring associated with postdiscectomy syndrome