Tehran University Medical Journal

Failed back surgery syndrome (FBSS) is many a times an intractable problem confronted in patients with surgical disease of lumbar spine and at the same time is a pressing problem for the physicians as well. This clinical entity is defined as continuation of pain in the lumbar region and lower extremities following surgery of the lumbar spine. Knowledge of the etiological factors and their prevention is the best line of treatment to overcome the evolution of this syndrome. During this study, which was conducted in Imam Khomeini hospital Tehran from the year 1989 till 1990, 43 out of 114 patients developed "FBSS". 23 cases responded to conservative treatment and psychotherapy whereas medical treatment failed to achieve fruitful results in the rest. The latter underwent extensive radiological investigations and repeat surgery. According to this study, we recommend that in the initial management of these patients. The surgeon should observe the dictum of "5-mis" to overcome and minimize the "FBSS" entity

There are many studies about epidural fibrosis after surgical manipulation of the spine. We have studied formation of the post laminectomy epidural fibrosis after application of two materials (Silicone and Teflon) in this report. This expriment is on two groups of rats. Two separated laminectomies were done in each rat, one serving as control while in the other laminectomy spaces Silicone was used in group A and Teflon in group B. Laminectomy spaces were evaluated with gross dissection and histologic studies after 6 weeks. Silicone decreased intermuscular scar, deep scar, dural adhesion and collagen fiber density in epidural space. Teflon decreased dural adhesion and collagen fiber density but did not decrease intermuscular and deep scar formation in epidural space.

Introduction: As spinal cholinergic receptors exhibit an action against somatic pain, this effect could be potentiated by intrathecal injection of cholinesterase inhibitor-neostigmine. This study was designed to evaluate the role of interathecal neostigmine on local back pain relief after single level lumbar disc surgery.

Methods and Materials: In an interventional-expremental study (Imam Khomeini Hospital, Jun. 2000 to sep. 2001), sixty-six patient with unilateral herniated lumbr disc at one lumber space were randomely allocated into two groups including, control (C) group and Neostigmine (N) group. Both groups underwent fenestration employing same anesthetic techniques. At the end of surgery 2 ml normal saline in groups C and 100 micrograms neostigmine methylsulfate (0.2 ml combined with 1.8 ml normal saline) in group N were injected intrathecally postoperative local back pain was measured with 10 cm chart method using Visual Analogue Scale (VAS) at 1, 4, 8 and 12 hours. Total dosage of morphine, as an analgesic rescue, used during the first 24 hours following surgery and observed complications were recorded.

Results: Mean VAS score postoperatively at 1st and 4th hours were 2.24 (Standard Error Mean, SEM=0.36) and 1.82 (SEM=0.28) in group N and 5.36 (SEM=0.39) and 5.61 (SEM=0.37) in group C respectively. Mean morphine used in the first 24 hours was 0.9 (SEM=0.4) in group N and 4.7 (SEM=0.65) mg in group C. All result were found to be statistically different in the two group (P<0.05). There was no neurologic deficit or CSF leakage in both groups postoperatively. Regarding nausea and vomiting, the difference between two groups C (15 percent) and N (24.2 percent) were not significant statistically.

Conclusion: In this study, we have found that injection of 100 micrograms hyperbaric neostigmine intrathecally is a safe and effective method with minimal complications or side effect for pain relief and curtails postoperative opiate demand.