Prior to the development of magnetic resonance imaging, the only way to ascertain the presence of arachnoiditis was by opening the dura. In the days of CT scanning and Pantopaque and later, Metrizamide myelography, the presence of arachnoiditis could be speculated based on radiographic findings. Often, myelography prior to the introduction of Metrizamide was the cause of arachnoiditis. It can also be caused by the long term pressure brought about with either a severe disc herniation or spinal stenosis. The presence of both epidural scarring and arachnoiditis in the same patient are probably quite common. Arachnoiditis is a broad term denoting inflammation of the meninges and subarachnoid space. A variety of causes exist, including infectious, inflammatory, and neoplastic processes. Infectious causes include bacterial, viral, fungal, and parasitic agents. Noninfectious inflammatory processes include surgery, intrathecal hemorrhage, and the administration of intrathecal (inside the dural canal) agents such as myelographic contrast media, anesthetics (e.g. chloroprocaine), and steroids (e.g. Depo-Medrol, Kenalog). Lately iatrogenic arachnoiditis has been attributed to misplaced Epidural Steroid Injection therapy when accidentally administered intrathecally. The preservatives and suspension agents found in all steroid injectates, which arent indicated for epidural administration by the U.S. Food & Drug Administration due to reports of severe adverse events including arachnoiditis, paralysis and death, have now been directly linked to the onset of the disease following the initial stage of chemical meningitis. Neoplasia includes the hematogenous spread of systemic tumors, such as breast and lung carcinoma, melanoma, and non-Hodgkin lymphoma.
Even less invasive forms of surgery are not uniformly successful; approximately 30,000–40,000 laminectomy patients obtain either no relief of symptomatology or a recurrence of symptoms. Another less invasive form of spinal surgery, percutaneous disc surgery, has reported revision rates as high as 65%. It is no surprise, therefore, that FBSS is a significant medical concern which merits further research and attention by the medical and surgical communities. Total disc replacement
Lumbar total disc replacement was originally designed to be an alternative to lumbar arthrodesis (fusion). The procedure was met with great excitement and heightened expectations both in the United States and Europe. In late 2004, the first lumbar total disc replacement received approval from the U.S. Food and Drug Administration (FDA). More experience existed in Europe. Since then, the initial excitement has given way to skepticism and concern. Various failure rates and strategies for revision of total disc replacement have been reported.The role of artificial or total disc replacement in the treatment of spinal disorders remains ill-defined and unclear. Evaluation of any new technique is difficult or impossible because physician experience may be minimal or lacking. Patient expectations may be distorted. It has been difficult to establish clear cut indications for artificial disc replacement. It may not be a replacement procedure or alternative to fusion, since recent studies have shown that 100% of fusion patients had one or more contraindications to disc replacement.