Cauda equina compression and acute unilateral foot drop are commonly described associations with prolapsed intervertebral lumbar disc. The bilateral acute foot drop however is a rare occurrence. A 45-year-old adult male labourer presented with 1 month history of low backache, with acute exacerbation 1 day later. He developed acute bilateral foot drop and urinary retention within 2 hours. An urgent magnetic resonance imaging (MRI) revealed large central disc prolapse at L3-L4 level with significant canal stenosis. He was operated on emergent basis following which he had progressive neurological improvement.

The diagnostic criteria, natural history, nerve conduction characteristics, pathology, laboratory features, and efficacy of corticosteroid treatment have been evaluated personally in 53 patients with chronic inflammatory polyradiculoneuropathy (CIP) who were followed up for an average of about 7.5 years. These were patients whose monophasic neurologic deficit had not crested by 6 months, patients with recurrences, and patients with a steady or stepwise progression. The typical features of CIP include absence of an associated disease, frequent history of preceding infection or receipt of foreign protein, and tendency to involve cranial, truncal, and proximal as well as distal limb structures and to have diffusely slow conduction velocity of peripheral nerves. The most marked slowing is often very proximal. The pathologic features include serous edema, mononuclear cell infiltrates (especially in perivascular areas, but without evidence of vasculitis), macrophage-induced segmental demyelination, and hypertrophic neuritis. If our patients are representative, complete recovery occurs only infrequently; about 60% of patients are able to be ambulatory and work, 25% become confined to a wheelchair or become bedridden, and approximately 10% die from their disease. Although the bulk of the pathologic changes affect spinal roots and proximal nerves, the brain and spinal cord may be involved also. Degeneration into linear rows of myelin ovoids is the predominant type of myelinated fiber degeneration of the sural nerve at the ankle.

BACKGROUND Central neuraxial blockades find widespread applications. Severe complications are believed to be extremely rare, but the incidence is probably underestimated. METHODS A retrospective study of severe neurologic complications after central neuraxial blockades in Sweden 1990-1999 was performed. Information was obtained from a postal survey and administrative files in the health care system. During the study period approximately 1,260,000 spinal blockades and 450,000 epidural blockades were administered, including 200,000 epidural blockades for pain relief in labor. RESULTS : The 127 complications found included spinal hematoma (33), cauda equina syndrome (32), meningitis (29), epidural abscess (13), and miscellaneous (20). Permanent neurologic damage was observed in 85 patients. Incidence of complications after spinal blockade was within 1:20-30,000 in all patient groups. Incidence after obstetric epidural blockade was 1:25,000; in the remaining patients it was 1:3600 (P < 0.0001). Spinal hematoma after obstetric epidural blockade carried the incidence 1:200,000, significantly lower than the incidence 1:3,600 females subject to knee arthroplasty (P < 0.0001). CONCLUSIONS : More complications than expected were found, probably as a result of the comprehensive study design. Half of the complications were retrieved exclusively from administrative files. Complications occur significantly more often after epidural blockade than after spinal blockade, and the complications are different. Obstetric patients carry significantly lower incidence of complications. Osteoporosis is proposed as a previously neglected risk factor. Close surveillance after central neuraxial blockade is mandatory for safe practice.

Infectious mononucleosis has been associated with Guillain--Barré syndrome, Bell's palsy, meningoencephalitis and transverse myelitis. Since it is not known that many children with infectious mononucleosis do not develop heterophil antibodies, we looked for evidence of current or recent Epstein-Barr virus infection in young patients with these neurologic diseases by using serodiagnostic procedures for detection and titration of antibodies to various antigens related to Epstein-Barr virus. Seven of 24 cases with Guillain-Barre syndrome and three of 16 with facial palsy were definitely associated with primary infection with Epstein-Barr virus as were two cases each of the other two neurologic diseases. Only one of these patients had obvious clinical infectious mononucleosis, and only a few demonstrated heterophil agglutinins. It is evident that the virus must be considered in the diagnosis of various acute neurologic diseases affecting children and young adults, even in the absence of heterophil-antibody response or other signs of infectious mononucleosis.

We studied three patients with acquired immune deficiency syndrome (AIDS) and progressive polyradiculopathy. Postmortem examination of one patient disclosed extensive necrosis, inflammatory infiltrates, and focal vasculitis of spinal roots. Typical cytomegaloviral (CMV), intranuclear, and intracytoplasmic inclusions were noted within enlarged endoneurial and endothelial cells. Progressive polyradiculopathy is an unusual complication of AIDS; CMV may be the causative agent in certain cases.

OBJECT The authors report a retrospective analysis of 194 patients surgically treated at their institutions for symptomatic lumbar synovial cysts from January 1974 to January 1996. METHODS Patient characteristics including age, sex, symptoms, signs, and preoperative neuroimaging studies were reviewed. Surgical procedures, complications, results, and pathological findings were correlated with preoperative assessment. One hundred ninety-four patients were surgically treated for symptomatic lumbar synovial cysts. Eighty percent were diagnosed and treated between 1987 and 1996. There were 100 men and 94 women with an average age of 66 years (range 28-94 years). The most common symptoms were painful radiculopathy (85%) and neurogenic single or multiroot claudication (44%). However, sensory loss (43%) and motor weakness (27%) were also presenting symptoms. Eleven percent of patients had undergone previous lumbar surgery prior to being referred to the Mayo Clinic. Preoperative neurological examination demonstrated motor weakness (40%), sensory loss (45%), reflex changes (57%), and variants of cauda equina syndrome (13%). In 19% of patients, normal neurological status was demonstrated. There was equal left/right-sided laterality, and eight patients presented with bilateral synovial cysts. The most commonly affected level was L4-5 (64%). All patients underwent laminectomy and resection of the cyst. Concomitant fusion was performed in 18 patients in whom clinical evidence of instability had been observed. However, subsequent fusion was required in only four patients who developed symptomatic spondylolisthesis. Surgery-related complications included cerebrospinal fluid leak (three patients), discitis (one patient), epidural hematoma (one patient), seroma (one patient), and deep vein thrombosis (one patient). One patient died 3 days after surgery of cardiac dysrhythmia. Follow-up data obtained for at least 6 months postoperatively were available in 147 patients. Of these, 134 (91%) reported good relief of their pain and 82% experienced improvement in their motor deficits. CONCLUSIONS Lumbar synovial cysts are a more common cause of lumbar radicular pain than previously thought. Surgical removal of the cyst is a safe and effective treatment for symptomatic relief in patients with lumbar synovial cysts. A concomitant fusion procedure may be performed in select cases. In this study, only a few patients developed symptomatic spinal instability requiring a second operation.

After 43 years of investigating the intervertebral disk, the long term results of the management of patients from the standpoint of pain are not significantly different than they were prior to the identification of the herniated disk nor do they seem to be significantly different than no treatment at all. This should at least suggest that the phenomena of low back pain is far more complex than can be accounted for on the basis of a simple mechanical-pressure theory of disk derangement. There is a significant volume of literature that would point to the neural tissues themselves as the most logical structures for future research that attempts to interfere with the natural history of this disease from the standpoint of pain. It seems most appropriate to attack lumbar disk disease from this standpoint because except in uncommon cases, the pathological process is benign and self limiting. It also seems logical that major advancements in the management of "diskogenic" back pain will depend upon an appreciation of the importance of controlling neural inflammation in the early phases of the disease rather than developing new techniques of managing irreversible neural lesions and their iatrogenetic or psychiatric sequelae.