Low back pain, together woth shoulder and neck pain, affect millions of individuals, and is a very usual topic of concern. Frequently is associated with sciatica. Two different low back pain groups are reported: 1--Unspecific low back pain; 2--Organic low bck pain. Unspecific low back pain: two considerations must be present: a) Absence of clinical or radiological signs of concrete disease, and b) Presence of a psychological profile defined by a personality unable to live together with pain. Different pathogenic mechanisms have been invoked to explain the unspecific low back pain: disc herniation irritating the posterior disc ring and the common posterior vertebral ligament, arthritis of small and real--have synovial--, interapophyseal joints, trigger zones of local spasm in the spinal muscles, postural changes after having remained a long time in the same position, and for some few ones, ligament instability in the sacroiliac joint. Organic low back pain: characterized like congenital diseases, acquired diseases--discal herniation, spondylosis, lumbar spine stenosis--, And systemic diseases affecting the spine: aortoiliac chronic vascular disease and abdominal processes causing lumbar and buttocks pain. The therapeutic alternative is either conservative or surgical. Surgery is protagonist in post-traumatic unstale spine, in unstable spondylolisthesis, in spine persistent infections and in spine tumours. Also is subsidiary of surgical treatment the disc degeneration with nerve root irritation causing motor disturbance. The disc degeneration without root irritation precludes conservative management: percutaneous manual nucleotomy, coblation nucleoplasty or back schools programmes, defined like interventions consisting of education and skill programmes supervised by a physical therapist trained in back rehabilitation.

BACKGROUND: Although epidural corticosteroid injections are commonly used for sciatica, their efficacy has not been established. METHODS: In a randomized, double-blind trial, we administered up to three epidural injections of methylprednisolone acetate (80 mg in 8 ml of isotonic saline) or isotonic saline (1 ml) to 158 patients with sciatica due to a herniated nucleus pulposus. All patients had Oswestry disability scores higher than 20 (on a scale of 1 to 100, with scores of 20 or less indicating minimal disability, and higher scores greater disability). RESULTS: At three weeks, the Oswestry score had improved by a mean of -8.0 in the methylprednisolone group and -5.5 in the placebo group (95 percent confidence interval for the difference,-7.1 to 2.2). Differences in improvements between the groups were not significant, except for improvements in the finger-to-floor distance (P=0.006) and sensory deficits (P=0.03), which were greater in the methylprednisolone group. After six weeks, the only significant difference was the improvement in leg pain, which was greater in the methylprednisolone group (P=0.03). After three months, there were no significant differences between the groups. The Oswestry score had improved by a mean of -17.3 in the methylprednisolone group and -15.4 in the placebo group (95 percent confidence interval for the difference,-9.3 to 5.4). At 12 months, the cumulative probability of back surgery was 25.8 percent in the methylprednisolone group and 24.8 percent in the placebo group (P=0.90). CONCLUSIONS: Although epidural injections of methylprednisolone may afford short-term improvement in leg pain and sensory deficits in patients with sciatica due to a herniated nucleus pulposus, this treatment offers no significant functional benefit, nor does it reduce the need for surgery.

The purpose of this study was to assess the natural history of sciatica due to lumbosacral nerve root compromise and to evaluate the pathomorphologic changes that accompany the natural resolution of the disease. One hundred sixty-five consecutive patients, 114 males and 51 females, with an average age of 41 years (range, 17-72) and an average duration of symptoms of 4.2 months (range, 1-72) presenting with sciatica thought to be due to lumbosacral nerve root compromise were admitted to the study. The cornerstone of treatment was the serial epidural administration of steroid and local anesthetic by the caudal route on an outpatient basis. Lumbar epidural injection or periradicular infiltration at the appropriate level, confirmed under image intensifier, was the next step before considering surgical decompression. An average of three injections (range, 0-8) was received by each patient. Patients underwent clinical examination and computed tomography. Twenty-three patients (14%) underwent surgical decompression. The remainder were clinically assessed at 1 year after presentation, and 111 were rescanned at the appropriate levels. All conservatively managed patients made a satisfactory clinical recovery: average reduction of pain on the visual analog scale was 94%(range, 45-100), and 64 (76%) of the 84 disc herniations and 7 (26%) of the 27 disc bulges showed partial or complete resolution (chi-square = 20.27, P = 0.0001). Thus a high proportion of patients with discogenic sciatica make a satisfactory recovery with aggressive conservative management, and this recovery is accompanied by resolution of disc herniations in a significant number. Only a small proportion of patients needed surgical decompression.

Seventy-three patients with lumbar radicular pain syndromes were treated in a prospective, randomized, double-blind fashion with either seven milliliters of methylprednisolone acetate and procaine or seven milliliters of physiological saline solution and procaine. All patients had radiographic confirmation of lumbar nerve-root compression, consistent with the clinical diagnosis of either an acute herniated nucleus pulposus or spinal stenosis. No statistically significant difference was observed between the control and experimental patients with either acute disc herniation or spinal stenosis. Long-term follow-up, averaging twenty months, failed to demonstrate the efficacy of a second injection of epidural steroids administered to the patients whose pain did not respond within twenty-four hours to an injection of either eighty milligrams of methylprednisolone acetate combined with five milliliters of 1 per cent procaine or two milliliters of sterile saline combined with five milliliters of 1 per cent procaine. Therefore, a decision to use epidural steroids must be made with the realization that we failed to demonstrate its clinical efficacy in this study and that reports of serious complications of this procedure have been published.

The basic pathophysiologic mechanisms related to disc herniation and sciatica are poorly understood. Recently it was demonstrated that nucleus pulposus from an intervertebral disc could induce structural and functional changes in adjacent nerve roots when applied epidurally, however, it is not known if such changes are painful. In a model for inducing disc herniation in the rat, we found that puncture of a lumbar disc with subsequent herniation of nucleus pulposus without nerve root compression, or chronic displacement of the 4th lumbar nerve root and ganglion, did not individually induce significant changes in thresholds for mechanical or thermal stimulation compared to sham-operated animals. However, the combination of disc puncture and displacement induced a reduction of the threshold for thermal stimulation, indicating hyperalgesia, that was present 2 days after surgery and gradually recovered during a 14-day period. These data and the associated description of this new model for experimental disc herniation may increase our understanding of the pathophysiologic events leading to sciatica and help in evaluating new modalities for diagnosis and treatment of disc herniation and sciatica.

PURPOSE: To review evidence on the diagnostic accuracy of clinical information and imaging for patients with low back pain in primary care settings. DATA SOURCE: MEDLINE search (January 1966 to September 2001) for articles and reviews relevant to the accuracy of the clinical and radiographic examination of patients with low back pain. STUDY SELECTION: The authors reviewed abstracts and selected articles for review on the basis of a combined judgment. Data on the clinical examination were based primarily on recent systematic reviews; data on imaging tests were based primarily on original articles. DATA EXTRACTION: Diagnostic results were extracted by one or the other author. Quality of methods was evaluated informally. Major potential biases were identified, but neither quantitative data extraction nor scoring was done. DATA SYNTHESIS: Formal meta-analysis was not used because the diagnostic hardware and software, gold standards, and patient selection methods were heterogeneous and the number of studies was small. Sensitivity for cancer was highest for magnetic resonance imaging (0.83 to 0.93) and radionuclide scanning (0.74 to 0.98); specificity was highest for magnetic resonance imaging (0.9 to 0.97) and radiography (0.95 to 0.99). Magnetic resonance imaging was the most sensitive (0.96) and specific (0.92) test for infection. The sensitivity and specificity of magnetic resonance imaging for herniated discs were slightly higher than those for computed tomography but very similar for the diagnosis of spinal stenosis. CONCLUSIONS: The data suggest a diagnostic strategy similar to the 1994 Agency for Health Care Policy and Research guidelines. For adults younger than 50 years of age with no signs or symptoms of systemic disease, symptomatic therapy without imaging is appropriate. For patients 50 years of age and older or those whose findings suggest systemic disease, plain radiography and simple laboratory tests can almost completely rule out underlying systemic diseases. Advanced imaging should be reserved for patients who are considering surgery or those in whom systemic disease is strongly suspected.

Sixty patients with unilateral sciatica resulting from lumbar intervertebral disc herniation were entered into a double-blind study. All patients had failed to respond to conservative management, and the diagnosis had been confirmed by metrizamide myelography. Following a randomized schedule, 30 patients had intradiscal injections of chymopapain, and 30 patients had intradiscal injections of an equivalent volume of normal saline solution. Two years after the injection, 77% of patients treated with chymopapain were assessed as moderately improved, compared with 47% of saline-injected patients. Fifty-seven percent of the chymopapain group were free of pain, compared with 23% in the saline group. Based on the late results of this study, chymopapain is recommended for the treatment of sciatica from intervertebral disc herniation when conservative measures have failed and before disc fragment excision is considered.

Galanin is a 29-aa neuropeptide with a complex role in pain processing. Several galanin receptor subtypes are present in dorsal root ganglia and spinal cord with a differential distribution. Here, we describe a generation of a specific galanin R2 (GalR2) agonist, AR-M1896, and its application in studies of a rat neuropathic pain model (Bennett). The results show that in normal rats mechanical and cold allodynia of the hindpaw are induced after intrathecal infusion of low-dose galanin (25 ng per 0.5 microl/h). The same effect is seen with equimolar doses of AR-M1896 or AR-M961, an agonist both at GalR1 and GalR2 receptors. In allodynic Bennett model rats, the mechanical threshold increased dose-dependently after intrathecal injection of a high dose of AR-M961, whereas no effect was observed in the control or AR-M1896 group. No effect of either of the two compounds was observed in nonallodynic Bennett model rats. These data indicate that a low dose of galanin has a nociceptive role at the spinal cord level mediated by GalR2 receptors, whereas the antiallodynic effect of high-dose galanin on neuropathic pain is mediated by the GalR1 receptors. Thus, a selective GalR1 agonist may be used to treat neuropathic pain.

STUDY DESIGN. Historical cohort, including selected subgroups. OBJECTIVES. To understand the long-term effects of exercise on back-related outcomes, back pain, sciatica, back-related hospitalizations, pensions, and magnetic resonance imaging findings were studied among former elite athletes. SUMMARY OF BACKGROUND DATA. Exercise and sports participation have become increasingly popular, as have recommendations of exercises for back problems, but little is known about their long-term effects. METHODS. Questionnaires were returned by 937 former elite athletes and 620 control subjects (83% response rate). Identification codes allowed record linkage to hospital discharge and pension registers. Magnetic resonance images were obtained of selected subgroups with contrasting physical loading patterns. RESULTS. Odds ratios for back pain were lower among athletes than among control subjects, with significant differences in endurance, sprinting and game sports, and wrestling and boxing. No differences in the occurrence of sciatica or in back-related pensions and hospitalizations were seen. When comparing lumbar magnetic resonance images of 24 runners, 26 soccer players, 19 weight lifters, and 25 shooters, disc degeneration and bulging were most common among weight lifters; soccer players had similar changes in the L4-S1 discs. No significant differences were seen in the magnetic resonance images of runners and shooters. CONCLUSIONS. Maximal weight lifting was associated with greater degeneration throughout the entire lumbar spine, and soccer with degeneration in the lower lumbar region. No signs of accelerated disc degeneration were found in competitive runners. However, back pain was less common among athletes than control subjects and there were no significant differences in hospitalizations or pensions. No benefits were shown for vigorous exercise compared with lighter exercise with respect to back findings.