Lumbar discography: a comprehensive review of outcome studies, diagnostic accuracy, and principles.

BACKGROUND AND OBJECTIVES: Since its advent more than 50 years ago, the use of discography has been mired in controversy. The purpose of this review is to provide a clinical overview of lumbar discography and discogenic back pain, with special emphasis on determining the accuracy of discography and whether or not the procedure improves outcomes for surgery. METHODS: Material for this review was obtained from a MEDLINE search conducted from 1951 thru September 2004, bibliographic references, book chapters, and conference proceedings. RESULTS: Based on a large number of comparative studies, plain discography is less accurate than magnetic resonance imaging in diagnosing lumbar herniated nucleus pulposus and comparable or slightly more sensitive in detecting degenerative disc disease. For disc degeneration, CT discography remains the gold standard for diagnosis. There are very few studies comparing surgical outcomes between patients who have undergone preoperative provocative discography and those who have not. What little evidence exists is conflicting. Before disc replacement surgery, approximately half the studies have used preoperative discography. A comparison of outcomes did not reveal any significant difference between the 2 groups but none of the studies was controlled, and they used different outcome measures, follow-up periods, and surgical techniques. Because all intradiscal electrothermal therapy (IDET) studies have used discography before surgery, no conclusions can be drawn regarding its effects on outcome. CONCLUSIONS: Although discography, especially combined with CT scanning, may be more accurate than other radiologic studies in detecting degenerative disc disease, its ability to improve surgical outcomes has yet to be proven. In the United States and Europe, there are inconsistencies in the use of lumbar discography such that it is routinely used before IDET, yet only occasionally used before spinal fusion.

Spinal cord stimulation for treatment of meralgia paresthetica.

BACKGROUND: Meralgia paresthetica is a clinical syndrome of pain, dysesthesia or both, in the anterolateral thigh. It is associated with an entrapment mononeuropathy of the lateral femoral cutaneous nerve. Diagnosis of meralgia paresthetica is typically made clinically and is based on the characteristic location of pain or dysesthesia, sensory abnormality on exam, and absence of any other neurological abnormality in the leg. The majority of patients with meralgia paresthetica respond well to conservative treatment. OBJECTIVE: To present a case of intractable meralgia paresthetica in which conservative treatment options failed but which was successfully treated with a spinal cord stimulator. CASE REPORT: A 44-year-old woman presented to the pain clinic with a one-year history of bilateral anterolateral thigh pain. History, physical exam, and diagnostic work-up were consistent with meralgia paresthetica. Multiple medications, physical therapy, and chiropractic therapy were not successful for this patient. In addition, local anesthetic/steroid injection of the lateral femoral cutaneous nerve provided only short-term relief. Ultimately, a spinal cord stimulator was implanted after a successful temporary percutaneous trial. Two months after the implantation, she continued to have 100% pain relief, worked full-time, was physically active, and no longer required any pain medication including opioids. CONCLUSION: An implanted spinal cord stimulator may be an ideal treatment for intractable meralgia paresthetica after conservative treatments have failed because it is not destructive and can always be explanted without significant permanent adverse effects.

Perioperative immunosuppression in cancer patients.

Cancer patients commonly undergo surgical procedures. The perioperative period is characterized by immunosuppression and may predispose already immunosupressed cancer patients to tumor spread. Cancer patients typically show depression of both cellular and humoral immune functions. Possible mediating factors for immunosuppression during the perioperative period include anesthetic agents, opioids, surgery, blood transfusions, temperature changes, pain, and psychological stress. A surgically mediated decrease in natural killer (NK) cell activity has been implicated as the major contributing factor associated with an increase in metastasis. The decreased NK cell activity during the perioperative period is associated with increased risk of mortality and cancer. Commonly used anesthetic agents and opioids are known to inhibit NK cell activity. Despite the in vivo evidence of anesthetic- and analgesic-agent-mediated immunosupression, surgery by itself results in a three- to four-fold increase in retention of metastasis when compared to the groups in which anesthesia and analgesia were combined. The negative consequences associated with perioperative immunosuppression may be decreased by several strategies, including aggressive pain control, selection of specific anesthetic and analgesic agents, avoidance of unnecessary transfusions, and delay of elective surgeries until the patient's nutritional and immune status is optimized. Recognizing and neutralizing its mediating factors, perioperative immunosuppression in cancer patients may be reduced.