Eur J Pharmacol 2001 Sep 7;427(1):27-35
Department of Functional Restoration, Stanford University School of Medicine, Stanford, CA, USA. wkingery@stanford.edu
In previous studies using Fos expression as a marker of neuronal activation, we showed that nitrous oxide (N(2)O) activates bulbospinal noradrenergic neurons in rats and that destruction of these neuronal pathways leads to loss of N(2)O antinociceptive action. Based on previous rat studies it has been proposed that these noradrenergic neurons are activated through opioid receptors through the release of endogenous opioid ligands in the periaqueductal gray. Using mice with a disrupted preproenkephalin gene (Penk2 -/-) and the opioid receptor antagonist naltrexone, we investigated the role of enkephalinergic mechanisms and opioid receptor activation in the behavioral and bulbospinal neuron responses to N(2)O in mice. The antinociceptive response to N(2)O was investigated using the tail-flick, hot-plate, and von Frey assays, the sedative/hypnotic response was measured using rotarod and loss of righting reflex, and bulbospinal neuronal activation was assessed with pontine Fos immunostaining. No differences were observed between wild-type and Penk2 -/- mice for the antinociceptive, sedative/hypnotic, and pontine neuronal activation effects of N(2)O. Similarly, naltrexone did not block N(2)O-induced antinociception, sedation, or hypnosis. We conclude that neither enkephalin nor opioid receptors participate in either the antinociceptive or the sedative/hypnotic actions of N(2)O in mice.
PMID: 11553360, UI: 21437581
Order this document
Geriatrics 2001 Oct;56(10):14-7, 20-2, 24
Pain Services, Kaiser Permanente, Department of Family Practice, University of California, San Diego, USA.
Osteoarthritis (OA) typically affects persons over age 60 and is often associated with pain and disability. Weight-bearing joints are most commonly affected. The goal of treatment is to minimize pain and its impact on patient function and quality of life. Patient education, psychological support, weight control, exercise, heat/cold application, and use of assistive devices are safe nonpharmacologic approaches. Pharmacologic therapies include acetaminophen, selected NSAIDs, and other analgesics, including opioids for moderate to severe pain. Topical agents, complementary products, viscosupplementation, and surgery may be useful in an individualized treatment plan.
Publication Types:
PMID: 11641858, UI: 21520433
Lancet 2001 Oct 6;358(9288):1182-3
PMID: 11597704, UI: 21482454
Spine 2001 Nov 1;26(21):2375-80
Department of Orthopedics, Lund University Hospital, Lund, Sweden.
[Medline record in process]
STUDY DESIGN: A prospective observational study of visual analog scale (VAS) scores for pain in patients operated at one institution within the framework of a national registry. OBJECTIVE: To describe the use of recording VAS for pain intensity in patients operated on for lumbar spine problems. SUMMARY OF BACKGROUND DATA: There is no consensus regarding pain outcomes assessment in spine patients. Pain intensity, recorded on a VAS, is one of the most used measures. Still, many aspects of its interpretation are still debated or unclear. METHODS: A total of 755 consecutive patients, mean age 50 years (range, 15-86 years), operated from 1993 to 1998 were included in the study; there were 420 males and 335 females. Diagnoses included herniated nucleus pulposus (45%), central stenosis (19%), lateral stenosis (14%), isthmic spondylolisthesis (9%), and degenerative disc disease (9%). Local pain, radiating pain, analgesic intake, and walking ability were recorded before surgery and at 4 and 12 months after surgery. The patients' opinions regarding the change in pain and satisfaction with the result were assessed separately. Correlation among variables reflecting perceived pain was sought. RESULTS: Preoperative VAS mean values for local and radiating pain were significantly different in the five diagnostic groups. Significant but moderate correlation between different types of pain outcomes and with patient satisfaction was present in all cases. CONCLUSIONS: Measuring pain intensity with VAS is a useful tool in describing spine patients. In the search for a standard in the evaluation of pain as an outcome, the differences between the various methods should be taken into account.
PMID: 11679824, UI: 21537334
Spine 2001 Nov 1;26(21):2368-74
The Health Institute, Boston, Massachusetts.
STUDY DESIGN: A cross-sectional study. OBJECTIVES: To determine the relative contribution of pain increase and mental health to testing performance during a single bout of exercise in patients with chronic low back pain. BACKGROUND: Controversy exists as to which factors principally limit physical performance in patients with chronic low back pain. Some believe psychological factors limit physical performance, whereas others believe activity-related increases in pain intensity limit performance. METHODS: Seventy-five patients with chronic low back pain reported pain intensity before and after undergoing a maximal, symptom-limited modified treadmill test. Walking time (in minutes) and aerobic fitness were measured. The Short Form 36 Health Survey was administered to all patients. RESULTS: Fifty-four percent of the sample stopped testing because of a significant increase in pain intensity (P = 0.0001). Treadmill performance was lower in patients who stopped because of pain than in those who stopped because of fatigue (P = 0.02). The patients who stopped because of pain were also more likely to have low mental health as assessed by the Short Form 36 Health Survey. Low mental health, however, did not have a statistically significant influence on treadmill performance. CONCLUSION: The data indicate that impairment of physical performance during treadmill testing in patients with chronic low back pain is attributable to testing-induced increase in pain intensity rather than to individual low mental health scores.
PMID: 11679823, UI: 21537333
Spine 2001 Sep 15;26(18):1997-2000
Department of Spine Surgery, Rizzoli Orthopedic Institute, Bologna, Italy. parisini.p@tiscalinet.it
STUDY DESIGN: The authors examined a case series of patients under the age of 18 years treated for lumbar intervertebral disc herniation. OBJECTIVES: To evaluate postoperative and long-term results of surgery in patients younger than 18 years. SUMMARY OF BACKGROUND DATA: There are only a few series, with controversial results, available on the surgical treatment of disc herniation in growing patients. METHODS: Between 1975 and 1991, a consecutive series of 129 patients 9-18 years of age (average age, 16.2 years) underwent surgery for lumbar intervertebral disc herniation. Low back pain associated with leg pain was the main clinical symptom in 106 subjects (82%), back pain in 17 (13%), and leg pain in 6 (5%). RESULTS: Short-term results were excellent or good for 123 cases (95%), with complete pain relief in 97 (75%) and moderate but incomplete relief in 26 (20%). A total of 98 (76%) long-term responses obtained at a mean follow-up of 12.4 years revealed excellent outcomes in 40% of the cases, good in 47%, and poor in 13%. Ten patients (10%) underwent reintervention after 9 years on average (2 fusions and 8 re-explorations for herniated disc). CONCLUSIONS: Results have confirmed a tendency for outcomes to deteriorate between the short-term and long-term follow-up in young patients treated by discectomy: this tendency and the rate of reintervention (10%) confirmed the need for long-term follow-up of children and adolescents treated for disc herniation.
PMID: 11547199, UI: 21432203
the above reports in Macintosh PC UNIX Text HTML format documents on this page through Loansome Doc