bluuebunny/crossref_metadata_2025_split huggingface dataset:
Basic Science (29)
Authors: Pogatzki Esther M. , Zahn Peter K. , Brennan Timothy J. 
Published: September 2010

Effect of pretreatment with intrathecal excitatory amino acid receptor antagonists on the development of pain behavior caused by plantar incision. (University of Iowa, Iowa City, Iowa) Anesthesiology 2000;93:489–496.This study examined the role of N‐methyl‐D‐aspartate (NMDA), non‐NMDA, and metabotropic glutamate receptors (MGluRs) on the development of pain behavior after plantar incision. Rats with lumbar intrathecal catheters were anesthetized with halothane. Fifteen minutes before an incision was made, drug [40 nmol MK‐801; 20 nmol NBQX; or 200 nmol [(+)‐MCPG] or vehicle was injected intrathecally followed by an infusion of the same drug for 75 min. Withdrawal thresholds to calibrated von Frey filaments applied adjacent to the wound and response frequencies to a blunt mechanical stimulus applied directly to the wound were measured before incision and 1, 2, 4, and 6 h after incision and then once daily for 6 days. Preincision treatments with antagonists against the NMDA (MK‐801) and Group I and II metabotropic receptors [(+)‐MCPG] did not inhibit the development of mechanical hyperalgesia caused by incision. Preincision treatment with the non‐NMDA receptor antagonist NBQX increased withdrawal thresholds at 1 and 2 h and on postoperative day 1 compared with the vehicle group; response frequencies were reduced 1 and 2 h after incision and on postoperative day 2 (P < 0.05). In an additional group, postincision treatment with NBQX was similar to preincision treatment. Conclude spinal NMDA and MGluR antagonists may not be useful for preventing postsurgical pain. Spinal non‐NMDA receptor antagonists reduced pain behaviors, but a preventive effect using preincision treatment was not apparent. Comment by James E. Heavner, DVM, PhD.The incisional model using rats was developed by Dr. Brennan and colleagues for the study of acute surgical pain. In a previous study, they showed that blockade of non‐NMDA excitatory amino acid receptors, but not blockade of NMDA receptors nor mGluR receptors reduces postincisional pain if administered after the incision is made. This study shows the same is true if the receptor antagonists are administered before the incision is made. However, the effect is not particularly marked and; therefore, pursuit of non‐MNDA excitatory amino transmitter receptor blockers for the prevention of postincisional pain would not likely be fruitful. The results of the study do require us to rethink how postincisional pain differs from other experimental pains and the phenomena of “wind‐up” attributed to activation of the NMDA receptor. Worth keeping in mind is that incisional pain does not equal surgical pain, which may involve traumatic injury to nerves and produce a neuropath pain, which strongly indicates involvement of NMDA receptors.
Anesthesia (3)
Authors: Burm Anton G.L. , Stienstra Rudolf , Brouwer Rolf P. , Emanuelsson Britt‐Marie , Van Kleef Jack W. 
Published: September 2010

Epidural infusion of ropivacaine for postoperative analgesia after major orthopedic surgery. (Leiden University Medical Center, Leiden, The Netherlands) Anesthesiology 2000;93:395–403.This study evaluated the pharmacokinetics of ropivacaine administered by 72‐h epidural infusion to provide postoperative analgesia. Twenty‐eight patients scheduled for major orthopedic surgery during combined epidural and general anesthesia received a bolus dose of ropivacaine (50 or 70 mg), followed by constant‐rate (10 mL/h) epidural infusion of ropivacaine 2 mg/mL (Group 1) or 3 mg/mL (Group 2). Total and unbound plasma concentrations of ropivacaine and pipecoloxylidide and plasma concentrations of α1‐acid glycoprotein were determined. The urinary excretion of ropivacaine and major metabolites was measured. Results showed that total plasma concentrations of ropivacaine increased steadily during infusion and unbound ropivacaine concentrations reached average steady levels of approximately 0.06 and 0.07 mg/l. Total and unbound concentrations of pipecoloxylidide increased to 1.0 ± 0.4 and 0.4 ± 0.2 mg/l (Group 1) and 1.2 ± 0.4 and 0.5 ± 0.1 mg/l (Group 2) after 72 h infusion. α1‐Acid glycoprotein concentrations initially decreased, but thereafter increased steadily to approximately twice the baseline values. Conclude postoperative increases in plasma α1‐acid glycoprotein concentrations enhance the protein binding of ropivacaine and pipecoloxylidide, which causes divergence of total and unbound plasma concentrations.
Basic Science (31)
Authors: Boucher Timothy J. , Okuse Kenji , Bennett David L.H. , Munson John B. , Wood John N. , McMahon Stephen B. 
Published: September 2010

Potent analgesic effects of GDNF in neuropathic pain states. (King's College London, London, United Kingdom) Science 2000;290:124–127.Neuropathic pain arises as a debilitating consequence of nerve injury. The etiology of such pain is poorly understood, and existing treatment is largely ineffective. We demonstrate here that glial cell line‐derived neurotrophic factor (GDNF) both prevented and reversed sensory abnormalities that developed in neuropathic pain models, without affecting pain‐related behavior in normal animals. GDNF reduces ectopic discharges within sensory neurons after nerve injury. This may arise as a consequence of the reversal by GDNF of the injury‐induced plasticity of several sodium channel subunits. Together these findings provide a rational basis for the use of GDNF as a therapeutic treatment for neuropathic pain states. Comment by Marshall Devor, PhD.Nerve injury frequently causes sensory neurons to become electrically hyperexcitable. The resulting ectopic afferent firing is thought to be the immediate cause of ongoing pain, movement‐evoked pain, and allodynia in neuropathic pain states. But why do the neurons become hyperexcitable? A popular hypothesis has it that when the axon is cut, the sensory cell body in the dorsal root ganglion (DRG) is starved of essential neurotrophic molecules that are normally produced in the periphery and transported to the DRG via axoplasmic transport. If so, then providing an exogenous source of the critical neurotrophin should prevent, or even reverse, the hyperexcitability and the pain. Boucher et al tried this, administering 1 of 3 candidate neurotrophins (NGF, NT‐3, or GDNF) by the intrathecal (i.t.) route. One of them, GDNF, worked dramatically. The authors believe that i.t. GDNF acts by diffusing into the DRG (rather than the spinal cord) where it alters the expression of the channel proteins that are responsible for electrical hyperexcitability.
Clinical Science (36)
Authors: Greipp Mary E. 
Published: September 2010

A follow‐up study of 14 young adults with complex regional pain syndrome type I. (Hospital Morvan, Brest, France) J Neurosci Nurs. 2000;32:83–88.This study evaluated the symptom experience and functional status of 27 young adults with reflex sympathetic dystrophy syndrome, now known as complex regional pain syndrome (CRPS) type I. All were originally diagnosed and studied 12 years ago. Only 15 subjects could be located; 14 participated in the research. A descriptive exploratory design was utilized. A tool was designed to gather data about daily living variables, psychological variables, and symptom variables. Although many questions required the use of Likert scales, there were some open‐ended questions to capture the qualitative descriptions of the participant's symptom experiences. Findings contribute to the clinical literature about CRPS and its effect on clients over time. Comment by Mauricio Orbegozo, MD.This paper is a follow‐up interview on 14 patients diagnosed with complex regional pain syndrome (CRPS) type I more than a decade ago. The author created a tool with the purpose of gathering data in 3 different aspects such as: current activity levels, psychosocial assessment, and symptom experiences. This data were gathered in a questionnaire form. The first 2 sections (current acting levels and psychosocial assessment) are questions to be answered on a 4‐point Likert scale and the last part (symptom experiences) is an open‐ended question section where the subject can answer in a more descriptive manner. What is particular about the population of patients in this study is the fact that all were diagnosed at an early age (childhood or as young adults). This yielded an interesting set of results. As far as current activity levels, more that two‐thirds of the patients were able to perform basic daily living activities and at least 50% of them can perform more strenuous activities such as running, climbing stairs, and driving a car. The results above extrapolate well into the psychosocial assessment where greater than 90% considered themselves self‐sufficient. Of interest was the fact that there was no depression or overwhelming psychiatric morbidity reported. This could be because at a younger age of onset for CRPS type I, more effective coping skills can be developed that would aid these patients in adaptation to daily life. It is not surprising that in symptom experience the most common was continuing pain, followed by limitations in range of motion. In summation, this study sheds light into an aspect that has not been researched in an extensive manner, which is a long‐term follow‐up of patients suffering from CRPS type I and how they adapted to daily life. Although conclusions reflect valid facts, the sample size is small and larger population including patients who develop CRPS type I at later stages in life may provide us with crucial information in a general set of patients.
Clinical Science (37)
Authors: Kemler Marius A. , Barendse Gerard A.M. , Van Kleef Maarten , Egbrink Mirjam G.A. Oude 
Published: September 2010

Pain relief in complex regional pain syndrome due to spinal cord stimulation does not depend on vasodilation. (Maastricht University Hospital, Maastricht, The Netherlands) Anesthesiology 2000;92:1653–1660.This study aimed to assess whether pain relief in complex regional pain syndrome (CRPS after spinal cord stimulation (SCS) is, in fact, dependent on vasodilation. In addition, the study attempted to determine which of the potential mechanisms may cause the vasodilatory effect that is generally found after SCS. Twenty‐four of 36 patients with unilateral CRPS responded to the test of SCS. Twenty‐two of the 24 responders (hand, n = 14; foot, n = 8) who had undergone previous sympathectomy were enrolled in the study. In addition, 20 control subjects (10 controls for each extremity) were studied. By means of laser Doppler flowmetry, the skin microcirculation of the patients was measured bilaterally while the SCS system was switched off and while it was activated. Control subjects were tested only once. The ratio of the rest flow at heart level and the dependent position was defined as the vasoconstricted index. Both in affected hands and feet, patients were found to have lower vasoconstriction indices (P < 0.01) as compared with controls, indicating a decreased sympathetic tone. Applying SCS did not result in any microcirculatory change as compared with the baseline or the contralateral clinically unaffected side. Conclude that the study failed to show that SCS influences skin microcirculation in patients with CRPS and a low sympathetic tone. Therefore, it was also concluded that pain relief in CRPS due to SCS is possible without vasodilation. Because sympathetic activity was greatly decreased in the patients, these results support the hypothesis that the vasodilation that is normally found with SCS is due to an inhibitory effect on sympathetically maintained vasoconstriction. Comment by Hemmo A. Bosscher, MD.SCS probably provides pain relief independent of increases in blood flow to the affected area. There may be several weaknesses in this study. All patients underwent prior sympathectomy. As every pain management specialist knows, the results of these procedures are variable. That leaves a group of pain patients with CRPS I that is either predominantly sympathetically mediated or sympathetically independent, with variable degrees of sympathetic blockade. In addition, only part of the peripheral circulation is measured with a device which accuracy has not yet been confirmed. Many variables are introduced in this study making a statement that there are no differences between the treatment group and the control somewhat strong. In my opinion: pain relief in complex regional pain syndrome due to spinal cord stimulation may not depend on vasodilatation.
Clinical Science (38)
Authors: Lillesø J. , Hammer N.A. , Pedersen J.L. , Kehlet H. 
Published: September 2010

Effect of peripheral morphine in a human model of acute inflammatory pain. (Hvidovre University Hospital, Hvidovre, Denmark) BR J Anaesth 2000;85:228–232.This study used a randomized, double‐blinded, placebo‐controlled, three‐way crossover design in a human model of acute inflammatory pain (heat injury). Eighteen healthy volunteers were studied who each received morphine locally (2 mg), morphine systemically (2 mg), or placebo on three separate study days. The subjects received morphine infiltration subcutaneously (s.c.) 1 h before heat injury (47°C, 7 min) and naloxone infiltration s.c. (0.2 mg) 2.5 h after the heat injury. Hyperalgesia to mechanical and heat stimuli were examined using von Frey hairs and thermodes, and pain was rated using a visual analogue scale. The burns produced significant hyperalgesia, but local morphine infiltration neither reduced pain during the burn, nor primary or secondary hyperalgesia to mechanical and heat stimuli after the burn. Conclude peripherally applied morphine had no acute antinociceptive effects in this human model of acute inflammatory pain. Comment by Hemmo A. Bosscher, MD.This study is well controlled for placebo effect and the systemic effect of subcutanuously injected morphine. One of the few criticisms that can be made is the amount of narcotic injected. This may not be enough to bind to a sufficient number of receptors. One would expect some role for peripheral opioid receptors. The other comment would be that this type of injury (mainly small fiber involvement in this case) does not represent all types of nociception and, therefore, the peripheral action of morphine can not be excluded for different types of nociception. But overall this is a convincing study, consistent with the literature.
Clinical Science (39)
Authors: Lewis M.C. , Lafferty J.P. , Sacks M.S. , Pallares V.S. , TerRiet M. 
Published: September 2010

How much work is required to puncture dura with Tuohy needles? (Veterans Affairs Medical Center/Jackson Memorial Medical Center, University of Miami, Miami, FL) BR J Anaesth 2000;85:238–241.This study was designed to evaluate whether bevel orientation or patient position alters the force necessary to produce dural puncture. A constant hydrostatic pressure was applied to the subdural surface, either high or low, simulating the sitting and lateral positions. A 17‐gauge Tuohy needle was advanced through the dura with the bevel oriented parallel or perpendicular to dural fibres. Travel distance and peak force at which dural penetration occurred was measured under both pressure conditions. The work required to produce dural penetration was calculated. Greater force and work were required to penetrate dura in the perpendicular orientation (P < 0.05), regardless of the subdural pressure exterted. Dural displacement was similar under both pressure conditions. Comment by Hemmo A. Bosscher, MD.Work is the product of displacement and force (the area under the curve). The same amount of work is required whether the dura is under pressure (sitting position) or not (lying down). This is surprising. Absolute force is, therefore, not the most important factor. Penetration of the dura probably depends more on local pressure, the area of contact between needle and dura, and the structure of the dura (eg, fiber direction). A sharp needle will obviously penetrate much easier than a blunt one. Considering the shape of a Tuohy needle you would expect that the area of contact not only depends on orientation of the needle, but also strongly on the angle at which the dura is approached. Since dural puncture with a Tuohy needle in a young person almost invariably results in a “spinal headache” most benefit will be obtained from reducing the change of dural puncture. This study supports the concept of putting the bevel of the needle perpendicular to the fiber direction to reduce this change.
Clinical Science (40)
Authors: Ferguson Sue A. , Marras William S. , Gupta Purnendu 
Published: September 2010

Longitudinal quantitative measures of the natural course of low back pain. (Ohio State University, Columbus, OH) Spine 2000;25:1950–1956.This prospective study compared traditional self‐report measures of low back pain recovery with quantitative measure of recovery. Sixteen occupational and 16 non‐occupational patients with low back pain were recruited. Recovery was monitored prospectively every 2 weeks for 3 to 6 months, using subjective work status, pain symptoms, activities of daily living, and objective functional performance probability (trunk kinematics). Return to work underestimated the percentage of subjects impaired, as compared with all other outcome measures. Symptoms, activities of daily living, and functional performance probability all showed similar patterns of recovery for 0 to 12 weeks. At 14 weeks, there was a lag in functional performance recovery. Both symptoms and activities of daily living indicated that 80% of the population was recovered, whereas functional performance indicated the figure to be 68%. Conclude that the objective kinematic functional performance measure of recovery quantifies a different aspect of impairment not evaluated by traditional subjective measures. Use of several outcome measures may lead to a better understanding of low back pain recovery or residual impairment, which may minimize the risk of recurrent injury. Comment by Hemmo A. Bosscher, MD.This study evaluates several traditional and not so traditional quantitative measures in the recovery of low back pain. The authors hypothesize that a better understanding of the natural course of low back pain (LBP) recovery may provide the knowledge necessary to prevent high cost recurrent low back injuries. But the relationship between acute low back pain, its recovery, and the subsequent recurrence of LBP is not studied here at all. However the study offers some other interesting information. The traditional outcome measure “back to work” is a very insensitive one. It depends on the job rather than the severity of the LBP. A relatively new functional outcome measure was introduced: the lumbar motion monitor, a device that evaluates trunk kinematics. This measure seems more important in later stages of recovery.
Medicine (46)
Authors: Watson Peter N. 
Published: September 2010

The treatment of neuropathic pain: antidepressants and opioids. (University of Toronto, Ontario, Canada) Clin J Pain 2000;16:S49–S55.This article reviewed the scientific data on antidepressants and opioids, which are largely confined to randomized controlled trials in two neuropathic pain conditions that have proved to be good models for clinical investigation. A review of literature was conducted using MEDLINE, CINAHL, and the Cochrane Database regarding postherpetic neuralgia and painful diabetic neuropathy. The use of the older antidepressants such as amitriptyline in neuropathic pain was extensively supported by the literature. However, newer randomized controlled trials supported the use of opioids. Conclude that first‐line therapy for neuropathic pain may be either an older generation antidepressant such as amitriptyline or nortriptyline or the anticonvulsant gabapentin. For refractory cases, chronic opioid therapy may be the only avenue of relief, and evidence is accumulating that this approach is safe if proper guidelines are observed.
Neurology (48)
Authors: Kooijman Carolien M. , Dijkstra Pieter U. , Geertzen Jan H.B. , Elzinga Albert , Van der Schans Cees P. 
Published: September 2010

Phantom pain and phantom sensations in upper limb amputees: an epidemiological study. (University Hospital Groningen, Groningen, The Netherlands) Pain 2000;87:33–41.This study determined the prevalence and factors associated with phantom pain and phantom sensations in upper limb amputees in The Netherlands. Additionally, the relationship between phantom pain, phantom sensations, and prosthesis use in upper limb amputees was investigated. One hundred twenty‐four upper limb amputees participated in the study. Subjects were asked to fill out a self‐developed questionnaire scoring the following items: date, side, level, and reason of amputation, duration of experienced pain before amputation, frequencies with which phantom sensations, phantom pain, and stump pain are experienced, amount of trouble and suffering experienced, respectively, related to these sensations, type of phantom sensations, medical treatment received for phantom pain and/or stump pain, and the effects of the treatment, self medication, and prosthesis use. The response rate was 80%. The prevalence of phantom pain was 51%, of phantom sensations 76%, and of stump pain 49%; 48% of the subjects experienced phantom pain a few times per day or more. Moderate to severe suffering from phantom pain was experienced by 64% of the respondents. A significant association was found between phantom pain and phantom sensations (relative risk 11.3) and between phantom pain and stump pain (relative risk 1.9). No other factors associated with phantom pain or phantom sensations could be determined. Only 4 patients received medical treatment for their phantom pain. Phantom pain is a common problem in upper limb amputees that causes considerable suffering for the subjects involved. Only a small number of subjects are treated for phantom pain. Conclude that further research is needed to determine factors associated with phantom pain.
Neurology (49)
Authors: Khattab Jihad , Terebelo Howard R. , Dabas Basel 
Published: September 2010

Phantom limb pain as a manifestation of paclitaxel neurotoxicity. (Providence Hospital, Southfield, MI) Mayo Clin Proc 2000;75:740–742.This case report described 2 patients with prior amputation who experienced phantom limb pain (PLP) after receiving paclitaxel therapy. A third patient experienced disabling neurotoxicity in the extremity of a prior ulnar nerve and tendon transposition after receiving paclitaxel. This unique syndrome should be identified as a direct causal effect of paclitaxel. The pathophysiology of PLP and the treatment options are reviewed. Conclude that physicians should be aware that PLP can occur after initiation of paclitaxel.
Neurology (50)
Authors: Yaszay Burt , Jablecki Charles K. , Safran Marc R. 
Published: September 2010

Zoster paresis of the shoulder. (Stanford University School of Medicine, Stanford, CA) Clinical Orthopaedics and Related Research 2000;377:112–118.A case of unilateral left C5‐C6 segmental paresis attributable to herpes zoster in an otherwise healthy individual and a current review of literature are presented. A case of zoster paresis of the shoulder muscles is presented to remind the orthopedic community that this diagnosis may be confused with other diagnoses, including rotator cuff tear, and should be considered in the differential diagnosis of shoulder pain and shoulder girdle muscle weakness.