Poster Abstracts Friday, November 11, 2005 $501

1576 Individual but not group changes in sensation on the skin proximal to amputation / congenital absence of a limb indicate heterogeneity in Cortical Plasticity

Moore, C l, Ajan, y2. 1St Mary"s Hospital, UK; 2Manchester .Royal Infirmary, UK

Background: The demonstration of cortical plasticity/reorganisation as a result of acquired or congenital 'deafferentation" of a sensory cortex has not led to a unifying theory for phantom limb pain. We have performed a large study to look for correlation between sensory changes and pain. Methods: 24 patients with traumatic upper limb amputations, 24 subjects with a congenital absence of a limb and 24 normal controls were studied with ethics committee approval. Sensory acuity was measured using a method of point touch localization (locoguosia). With eyes closed the skin was touched briefly with a 70 mN nylon m o a t filament, with eyes open the subject then indicated verbally to the nearest millimetre on a ruler the position that they perceived the stimulus. The stump and the contra lateral upper ann were studied in a counterbalanced pattern with equal probability of side stimulated to negate focusing. Normal controls were studied on both upper arnts. In total, 30 trials were perforated on each limb with the mean of 10 matclffng trials (not in the first 10 to avoid learning effects) taken as the measure of locognosia. Results: Group data showed no significant difference in sensory acuity between the upper limbs in any of the three groups (p > 0.05). Some amputees however, show significantly improved acuity on the stump. Those with a congenital absence showed greater effects (p < 0.04). Conclusion: These results may reflect the use of the ~deafferented' sensory cortex in sensory processing in some patients although this plasticity would not account for pain phenomena.

1577 Complex Regional Pain Syndrome is associated with distoxted body hnage of tile atti~cted part

Moseley, G ~, Acerra, N z. 1Oxford University," :Royal Brisbane & Women's Hospital & The University of Queensland,

Background: Patients with complex regional pain syndrome type 1 (CRPS1), report that their affected limb feels odd, or excessively swollen. Similar reports are made post-stroke and in association with phantom limb pain, conditions that are similar to CRPS1 in symptomology, cortical changes and response to treatment. It seems possible that distorted body image is related to these similarities rather than simply a consequence of pain. We investigated tiffs possibility. Method: Fifty patients with CRPS1 of one hand and 18 patients with non-CRPS1 hand pain participated. Both limbs were photographed. The image was manipulated so that the affected limb was compressed or stretched to 85%, 90%, 95%, 100%, 105%, 110% or 115% of its true size, relative to the unaffected limb. With hands out of view, patients selected the image pair they thought was accurate. Results: Sixty-three percent of CRPS 1 patients selected image pairs in wlffch the affected limb was stretched (median selection -- 105%; mean (107%); which was more than non-CRPSI patients (median & mean -- 100%). In CRPSI patients, the selected image pair did not relate to pain intensity or actual size (P > 0.3), but did relate to duration of symptoms (r - 0.55,/(1,36) -- 15.5, P < 0.001). Conclusion: Distorted body image is common in CRPS1. It is not simply a consequence of pain. Similar distortions occur with sensory loss, e.g. local anaesthesia, stroke and phantom limb pain. Thus, the current finding may reflect disruption of sensory input from the affected area or cortical reorganisation, or both.

1578 Fibromyalgia in Venezuelan patients, more than a Rheumatologic disease

1Mosquera, I, 1Rojas, R, 1Lizarralde, M, 1Hernfindez, A, ~;~ Puccio, F. ~Instituto De Neurologia Y Neurociencias Aplieadas; :Instituto de Biornedicina UCV

Background: Fibromyalgia (FM) can be classified as a complex of clinical symptoms. However, the etiology and pathogenesis of FM still remain uncertain. The present study was undertaken to compare general pain, sleep disorders, depression and anxiety in primary FM and in FM patients with rheumatology diseases and neurology disorders. Methods: One hundred and sixty two FM patients who assisted to the Neurological and Neurosciences Institute, Caracas, Venezuela, were evaluating with a multidisciplinary team work. We perforated Hamilton depression and anxiety standardized psychometric scales. Sleep quality were evaluate using a patient interview and sensitivity analyses using a scored visual analogue scale. The FM patients were classified into three groups: primary FM patients (72%), FM with neurology disorders (115"/o) and FM patients with rheumatology diseases (112"/o). Results: All FM patients fulfilling ACR criteria. Forty five percent of the FM patients with neurology disorder and 43% of primary FM patients showed severe depression symptoms; in contrast with 25% of the FM patients with rheumatology disorders. The evaluation of sleep quality showed that 89 % (group 1), 90 % (group 2) and 75"/0 (group 3) of FM patients had sleep disorders, including less than 8 hours of sleep. Conclusion: These results indicated that patients with FM associated with neurology disorder shows similar results than primary FM patients in contrast to FM with rheumatology diseases suggesting that for the diagnosis of FM it will be important to include many other rheumatologic studies like neurological and psyclffatric evaluation in order to improve interdisciplinary combined treatments.

1579 Selective Lumbosacral Radiculography and block for treahnent of Lumbosaeral Radiculopathy

Shahien R l, Weksler V ~, Lerman A ~, Prober A a. 1NeurMogy Unit and Radiology, Rebecca Sieff Hospital, Soled, lsrael

Epidural injections for treatment of low back pain have been perforated for more than half a century. The pro cedure was o riginally performed as a blind technique with a potential for erroneous needle placement and injection of substances into undesired locations. Based on the high rate of erroneous needle placement associated with blind techniques, there has been considerable movement toward fluoroscopically guided injections into the epidural space using myelograplffc contrast prior (Selective nerve root block - SNRB). The risk of incorrectly placed intrathecal injections and consequences can be eliminated with this technique. This safe, efficacious and relatively painless procedure is ideally suited for outpatients. We will review the technique, imaging appearance and potential pitfalls associated with SNRB. During the years 2001-2002, selective lumbosacral radiculography and block were carried out in 34 patients on 73 nerve roots. On the average, 2-3 procedures were performed on each patient. In all cases, radiographic confirmation on nerve root compression (CT, MRI, myelography) was available. Results: The radicular symptoms disappeared in 8 patients (124"/o). 16 patients (48%) showed marked improvement and moderate improvement was seen in 7 patients (20%). Only 3 patients (19%) had no discernible effect. According to our experience, this method is technically simple and very useful. A variety of minor complications and side effects which may occur will be discussed.

1580 The efficacy, safety, and tolerability of Pregabalin treatment for Neuropafllic Pain assodated with Diabetic Peripheral Neuropathy or Postherpetie Neuralgia: findings froul tile analysis of 10 randonfzed clinical trials