F260 HEMIPLEGIC SHOULDER PAIN: SOME INDICATION FOR NEUROPATHIC MECHANISM

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POSTER SESSIONS / European Journal of Pain Supplements 5 (2011) 15–295

F260 HEMIPLEGIC SHOULDER PAIN: SOME INDICATION FOR NEUROPATHIC MECHANISM R. Defrin1 *, M. Rivel1 , G. Zeilig2 . 1 Physical Therapy, Faculty of Medicine, Tel-Aviv University, Tel-Aviv, 2 Neurological Rehabilitation, Sheba Medical Center, Tel-Hashomer, Israel Background and Aims: The mechanism of Hemiplegic Shoulder Pain (HSP) is un clear. Studies suggest that HSP has a musculoskeletal origin based on relatively high rates of shoulder subluxation and additional musculoskeletal problems in the affected shoulder. However similar finding were also seen in painfree hemiplegic shoulders. Our aim was thus to conduct somatosensory tests in order to explore whether the HSP has a neuropthic component as well. Methods: Hemiplegics with (n = 16) and without (n = 15) HSP as well as healthy controls (n = 14) participated. Warm-, cold-, heat-pain and touch thresholds were measured and graphestesia, allodynia and hyperpathia were evaluated in the hemiplegic and contralateral shoulder and in the hemiplegic lower extremity. CT/MRI scans of the brain were examined. Results: Heat-pain threshold in the hemiplegic shoulder and lower extremity of the HSP group was significantly higher than in controls (p < 0.01 and p < 0.001, respectively). In addition, the former exhibited higher rates of hyperpathia. Participants with HSP exhibited higher rates of damage in the parietal lobe (p < 0.05) and also exhibited higher rates of chronic pain in various other body regions in the affected side (p < 0.001). Conclusions: The sensory profile of participants with HSP and the location of their brain damage points to alterations in the spino-thalamo-cortical system and may suggest that HSP includes a neuropathic pain component, possibly of a central origin. Disclosure: None declared

F261 CHARACTERIZING NEUROPATHIC SYMPTOMS AFTER THORACOTOMY: A PROSPECTIVE STUDY W. Gandhi1,2 *, P. Ware1 , J.F. Asenjo3,4 , P. Schweinhardt1,2,5 . 1 The Alan Edwards Centre for Research on Pain, 2 Facutly of Dentistry, 3 The Alan Edwards Pain Management Clinic, McGill University, 4 Department of Anesthesiology, Montreal General Hospital, McGill University Hospital Centre, 5 Department of Neurology and Neurosurgery, Faculty of Medicine, McGill University, Montreal, QC, Canada Background: Based on questionnaire data, 30 to 50% of patients undergoing standard postolateral thoracotomy develop persistent pain after surgery. This pain is suggested to be neuropathic in nature (Maguire et al, 2006); and one recent study using qualitative sensory tests has indeed provided evidence for symptoms of neuropathy (Guastella et al, 2010). To examine the development of neuropathic symptoms following thoracotomy in more detail, we use quantitative sensory testing (QST) in this study. QST enables assessing the degree of neuropathic symptoms over time. Methods: Patients scheduled for postolateral thoracotomy undergo one baseline session before surgery and six monthly sessions after surgery. In each session, QST is performed according to the DFNS protocol (Rolke et al, 2006). All QST subtests are performed within the innervation area of the anterior cutaneous branch of the intercostal nerve at incision level but outside the primary skin lesion. Results are compared between operated side and the homologous contralateral side for each patient and testing session. Results: Five patients have been investigated to date. QST showed that after surgery, all patients had higher warm detection thresholds and four patients showed higher mechanical detection thresholds. Three patients were also less sensitive to vibration. In contrast, all patients demonstrated decreased pressure pain thresholds, indicating higher sensitivity to deep pressure. Conclusions: At this point, deep pressure pain appears to be a useful marker of positive neuropathic symptoms following

intercostal nerve damage whereas warm, mechanical and possibly vibration detection thresholds might be helpful indicators of negative neuropathic symptoms after thoracotomy. Disclosure: None declared

F262 THE APPLICATION OF ULTRASOUND-GUIDED PERIPHERAL NERVE BLOCKS IN CONDITIONS OF CHRONIC PERIPHERAL NEUROPATHIC PAIN: HOW TO OBTAIN LONG-LASTING ANALGESIA? G.H. Hans1,2 *, L. Sermeus2 , J. Liesmons1 , M. Vercauteren1,2 . 1 Multidisciplinary Pain Center (PCT), Antwerp University Hospital (UZA), 2 Department of Anesthesiology, University Hospital of Antwerp (UZA), Edegem, Belgium Background and Aims: Lately ultrasound-guided peripheral nerve blocks are increasingly used in the treatment of chronic peripheral neuropathic pain conditions. Such procedures not only provide highly selective diagnostic information, but also have an immediate therapeutic value. However, they often result in rather short-lasting analgesia, requiring repetitive application of these blocks. Methods: Our study group has performed an extensive literature search to identify possible therapeutic agents and/or procedures, to obtain long-lasting analgesia after ultrasound-guided peripheral nerve blocks. This literature search is extended with examples of individual patients (in whom different methods have been applied). Results: Several agents have been identified as possibly useful in the prolongation of analgesia after ultrasound-guided peripheral nerve block. One of these agents is botulin toxin. Another family of agents (to be applied directly to the nerve during an nerve block procedure) is the anti-TNF agents. A procedure that could be applied in order to significantly increase the analgesic duration is the application of pulsed radiofrequency to the sensitized nerve structure. However, almost nothing is known regarding the application features of (pulsed) radiofrequency to peripheral nerve structures. Conclusions: Different pharmacological agents could be applied to sensitized peripheral nerve structures in order to obtain longlasting analgesia. Radiofrequency could also be applied on these nerves. However, little or nothing is known regarding the dosages or application features that have to be applied. Larger scale randomized, controlled, studies are necessary. Disclosure: None declared

F263 CHRONIC POST-THORACOTOMY PAIN SYNDROME: A RETROSPECTIVE STUDY C. Yesildag1 , E. Erhan1 *, M.N. Deniz1 , U. Cagirici2 , A. Cakan2 , K. Turhan2 , I. Yegul1 . 1 Department of Anesthesiology, 2 Department of Thoracic Surgery, Ege University Medical Faculty, Izmir, Turkey Background and Aims: Chronic pain is common after thoracotomy. The goal of this study was to investigate the incidence of chronic post-thoracotomy pain and its impact on quality of life. Methods: 233 patients who had undergone a classic postero-lateral thoracotomy at our institution in the period between January 2007 and October 2009 were evaluated. Patients who had more than one operation, who were lost during follow-up were excluded. All of the patients were contacted by telephone and were questioned about the presence of post-thoracotomy pain. Patients who had post-thoracotomy pain were invited for face to face interview with a Pain Questionnaire Form. Results: 74 patients were excluded from the study. 112 out of 159 patients were contacted by telephone. The incidence of chronic post-thoracotomy pain was 56%. Pain Questionnaire revealed that 69.4% of patients had mild, 26.5% of patients had moderate, 4.1% of patients had severe chronic pain. Thirty-nine percent of the patients with pain took analgesia, 24% felt their pain was their worst medical problem and 24% reported it limited their daily