The Role of Peripheral Afferents in Modulating Post-stroke Central Pain
Trial Parameters
Brief Summary
Central post-stroke pain (CPP) is extremely difficult to relieve and responds very poorly to analgesics targeting neuropathic pain, probably because the mechanisms underlying this pain remain poorly understood. Stroke pain is traditionally considered to be of central origin and related to changes in the spinal cord and/or brain nociceptive systems. However, a recent study in a small cohort of patients has suggested that the peripheral nervous system (PNS) may have a role in the initiation and persistence of APD. The main objective of this prospective randomised controlled bicentric study (Raymond Poincaré and Ambroise Paré) in double blind and parallel groups against placebo (3 arms) will be to evaluate the efficacy of two peripheral nerve blocks performed 14 days apart on spontaneous neuropathic pain after stroke. The active treatments used for the blocks will be either lidocaine 20 mg/ml or levobupivacaine 1.25 mg/ml or placebo (saline)
Eligibility Criteria
Inclusion Criteria: 1. Patients aged 18 years and over with no maximum age (blocks are generally very well tolerated in the very elderly) 2. Pain in the upper or lower limb distal enough to be completely covered by a peripheral nerve block 3. Chronic pain for at least 6 months 4. Ischaemic or haemorrhagic stroke for at least 6 months documented clinically and by appropriate imaging (MRI) 5. Post-stroke central neuropathic pain defined as pain occurring in the aftermath of stroke meeting the criteria for probable or defined neuropathic pain according to the NeuPSIG algorithm and with a DN4 screening questionnaire score of at least 4 out of 10. 6. Spontaneous pain intensity greater than or equal to 4 out of 10 on an 11-point numerical scale (EN) at inclusion and randomisation (i.e. just before each block) 7. Patients affiliated to a social security scheme or beneficiaries of such a scheme 8. Stable oral analgesic pharmacological treatment for at least 2 weeks prior to inclusion 9. Accept