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)
Patients aged 18 years and over with no maximum age (blocks are generally very well tolerated in the very elderly)
Pain in the upper or lower limb distal enough to be completely covered by a peripheral nerve block
Chronic pain for at least 6 months
Ischaemic or haemorrhagic stroke for at least 6 months documented clinically and by appropriate imaging (MRI)
Inability or unwillingness to sign an informed consent
Person subject to a legal protection measure (safeguard of justice, curatorship, guardianship)
Patients with ongoing psychiatric pathology (major depression, psychosis) or cognitive disorders that prevent a good understanding of the protocol and questionnaires
Pain that is too widespread in one hemicycle or limb and cannot be adequately covered by blocks