抄録
The loss of a limb leads to sensorimotor modifications. Patients often vividly experience that the missing limb is still present (phantom limb), and that it can be moved at will. Transcranial magnetic stimulation (TMS) to the primary motor cortex (M1) of such amputees induces the sensation of movement of the phantom limb.
In this study, TMS was applied for functional mapping of the motor cortex in patients with deafferentation pain. We studied 7 patients with intractable deafferentation pain (phantom limb: 3, brachial plexus avulsion: 4) and 2 patients with spinal cord injury without pain. Navigation-guided TMS stimulated their cortices around the primary motor area. The motor evoked potential (MEP) and the TMS-induced sensation reported by the patients were recorded. In all the patients, TMS induced some sensation of their amputated or paralyzed limbs.In the patients with phantom limb pain, the sensation was evoked by TMS to both the contralateral and ipsilateral cerebral hemispheres.
Conversely, in the patients without pain, TMS to the ipsilateral hemisphere did not evoke sensations of their paralyzed arm.In conclusion, TMS demonstrated marked cortical reorganization across the cerebral hemispheres in those patients with phantom limb pain.