Objective Complex regional pain syndrome-1 (CRPS) is characterised by allodynia, autonomia and, sometimes, dystonia. Its course varies from mild and self-limiting to chronic fixed dystonia. We describe treatment of CRPS-1 related dystonia by deep brain stimulation (DBS).
Methods Patient-1 was diagnosed with CRPS-1 aged 13. A minor blow triggered severe leg pain, allodynia and autonomia. Dystonia progressed to involve trunk and all limbs, rendering her completely dependent for all care. She subsequently developed status dystonicus requiring treatment on paediatric intensive care unit. Patient-2 developed CRPS-1 following a minor injury at age 14, resulting in right arm allodynia and dystonia. Progression produced four-limb dystonia, rendering her wheel-chair bound. DBS electrodes were implanted into dorsolateral GPi by MRI-guided stereotaxis and connected to a pulse generator. Stimulation settings were adjusted by response. Burke Fahn Marsden Dystonia Rating Scale assessed dystonia severity and disability; Visual Analog Scale (VAS), Neuropathic Pain Scale (NPS) and Brief Pain Inventory (BPI), pain; SF-36, quality of life; Beck Anxiety and Depression Inventories (BAI; BDI), emotional state.
Results Patient-1 recovered from status dystonicus rapidly post-surgery. She could sit upright, functionally using hands and arms. Pain and allodynia reduced. Discharge was within 2 weeks. Several relapses were of reducing frequency and severity. 28 months post-surgery, dystonia severity has improved by 55%; disability by 59%; overall SF-36 by 115%. VAS has reduced by 20%; NPS by 13%; BPI by 34%; BAI by 56%; BDI by 66%.She is doing ‘A’ levels and applying to university. Patient-2's dystonia improved rapidly post-surgery; she was able to walk with a stick. Discharge was within 3 weeks. At 12 months, dystonia and allodynia acutely recurred. The DBS battery was depleted; there was significant improvement post-replacement. 27 months post-surgery, dystonia severity has reduced by 55%; disability by 60%; VAS by 67%; NPS by 52%; BPI by 49%; BAI by 73%, BDI by 56%. Overall SF-36 has improved by 57%.
Conclusions We have demonstrated for the first time DBS to produce significant reduction in dystonia and pain in CRPS-1.