Measuring quality of life in stroke subjects receiving an implanted neural prosthesis for drop foot

The aim was to determine if the treatment of a drop foot by means of an implantable two-channel peroneal nerve stimulator improves health-related quality of life (HRQoL). All subjects were measured at baseline and after a follow-up period of 12 and 26 weeks. Twenty-nine stroke survivors with chronic hemiplegia with drop foot who fulfilled the predefined inclusion and exclusion criteria were included in the present randomized controlled trial. The intervention group received an implantable two-channel peroneal nerve stimulator for correction of their drop foot. The control group continued using their conventional walking device, consisting of an ankle-foot orthosis, orthopedic shoes, or no device. HRQoL was assessed in two different ways: (i) by taking descriptive measures, that is, the Short Form-36 (SF-36; generic measure) and the Disability Impact Profile (DIP; specific measure); and (ii) by obtaining preference-based utilities both measured with the time trade-off (direct way) and by calculating them from the EuroQol (EQ-5D) and SF-36. A significant positive effect of the implantable device was found on the physical functioning domain, the general health domain, and the physical component summary score of the SF-36. For the DIP, a significant improvement was found on the domains mobility, self-care, and psychological status in the intervention group. Regarding the preference-based utility measures, a significant effect was found for the utility index calculated from the EQ-5D. The implantable two-channel peroneal nerve stimulator seems to be efficient to improve HRQoL, mainly the domains related to physical functioning. A relation was present between the utility indexes calculated from the EQ-5D and SF-36.