There's a technique in physical therapy called 'constraint-induced movement therapy' that's been available to stroke victims for some years. Unfortunately it's rather personnel-intensive (i.e. not cheap), and it hasn't caught on as much as I believe it should. With luck, that will change.

An article in the journal Lancet Neurology describes the use of this type of therapy for people with weakness in one hand. Half the 200-odd patients with a stroke affecting the upper limb were assigned to wear a mitt on their unaffected hand throughout their waking hours, for 2 weeks. This forced them to use their affected hand while doing day-to-day activities, such as eating or grooming. After one year there were measurable improvements in the use of the affected hand - measured by weight lifting, grip strength, and the log of movement activity. The benefit recorded after one year was found to persist for an additional year.

Use of a mitt for 2 weeks is not very personnel-intensive (as compared with other constraint-induced movement therapy techniques). The greatest disadvantage now seems to be the extreme frustration experienced by the patient during this time. Only those with a strong will to succeed are likely to make the most of this approach, unless they have a stern, full-time physical therapist, or an equally determined caregiver. But the results show the effort is clearly worthwhile.